Conspiracy theorists and mystics drop in colloidal silver and crystals.
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KN: By the way, do you want my colloidal silver?
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Same goes for using essential oils, colloidal silver and steroids.
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" Rather than explain why each specific claim regarding colloidal silver was wrong, Sonya Angelone of the Academy of Nutrition and Dietetics simply told Motherboard that "it is not recommended to take colloidal silver by mouth.
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None of this has stopped people from ingesting colloidal silver, though.
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Between takes, Adlon took colloidal silver for her own sinus infection.
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Javier generally refuses to take antibiotics, so he tried colloidal silver instead.
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This fragrance-free hand cream taps colloidal oatmeal to soothe red, angry, inflamed skin.
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The products cited in the letters were teas, essential oils, tinctures and colloidal silver.
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They're considered "colloidal suspensions," materials with properties of more than one state of matter. Dude.
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Scientists have concluded, however, that colloidal silver does not have health benefits and could be dangerous.
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It is colloidal, this light, the sun wiggling as if across a braided river from above.
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Oz told Paltrow he uses colloidal silver as a daily throat spray, and so do his kids.
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Those items included teas, essential oils, tinctures and colloidal silver, which is also reportedly known as nanosilver.
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Every product is made with pure colloidal gold that claims to have healing and anti-aging properties.
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It's a rare but irreversible condition, and in most cases the culprit is overenthusiastic use of colloidal silver.
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Colloidal silver can cause argyria, in which a patient's skin permanently turns the color of a blue jay.
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It was during one of his late-night radio sessions that Javier first started hearing ads for colloidal silver.
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In 1999, the FDA released its "final rule" regarding over-the-counter drugs containing colloidal silver and silver salts.
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Bakker's show promotes sales of "Silver Solution," also known as colloidal silver, alongside vitamins, food rations, and heritage seeds.
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If blotchiness is a concern, Tatcha's The Indigo Cream ($85) combines reparative colloidal oatmeal with calming Japanese indigo extract.
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Colloidal silver is not safe or effective to treat any disease or symptoms, according to the Food and Drug Administration.
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Just imagine accounting for all the movements and interactions of the 750,000 particle analogs in this simulation of a colloidal gel!
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There's an entire field of research, known as colloidal science, that attempts to study atoms by making larger analogues for them.
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Colloidal oatmeal, the first ingredient in this bubble bath, is a common remedy for dry and itchy skin caused by eczema.
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It's like whipping up gold from scratch—only in modern times, the coveted substance might be a colloidal crystal or macromolecular assembly.
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The agencies issued warning letters to seven companies peddling products like "teas, essential oils, tinctures and colloidal silver" claiming to cure coronavirus.
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The products included teas, essential oils, tinctures and colloidal silver, the agency said in a joint statement with the Federal Trade Commission.
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Recent tests of modern colloidal silver products found they had no significant antimicrobial properties and left most bacteria unscathed (even after six minutes).
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Specifically, the letters cite the sales of teas, essential oils, tinctures, and colloidal silver that have been falsely marketed for use against coronavirus.
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Two other companies warned by the FTC, N-Ergetics and Vital Silver, were also selling colloidal silver, claiming it could treat the coronavirus.
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Like Alaffia, it has a simple ingredients list: colloidal oatmeal, pure saccharum officinarum (cane sugar), lathanol LAL powder (SLSA), allantoin, and corn starch.
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Less-severe sunburns can be soothed with home remedies, including aloe vera, cool compresses, colloidal oatmeal baths, topical hydrocortisone cream, and antihistamines, she adds.
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Stan Jones, a libertarian politician from Montana, started taking colloidal silver in advance of Y20133K, assuming the new millennium would cause a shortage in antibiotics.
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Clark's Botanicals Retinol Rescue Overnight Cream with Calming Colloidal Oatmeal is a potent blend of retinol and oatmeal that make it suitable for sensitive skin.
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Colloidal silver was one of her four wellness tips—she said she regularly sprays it under her tongue and on airplane seats to keep viruses away.
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Ultra-hydrating and barrier-repairing moisturizers with nurturing ingredients like ceramides or colloidal oatmeal, such as Skinceuticals Triple Lipid Restore 2:4:2 Anti-Aging Treatment.
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The cleanser, toner, and moisturizer formulations balance proven pore-clearers like salicylic acid and glycolic acid with skin soothers like colloidal sulfur, green tea, and aloe.
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With colloidal particles [like what you find in gels], even without interactions we've already been able to get as many as 50 of the known space groups.
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But last night's InfoWars broadcast—the conspiracy-peddling, colloidal silver-hawking, Trump-loving talk show hosted by angry ripe tomato Alex Jones—may have been peak Bitcoin.
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Earthbath All-Natural Oatmeal & Aloe Shampoo contains natural moisturizers like colloidal oatmeal and aloe to soothe dry, itchy skin with coconut-based cleansers to clean and deodorize.
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"We use a time-release version of retinol with colloidal oatmeal and red clover extract so that it is delicate enough to use every day," Clark tells us.
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Each and every product from the line is infused with rose flower water and colloidal gold — two ingredients that hydrate and serve as a shield to free radicals, respectively.
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In 1999 the FDA declared that over-the-counter products containing colloidal silver ingredients were "misbranded" and "not generally recognized as safe," banning its sale as an OTC drug.
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The serum contains hyaluronic acid, as Dr. Engelman recommends, but it also has colloidal oatmeal, peptides, collagen, and aloe, all of which work together to help calm irritated skin.
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On Wednesday, James sent cease-and-desist orders to two companies that sold colloidal silver, which has been cited as being not safe or effective to treat any disease.
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The products include teas, essential oils, tinctures and colloidal silver, which had been previously cited as not safe or effective for treating any disease, according to a press release.
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The formula utilizes active ingredients like salicylic acid, coal tar, and micronized sulfur, along with natural moisturizers like colloidal oatmeal and allantoin to hydrate the skin and promote healing.
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While this classic shaving cream might lack the colloidal oatmeal of one competitor or the shea butter and coconut oil of another, that doesn't mean it doesn't perform well.
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A Montessori teacher from Brooklyn, Rosemary Jacobs, became known as the "silver woman" for the argyria she developed from colloidal silver nasal drops a doctor prescribed her as a child.
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Drinking gold may not have caught on, and that guy may have turned blue from colloidal silver, but that just goes to show how comfortable we've become with precious metals.
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" They also claim in the video that the FDA's banning of colloidal silver is "the government trying to shut down anybody that's producing silver, because they know how effective it is.
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What the gel does have is colloidal oatmeal, a finely milled oat that is suspended in water and that readily absorbs into the skin, creating a protective barrier against the blade.
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From a consumer perspective, it's not easy to discern good evidence from bad, or a lack of research from a consensus perspective that something—like colloidal silver—has been evaluated and discarded.
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N-Ergetics, a company based in Oklahoma that sells colloidal silver, said in a statement that it was aware of the warning letter from the F.D.A., and it disputed the agency's assertions.
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The products include teas, essential oils, tinctures and colloidal silver, which have been cited as not safe or effective for treating any disease, the agency said in a statement with the Federal Trade Commission.
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So colloidal silver was mostly abandoned by the medical establishment, which moved on to safer and more effective applications of silver, such as in wound dressings or as an infection-fighting additive to joint replacements.
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Ingredients include aloe vera (soothes irritation); allantoin (cleans away dead skin); vitamin E (protects and nourishes); something called "colloidal oatmeal protectant" (soothes dry, itchy skin); menthyl lactate (cools and refreshes); and grapefruit essence (freshens naturally).
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On Monday, the Trump administration issued warning letters to seven companies that were selling fraudulent coronavirus products including teas, essential oils, tinctures and colloidal silvers, and ordered them to take corrective measures within 48 hours.
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In addition to the false story about the virus's origin, NewsGuard has also identified numerous "news" sites promoting false cures to the coronavirus, including some that are themselves potentially fatal, including bleach and colloidal silver.
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"One of my favorite brands is SkinFix, which makes products containing natural anti-inflammatory ingredients such as zinc and colloidal oatmeal, so you can feel safe about using them daily, even on your face," she says.
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Starting in the mid-nineties, he made a fortune from alternative hormone-replacement therapies and the sale of controversial supplements, such as colloidal silver, which he recommends for treating colds and the flu, and for promoting pet health.
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"If you make it with tap water, let's say, or if there's any salts in the water, you can end up with silver nitrates," which Group blames for health problems in people who have taken colloidal silver supplements.
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The FDA has had to crack down on wellness companies advertising so-called cures for the coronavirus earlier this month, including known scammy products like essential oils and colloidal silver, according to a statement from the regulatory body.
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Last month, ahead of Facebook's announcement, the Washington Post uncovered a bevy of private Facebook groups with membership ranging from thousands to hundreds of thousands of people, promoting debunked alternative cancer treatments like baking soda, colloidal silver, and frankincense.
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But Donald J. Trump, in fact, poses no dilemma for the guilt-ridden anti-war leftist; he's not a true isolationist like Ron Paul, the libertarian Republican who is now busy selling gold bars and colloidal silver to Trump's base.
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"Trevor Bauer says that the doctors' timeline for his return is based on outdated mainstream medicine and he's begun a course of blood transfusions and colloidal silver to rid his body of CIA nanites," Ringer staff writer Michael Baumann tweeted.
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There was a particularly high profile case of argyria in Paul Karason, known in the media as "Papa Smurf," who consumed a homemade colloidal silver solution after reading about it in an alternative health magazine and used a topical silver treatment on his face.
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On Monday, the Federal Trade Commission and the Food and Drug Administration sent warning letters to seven companies, including a show run by the televangelist and convicted fraudster Jim Bakker, accused of marketing products like teas, essential oils and colloidal silver as protection against coronavirus.
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Last week, Ms. James also sent a cease-and-desist letter to Mr. Bakker's show to stop allowing the sale of colloidal silver — in which small flakes of silver are suspended in fluid — after a guest claimed that it could "eliminate" the disease within 12 hours.
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Karason bought a device to make his own colloidal silver at home—a colloid is one substance dispersed through a second—and soon he was drinking a 10-ounce tumbler of the stuff daily, hoping to improve his general health, and dabbing it on his face for his dermatitis.
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"Study after study after study tells us that douches, cleanses, steams, vinegar, ph balancing products, aloe, colloidal silver, garlic or whatever else passing as the vaginal snake oil du jour at best do nothing but have real potential for harming good bacteria and/or disrupting the mucosal surface," she wrote.
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All that glitters is not gold, but at least some of it is this shimmery pink mist from Bliss — which, in addition to being laced with colloidal gold and rosewater, dispenses the perfect fine, not-makeup-disrupting spritz of essential hydrating ingredients like vitamin E, shea butter, and sunflower seed oil.
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The Blemish Cream was carefully formulated by Dr. Lee, and contains 3% colloidal sulfur, which Dr. Lee says, clears acne in a few different ways: by inhibiting the growth of acne-causing bacteria, regulating the skin's oil production, and exfoliating the skin as a keratolytic (which promotes healthy cell-turnover).
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The FDA sent warning letters to televangelist Jim Bakker and six companies at the beginning of the month for selling unapproved coronavirus drugs and treatment products, including teas, essential oils, tinctures and colloidal silver, which has been cited as not safe or effective for treating any disease, the agency said.
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Not only does it help calm the look of redness with hemp-derived cannabis sativa seed oil, 2% topical melatonin, and 5% colloidal oatmeal — yes, the same stuff your mama always made you bathe in at the first sight of a rash — but it also smoothes, revitalizes, and evens skin tone and texture.
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" In the Silver Bullet video, Dr. Group says that the FDA raided his offices because he was selling colloidal silver; the reason the FDA has banned it, he claims, is that it's a "threat to the pharmaceutical companies and a threat to doctor's visits, because it works so good in the body.
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Even as Facebook was starting to crack down on viral misinformation about vaccines, 'cures' like baking soda, colloidal silver, and frankincense were still gaining huge audiences there (our story helped to get Facebook to more aggressively limit the reach of false medical cures, although I still regularly see them in the natural medicine groups I joined for this story).
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Polycrystalline colloidal structures have been identified as the basic elements of submicrometre colloidal materials science. Ref.14 in Mangels, J.A. and Messing, G.L., Eds., Forming of Ceramics, Microstructural Control Through Colloidal Consolidation, I.A. Aksay, Advances in Ceramics, Vol. 9, p.
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Russel, W.B., et al., Eds. Colloidal Dispersions (Cambridge Univ. Press, 1989) [see cover] Colloidal crystals have found application in optics as photonic crystals.
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Examples of a stable and of an unstable colloidal dispersion. Colloidal particles are the components of a colloid. A colloid is a substance microscopically dispersed evenly throughout another substance. Such colloidal system can be solid, liquid, or gaseous; as well as continuous or dispersed.
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Monodisperse powders of colloidal silica, for example, may therefore be stabilized sufficiently to ensure a high degree of order in the colloidal crystal or polycrystalline colloidal solid which results from aggregation. The degree of order appears to be limited by the time and space allowed for longer-range correlations to be established. Such defective polycrystalline colloidal structures would appear to be the basic elements of sub-micrometer colloidal materials science, and, therefore, provide the first step in developing a more rigorous understanding of the mechanisms involved in microstructural evolution in high performance materials and components.
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Scheme of the colloidal probe technique for direct force measurements in the sphere-plane and sphere-sphere geometries. The colloidal probe technique is commonly used to measure interaction forces acting between colloidal particles and/or planar surfaces in air or in solution. This technique relies on the use of an atomic force microscope (AFM). However, instead of a cantilever with a sharp AFM tip, one uses the colloidal probe.
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The colloidal probe consists of a colloidal particle of few micrometers in diameter that is attached to an AFM cantilever. The colloidal probe technique can be used in the sphere-plane or sphere-sphere geometries (see figure). One typically achieves a force resolution between 1 and 100 pN and a distance resolution between 0.5 and 2 nm. The colloidal probe technique has been developed in 1991 independently by Ducker.
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Double layer interactions are relevant in a wide number of phenomena. These forces are responsible for swelling of clays. They may also be responsible for the stabilization of colloidal suspension and will prevent particle aggregation of highly charged colloidal particles in aqueous suspensions. At low salt concentrations, the repulsive double layer forces can become rather long-ranged, and may lead to structuring of colloidal suspensions and eventually to formation of colloidal crystals.
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Typically, colloids do not completely settle or take a long time to settle completely into two separated layers. The dispersed-phase particles have a diameter between approximately 1 and 1000 nanometers. Such particles are normally easily visible in an optical microscope, although at the smaller size range (), an ultramicroscope or an electron microscope may be required. Homogeneous mixtures with a dispersed phase in this size range may be called colloidal aerosols, colloidal emulsions, colloidal foams, colloidal dispersions, or hydrosols.
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Hydrogen ions from the surface of colloidal silica tend to dissociate in aqueous solution, yielding a high negative charge. Substitution of some of the Si atoms by Al is known to increase the negative colloidal charge, especially when it is evaluated at pH below the neutral point. Because of the very small size, the surface area of colloidal silica is very high. The colloidal suspension is stabilized by pH adjustment and then concentrated, usually by evaporation.
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The colloidal probe technique uses a standard AFM for the force measurements. But instead the AFM cantilever with an attached sharp tip one uses the colloidal probe. This colloidal probe is normally obtained by attaching a colloidal particle to a cantilever. By recording the deflection of the cantilever as a function of the vertical displacement of the AFM scanner one can extract the force acting between the probe and the surface as a function of the surface separation.
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Colloidal silicas are suspensions of fine amorphous, nonporous, and typically spherical silica particles in a liquid phase. Schematic representation of the silica gel surface. The surface of colloidal silica in contact with water is covered by siloxane bonds (≡Si–O–Si≡) and silanol groups (≡Si–OH). This makes colloidal silica very hydrophilic and capable of forming numerous hydrogen bonds.
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Smoke from a fire is an example of a colloidal system in which tiny particles of solid float in air. Just like true solutions, colloidal particles are small and cannot be seen by the naked eye. They easily pass through filter paper. But colloidal particles are big enough to be blocked by parchment paper or animal membrane.
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The colloidal probes are normally fabricated by gluing a colloidal particle to a tip-less cantilever with a micromanipulator in air. The subsequent rewetting of the probe may lead to the formation of nanosized bubbles on the probe surface. This problem can be avoided by attaching the colloidal particles under wet conditions in AFM fluid cell to appropriately functionalized cantilevers. While the colloidal probe technique is mostly utilized in the sphere-plane geometry, it can be also used in the sphere- sphere geometry.
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These finds were attractive for the self-assembled of colloidal crystal films for applications such as photonics. Recent advances have increased the application of coffee-ring assembly from colloidal particles to organized patterns of inorganic crystals.
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The scattering of light by colloidal particles is known as Tyndall effect.
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The dispersed-phase particles have a diameter of between approximately 5 and 200 nanometers. Soluble particles smaller than this will form a solution as opposed to a colloid. Colloidal systems (also called colloidal solutions or colloidal suspensions) are the subject of interface and colloid science. Suspended solids may be held in a liquid, while solid or liquid particles suspended in a gas together form an aerosol.
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Less commonly, addition of manganese, indium, and other elements can produce more unusual colors of gold for various applications. Colloidal gold, used by electron-microscopists, is red if the particles are small; larger particles of colloidal gold are blue.
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This type of procedure can be very advantageous in case of colloidal precipitates.
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A biocolloid is a colloid or colloidal mixture of plant or animal origin.
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Colloidal particles may also remain dispersed in liquids for long periods of time (days to years). This phenomenon is referred to as colloidal stability and such a suspension is said to be functionally stable. Stable suspensions are often obtained at low salt concentrations or by addition of chemicals referred to as stabilizers or stabilizing agents. The stability of particles, colloidal or otherwise, is most commonly evaluated in terms of zeta potential.
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Semiconductor quantum dots are often called colloidal quantum dots because these dots are made from binary compounds. One of the main optical properties of colloidal quantum dots is the ability to produce fluorescence. Chemists use the fluorescence for bio labeling and chemical analysis. Since, Cadmium and other metals have been proven to be toxic in biological environments more and more of the colloidal quantum dots being produced have been cadmium free.
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An yttrium-90 (90Y) colloidal suspension is used for radiosynovectomy in the knee joint.
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Colloidal fuel is denser than water, which allows it to be stored under water.
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Examples of glidants include magnesium stearate, fumed silica (colloidal silicon dioxide), starch and talc.
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Such defective polycrystalline colloidal structures would appear to be the basic elements of submicrometer colloidal materials science, and, therefore, provide the first step in developing a more rigorous understanding of the mechanisms involved in microstructural evolution in inorganic systems such as polycrystalline ceramics.
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Typical chemicals used as retention aids are: polyacrylamide (PAM), polyethyleneimine (PEI), colloidal silica, and bentonite.
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Aggregates begin as the colloidal fraction, which typically contains particles sized between 1 nm and several micrometers. The colloidal fraction of the ocean contains a large amount of organic matter unavailable to grazers. This fraction has a much higher total mass than either phytoplankton or bacteria but is not readily available due to size characteristics of the particles in relation to potential consumers. The colloidal fraction must aggregate in order to be more bioavailable.
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In 1923, Debye and Hückel reported the first successful theory for the distribution of charges in ionic solutions. . The framework of linearized Debye–Hückel theory subsequently was applied to colloidal dispersions by Levine and Dube . . who found that charged colloidal particles should experience a strong medium-range repulsion and a weaker long-range attraction. This theory did not explain the observed instability of colloidal dispersions against irreversible aggregation in solutions of high ionic strength.
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234, p. 84, (1976) Bulk properties of a colloidal crystal depend on composition, particle size, packing arrangement, and degree of regularity. Applications include photonics, materials processing, and the study of self- assembly and phase transitions. A collection of small 2D colloidal crystals with grain boundaries between them.
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E. Potthoff, D. Ossola, T. Zambelli & J. A. Vorholt. Bacterial adhesion force quantification by fluidic force microscopy. (2015) Nanoscale, 7 (9), 4070 – 4079. Colloidal experiments give the opportunity to measure interaction forces between colloidal particles and surfaces as well as the local elasticity of complex substrates.
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DDM was introduced in 2008 and it was applied for characterizing the dynamics of colloidal particles in Brownian motion. More recently it has been successfully applied also to the study of aggregation processes of colloidal nanoparticles, of bacterial motions and of the dynamics of anisotropic colloids.
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Equilibrium phase transitions (e.g. order/disorder), an equation of state, and the kinetics of colloidal crystallization have all been actively studied, leading to the development of several methods to control the self-assembly of the colloidal particles. Examples include colloidal epitaxy and space-based reduced-gravity techniques, as well as the use of temperature gradients to define a density gradient. This is somewhat counterintuitive as temperature does not play a role in determining the hard-sphere phase diagram.
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In physics, colloids are an interesting model system for atoms. Micrometre-scale colloidal particles are large enough to be observed by optical techniques such as confocal microscopy. Many of the forces that govern the structure and behavior of matter, such as excluded volume interactions or electrostatic forces, govern the structure and behavior of colloidal suspensions. For example, the same techniques used to model ideal gases can be applied to model the behavior of a hard sphere colloidal suspension.
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The containment of a uniformly dispersed assembly of strongly interacting particles in suspension requires total control over particle- particle interactions. Monodisperse colloids provide this potential. Monodisperse powders of colloidal silica, for example, may therefore be stabilized sufficiently to ensure a high degree of order in the colloidal crystal or polycrystalline colloidal solid which results from aggregation. The degree of order appears to be limited by the time and space allowed for longer-range correlations to be established.
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Additional forces beyond the DLVO construct have been reported to also play a major role in determining colloid stability. DLVO theory is not effective in describing ordering processes such as the evolution of colloidal crystals in dilute dispersions with low salt concentrations. It also can not explain the relation between the formation of colloidal crystals and salt concentrations. N. Ise and I. S. Sogami, Structure Formation in Solution: Ionic Polymers and Colloidal Particles, (Springer, New York, 2005).
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Using a single colloidal crystal, phonon dispersion of the normal modes of vibration modes were investigated using photon correlation spectroscopy, or dynamic light scattering. This technique relies on the relaxation or decay of concentration (or density) fluctuations. These are often associated with longitudinal modes in the acoustic range. A distinctive increase in the sound wave velocity (and thus the elastic modulus) by a factor of 2.5 has been observed at the structural transition from colloidal liquid to colloidal solid, or point of ordering.
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Eric Weeks' Information Page at Emory University He is most well known for his work on various aspects of the jamming (physics) phenomenon, specifically in colloidal glasses and colloidal supercooled liquids, although his research interests extend broadly into other types of complex fluids, as well as microrheology and granular materials.
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He prepared the first pure sample of colloidal gold, which he called 'activated gold', in 1857. He used phosphorus to reduce a solution of gold chloride. The colloidal gold Faraday made 150 years ago is still optically active. For a long time, the composition of the 'ruby' gold was unclear.
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Prieve, Dennis C. "Measurement of colloidal forces with TIRM." Advances in Colloid and Interface Science 82.1 (1999): 93-125.
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This corresponds to about 2 to 10 nanometers, and at 10 nm in diameter, nearly 3 million quantum dots could be lined up end to end and fit within the width of a human thumb. Idealized image of colloidal nanoparticle of lead sulfide (selenide) with complete passivation by oleic acid, oleyl amine and hydroxyl ligands (size ≈5nm) Large batches of quantum dots may be synthesized via colloidal synthesis. Due to this scalability and the convenience of benchtop conditions, colloidal synthetic methods are promising for commercial applications.
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Such measurements permit to make conclusions about the elastic or plastic deformation or eventual rupture in such systems. The colloidal probe technique provides a versatile tool to measure such forces between a colloidal particle and a planar substrate or between two colloidal particles (see figure above). The particles used in such experiments have typically a diameter between 1–10 μm. Typical applications involve measurements of electrical double layer forces and the corresponding surface potentials or surface charge, van der Waals forces, or forces induced by adsorbed polymers.
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When a small amount of hydrophilic colloid is added to hydrophobic colloids it may coagulate the latter. This is due to neutralisation of the charge on the hydrophobic colloidal particles. However, the addition of large amount of hydrophilic colloid increases the stability of the hydrophobic colloidal system. This is due to adsorption.
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Colloidal quantum dots irradiated with a UV light. Different sized quantum dots emit different colour light due to quantum confinement.
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Analogues of Laves phases can be formed by the self-assembly of a colloidal dispersion of two sizes of sphere.
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"Hindered diffusion of colloidal particles very near to a wall: Revisited." The Journal of Chemical Physics 113.3 (2000): 1228-1236.
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Humic substances account for 50 – 90% of cation exchange capacity. Similar to clay, char and colloidal humus hold cation nutrients.
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When aggregation occurs in a suspension composed of similar monodisperse colloidal particles, the process is called homoaggregation (or homocoagulation). When aggregation occurs in a suspension composed of dissimilar colloidal particles, one refers to heteroaggregation (or heterocoagulation). The simplest heteroaggregation process occurs when two types of monodisperse colloidal particles are mixed. In the early stages, three types of doublets may form : A + A → A2 : B + B → B2 : A + B → AB While the first two processes correspond to homoaggregation in pure suspensions containing particles A or B, the last reaction represents the actual heteroaggregation process.
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In 1842, John Herschel invented a photographic process called chrysotype (from the Greek χρῡσός meaning "gold") that used colloidal gold to record images on paper. Modern scientific evaluation of colloidal gold did not begin until Michael Faraday's work in the 1850s. In 1856, in a basement laboratory of Royal Institution, Faraday accidentally created a ruby red solution while mounting pieces of gold leaf onto microscope slides. Since he was already interested in the properties of light and matter, Faraday further investigated the optical properties of the colloidal gold.
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This process is called Ostwald ripening. An important advantage of digestion is observed for colloidal precipitates where large amounts of adsorbed ions cover the huge area of the precipitate. Digestion forces the small colloidal particles to agglomerate which decreases their surface area and thus adsorption. You should know that adsorption is a major problem in gravimetry in case of colloidal precipitate since a precipitate tends to adsorb its own ions present in excess, Therefore, forming what is called a primary ion layer which attracts ions from solution forming a secondary or counter ion layer.
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Individual particles repel each other keeping the colloidal properties of the precipitate. Particle coagulation can be forced by either digestion or addition of a high concentration of a diverse ions strong electrolytic solution in order to shield the charges on colloidal particles and force agglomeration. Usually, coagulated particles return to the colloidal state if washed with water, a process called peptization. 4\. Washing and Filtering the Precipitate: It is crucial to wash the precipitate thoroughly to remove all adsorbed species that would add to the weight of the precipitate.
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Diffusiophoresis, by definition, moves colloidal particles, and so the applications of diffusiophoresis are to situations where we want to move colloidal particles. Colloidal particles are typically between 10 nanometres and a few micrometres in size. Simple diffusion of colloids is fast on lengthscales of a few micrometres, and so diffusiophoresis would not be useful, whereas on lengthscales larger than millimetres, diffusiophoresis may be slow as its speed decreases with decreasing size of the solute concentration gradient. Thus, typically diffusiophoresis is employed on lengthscales approximately in the range a micrometre to a millimetre.
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Depletion forces in colloid-polymer mixtures drive colloids to form aggregates that are densely packed locally. This local dense packing is also observed in colloidal systems without polymer depletants. Without polymer depletants the mechanism is similar, because the particles in dense colloidal suspension act, effectively, as depletants for one another This effect is particularly striking for anisotropically shaped colloidal particles, where the anisotropy of the shape leads to the emergence of directional entropic forces that are responsible for the ordering of hard anisotropic colloids into a wide range of crystal structures.
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In a colloidal suspension, particles will settle very slowly or not at all because the colloidal particles carry surface electrical charges that mutually repel each other. This surface charge is most commonly evaluated in terms of zeta potential, the electrical potential at the slipping plane. To induce coagulation, a coagulant (typically a metallic salt) with the opposite charge is added to the water to overcome the repulsive charge and "destabilize" the suspension. For example, the colloidal particles are negatively charged and alum is added as a coagulant to create positively charged ions.
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Blinking colloidal nanocrystals is a phenomenon observed during studies of single colloidal nanocrystals that show that they randomly turn their photoluminescence on and off even under continuous light illumination. This has also been described as luminescence intermittency. Similar behavior has been observed in crystals made of other materials. For example, porous silicon also exhibits this affect.
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These forces are easily experienced when hands are washed with soap. Adsorbing soap molecules make the skin negatively charged, and the slippery feeling is caused by the strongly repulsive double layer forces. These forces are further relevant in many colloidal or biological systems, and may be responsible for their stability, formation of colloidal crystals, or their rheological properties.
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Suspensions of gold nanoparticles of various sizes. The size difference causes the difference in colors. Colloidal gold is a sol or colloidal suspension of nanoparticles of gold in a fluid, usually water. The colloid is usually either an intense red colour (for spherical particles less than 100 nm) or blue/purple (for larger spherical particles or nanorods).
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Exponential divergence of correlation times of a Kosterlitz–Thouless transition. Left inset shows the domain structure of a 2D colloidal mono-layer for large cooling rates at the fall-out time. The right inset shows the structure for small cooling rates (after additional coarsening) a late times. Domain size as function of cooling rate in a colloidal mono-layer.
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Brines brought to the surface by geothermal energy production often contain concentrations of dissolved silica of about 500 parts per million. A number of geothermal plants have pilot-tested recovery of colloidal silica, including those at Wairakei, New Zealand, Mammoth Lakes, California, and the Salton Sea, California. To date, colloidal silica from brine has not achieved commercial production.
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Colloidal particles in a sol are continuously bombarded by the molecules of the dispersion medium on all sides. The impacts are however not equal in every direction. As a result, the sol particles show random or zig-zag movements. This random or zig-zag motion of the colloidal particles in a sol is called Brownian motion or Brownian movement.
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Thus diffusiophoresis always occurs in a mixture, typically a three- component mixture of water, salt and a colloidal species, and we are interested in the cross-interaction between the salt and the colloidal particle. It is the very large difference in size between the colloidal particle, which may be 1μm across, and the size of the ions or molecules, which are less than 1 nm across, that makes diffusiophoresis closely related to diffusioosomosis at a flat surface. In both cases the forces that drive the motion are largely localised to the interfacial region, which is a few molecules across and so typically of order a nanometer across. Over distances of order a nanometer, there is little difference between the surface of a colloidal particle 1 μm across, and a flat surface.
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The solubility of colloidal silica in alkaline solutions is higher than network silica, and thus can be removed by an alkaline after-treatment.
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In 1922, Hermann Staudinger refined the colloidal association theory of Thomas Graham by proposing that certain colloids were composed of high molecular weight polymers (chains linked by covalent bonds), which he termed 'macromolecules' to distinguish them from colloidal clusters of lower molecular weight molecules. So strongly held was colloidal association theory that even Emil Fischer, who had concluded that proteins are polypeptides formed by covalent bonds between amino acid units in 1906, initially refused to believe in the existence of high molecular weight polymers. Staudinger eventually received the Nobel Prize in 1953.Nobel Prize in Chemistry 1953.
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Colloidal particles may be hundred of nanometres or larger in diameter, while the interfacial double layer region at the surface of the colloidal particle will be of order the Debye length wide, and this is typically only nanometres. So here, the interfacial width is much smaller than the size of the particle, and then the gradient in the smaller species drives diffusiophoretic motion of the colloidal particles largely through motion in the interfacial double layer. Diffusiophoresis was first studied by Derjaguin and coworkers in 1947.Derjaguin, B.V., Sidorenko, G.P., Zubashenko, E.A. and Kiseleva, E.B. , Kolloid Zh., vol.
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Colloidal fuel is an emulsion of powdered coal in kerosene or fuel oil. It was used in World War I aboard ships as kerosene supplies ran low. Development continued after the war, and in 1932 the Cunard liner Scythia made a round- trip transatlantic voyage partly powered by colloidal fuel containing 40% coal. Advantages over oil included cost and energy density.
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Normally, the lens capsule serves as a diffusion barrier. It is permeable to low molecular weight compounds but restricts the movement of large colloidal particles.
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The tin chloride is oxidised to stannic acid and the gold chloride is reduced to metallic gold forming a colloidal precipitation onto the stannic acid.
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The effect of applying ultrasound has been considered with a view to comminuting precipitates produced under low shear to the colloidal scale to form coacervates.
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Charged surfaces are extremely important and are used in many applications. For example, solutions of large colloidal particles depend almost entirely on repulsion due to surface charge in order to stay dispersed. If these repulsive forces were to be disrupted, perhaps by the addition of a salt or a polymer, the colloidal particles would no longer be able to sustain suspension and would subsequently flocculate.
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Experiments in Fluids 50, 1183–1206 (2010).doi:10.1007/s00348-010-0996-8 Due to the moderate dielectric constant of CXB (ε = 7.9 ), PMMA acquires charges that can be screened by the addition of salt (e.g. tetrabutyl ammonium bromide), leading to a very good approximation of colloidal hard sphere.Royall, C. P., Poon, W. C. K. & Weeks, E. R. In search of colloidal hard spheres.
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A representation of core-shell nanocrystals Studies of single colloidal nanocrystals show that they randomly turn their photoluminescence on and off even under continuous light illumination. This tends to hinder progress for engineers and scientists who study single colloidal nanocrystals and try to use their fluorescent properties for biological imaging or lasing. The blinking in nanocrystals was first reported in 1996. The discovery was unexpected.
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Furthermore, the texture of porous glasses is influenced by the concentration of the extraction medium and the ratio of fluid to solid. Also, colloidal silica is solving in the sodium-rich borate phase, when time and temperature of thermal treatment are increased. This process is called secondary decomposition. The colloidal silica deposit in the macro pores during extraction and obscure the real pore structure.
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In Materials science and Colloidal chemistry, the term colloidal particle is about a small amount of matter having size typical for colloids and with a clear phase boundary. The dispersed-phase particles have a diameter between approximately 1 and 1000 nanometers. Colloids are heterogeneous in nature. Invisible to the naked eye, and always move in a zig-zag motion known as the Brownian motion.
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PolyDADMAC is used in waste water treatment as a primary organic coagulant which neutralizes negatively charged colloidal material and reduces sludge volume compared with inorganic coagulants.
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Urachal cancer usually is an adenocarcinoma (about 90%) mostly with mucinous/colloidal histology. Other rare types include urothelial carcinoma, squamous cell carcinoma, neuroendocrine carcinoma and sarcoma.
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HgSe is strictly mercury(II) selenide. HgSe occurs naturally as the mineral Tiemannite. Along with other II-VI compounds, colloidal nanocrystals of HgSe can be formed.
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Iodine (in the form of Lugol's solution) and colloidal silver are universally used in packaging that lets through very little UV light so as to avoid degradation.
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In these systems, lactylates are added to decrease the interfacial tension between the mutually insoluble components providing stability to the mixture, referred to as a colloidal suspension.
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Silica, either colloidal, precipitated, or pyrogenic fumed, is a common additive in food production. It is used primarily as a flow or anti-caking agent in powdered foods such as spices and non-dairy coffee creamer, or powders to be formed into pharmaceutical tablets. It can adsorb water in hygroscopic applications. Colloidal silica is used as a fining agent for wine, beer, and juice, with the E number reference E551.
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Colloidal silicas are most often prepared in a multi- step process where an alkali-silicate solution is partially neutralized, leading to the formation of silica nuclei. The subunits of colloidal silica particles are typically in the range of 1 to 5 nm. Whether or not these subunits are joined together depends on the conditions of polymerization. Initial acidification of a water-glass (sodium silicate) solution yields Si(OH)4.
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This type of AFM operation is referred to as the force mode. With this probe, one can study interactions between various surfaces and probe particles in the sphere-plane geometry. It is also possible to study forces between colloidal particles by attaching another particle to the substrate and perform the measurement in the sphere-sphere geometry, see figure above. Principle of the force measurements by the colloidal probe technique.
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In many different types of colloidal gold syntheses, the interface of the nanoparticles can display widely different character – ranging from an interface similar to a self-assembled monolayer to a disordered boundary with no repeating patterns. Beyond the Au-Ligand interface, conjugation of the interfacial ligands with various functional moieties (from small organic molecules to polymers to DNA to RNA) afford colloidal gold much of its vast functionality.
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Applications include moving particles into or out of pores of that size, and helping or inhibiting mixing of colloidal particles. In addition, solid surfaces that are slowly dissolving will create concentration gradients near them, and these gradients may drive movement of colloidal particles towards or away from the surface. This was studied by Prieve in the context of latex particles being pulled towards, and coating, a dissolving steel surface.
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Non-membrane bound organelles can form as biomolecular condensates, which arise by clustering, oligomerisation, or polymerisation of macromolecules to drive colloidal phase separation of the cytoplasm or nucleus.
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Quantum Dots with gradually stepping emission from violet to deep red There are several ways to fabricate quantum dots. Possible methods include colloidal synthesis, self-assembly, and electrical gating.
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Colloidal phase separation is an important organising principle for compartmentalisation of both the cytoplasm and nucleus of cells into biomolecular condensates, similar in importance to compartmentalisation via lipid bilayer membranes - a type of liquid crystal. The term biomolecular condensate has been used to refer to clusters of macromolecules that arise via liquid-liquid or liquid-solid phase separation within cells. Macromolecular crowding strongly enhances colloidal phase separation and formation of biomolecular condensates.
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Ligand exchange can also be used to promote phase transfer of the colloidal particles. Ligand exchange is also possible with alkane thiol-arrested NPs produced from the Brust-type synthesis method, although higher temperatures are needed to promote the rate of the ligand detachment. An alternative method for further functionalization is achieved through the conjugation of the ligands with other molecules, though this method can cause the colloidal stability of the Au NPs to breakdown.
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The C-S-H is strongly hydrophilic, and has a colloidal microstructure disordered from a few nanometers up. The paste has a porosity of about 0.4 to 0.55 and an enormous internal surface area, roughly 500 m2/cm3. Its main component is the tri-calcium silicate hydrate gel (3 CaO · 2 SiO3 · 3 H20, in short C3-S2-H3). The gel forms particles of colloidal dimensions, weakly bound by van der Waals forces.
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Octadecene is used in the synthesis of colloidal quantum dots, but it can possibly be replaced by heat transfer fluids such as Dowtherm A or Therminol 66 in this process.
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The cysts are found in the liver and spleen. Once mature the schizonts become extracellular, convoluted and filled with abundant colloidal substance. They are of medium size (diameter 250 micrometres).
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Chekesha M. Liddell Watson (née Liddell) is an Associate Professor of Material Science and Engineering at Cornell University. She researches colloidal materials, trying to understand their properties, structure and function.
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The journal covers research on thin-film synthesis, characterization, and applications, including synthesis, surfaces, interfaces, colloidal behavior, metallurgical topics, mechanics (including nanomechanics), electronics, optics, optoelectronics, magnetics, magneto-optics, and superconductivity.
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Pear-syrup candies with colloidal medicine, grain-like electuaries, cough reduction, various herbs, and Sichuan fritillary bulbs all contribute to treating cough, tracheitis, asthma, and other illnesses to some extent.
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Jennifer A. Lewis (born 1964) is an American materials scientist and engineer, best known for her research on colloidal assembly of ceramics and 3D printing of functional, structural, and biological materials.
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The precise structure of the ligands on the surface of colloidal gold NPs impact the properties of the colloidal gold particles. Binding conformations and surface packing of the capping ligands at the surface of the colloidal gold NPs tend to differ greatly from bulk surface model adsorption, largely due to the high curvature observed at the nanoparticle surfaces. Thiolate-gold interfaces at the nanoscale have been well-studied and the thiolate ligands are observed to pull Au atoms off of the surface of the particles to for “staple” motifs that have significant Thiyl-Au(0) character. The citrate-gold surface, on the other hand, is relatively less-studied due to the vast number of binding conformations of the citrate to the curved gold surfaces.
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Colloid-facilitated transport designates a transport process by which colloidal particles serve as transport vector of diverse contaminants in the surface water (sea water, lakes, rivers, fresh water bodies) and in underground water circulating in fissured rocks (limestone, sandstone, granite, ...). The transport of colloidal particles in surface soils and in the ground can also occur, depending on the soil structure, soil compaction, and the particles size, but the importance of colloidal transport was only given sufficient attention during the 1980 years. Radionuclides, heavy metals, and organic pollutants, easily sorb onto colloids suspended in water and that can easily act as contaminant carrier. Various types of colloids are recognised: inorganic colloids (clay particles, silicates, iron oxy- hydroxides, ...), organic colloids (humic and fulvic substances).
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Six factors can contribute to the formation of edema: # increased hydrostatic pressure; # reduced colloidal or oncotic pressure within blood vessels; # increased tissue colloidal or oncotic pressure; # increased blood vessel wall permeability (e.g., inflammation); # obstruction of fluid clearance in the lymphatic system; # changes in the water retaining properties of the tissues themselves. Raised hydrostatic pressure often reflects retention of water and sodium by the kidneys. Generation of interstitial fluid is regulated by the forces of the Starling equation.
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All of the experiments have led to at least one common conclusion: colloidal crystals may indeed mimic their atomic counterparts on appropriate scales of length (spatial) and time (temporal). Defects have been reported to flash by in the blink of an eye in thin films of colloidal crystals under oil using a simple optical microscope. But quantitatively measuring the rate of its propagation provides an entirely different challenge, which has been measured at somewhere near the speed of sound.
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Estimated force between two charged colloidal particles with radius of 1 μm and surface charge density 2 mC/m2 suspended in a monovalent electrolyte solutions of different molar concentrations as indicated. The scheme sketches the charged colloidal particles screened by the electrolyte ions. Double layer forces occur between charged objects across liquids, typically water. This force acts over distances that are comparable to the Debye length, which is on the order of one to a few tenths of nanometers.
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Peptization or Deflocculation is the process responsible for the formation of converting precipitate into colloid by shaking with it an electrolyte. This is particularly important in colloid chemistry or for precipitation reactions in an aqueous solution. When colloidal particles bear a same sign electric charge, they mutually repel each other and cannot aggregate together. Freshly precipitated aluminium or iron hydroxide is extremely difficult to filter because the very fine colloidal particles directly pass through a paper filter.
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Overbeek's dissertation explored the role of the deformation of the electrical double layer surrounding a charged colloidal particle which was set in motion by an external electric field. After graduation Overbeek joined Philips, where Evert Verwey, was his immediate boss. In addition to work on luminescent screens they worked together on the interaction between colloidal particles. Attraction, based on the summation of the London - van der Waals interactions between the atoms was established in 1937 by HamakerH.
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In 1941, Derjaguin and Landau introduced a theory for the stability of colloidal dispersions that invoked a fundamental instability driven by strong but short- ranged van der Waals attractions countered by the stabilizing influence of electrostatic repulsions. . Seven years later, Verwey and Overbeek independently arrived at the same result. . This so-called DLVO theory resolved the failure of the Levine–Dube theory to account for the dependence of colloidal dispersions' stability on the ionic strength of the electrolyte. .
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Foam is a type of colloidal dispersion where gas is dispersed throughout a liquid phase. The liquid phase is also called the continuous phase because it is an uninterrupted, unlike the gas phase.
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The term quantum dot was coined in 1986. They were first discovered in a glass matrix and in colloidal solutions by Alexey Ekimov and Louis Brus. They were first theorized by Alexander Efros.
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Dukhin, S.S. and Derjaguin, B.V. (1974) Electrokinetic Phenomena, J. Willey and Sons.Russel, W.B., Saville, D.A., and Schowalter, W.R. (1989) Colloidal Dispersions, Cambridge University Press.Kruyt, H.R. (1952) Colloid Science, Elsevier. Volume 1, Irreversible systems.
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Colloidal gold is used in research applications in medicine, biology and materials science. The technique of immunogold labeling exploits the ability of the gold particles to adsorb protein molecules onto their surfaces. Colloidal gold particles coated with specific antibodies can be used as probes for the presence and position of antigens on the surfaces of cells. In ultrathin sections of tissues viewed by electron microscopy, the immunogold labels appear as extremely dense round spots at the position of the antigen.
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Hatton has published widely on colloidal phenomena and their applications in chemical processing. His research interests include responsive surfactants and gels obtained by colloidal self-assembly, stimuli-responsive materials, chemically reactive fibers and fabrics, metal-organic frameworks for separations and catalysis, and synthesis and functionalization of magnetic nanoparticles and clusters. Much of his work focuses on the development of purification technologies of various kinds. In the 1980s, he studied the effects of metal ions, clays, and minerals on sorption capacities.
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He was born in Penwortham, Lancashire. He was educated at the Royal Grammar School Worcester. He went to University College, Oxford, gaining a degree in Chemistry. He remained at Oxford, and researched colloidal materials.
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Random lasing has been reported from a large variety of materials, e.g. colloidal solutions of dye and scattering particles,N. Lawandy et al. "Laser action in strongly scattering media" Nature, 368, 436–438 (1994). .
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Kathleen Stebe is a scientist with areas of expertise in Nanostructured Materials, as well as Surface and Colloidal Science. She is also a Professor of Chemical and Biomolecular Engineering at The University of Pennsylvania.
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Consequently, numerous alternative theories of the protein primary structure were proposed, e.g., the colloidal hypothesis that proteins were assemblies of small molecules, the cyclol hypothesis of Dorothy Wrinch, the diketopiperazine hypothesis of Emil Abderhalden and the pyrrol/piperidine hypothesis of Troensgard (1942). Most of these theories had difficulties in accounting for the fact that the digestion of proteins yielded peptides and amino acids. Proteins were finally shown to be macromolecules of well-defined composition (and not colloidal mixtures) by Theodor Svedberg using analytical ultracentrifugation.
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This discovery led to the development of a new criterion for distinguishing gels from soft glass.Winter, H. H. (2013) Glass transition as the rheological inverse of gelation. Macromolecules 46, 2425-2432 With Alessio Zaccone, they also developed rheological scaling laws for colloidal gels, which take into account the power-law growth kinetics in the colloidal self-assembly. Winter also contributed to the numerical modeling of polymer processing operations and his 1977 paper on viscous dissipation in flowing polymer systems is widely considered a classic in the area.
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The structure factor of Figure 1 is calculated from the positions of a colloidal monolayer (crosses at high intensity are artefacts from the Fourier transformation due to the finite (rectangular) field of view of the ensemble).
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In addition, phase transitions in colloidal suspensions can be studied in real time using optical techniques, and are analogous to phase transitions in liquids. In many interesting cases optical fluidity is used to control colloid suspensions.
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Several alternative therapies are claimed by their proponents to be helpful for including milk thistle, ginseng, and colloidal silver.Hepatitis C and CAM: What the Science Says . National Center for Complementary and Alternative Medicine (NCCAM). March 2011.
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Fractals is a peer-reviewed scientific journal devoted to explaining complex phenomena using fractal geometry and scaling. It is published by World Scientific and has explored diverse topics from turbulence and colloidal aggregation to stock markets.
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Spherical glass particles (10 μm diameter) in water. The connectivity of the crystals in the colloidal crystals above. Connections in white indicate that particle has six equally spaced neighbours and therefore forms part of a crystalline domain.
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Anhydrous aluminium zirconium tetrachlorohydrex gly functions by diffusing into the sweat gland and forming a colloidal "plug" which limits the flow of sweat to the skin surface. The plug is gradually broken down and normal sweating resumes.
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The term lyotropic has also been applied to the liquid crystalline phases that are formed by certain polymeric materials, particularly those consisting of rigid rod-like macromolecules, when they are mixed with appropriate solvents. Examples are suspensions of rod-like viruses such as the Tobacco Mosaic Virus as well as man-made colloidal suspensions of non-spherical colloidal particles. Cellulose and cellulose derivatives form lyotropic liquid crystal phases as do nanocrystalline ( nanocellulose ) suspensions. Other examples include DNA and Kevlar, which dissolve in sulfuric acid to give a lyotropic phase.
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The science is not particularly well understood. It has been known for years that silica sols (also known as colloidal silica, silicic acid, polysilicic acid) will gel when exposed to temperatures around 0 °C (32 °F). The theoretical mechanism is quite simple: Colloidal silica is produced by the polymerisation of monosilicic acid, Si(OH)4, until the chains of polysilicic acid become so long they form silica particles with hydroxylated surfaces. On freezing of the sol, the silica particles are rejected away from the solidifying interface and forced into the interstices between the ice crystals.
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Electrophoretic Deposition Process Electrophoretic deposition (EPD), is a term for a broad range of industrial processes which includes electrocoating, cathodic electrodeposition, anodic electrodeposition, and electrophoretic coating, or electrophoretic painting. A characteristic feature of this process is that colloidal particles suspended in a liquid medium migrate under the influence of an electric field (electrophoresis) and are deposited onto an electrode. All colloidal particles that can be used to form stable suspensions and that can carry a charge can be used in electrophoretic deposition. This includes materials such as polymers, pigments, dyes, ceramics and metals.
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These casein proteins form a multi molecular colloidal particle known as a casein micelle. The proteins mentioned have an affinity to bind with other casein proteins, or to bind with calcium phosphate, and this binding is what forms the aggregates. The casein micelles are aggregates of β-caseins, α(s1)-caseins, α(s2)-caseins, that are coated with κ-caseins. The proteins are held together by small clusters of colloidal calcium phosphate, the micelle also contains lipase, citrate, minor ions, and plasmin enzymes, along with entrapped milk serum.
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Colloidal gold and various derivatives have long been among the most widely used labels for antigens in biological electron microscopy. Colloidal gold particles can be attached to many traditional biological probes such as antibodies, lectins, superantigens, glycans, nucleic acids, and receptors. Particles of different sizes are easily distinguishable in electron micrographs, allowing simultaneous multiple-labelling experiments. In addition to biological probes, gold nanoparticles can be transferred to various mineral substrates, such as mica, single crystal silicon, and atomically flat gold(III), to be observed under atomic force microscopy (AFM).
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Pusey is a pioneer of dynamic light scattering (DLS) and is known for elucidating the structure and dynamics of concentrated colloidal suspensions. He contributed to the development, underlying theory and applications of DLS. He was among the first to apply photon correlation techniques and, with colleagues, developed the now standard method of cumulant analysis for particle sizing. His theory, with William van Megen, of DLS by non-ergodic media resolved long-standing difficulties, allowing DLS studies of amorphous solid-like systems such as polymer gels and glassy colloidal suspensions.
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DLVO theory is a theory of colloidal dispersion stability in which zeta potential is used to explain that as two particles approach one another their ionic atmospheres begin to overlap and a repulsion force is developed. In this theory, two forces are considered to impact on colloidal stability: Van der Waals forces and electric double layer forces. The total potential energy is described as the sum of the attraction potential and the repulsion potential. When two particles approach each other, electrostatic repulsion increases and the interference between their electrical double layers increases.
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There are many different smectic phases, all characterized by different types and degrees of positional and orientational order. Beyond organic molecules, Smectic ordering has also been reported to occur within colloidal suspensions of 2-D materials or nanosheets.
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Their molecules are typically nonpolar or little polar, and they do not undergo ionization. They are insoluble in water. They form a colloidal solution in solvents. They have poor (basic dyes) to good (metal complex based) light fastness.
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"USM professor develops self-repairing plastic material". Mississippi Business Journal, 19 August 2012. and many others have featured his research group (Urban Research Group) discoveries in stimuli-responsive polymers, including self-healing films, colloidal synthesis, and antimicrobial surfaces.
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Drawing inks can be divided into two groups: India ink and polymer inks. India ink is used on paper and drafting film plastics. The most commonly used India ink is a colloidal mixture of water and carbon black.
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It also exhibits a strong tendency to bind to colloidal particulates, an effect that is enhanced when in soil with a high clay content. The behavior provides an additional aid in the element's observed high mobility.Atwood, section 1.
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The polymers that serve as plasticizers exhibit surfactant properties. They are often ionomers. They function as dispersants to minimize particle segregation (gravel, coarse and fine sands). The negatively charged polymer backbone adsorbs on the positively charged colloidal particles.
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General procedure for coating colloid particles in silica. First PVP is absorbed onto the colloidal surface. These particles are put into a solution of ammonia in ethanol. the particle then begins to grow by addition of Si(OEt)4.
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Secondary treatment is expected to remove 85 percent of soluble and colloidal organic pollutants from sewage containing 200 mg/L BOD;U.S. Environmental Protection Agency (EPA). Washington, DC. "Secondary Treatment Regulation." Code of Federal Regulations, 40 CFR Part 133.
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" Colloidal oatmeal may be beneficial in psoriasis. Aloe vera may help in atopic dermatitis. In both these conditions, the benefit may arise from anti- inflammatory properties. "For combating acne and rosacea, green tea, niacinamide and feverfew are considered efficacious.
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Colloidal platinum NPs protected by Poly(N-isopropylacrylamide) were synthesised and their catalytic properties measured. It was determined that they were more active in solution and inactive when phase separated due to its solubility being inversely proportional to temperature.
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"Complex Dynamics of Glass-Forming Liquids: A Mode- Coupling Theory." No direct experimental evidence supports the existence of these transitions. The gelation transition of colloidal particles has been shown to be a second-order phase transition under nonequilibrium conditions.
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Soluble and colloidal black carbon retained on the landscape from wildfires can make its way to groundwater. On a global scale, the flow of black carbon into fresh and salt water bodies approximates the rate of wildfire black carbon production.
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Other catalytic enzymes such as alkaline phosphatase can be used instead of peroxidases for both direct and indirect staining methods. Alternatively, the primary antibody can be detected using fluorescent label (immunofluorescence), or be attached to colloidal gold particles for electron microscopy.
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All 3 models consider micelles as colloidal particles formed by casein aggregates wrapped up in soluble κ-casein molecules. Milk-clotting proteases act on the soluble portion, κ-casein, thus originating an unstable micellar state that results in clot formation.
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Quantum dots synthesized by plasma are usually in the form of powder, for which surface modification may be carried out. This can lead to excellent dispersion of quantum dots in either organic solvents or water (i. e., colloidal quantum dots).
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Hedi Mattoussi is a Tunisian-American materials scientist and Professor at Florida State University. His research considers colloidal inorganic nanocrystals for biological imaging and sensing. He is a Fellow of the American Physical Society, American Chemical Society and Materials Research Society.
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The word "emulsion" comes from the Latin emulgere "to milk out," from ex "out" + mulgere "to milk", as milk is an emulsion of fat and water, along with other components, including colloidal casein micelles (a type of secreted biomolecular condensate).
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Dried nasal mucus (booger), with hanging viscous mucus Dried nasal mucus, colloquially known as a boogie, booger, bogey, or snot is found in the nose. It is a result of drying of the normally viscous colloidal mucus, commonly known as snot.
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Perovskite MAPbX3 thin films have been shown to be promising materials for optical gain applications such as lasers and optical amplifiers. Afterwards, the lasing properties of colloidal perovskite NCs such as CsPbX3 nanocubes, MAPbBr3 nanoplatelets and FAPbX3 nanocubes were also demonstrated. Thresholds as low as 2 uJ cm−2 have been reported for colloidal NCs (CsPbX3) and 220 nJ cm−2 for MAPbI3 nanowires. Interestingly, perovskite NCs show efficient optical gain properties not only under resonant excitation, but also under two-photon excitation where the excitation light falls into the transparent range of the active material.
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A colloidal crystal is a highly ordered array of particles which can be formed over a long range (to about a centimeter). Arrays such as this appear to be analogous to their atomic or molecular counterparts with proper scaling considerations. A good natural example of this phenomenon can be found in precious opal, where brilliant regions of pure spectral color result from close-packed domains of colloidal spheres of amorphous silicon dioxide, SiO2 (see above illustration). The spherical particles precipitate in highly siliceous pools and form highly ordered arrays after years of sedimentation and compression under hydrostatic and gravitational forces.
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Moringa seed cake, obtained as a byproduct of pressing seeds to obtain oil, is used to filter water using flocculation to produce potable water for animal or human consumption. Moringa seeds contain dimeric cationic proteins which absorb and neutralize colloidal charges in turbid water, causing the colloidal particles to clump together, making the suspended particles easier to remove as sludge by either settling or filtration. Moringa seed cake removes most impurities from water. This use is of particular interest for being nontoxic and sustainable compared to other materials in moringa-growing regions where drinking water is affected by pollutants.
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Consumable metal plates, such as iron or aluminum, are usually used as sacrificial electrodes to continuously produce ions in the water. The released ions neutralize the charges of the particles and thereby initiate coagulation. The released ions remove undesirable contaminants either by chemical reaction and precipitation, or by causing the colloidal materials to coalesce, which can then be removed by flotation. In addition, as water containing colloidal particulates, oils, or other contaminants move through the applied electric field, there may be ionization, electrolysis, hydrolysis, and free-radical formation which can alter the physical and chemical properties of water and contaminants.
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Nanovid microscopy, from “nanometer video-enhanced microscopy”, is a microscopic technique aimed at visualizing colloidal gold particles of 20–40 nm diameter (nanogold, immunogold) as dynamic markers at the light-microscopic level. The nanogold particles as such are smaller than the diffraction limit of light, but can be visualized by using video-enhanced differential interference contrast (VEDIC). The technique is based on the use of contrast enhancement by video techniques and digital image processing. Nanovid microscopy, by combining small colloidal gold probes with video-enhanced quantitative microscopy, allows studying the intracellular dynamics of specific proteins in living cells.
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Lebedev, who is a widower, lives in Moscow, as does his other daughter, Yana, who has founded an online fashion guide. He frequently participates in sailing competitions on his RC44 yacht with the Russian sailing team Synergy. He is a helmsman and co-owner of this team. In 2013, Lebedev earned a PhD by Belgorad State Technological University in colloidal chemistry (the topic of PhD dissertation: Colloidal and electrochemical aspects of anticorrosion protection of structural steel in nuclear power plants equipment.) In 2017, it was reported in The Guardian that Lebedev had acquired Cypriot citizenship through a "Golden visa" scheme.
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The book introduces information on the formation of colloidal gold and its medical uses. About half a century later, English botanist Nicholas Culpepper published book in 1656, Treatise of Aurum Potabile, solely discussing the medical uses of colloidal gold. In 1676, Johann Kunckel, a German chemist, published a book on the manufacture of stained glass. In his book Valuable Observations or Remarks About the Fixed and Volatile Salts-Auro and Argento Potabile, Spiritu Mundi and the Like, Kunckel assumed that the pink color of Aurum Potabile came from small particles of metallic gold, not visible to human eyes.
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They are both relative motion of a surface and a solution, driven by a concentration gradient in the solution. This motion is called diffusiophoresis when the solution is considered static with particles moving in it due to relative motion of the fluid at the surface of these particles. The term diffusioosmosis is used when the surface is viewed as static, and the solution flows. A well studied example of diffusiophoresis is the motion of colloidal particles in an aqueous solution of an electrolyte solution, where a gradient in the concentration of the electrolyte causes motion of the colloidal particles.
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Most soils contain organic colloidal particles called humus as well as the inorganic colloidal particles of clays. The very high specific surface area of colloids and their net electrical charges give soil its ability to hold and release ions. Negatively charged sites on colloids attract and release cations in what is referred to as cation exchange. Cation-exchange capacity (CEC) is the amount of exchangeable cations per unit weight of dry soil and is expressed in terms of milliequivalents of positively charged ions per 100 grams of soil (or centimoles of positive charge per kilogram of soil; cmolc/kg).
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The current research of Xia and his group centers on the development of new chemistry, physics, and technological applications of nanostructured materials – a class of materials which feature sizes less than 100 nm. His research includes the chemistry and physics of nanomaterial synthesis, the application of nanomaterials to biomedical research, and developing nanomaterials for energy- and environment-related applications. Xia co-invented soft lithography while he was a PhD student with George M. Whitesides at Harvard University. As an independent researcher, he and his group have made original and important contributions to the following areas: colloidal crystals and their photonic applications, colloidal assembly, one-dimensional nanostructures, electrospinning and alignment of nanofibers, electrospun nanofibers as scaffolds for tissue engineering, and shape-controlled synthesis of colloidal nanocrystals and their applications in plasmonics, spectroscopy, heterogeneous catalysis, and electrocatalysis, invention of silver nanostructures with many different morphologies such as nanowires and nanocubes, and invention of gold nanocages and exploration of their biomedical applications.
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He graduated at ELTE Apáczai Csere János Secondary School. In 1977 he began his studies at Eötvös Loránd University, where he gained his honours MSc degree in chemistry. One year later he got a dr. univ. rer. nat. title in colloidal chemistry.
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This is direct evidence of the thermal motion of atoms, which cause the Brownian motion of the colloidal particles in the milk, which in turn results in the dynamic speckle visible to the naked eye. Biospeckle laser image sequence of a maize seed.
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W. B. Russel, D. A. Saville, W. R. Schowalter, Colloidal Dispersions. Cambridge University Press: Cambridge, 1989. An electrical double layer develops near charged surfaces (or another charged objects) in aqueous solutions. Within this double layer, the first layer corresponds to the charged surface.
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The water is kept cold as an ice bath. The colloidal particle prepared is stabilised by adding a small amount of potassium hydroxide to it. This method is not suitable when the dispersion medium is an organic liquid as considerable charring occurs.
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In this method, hot chloroauric acid is treated with sodium citrate solution, producing colloidal gold. The Turkevich reaction proceeds via formation of transient gold nanowires. These gold nanowires are responsible for the dark appearance of the reaction solution before it turns ruby-red.
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Micro stickies are transported with the pulp to the paper machine and might agglomerate and cause problematic deposits there. Stickies often have thermoplastic properties. Chemical-physical alterations like pH, temperature and charge changes might cause colloidal destabilization and agglomeration of micro stickies.
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A method for testing the behavior of shear thickening fluids is stochastic rotation dynamics-molecular dynamics (SRD-MD). The colloidal particles of a shear thickening fluid are simulated, and shear is applied. These particles create hydroclusters which exert a drag force resisting flow.
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" Current opinion in colloid & interface science 2.6 (1997): 600-606. In this manner, sub-picoNewton forces may be detected.Flicker, Scott G., Jennifer L. Tipa, and Stacy G. Bike. "Quantifying double-layer repulsion between a colloidal sphere and a glass plate using total internal reflection microscopy.
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Cations that can reduce and deposit on the platinum can be source of interference: silver, mercury, copper, lead, cadmium and thallium. Substances that can inactivate ("poison") the catalytic sites include arsenic, sulfides and other sulfur compounds, colloidal substances, alkaloids, and material found in living systems.
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The manufacturing process is quite simple. A press forms the pot shape out of clay mixed with rice husks. The pot is fired, and the husk burns, leaving small holes that the water can run through. Finally the filters are coated with colloidal silver.
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The electrical double layer (EDL) is the result of the variation of electric potential near a surface, and has a significant influence on the behaviour of colloids and other surfaces in contact with solutions or solid-state fast ion conductors. The primary difference between a double layer on an electrode and one on an interface is the mechanisms of surface charge formation. With an electrode, it is possible to regulate the surface charge by applying an external electric potential. This application, however, is impossible in colloidal and porous double layers, because for colloidal particles, one does not have access to the interior of the particle to apply a potential difference.
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The applications of this oxide strengthening technique are important for solid oxide fuel cells and water filtration devices. To process a sample through ice templating, an aqueous colloidal suspension is prepared containing the dissolved ceramic powder evenly dispersed throughout the colloid, for example Yttria-stabilized zirconia (YSZ). The solution is then cooled from the bottom to the top on a platform that allows for unidirectional cooling. This forces ice crystals to grow in compliance to the unidirectional cooling, and these ice crystals force the dissolved YSZ particles to the solidification front of the solid-liquid interphase boundary, resulting in pure ice crystals lined up unidirectionally alongside concentrated pockets of colloidal particles.
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The three most-cited papers published by the journal are: # Research Article: Development of a novel autothermal reforming process and its economics for clean hydrogen production, Volume 1, Issue 1-2, Nov-Dec 2006, Pages: 5-12, Chen ZX, Elnashaie SSEH # Research Article: Review: examining the use of different feedstock for the production of biodiesel, Volume 2, Issue 5, Sep- Oct 2007, Pages: 480-486, Behzadi S, Farid MM # Research Article: The forces at work in colloidal self-assembly: a review on fundamental interactions between colloidal particles, Volume 3, Issue 3, May-Jun 2008, Pages: 255-268, Li Q, Jonas U, Zhao XS, et al.
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German-Swiss chemist Christian Friedrich Schönbein created the explosive substance nitrocellulose, or "guncotton", in 1846 by treating cotton fibers with a nitric acid and sulphuric acid mixture. However, guncotton proved to be too fast burning for direct use in firearms and artillery ammunition. French chemist Paul Vieille then followed the findings of Schönbein in 1882–84 and, after much trial and error, succeeded in transforming guncotton into a colloidal substance by gelatinizing it in an alcohol-ether mixture which he then stabilized with amyl alcohol. He then used roller presses to transform this gelatinized colloidal substance into extremely thin sheets which, after drying, were cut up into small flakes.
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Under the Tyndall effect, the longer wavelengths are more transmitted while the shorter wavelengths are more diffusely reflected via scattering. The Tyndall effect is seen when light-scattering particulate matter is dispersed in an otherwise light-transmitting medium, when the diameter of an individual particle is the range of roughly between 40 and 900 nm, i.e. somewhat below or near the wavelengths of visible light (400–750 nm). It is particularly applicable to colloidal mixtures and fine suspensions; for example, the Tyndall effect is used in nephelometers to determine the size and density of particles in aerosols and other colloidal matter (see ultramicroscope and turbidimeter).
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However, total silica analysis becomes more critical in UPW, where the presence of colloidal silica is expected due to silica polymerization in the ion exchange columns. Colloidal silica is considered more critical than dissolved in the electronic industry due to the bigger impact of nano-particles in water on the semiconductor manufacturing process. Sub-ppb (parts per billion) levels of silica make it equally complex for both reactive and total silica analysis, making the choice of total silica test often preferred. Although particles and TOC are usually measured using on-line methods, there is significant value in complementary or alternative off-line lab analysis.
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The DLVO theory of colloidal stability has been extended to take into account the effect of shear flow in fluid dynamic systems, which is relevant for many applications e.g. microfluidics, chemical reactors, atmospheric and environmental flows, in the work of Alessio Zaccone and collaborators. In this extended DLVO theory for sheared systems, the DLVO energy barrier for aggregation gets reduced by a negative contribution which is proportional to the Péclet number of the particles, i.e. proportional to the shear rate, to the viscosity of the medium, and to the cube of the colloidal particle size, while the proportionality coefficient depends on the flow geometry.
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The first LEDs based on colloidal CsPbX3 NCs demonstrated blue, green and orange EL with sub-1% EQE. Since then, efficiencies have reached above 8% for green LEDs (CsPbBr3 NCs), above 7% for red LEDs (CsPbI3 NCs), and above 1% for blue LEDs (CsPb(Br/Cl)3).
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Jim and Spence are at the December 1972 night launch of Apollo 17.p. 61, p. 76 Jim sees Spence talk with the Chilean McKenna,p. 86 who later talks to Jim about his "economical prisoner" (George Foley) who has a theory of the Colloidal Unconscious.
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The complexity of the simulations arise from the system having a large number of degrees of freedom, and from the numerous possible interparticle interactions having place, such as friction, hydrodynamic interactions, and other kinds of interparticle forces such as colloidal forces that exert attractive or repulsive forces.
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Engineered nanomaterials have been deliberately engineered and manufactured by humans to have certain required properties. Legacy nanomaterials are those that were in commercial production prior to the development of nanotechnology as incremental advancements over other colloidal or particulate materials. They include carbon black and titanium dioxide nanoparticles.
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Signalosomes are large supramolecular protein complexes that undergo clustering (oligomerisation or polymerisation) and/or colloidal phase separation to form biomolecular condensates that increase the local concentration and signalling activity of the individual components. They are an example of molecular self-assembly and self-organisation in cell biology.
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Potential difference as a function of distance from particle surface. Generally, gold nanoparticles are produced in a liquid ("liquid chemical methods") by reduction of chloroauric acid (). To prevent the particles from aggregating, stabilizing agents are added. Citrate acts both as the reducing agent and colloidal stabilizer.
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Depletion forces are used extensively as a method of destabilizing colloids. By introducing particles into a colloidal dispersion, attractive depletion forces can be induced between dispersed particles. These attractive interactions bring the dispersed particles together resulting in flocculation.Casey, T.J. "Unit Treatment Processes in Water and Wastewater Engineering".
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Surface charge emits an electric field, which causes particle repulsion and attraction, affecting many colloidal properties. Surface charge practically always appears on the particle surface when it is placed into a fluid. Most fluids contain ions, positive (cations) and negative (anions). These ions interact with the object surface.
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William H. Betz and L. Drew Betz founded their water purification business in Philadelphia, Pennsylvania in 1925. Betz's first product was K-Gel, a colloidal substance used to purify boiler water. An initial year of sales netted the company $30,000. Betz continued to sell K-Gel for 50 years.
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Menachem Elimelech is the Roberto C. Goizueta professor of environmental and chemical engineering at Yale University. In 1998, he founded Yale's environmental engineering program, for which he continues to serve as director. Elimelech specializes in problems involving physicochemical, colloidal, and microbial processes in engineered and natural environmental systems.
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Through a proprietary manufacturing process that claims to break down metals into microscopic particles dispersed in water, metals such as titanium, gold, and silver are allegedly turned into hydro-colloidal metals (known as Aqua Titanium, Aqua Gold, and Aqua Silver, respectively) which are then incorporated into Phiten products.
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Precipitated sulfur and colloidal sulfur are used, in form of lotions, creams, powders, soaps, and bath additives, for the treatment of acne vulgaris, acne rosacea, and seborrhoeic dermatitis. Other topical uses included the treatment of superficial mycoses (infections with fungi) and scabies, but this is largely obsolete now.
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Tray of jello shots An alternative recipe calls for the addition of an alcoholic beverage to the mix, contributing approximately one third to one half of the liquid added after the gelatin has dissolved in a boil. A serving of the resulting mixture is called a "Jell-O shot" at parties. The quantity and timing of the addition of the liquor are vital aspects; it is not possible to make Jell-O shots with liquor alone, as the colloidal proteins in dry gelatin consist of chains which require a hot liquid to denature them before they can then reform as a semisolid colloidal suspension. Pure alcohol cannot be heated sufficiently to break down these proteins, as it evaporates.
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The colloidal protein hypothesis stated that proteins were colloidal assemblies of smaller molecules. This hypothesis was disproved in the 1920s by ultracentrifugation measurements by Theodor Svedberg that showed that proteins had a well-defined, reproducible molecular weight and by electrophoretic measurements by Arne Tiselius that indicated that proteins were single molecules. A second hypothesis, the cyclol hypothesis advanced by Dorothy Wrinch, proposed that the linear polypeptide underwent a chemical cyclol rearrangement C=O + HN \rightarrow C(OH)-N that crosslinked its backbone amide groups, forming a two-dimensional fabric. Other primary structures of proteins were proposed by various researchers, such as the diketopiperazine model of Emil Abderhalden and the pyrrol/piperidine model of Troensegaard in 1942.
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Entropic forces are important and widespread in the physics of colloids, where they are responsible for the depletion force, and the ordering of hard particles, such as the crystallization of hard spheres, the isotropic-nematic transition in liquid crystal phases of hard rods, and the ordering of hard polyhedra. Because of this, entropic forces can be an important driver of self-assembly Entropic forces arise in colloidal systems due to the osmotic pressure that comes from particle crowding. This was first discovered in, and is most intuitive for, colloid-polymer mixtures described by the Asakura–Oosawa model. In this model, polymers are approximated as finite-sized spheres that can penetrate one another, but cannot penetrate the colloidal particles.
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Millstone's lab concentrates on the chemical synthesis of multifunctional nanoparticles and techniques to study their structural- property relationships. They work on nanoparticle colloidal arrays and their mechanochemistry. They use nuclear magnetic resonance, photoemission spectroscopy and electron microscopy. She won the 2015 Unilever Award for Outstanding Young Investigator in Colloid & Surfactant Science.
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Polyelectrolytes are charged polymers capable of stabilizing (or destabilizing) colloidal emulsions through electrostatic interactions. Their effectiveness can be dependent on molecular weight, pH, solvent polarity, ionic strength, and the hydrophilic-lipophilic balance (HLB). Stabilized emulsions are useful in many industrial processes, including deflocculation, drug delivery, petroleum waste treatment, and food technology.
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As well as with Karstedt's catalyst, Speier's catalyst enjoys widespread use for hydrosilylation, the main drawback is the deliquescent properties of the catalyst. It is generally agreed that chloroplatinic acid is a precursor to the actual catalyst. A possible role for colloidal platinum or zero-valent complexes has also been considered.
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Colloidal suspensions are the subject of interface and colloid science. This field of study was introduced in 1845 by Italian chemist Francesco SelmiFrancesco Selmi, Studi sulla dimulsione di cloruro d'argento, Nuovi Annali delle Scienze Naturali di Bologna, fasc. di agosto 1845. and further investigated since 1861 by Scottish scientist Thomas Graham.
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Colloidal latex is first mixed with formic acid to cause it to coagulate. The coagulum is processed in a "creping battery", a series of machines that crush, press and roll the coagula. The sheets are hung in a heated drying shed and then sorted by grade and packed for shipping.
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Exchangeable colloidal AFM probes for the quantification of irreversible and long-term interactions. Biophysical Journal, 105 (2), 463 – 472. The method to perform a single bacteria adhesion experiment is the same as for single cells. It provides information about how bacterial cells interact with their surface and with each other.2015\.
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Electrophoretic Light Scattering (ELS) is primarily used for characterizing the surface charges of colloidal particles like macromolecules or synthetic polymers (ex. polystyrene) in liquid media in an electric field. In addition to information about surface charges, ELS can also measure the particle size of proteins and determine the zeta potential distribution.
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A polymer that has a high structural content of neutral sugar branches interacts with hesperidin more tightly and strongly than that of a low content of neutral sugar branches. The interaction between pectin and hesperidin is one of the factors that enable the colloidal suspension in orange juice to be stable.
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Gerbode works on studying dynamics in experimental two-dimensional colloidal crystals and plant biomechanics, notably on cucumber tendrils. Her work has been featured in the Cornell Chronicle, the American Physical Society's Physics, and NPR. According to Scopus, Gerbode's publications have received over 431 citations and her h-index is 10.
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Silicate anions in solution react with molybdate anions yielding yellow silicomolybdate complexes. In a typical preparation, monomeric orthosilicate was found to react completely in 75 seconds; dimeric pyrosilicate in 10 minutes; and higher oligomers in considerably longer time. In particular, the reaction is not observed with suspensions of colloidal silica.
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The photoacoustic immunoassay measures low-frequency acoustic signals generated by metal nanoparticle tags. Illuminated by a modulated light at a plasmon resonance wavelength, the nanoparticles generate strong acoustic signal, which can be measured using a microphone. The photoacoustic immunoassay can be applied to lateral flow tests, which use colloidal nanoparticles.
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Jones developed argyria, which permanently turned his skin a blue-grey color, by consuming home-made colloidal silver, which he made due to fears the Year 2000 problem would make antibiotics unavailable, an event that did not occur. The peculiar coloration of his skin featured prominently in media coverage of his unsuccessful campaign.
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When lyophilic sols are added to lyophobic sols, depending on their sizes, either lyophobic sol is adsorbed in the surface of lyophilic sol or lyophilic sol is adsorbed on the surface of lyophobic sol. The layer of the protective colloid prevents direct collision between the hydrophobic colloidal particles and thus prevents coagulation.
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Consequently, they have prolonged antithrombotic and colloidal effects. In this family, dextran-40 (MW: 40,000 Da), has been the most popular member for anticoagulation therapy. Close to 70% of dextran-40 is excreted in urine within the first 24 hours after intravenous infusion, while the remaining 30% are retained for several more days.
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Sea snot forms when globs of marine snow coagulate into large globs that can span distances as large as 124 miles. The mucilage has many components, including a wide range of microorganisms including viruses and prokaryotes, and exopolymeric compounds with colloidal properties. Sea snot is also produced by phytoplankton when they are stressed.
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Colloidal quantum dots irradiated with a UV light. Different sized quantum dots emit different colors of light due to quantum confinement. Quantum dots (QDs) are semiconductor particles a few nanometres in size, having optical and electronic properties that differ from larger particles due to quantum mechanics. They are a central topic in nanotechnology.
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Liddell creates photonic crystals for solar cells using colloidal building blocks. She has worked on the Self-assembly of microparticles with hemispherical and dimer shapes. Liddell joined the faculty of Cornell University in 2003. She is a member of the National Organization for the Professional Advancement of Black Chemists and Chemical Engineers.
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Vintage cranberry glass bowl Johann Kunckel. Cranberry glass or Gold Ruby glass is a red glass made by adding gold salts or colloidal gold to molten glass. Tin, in the form of stannous chloride, is sometimes added in tiny amounts as a reducing agent. The glass is used primarily in expensive decorations.
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Particle size is a notion introduced for comparing dimensions of solid particles (flecks), liquid particles (droplets), or gaseous particles (bubbles). The notion of particle size applies to colloidal particles, particles in ecology, particles present in granular material (whether airborne or not), and particles that form a granular material (see also grain size).
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"Methods of preparing polysilynes" With some solvents (tetrahydrofuran, ether, toluene etc.) it forms a colloidal suspension that is clear and non-viscous, which may then be deposited as a film or coating on various substrates. Upon thermolysis, poly(methylsilyne) decomposes to silicon carbide. The optical properties of these materials has attracted attention.
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When the limit of stability of the supersaturation is reached, the precipitate forms, and a clear region forms ahead of the diffusion front because the precipitate that is below the solubility limit diffuses into the precipitate. This was argued to be a critically flawed theory when it was shown that seeding the gel with a colloidal dispersion of the precipitate (which would arguably prevent any significant region of supersaturation) did not prevent the formation of the rings. Another theory focuses on the adsorption of one or the other of the precipitating ions onto the colloidal particles of the precipitate which forms. If the particles are small, the absorption is large, diffusion is "hindered" and this somehow results in the formation of the rings.
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Reductive colloidal syntheses as such have yielded tetrahedral, cubic, irregular-prismatic, icosahedral, and cubo-octahedral nanoparticles, whose dispersity is also dependent on the concentration ratio of capping agent to precursor, and which may be applicable to catalysis. The precise mechanism of shape-controlled colloidal synthesis is not yet known; however, it is known that the relative growth rate of crystal facets within the growing nanostructure determines its final shape. Polyol syntheses of platinum nanoparticles, in which chloroplatinic acid is reduced to PtCl42− and Pt0 by ethylene glycol, have also been a means to shape-controlled fabrication. Addition of varying amounts of sodium nitrate to these reactions was shown to yield tetrahedra and octahedra at high concentration ratios of sodium nitrate to chloroplatinic acid.
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Platinum NPs are used as catalysts for proton exchange membrane fuel cell (PEMFC), for industrial synthesis of nitric acid, reduction of exhaust gases from vehicles and as catalytic nucleating agents for synthesis of magnetic NPs. NPs can act as catalysts in homogeneous colloidal solution or as gas-phase catalysts while supported on solid state material. The catalytic reactivity of the NP is dependent on the shape, size and morphology of the particle One type of platinum NPs that have been researched on are colloidal platinum NPs. Monometallic and bimetallic colloids have been used as catalysts in a wide range of organic chemistry, including, oxidation of carbon monoxide in aqueous solutions, hydrogenation of alkenes in organic or biphasic solutions and hydrosilylation of olefins in organic solutions.
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Keim laid the foundation for the success of Keimfarben in 1878 with KEIM Purkristalat, a two-component pure silicate paint. The second generation of Keim paints followed in 1962 with Keim Granital, the first silicate emulsion paint; in contrast to Purkristalat, this is a one-component paint which makes it easier to apply. In 2002, Keimfarben then launched Keim Soldalit, a sol-silicate or colloidal silicate paint (binding agent: colloidal silica and water glass), which makes it much easier to apply silicate paints so that they are suitable for universal use. Keimfarben produces paint systems for external and internal use, mineral renders and fillers, natural stone repair systems and thermal insulation composite systems, together with concrete repair and surface protection systems.
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Therefore, it is used for dry necrotic wound, necrotic wound, pressure ulcers, and burn wound. It is not suitable for wounds with heavy discharge and infected wounds. Hydrocolloid dressing: This type of dressing contains two layers: inner colloidal layer and outer waterproof layer. It contains gel forming agents such as carboxymethylcellulose, gelatin and pectin.
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This method can be used to manipulate, detect, handle, and concentrate cells and virus in biomedical field; or, for colloidal particle assembly. In addition the induced vortices around the conducting surfaces in a microfluidic system can be used as a micro-valve, micro-actuator, micro-motor and micro- regulator to control the direction and manipulation.
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Colloidal particles can also serve as transport vector of diverse contaminants in the surface water (sea water, lakes, rivers, fresh water bodies) and in underground water circulating in fissured rocks (e.g. limestone, sandstone, granite). Radionuclides and heavy metals easily sorb onto colloids suspended in water. Various types of colloids are recognised: inorganic colloids (e.g.
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Furthermore, imperfections in the UCNP film will not affect data storage. These advantages yielded an impressive achieved storage limit, making UCNP films a promising material in optical storage. UCNPs can be applied in niche applications for displays and printing. Anti-counterfeiting codes or prints can be fabricated using UCNPs in existing colloidal ink preparations.
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In Alfacar and Viznar, Andalucia (Spain), P. furfuracea is used for respiratory complaints. The thallus is washed and boiled for a long time to prepare a decoction which is drunk. Water extracts of this species have been shown to have a potent protective effect on genotoxicity caused by bismuth compounds such as colloidal bismuth subcitrate.
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Sodium bentonite expands when wet, absorbing as much as several times its dry mass in water. Because of its excellent colloidal properties, it is often used in drilling mud for oil and gas wells and boreholes for geotechnical and environmental investigations.Hosterman, J.W. and S.H. Patterson. 1992. Bentonite and Fuller's earth resources of the United States.
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His research interests include soft condensed matter and complex fluids including polymers, colloids, and liquid crystals. He has investigated the development of new fabrication techniques for photonic crystals including colloidal self- assembly and multi-beam interference lithography. He was also involved in developing plastic transistors on flexible substrates for various applications, including electronic paper.
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A monodisperse aerosol, producible in the laboratory, contains particles of uniform size. Most aerosols, however, as polydisperse colloidal systems, exhibit a range of particle sizes.Hinds, 1999, p. 8. Liquid droplets are almost always nearly spherical, but scientists use an equivalent diameter to characterize the properties of various shapes of solid particles, some very irregular.
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J[ohn] Turkevich, P. C. Stevenson, J. Hillier, "A Study of the Nucleation and Growth Processes in the Synthesis of Colloidal Gold", Discuss. Faraday. Soc., 1951, 11, pp. 55–75, explains how to suspend gold nanoparticles in liquid. It owes its awakening to medicine, which now employs gold nanoparticles to detect tumors and deliver drugs.
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Hydrotherapy is a type of treatment based on an assortment of treatments dealing with water. Some of these treatments were needle showers, fan douches, jet douches, salt glows, general messages, local messages, sitz baths, foot baths, ultraviolet radiations, electric light cabinet baths, bubble baths, hot fomentations, colloidal baths, and surgical dressings."Ypsilanti State Hospital." Opacity.
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Since the 1940s, the DLVO theory has been used to explain phenomena found in colloidal science, adsorption and many other fields. Due to the more recent popularity of nanoparticle research, DLVO theory has become even more popular because it can be used to explain behavior of both material nanoparticles such as fullerene particles and microorganisms.
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These microrods are created by densely packing silica colloidal particles inside cylindrical pores. By solidifying the assembled structures the microrods were imaged and examined using scanning electron microscopy (SEM). Columnar arrangements are also investigated as a possible candidate of optical metamaterials (i.e. materials with a negative refractive index) which find applications in super lenses or optical cloaking.
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The blue curve is from computer simulations and shows a reduced elasticity due to lattice vibrations at T > 0 . The red curve is the renormalization following the recursion relations, Young's modulus disappears discontinuously to zero at 16 \pi . Turquoise symbols are from measurements of elasticity in a colloidal monolayer, and confirm the melting point at Y_R = 16 \pi .
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Degree (Candidate of Sciences, today PhD.) after defending her doctoral thesis "New Stabilization Methods with a view to shortening the lying time of beer". In 1980, she was appointed doctor of technical sciences (DrSc.) after defending her dissertation thesis on the study of the rationalization and modernization of methods of increasing the colloidal stability of beer.
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An early, and very common, method for synthesizing silver nanoparticles is citrate reduction. This method was first recorded by M. C. Lea, who successfully produced a citrate- stabilized silver colloid in 1889. Citrate reduction involves the reduction of a silver source particle, usually AgNO3 or AgClO4, to colloidal silver using trisodium citrate, Na3C6H5O7.Wojtysiak, Sebastian, and Andrzej Kudelski.
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Natural gums are vegetable exudates that are released as the result of damage to the plant such as that resulting from the attack of an insect or a natural or artificial cut. These exudates contain heterogeneous polysaccharides formed of different sugars and usually containing uronic acids. They form viscous colloidal solutions. There are different species that produce gums.
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Also often found together with Biggs jasper is a dark gray, somewhat translucent chert. It formed from colloidal silica released from the volcanic debris. Because of their different physical properties, water movement separated the two colloids from which the chert and Biggs jasper resulted from each other, so that both were deposited in nearly pure form.
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Porous membranes are intended on separation of larger molecules such as solid colloidal particles, large biomolecules (proteins, DNA, RNA) and cells from the filtering media. Porous membranes find use in the microfiltration, ultrafiltration, and dialysis applications. There is some controversy in defining a “membrane pore”. The most commonly used theory assumes a cylindrical pore for simplicity.
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Granick was a pioneer in the field of nanorheology and molecular tribology. Other early work concerned molecular mobility at polymer surfaces. This progressed to later studies showing how biological membranes interact with their environments. More recently, Granick and his research team work across disciplines to explore imaging, assembly, behavior and interactions of molecules, colloidal particles, and their assemblies.
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2D x-tal with thermal fluctuations of particle positions. Red lines symbolize lattice-axis and green arrows symbolize the deviations of equilibrium positions. The Image shows a (quasi-) two-dimensional crystal of colloidal particles. This are micrometer sized particles dispersed in water and sedimented on a flat interface thus they can perform Brownian motions only within a plane.
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P. Safonov, V.M. Shalaev, V.A. Markel, Yu.E. Danilova, N.N. Lepeshkin, W.Kim, S.G. Rautian, and R.L. Armstrong, Spectral Dependence of Selective Photomodification in Fractal Aggregates of Colloidal Particles, Physical Review Letters, v. 80, pp. 1102–1105 (1998)W. Kim, V.P. Safonov, V.M. Shalaev, and R.L. Armstrong, Fractals in Microcavities: Giant Coupled Multiplicative Enhancement of Optical Responses, Physical Review Letters, v.
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Colloidal semiconductor nanocrystals are synthesized from solutions, much like traditional chemical processes. The main difference is the product neither precipitates as a bulk solid nor remains dissolved. Heating the solution at high temperature, the precursors decompose forming monomers which then nucleate and generate nanocrystals. Temperature is a critical factor in determining optimal conditions for the nanocrystal growth.
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Prieve, Dennis C., and Nasser A. Frej. "Total internal reflection microscopy: a quantitative tool for the measurement of colloidal forces." Langmuir 6.2 (1990): 396-403. Since the penetration depth of the evanescent field is on the order of hundreds of nanometers, this technique is among the most sensitive for tracking displacements in the direction perpendicular to a surface.
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Microfilled fillers are made of colloidal silica with a particle size of 0.4 µm. Resin with this type of filler is easier to polish compared to macrofilled. However, its mechanical properties are compromised as filler load is lower than in conventional (only 40-45% by weight). Therefore, it is contraindicated for load-bearing situations, and has poor wear resistance.
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Surface plasmon resonance can also be tuned based on the shape of the nanoparticle. The plasmon frequency can be related to the metal dielectric constant. The enhancement falls off quickly with distance from the surface and, for noble metal nanoparticles, the resonance occurs at visible wavelengths. Localized surface plasmon resonance creates brilliant colors in metal colloidal solutions.
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Flow velocity is especially critical for hard water or liquids containing suspensions in preventing excessive fouling. Higher cross-flow velocities can be used to enhance the sweeping effect across the membrane surface therefore preventing deposition of macromolecules and colloidal material and reducing the effects of concentration polarization. Expensive pumps are however required to achieve these conditions.
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Cranberry glass, while it looks homogeneous, is a mixture consisting of glass and gold colloidal particles of ca. 40 nm diameter, which give it a red color. All matter consists of various elements and chemical compounds, but these are often intimately mixed together. Mixtures contain more than one chemical substance, and they do not have a fixed composition.
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This is a process known as syneresis. A small amount of water can be seen on top of the gel. Retrogradation is directly related to the staling or aging of bread.Cereals in breadmaking: a molecular colloidal approach, Ann-Charlotte Eliasson, Kåre Larsson, CRC Press, 1993, pages: 126-129, , Retrograded starch is less digestible (see resistant starch).
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Examples are starch, cellulose, and glycogen. They are generally large and often have a complex branched connectivity. Because of their size, polysaccharides are not water- soluble, but their many hydroxy groups become hydrated individually when exposed to water, and some polysaccharides form thick colloidal dispersions when heated in water. Shorter polysaccharides, with 3 - 10 monomers, are called oligosaccharides.
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Sachiko Kodama (born 1970) is a Japanese artist. She is best known for her artwork using ferrofluid, a dark colloidal suspension of magnetic nano- particles dispersed in solution which remains strongly magnetic in its fluid. By controlling the fluid with a magnetic field, it is formed to create complex 3-dimensional shapes as a "liquid sculpture".
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In this theory the depletion force arises from an increase in osmotic pressure of the surrounding solution when colloidal particles get close enough such that the excluded cosolutes (depletants) cannot fit in between them. Because the particles were considered as hard-core (completely rigid) particles, the emerging picture of the underlying mechanism inducing the force was necessarily entropic.
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Some wine production methods also use depletion forces to remove dispersed particles from wine. Unwanted colloidal particles can be found in wine originating from the must or produced during the winemaking process. These particles typically consist of carbohydrates, pigmentation molecules, or proteins which may adversely affect the taste and purity of the wine.Moreno, Juan; Peinado, Rafael.
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In order to provide optimal performance, pigment particles must act independently of each other in the coating film and thus must remain well dispersed throughout manufacture, storage, application, and film formation. Unfortunately, colloidal dispersions such as the pigment dispersions in liquid coatings are inherently unstable, and they must be stabilized against the flocculation that might occur.
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Colloidal micro-lenses have also enabled single molecule detection when used in conjunction with a long working distance, low light collection efficiency objective lens. Micro- lens arrays are also used by Lytro to achieve light field photography (plenoptic camera) that eliminates the need for initial focusing prior to capturing images. Instead, focus is achieved in software during post- processing.
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Lipids, used by all living organisms, are one example of molecules able to form either emulsions (e.g: spherical micelles; Lipoproteins) or liquid crystals (lipid bilayer membranes). The term "emulsion" is also used to refer to the photo-sensitive side of photographic film. Such a photographic emulsion consists of silver halide colloidal particles dispersed in a gelatin matrix.
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In autumn 1895, he returned to the University of Leipzig as an assistant to Wilhelm Ostwald. The two men had much in common, including interests in pacifism and internationalism. In 1898 Bredig discovered that it is possible to make colloidal solutions of metals usable as catalysts. Bredig's arc method became the preferred chemical method of creating metallic solutions.
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Copper monosulfide is a chemical compound of copper and sulfur. It occurs in nature as the dark indigo blue mineral covellite. It is a moderate conductor of electricity.Wells A.F. (1962) Structural Inorganic Chemistry 3d edition Oxford University Press A black colloidal precipitate of CuS is formed when hydrogen sulfide, H2S, is bubbled through solutions of Cu(II) salts.
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The term may also be applied to other granular materials. This is different from the crystallite size, which refers to the size of a single crystal inside a particle or grain. A single grain can be composed of several crystals. Granular material can range from very small colloidal particles, through clay, silt, sand, gravel, and cobbles, to boulders.
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Inorganic substances such as colloidal ferric chloride or molybdenum compounds supposedly acted as cofactors and catalysts. Bahadur also reported having detected ATPase-like and peroxidase-like activity. Bahadur stated that by using molybdenum as a cofactor, the Jeewanu showed capability of reversible photochemical electron transfer, and released a gas mixture of oxygen and hydrogen at a 1:2 ratio.
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Soil biota can treat waste by transforming it. Soil organic matter and soil minerals can adsorb the waste material and decrease its toxicity, although when in colloidal form they may transport the adsorbed contaminants to subsurface environments. Many waste treatment processes rely on this natural bioremediation capacity. Exceeding treatment capacity can damage soil biota and limit soil function.
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Moreover, Paclitaxel has been used in vitro to inhibit insulin fibrillation; in a molar ratio of 10:1 (insulin:paclitaxel), it hindered insulin fibrillation near 70%. Iso- thermal titration calorimetry (ITC) findings indicated a spontaneous tendency of paclitaxel to interact with insulin through hydrogen bonds and van der Waal's forces. Also, the inhibitory role of paclitaxel is attributed to its impact on the colloidal stability of protein solution, as it was observed that paclitaxel inhibited lysozyme fibrillation by inducing the formation of "off- pathway" oligomeric intermediates and increasing the colloidal stability subsequently. Paclitaxel is sometimes used for in vivo studies as well; it can be fed to test organisms, such as fruit flies, or injected into individual cells, to inhibit microtubule disassembly or to increase the number of microtubules in the cell.
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The special three-layered glass sheets (milky white, crystal clear, and ruby) were manufactured by the Gus-Khrustalny glass factory. The ruby layer of the sheets is colored by adding colloidal gold to the glass. Machinery that services the Kremlin stars are located inside the towers. Special lifting devices allow for periodic cleaning of the stars inside and out, removing dust and soot.
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Indirect techniques. As many properties of colloidal suspensions depend on the state of aggregation of the suspended particles, various indirect techniques have been used to monitor particle aggregation too. While it can be difficult to obtain quantitative information on aggregation rates or cluster properties from such experiments, they can be most valuable for practical applications. Among these techniques settling tests are most relevant.
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She worked for a time at Cambridge on problems of regeneration and osmotic phenomena in muscle, and this led her to a study of osmotic phenomena in simpler non-living colloidal systems. Her researches were interrupted by the First World War when she investigated – for the Medical Research Committee – substitute culture media for bacteriology, and the causes and prevention of ropiness in bread.
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Ligands are small, usually organic molecules that bind to the surface of particles, preventing seeds from further growth. Ligands are necessary as they increase the energy barrier of coagulation, preventing agglomeration. The balance between attractive and repulsive forces within colloidal solutions can be modeled by DLVO theory. Ligand binding affinity, and selectivity can be used to control shape and growth.
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A colloidal crystal is an ordered array of colloid particles and fine grained materials analogous to a standard crystal whose repeating subunits are atoms or molecules. A natural example of this phenomenon can be found in the gem opal, where spheres of silica assume a close-packed locally periodic structure under moderate compression.Darragh, P.J., et al., Opal, Scientific American, Vol.
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Colloidal nanocrystals are a new class of optical materials that essentially constitute a new form of matter that can be considered as "artificial atoms." Like atoms, they have discrete optical energy spectra that are tunable over a wide range of wavelengths. The desired behavior and transmission directly correlates to their size. To change the emitted wavelength, the crystal is grown larger or smaller.
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Sporadically, epithelial follicles containing colloidal material can be found. The organ is surrounded by a dense, perineurium-like connective tissue. Originally, the formation was known to embryologists only ("Chievitz Organ") and was considered to be a transient rudimentary structure, disappearing before birth. In 1953, Wolfgang Zenker proved that the formation shows further development and can be found in adult humans with regularity.
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His research has involved study of molecular and interfacial forces. His work is applicable to a wide range of industrial and fundamental science problems. In particular, he has contributed significantly to the understanding of colloidal dispersions, biological systems, and polymer engineering applications. He has studied interfacial phenomena, the physics of thin films, and fundamental questions in rheology and tribology of surfaces.
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Thin film composites membranes typically suffer from compaction effects under pressure. As the water pressure increases, the polymers are slightly reorganized into a tighter fitting structure that results in a lower porosity, ultimately limiting the efficiency of the system designed to use them. In general, the higher the pressure, the greater the compaction. Surface fouling: Colloidal particulates, bacteria infestation (biofouling).
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Further, functionalizing the surface of solid lipid nanoparticles with polyethylene glycol (PEG) can result in increased BBB permeability. Different colloidal carriers such as liposomes, polymeric nanoparticles, and emulsions have reduced stability, shelf life and encapsulation efficacy. Solid lipid nanoparticles are designed to overcome these shortcomings and have an excellent drug release and physical stability apart from targeted delivery of drugs.
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Egon Matijevic (27 April 1922 – 20 July 2016) was an American chemist. He earned his B.Sc. and Ph.D. in chemistry from the University of Zagreb. After specialization at the University of Cambridge he continued to work at the Clarkson University. He is the author of more than 550 scientific papers in colloidal and surface chemistry with numerous applications in medicine and industry.
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Clay Cutans form by the coating of ancient open spaces by colloidal materials that were eluviated down from overlying horizons - and are commonly stained by iron oxides such as hematite. While the originally openings are commonly lost through geologic time and diagenesis, the cutanic fabric remains as evidence. Cutans also often contain relics of nodules and skeleton grains. Retallack, G.J., 1988.
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Beer will develop an off-flavor during storage because of many factors, including sunlight and the amount of oxygen in the headspace of the bottle. Other than changes in taste, beer can also develop visual changes. Beer can become hazy during storage. This is called colloidal stability (haze formation) and is typically caused by the raw materials used during the brewing process.
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Water is polar, thus emulsifiers are needed for dispersion of fat. Also ice cream has a colloidal phase of foam which helps in its light texture. Milk proteins such as casein and whey protein present in ice cream are amphiphilic, can adsorb water and form micelles which will contribute to its consistency. The proteins contribute to the emulsification, aeration and texture.
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The properties of these suspensions depend on Hamaker theory and Van der Waals forces and can be stabilized electrostatically or sterically. Shear thickening behavior occurs when a colloidal suspension transitions from a stable state to a state of flocculation. A large portion of the properties of these systems are due to the surface chemistry of particles in dispersion, known as colloids.
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The addition of DNA to the surface of a quantum dot changes the intermolecular forces that occur between un-conjugated quantum dots. Changing the intermolecular forces between the quantum dots can alter many characteristics important for the use of quantum dots in aqueous conditions. As the surface of quantum dots are conjugated with DNA, the colloidal stability and solubility are affected.
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Margaret Barnes (26 August 1919 - 30 October 2009) was a British marine biologist. She was born in Manchester and grew up in Wales and England. She received a BSc from the University of London in 1939. Originally trained in chemistry, during World War II, she worked on colloidal graphite lubricants. She received a MSc in 1945 from the University of London.
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However, the level of silver in the air and the length of exposure that caused argyria in these workers is not known. Historically, colloidal silver, a liquid suspension of microscopic silver particles, was also used as an internal medication to treat a variety of diseases. In the 1940s, they were overtaken by the use of pharmaceutical antibiotics, such as penicillin.
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Several chemists suspected it to be a gold tin compound, due to its preparation. Faraday recognized that the color was actually due to the miniature size of the gold particles. He noted the light scattering properties of suspended gold microparticles, which is now called Faraday-Tyndall effect. In 1898, Richard Adolf Zsigmondy prepared the first colloidal gold in diluted solution.
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Aquadag is a trade name for a water-based colloidal graphite coating commonly used in cathode ray tubes (CRTs). It is manufactured by Acheson Industries, a subsidiary of ICI. The name is a shortened form of "Aqueous Deflocculated Acheson Graphite", but has become a generic term for conductive graphite coatings used in vacuum tubes. Other related products include Oildag, Electrodag and Molydag.
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Aquadag consists of a dispersion of colloidal graphite in distilled water. It is provided in concentrated paste form and is usually diluted with distilled water to a desired consistency before application. It can be applied by brushing, swabbing, spraying, or dipping, after which the surface is dried, leaving a layer of pure graphite. After drying the coating is electrically conductive.
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Adenosine triphosphate is a highly metastable molecule, colloquially described as being "full of energy" that can be used in many ways in biology. Generally speaking, emulsions/colloidal systems and glasses are metastable e.g. the metastability of silica glass is characterised by lifetimes of the order of 1098 years M.I. Ojovan, W.E. Lee, S.N. Kalmykov. An introduction to nuclear waste immobilisation.
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The step at which the densifier is applied is determined by hydration of the slab. There are many types of densifiers including, sodium, potassium, lithium, magnesium fluorosilicate and colloidal. # The densifier is allowed to dry and cure until proper hardness has been achieved, followed by one or more abrasive cuts, which will refine the floor to the desired level of reflectivity.
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This increases the operating costs of a treatment plant. There are various types of foulants: colloidal (clays, flocs), biological (bacteria, fungi), organic (oils, polyelectrolytes, humics) and scaling (mineral precipitates).Baker, R.W. (2004). Membrane Technology and Applications, England: John Wiley & Sons Ltd Fouling can be divided into reversible and irreversible fouling based on the attachment strength of particles to the membrane surface.
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His has a mattress made from organic materials and coated the walls of his apartment with colloidal silver paint, an antibacterial product which he believes protects him from the electromagnetic fields produced by WiFi. In 2017, Marone Cinzano was invited as a speaker to a TED conference in Kings College, London to discuss health and well-being in the living space.
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Gold clusters in cluster chemistry are gold-derived materials that can either be discrete molecules or larger colloidal particles. Both types are described as nanoparticles, with diameters of less than one micrometer. A nanocluster is a collective group made up of a specific number of atoms or molecules held together by some interaction mechanism. Gold nanoclusters have potential applications in optoelectronics and catalysis.
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031505 He then contributed and successfully illustrated how physico-chemistry skills could contribute to the understanding of cell biology by studying the case of colloidal objects interacting with cells (adhesion – internalization of artificial "viruses").P. Chenevier, et al., « Grafting molecular adresses onto biological vectors by alpha-oxohydrazone ligation : chemical caractérisation and biological efficiency », J. Am. Chem. Soc., 125, (2003), p. 52D.
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C. Hamaker, Physica, 4(10), 1058-1072 (1937) who also worked at Philips. However, the details on the repulsion produced by the electric double layer around colloidal particles were not so clear. By using thermodynamic considerations, the relevant free energies were calculated and interaction potential were derived. This research resulted in a seminal work Theory of the Stability of Lyophobic Colloids.
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Deposition of particles (grey) on a planar substrate (blue). Initial stages of particle deposition (top), blocking (middle), ripening (bottom) Particle deposition is the spontaneous attachment of particles to surfaces. The particles in question are normally colloidal particles, while the surfaces involved may be planar, curved, or may represent particles much larger in size than the depositing ones (e.g., sand grains).
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Removing coagulum from coagulating troughs. Latex coagulates in the cups if kept for long and must be collected before this happens. The collected latex, "field latex", is transferred into coagulation tanks for the preparation of dry rubber or transferred into air-tight containers with sieving for ammoniation. Ammoniation preserves the latex in a colloidal state for longer periods of time.
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Van Blaaderen was born on 27 October 1963 in Naarden. He attended the Voorbereidend wetenschappelijk onderwijs and subsequently studied physics and chemistry at Utrecht University. In 1992 he obtained his PhD at Utrecht University under professor A. Vrij with a dissertation titled Colloidal dispersions of (organo-)silica spheres: formation mechanism, structure and dynamics. In 1999 he was named professor of experimental physics of condensed matter.
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Small unilamellar vesicles (SUVs) can be made by sonication of a dispersion of large multilamellar vesicles (LMVs). Sonication is also used to fragment molecules of DNA, in which the DNA subjected to brief periods of sonication is sheared into smaller fragments. Sonication is commonly used in nanotechnology for evenly dispersing nanoparticles in liquids. Additionally, it is used to break up aggregates of micron-sized colloidal particles.
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Hydro-Distillation Process in Extracting Of Agarwood Essential Oil. Herbal distillates, also known as floral waters, hydrosols, hydrolates, herbal waters, and essential waters, are aqueous products of hydrodistillation. They are colloidal suspensions of essential oils as well as water-soluble components obtained by steam distillation or hydrodistillation (a variant of steam distillation) from plants/herbs. These herbal distillates have uses as flavorings and cosmetics (skin care).
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After the completion of his Ph.D., he moved to the University of Chicago in Chicago, Illinois as a post-doctoral research assistant in the group of Prof. Dmitri Talapin. In 2009, Kovalenko published an article in Science describing the use of inorganic ligands on colloidal nanocrystals. Such an all-inorganic design of semiconductor nanocrystals had enabled their integration into diverse electronic and optoelectronic devices.
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The silver mirror reaction involves the conversion of silver nitrate to Ag(NH3)OH. Ag(NH3)OH is subsequently reduced into colloidal silver using an aldehyde containing molecule such as a sugar. The silver mirror reaction is as follows: :2(Ag(NH3)2)+ \+ RCHO + 2OH− → RCOOH + 2Ag + 4NH3. The size and shape of the nanoparticles produced are difficult to control and often have wide distributions.
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Because the solutes are charged ions they also increase the electrical conductivity of the solution. The increased ionic strength reduces the thickness of the electrical double layer around colloidal particles, and therefore the stability of emulsions and suspensions. The chemical identity of the ions added is also important in many uses. For example, fluoride containing compounds are dissolved to supply fluoride ions for water fluoridation.
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In the 1946 "Silent and Verbal Levels" diagram,Kendig, M., "Alfred Korzybski's 'An Extensional Analysis of the Process of Abstracting from an Electro-Colloidal Non-Aristotelian Point of View.'" General Semantics Bulletin, Autumn-Winter 1950-51, Numbers Four & Five. Institute of General Semantics, Lakeville, CT. pp. 9-10. the arrows and boxes denote ordered stages in human neuro-evaluative processing that happens in an instant.
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Wiley Blacwell A number of studies demonstrate that these natural products have anti-inflammatory, antioxidant, anti-itch, anti-irritant, and antiatherogenic activities.Koening, R.T., Dickman, J.R., Wise, M.L., Ji, L.L. (2011). "Avenanthramides Are Bioavailable and Accumulate in Hepatic, Cardiac, and Skeletal Muscle Tissue Following Oral Gavage in Rats". Journal of Agricultural and food chemistry, 6438–6443Kurtz, E.S.; Wallo, W. "Colloidal oatmeal: history, chemistry and clinical properties".
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The second methodology, the flotation technique, works best with finer sediments where the mass of the sediment particles is close to that of the meiofauna. The best solution to use is the colloidal silica, Ludox. The sample is stirred into the Ludox solution and left to settle for 40 min, after which the meiofauna are filtered out. In fine sediments, extraction efficiency is improved with centrifugation.
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Colloidal quantum dots are also used in inorganic/organic hybrid solar cells. These solar cells are attractive because of the potential for low-cost fabrication and relatively high efficiency. Incorporation of metal oxides, such as ZnO, TiO2, and Nb2O5 nanomaterials into organic photovoltaics have been commercialized using full roll-to-roll processing. A 13.2% power conversion efficiency is claimed in Si nanowire/PEDOT:PSS hybrid solar cells.
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Hash oil may be sold in cartridges used with pen vaporizers. Preparations of hash oil may be solid or colloidal depending on both production method and temperature and are usually identified by their appearance or characteristics. Color most commonly ranges from transparent golden or light brown, to tan or black. Cannabis retailers in California have reported about 40% of their sales are from cannabis oils.
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These transformations can result in the formation of colloidal solutions. Each of these new species potentially have toxic effects which have yet to be fully examined. Most silver nanoparticles in products have an organic shell structure around a core of Ag0. This shell is often created with carboxylic acids functional groups, usually using citrate, leading to stabilization through adsorption or covalent attachment of organic compounds.
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Casein has a wide variety of uses, from being a major component of cheese, to use as a food additive. The most common form of casein is sodium caseinate. In milk, casein undergoes phase separation to form colloidal casein micelles, a type of secreted biomolecular condensate. Micelle caseine As a food source, casein supplies amino acids, carbohydrates, and two essential elements, calcium and phosphorus.
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One of them proposes the micellar nucleus is formed by several submicelles, the periphery consisting of microvellosities of κ-casein. Another model suggests the nucleus is formed by casein-interlinked fibrils. Finally, the most recent model proposes a double link among the caseins for gelling to take place. All three models consider micelles as colloidal particles formed by casein aggregates wrapped up in soluble κ-casein molecules.
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Rob Duncan Coalson from the University of Pittsburgh, was awarded the status of Fellow in the American Physical Society, after they were nominated by their Division of Chemical Physics in 1999, for novel contributions to the theory of condensed phase quantum dynamics, including computational methodology and applications to optical spectroscopy and electron transfer; and for theoretical insights into macroion electrostatics, with applications to colloidal suspensions and crystals.
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Optical properties of colloidal suspensions depend on the suspended particles size and size distribution. Because formazine is a stable synthetic material with uniform particle size it is commonly used as a standard to calibrate turbidimeters and to control the reproducibility of their measurements. Formazin use was first proposed by Kingsbury et al. (1926) for the rapid standardization of turbidity measurements of albumin in urine.
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The shelf life of formazine dispersions does not exceed a few months (a few weeks if the bottle has been opened) as their characteristics evolve with time due to the ageing of the colloidal particles (Ostwald ripening: change in their size distribution and in their number due to their coalescence/aggregation) and the possible development of micro-organisms such bacteria, microscopic fungi, and yeast.
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Clay has been used throughout history as a form of dry shampoo. The Rhassoul clay, also known as red clay, originating from Morocco is traditionally used as a leave in shampoo and conditioner. Due to its high absorbance of sebum, clay is often used as a remedy for dandruff and seborrhea. Such properties of clay stem from its colloidal particle size and crystalline structure.
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Aqueous colloidal gold. Zsigmondy left organic chemistry to join the physics group of August Kundt at the University of Berlin, and completed his habilitation at the University of Graz in 1893. Because of his knowledge about glass and its colouring, in 1897 the Schott Glass factory offered him a job which he accepted. He invented the Jenaer Milchglas and conducted some research on the red Ruby glass.
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The medical profession, specifically orthopedic surgeons, use the term to refer to 3D printed titanium technology which is used to generate implantable medical devices. In a water-treatment context, lamellar filters may be referred to as plate filters or tube filters. This term is used to describe a certain type of ichthyosis, a congenital skin condition. Lamellar Ichthyosis often presents with a "colloidal" membrane at birth.
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Alkyl naphthalene sulfonates (ANS) are used in many industrial applications as nondetergent wetting agents that effectively disperse colloidal systems in aqueous media. The major commercial applications are in the agricultural chemical industry, which uses ANS for wettable powder and wettable granular (dry-flowable) formulations, and the textile and fabric industry, which utilizes the wetting and defoaming properties of ANS for bleaching and dyeing operations.
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Deflocculation refers to the distribution of powdered high purity graphite in an aqueous solution containing approximately 2% to 10% by weight of various Tannic/Gallotannic acid variants and separating the colloidal graphite suspension from the remaining unsuspended graphite particulates. The product names are often printed with DAG in upper case (e.g. AquaDAG). It is used as an electrically conductive coating on insulating surfaces, and as a lubricant.
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On the other hand, K. Ladavac et al. used a spatial light modulator to project an intensity pattern to enable the optical sorting process. K. Xiao and D. G. Grier applied holographic video microscopy to demonstrate that this technique can sort colloidal spheres with part-per-thousand resolution for size and refractive index. The main mechanism for sorting is the arrangement of the optical lattice points.
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The requirements for slab stabilization are strength and the ability to flow into or expand to fill small voids. Colloidal mixing equipment is necessary to use the pozzolan- cement grouts. The contractor must place the grout using a positive- displacement injection pump or a non-pulsing progressive cavity pump. A drill is also necessary but it must produce a clean hole with no surface spalling or breakouts.
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Some subset of DOC constitutes the precursors of disinfection byproducts for drinking water. BDOC can contribute to undesirable biological regrowth within water distribution systems. The dissolved fraction of total organic carbon (TOC) is an operational classification. Many researchers use the term "dissolved" for compounds that pass through a 0.45 μm filter, but 0.22 μm filters have also been used to remove higher colloidal concentrations.
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Equal-time spin–spin correlation functions are measured with neutron scattering as opposed to x-ray scattering. Neutron scattering can also yield information on pair correlations as well. For systems composed of particles larger than about one micrometer, optical microscopy can be used to measure both equal-time and equal-position correlation functions. Optical microscopy is thus common for colloidal suspensions, especially in two dimensions.
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Carbon bridge is a thin spot of colloidal graphite used as the bridgewire. Some variants use a conductive pyrotechnic composition as the resistive material. In amateur rocketry, grossly overloaded low wattage metal film resistors and 0805 Surface-mount technology resistors are also used. A shallow notch cut into the center of the bridgewire promotes gross localized overheating instead of homogeneous heating of the entire bridgewire.
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Mask preparation with the Langmuir-Blodgett method has been demonstrated for example using SiO2 particles and polystyrene particles. Dip Coating is a simplified version of the Langmuir-Blodgett. In dip coating, the nanosphere packing density isn't controlled but the dipping is performed directly on a colloidal particle solution. Dip coating is an effective method for applications where a precise control over the particle distribution isn't required.
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Mering published over 100 technical papers on X-ray and electron diffraction of clays and related layer silicates, and of carbon, graphite, and the phenomena involved in graphitisation. He also performed numerous experimental works on fine-grained materials, including crystal growth in gels, the crystalline organization in cellulose, the 'decoration' of kaolinite crystals with colloidal gold particles, clays as catalysts, montmorillonites, hectorite, and clay-organic complexes.
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Green liquor is the dissolved smelt of sodium carbonate, sodium sulfide and other compounds from the recovery boiler in the kraft process. The liquor's eponymous green colour arises from the presence of colloidal iron sulfide. The green liquor is usually reacted with lime (CaO) in the causticizing stage to regenerate white liquor. Alternatively, green liquor can be used prior to white liquor to extract some hemicellulose.
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A photograph and representative spectrum of photoluminescence from colloidal CdSe quantum dots excited by UV light. CdSe- derived nanoparticles with sizes below 10 nm exhibit a property known as quantum confinement. Quantum confinement results when the electrons in a material are confined to a very small volume. Quantum confinement is size dependent, meaning the properties of CdSe nanoparticles are tunable based on their size.
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Arthur Eichengrün invented this type of colloidal silver, which was marketed by Bayer from 1897 onward. The silver-based treatment was used until the first antibiotics came into use in the 1940s. The exact time of onset of gonorrhea as prevalent disease or epidemic cannot be accurately determined from the historical record. One of the first reliable notations occurs in the Acts of the (English) Parliament.
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The latter process is known as particle release and is often triggered by the addition of appropriate chemicals or a modification in flow conditions. Microorganisms may deposit to surfaces in a similar fashion as colloidal particles. When macromolecules, such as proteins, polymers or polyelectrolytes attach to surfaces, one rather calls this process adsorption. While adsorption of macromolecules largely resembles particle deposition, macromolecules may substantially deform during adsorption.
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A colloidal crystal is a highly ordered array of particles that can be formed over a very long range (typically on the order of a few millimeters to one centimeter) and that appear analogous to their atomic or molecular counterparts. One of the finest natural examples of this ordering phenomenon can be found in precious opal, in which brilliant regions of pure spectral color result from close-packed domains of amorphous colloidal spheres of silicon dioxide (or silica, SiO2). These spherical particles precipitate in highly siliceous pools in Australia and elsewhere, and form these highly ordered arrays after years of sedimentation and compression under hydrostatic and gravitational forces. The periodic arrays of submicrometre spherical particles provide similar arrays of interstitial voids, which act as a natural diffraction grating for visible light waves, particularly when the interstitial spacing is of the same order of magnitude as the incident lightwave.
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The lake was officially mentioned for the first time in the year 1075. The Tisza River regularly flooded the area up to the early 19th century. The lake once began to the typical brackish lakes of the Great Hungarian Plain. The common property of these shallow, salty lakes is that their water is cloudy from the colloidal lime salts and a greyish-white carbonic lime silt accumulates on the lakebed.
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Dye-sensitized solar cells are another related approach, but in this case the nano-structuring is part of the substrate. Previous fabrication methods relied on expensive molecular beam epitaxy processes, but colloidal synthesis allows for cheaper manufacture. A thin film of nanocrystals is obtained by a process known as "spin-coating". This involves placing an amount of the quantum dot solution onto a flat substrate, which is then rotated very quickly.
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This resulted in severe instability with respect to purification and washing, which was improved in 2018 with the introduction of zwitterionic ligands. The stability and quality of these colloidal materials was further improved in 2019 when it was demonstrated that deep traps could be generated by the partial destruction of the lead-halide octahedra, and that they could also be subsequently repaired to restore the quantum yield of nanocrystals.
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Juliette Roche, La minéralisation de Dudley Craving Mac Adam, Centre Pompidou In 1920-21 she wrote État... Colloidal, published by the Chilean journalist Vicente Huidobro in the magazine Creación.Sobre la revista Creación (Spanish) In 1927, together with Albert Gleizes, they founded the , a residence of artists in Sablons, which offered studios and workshops.Moly-Sabata / Fondation Albert Gleizes: Résidence d'artistes She continued to exhibit the rest of his life in group exhibitions.
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It can be used as a dry powder, in water or oil, or as colloidal graphite (a permanent suspension in a liquid). An estimate based on USGS graphite consumption statistics indicates that 2,200 tonnes was used in this fashion in 2005. Metal can also be impregnated into graphite to create a self-lubricating alloy for application in extreme conditions, such as bearings for machines exposed to high or low temperatures.
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The mesohyl is composed of the following main elements: collagen, fibronectin-like molecules, galectin, and a minor component, dermatopontin. These polypeptides form the extracellular matrix which provides the platform for specific cell adhesion as well as for signal transduction and cellular growth. The mesohyl includes a noncellular colloidal mesoglea with embedded collagen fibers, spicules and various cells, being as such a type of mesenchyme.Brusca, R.C. & Brusca, G.J. (2003). Invertebrates.
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The origins of colloidal crystals go back to the mechanical properties of bentonite sols, and the optical properties of Schiller layers in iron oxide sols. The properties are supposed to be due to the ordering of monodisperse inorganic particles. Monodisperse colloids, capable of forming long-range ordered arrays, existing in nature. The discovery by W.M. Stanley of the crystalline forms of the tobacco and tomato viruses provided examples of this.
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Crystalline thin-films from non-spherical colloids were produced using convective assembly techniques. Colloid shapes included dumbbell, hemisphere, disc, and sphero-cylinder shapes. Both purely crystalline and plastic crystal phases could be produced, depending on the aspect ratio of the colloidal particle. The low aspect ratio, such as bulge, eye-ball, and snowman-like non-spherical colloids, which spontaneously self-assembled to photonic crystal array with high uniformity.
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In 2003, colloidal oatmeal was officially approved as a skin protectant by the FDA. However, little thought had been given to the active ingredient in oats responsible for the anti-inflammatory effect until more attention was paid to avenanthramides, which were first isolated and characterized in the 1980s by Collins.Dimberg LH. Theander O, Lingnert H. "Avenanthramides - a group of phenolic antioxidants in oats". Cereal Chem. 1992;70:637–641.
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Chrysotype (also known as a chripotype or gold print) is a photographic process invented by John Herschel in 1842. Named from the Greek for "gold", it uses colloidal gold to record images on paper. Herschel's system involved coating paper with ferric citrate, exposing it to the sun in contact with an etching used as mask, then developing the print with a chloroaurate solution. This did not provide continuous-tone photographs.
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The Colloid Chemistry department, headed by Markus Antonietti, deals with the synthesis of various colloidal structures in the nanometer range. This includes inorganic and metallic nanoparticles, polymers and peptide structural units, their micelles and organised phases, as well as emulsions and foams. Colloid chemistry is able to create materials with a structural hierarchy through appropriate functionalized colloids. This creates new characteristics through the "teamwork" of the functional groups.
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When they vibrated the plate at critical amplitude, they found that the balls formed a localized vibrating structure when perturbed which lasted indefinitely. Oscillons have also been experimentally observed in thin parametrically vibrated layers of viscous fluid and colloidal suspensions. Oscillons have been associated with Faraday waves because they require similar resonance conditions. Nonlinear electrostatic oscillations on a plasma boundary can also appear in the form of oscillons.
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He explains that the only way to confirm his theory was by way of a gold indicator, (Tin(II) chloride), which reduces gold ions to colored colloidal gold. By applying the indicator to his hands and touching Maria's hand after she went to the bathroom, he confirms his suspicion that Maria was killing Bob with Sodium aurothiomalate. At the end, House erases a message from a realtor to Wilson.
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Concentration of Plasmodium falciparum-infected erythrocytes by discontinuous density gradient centrifugation in Percoll. Percoll is a tool for more efficient density separation in biochemistry that was first formulated by Pertoft and colleagues. It is used for the isolation of cells, organelles, and/or viruses by density centrifugation. Percoll consists of colloidal silica particles of 15–30 nm diameter (23% w/w in water) which have been coated with polyvinylpyrrolidone (PVP).
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James William McBain FRS (March 22, 1882 – March 12, 1953) was a Canadian chemist. He gained a Master of Arts at Toronto University and a Doctor of Science at Heidelberg University. He carried out pioneering work in the area of micelles at the University of Bristol. As early as 1913 he postulated the existence of "colloidal ions", now known as micelles, to explain the good electrolytic conductivity of sodium palmitate solutions.
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Aida received his Bachelor of Engineering in Colloidal Science at the Yokohama National University in 1979, before moving to the University of Tokyo for his Master of Engineering (1981) and Doctor of Engineering (1984) degrees in Polymer Chemistry. He was awarded the Inoue Research Award for Young Scientists for his doctoral work, with the thesis title of "Controlled Polymerization by Metalloporphyrins" under the supervision of Professor Shohei Inoue.
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The inverse of stiffness is flexibility or compliance, typically measured in units of metres per newton. In rheology, it may be defined as the ratio of strain to stress,V. GOPALAKRISHNAN and CHARLES F. ZUKOSKI; "Delayed flow in thermo-reversible colloidal gels"; Journal of Rheology; Society of Rheology, U.S.A.; July/August 2007; 51 (4): pp. 623–644. and so take the units of reciprocal stress, e.g. 1/Pa.
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Yuichi Negishi, Katsuyuki Nobusada, Tatsuya Tsukuda: "Glutathione-Protected Gold Clusters Revisited: Bridging the Gap between Gold(I)−Thiolate Complexes and Thiolate-Protected Gold Nanocrystals", J. Am. Chem. Soc., 2005, 127 (14), 5261–5270 (). Several synthesis recipes exist that are similar to the Brust synthesis of colloidal gold, however the mechanism is not yet fully understood. The synthesis produces a mixture of dissolved, thiolate-protected gold clusters of different sizes.
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Ice cream is a colloidal emulsion made with water, ice, milk fat, milk protein, sugar and air. Water and fat have the highest proportions by weight creating an emulsion that has dispersed phase as fat globules. The emulsion is turned into foam by incorporating air cells which are frozen to form dispersed ice cells. The triacylglycerols in fat are non polar and will adhere to themselves by Van der Waals interactions.
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The Svedberg (1884-1971),(Theodor), professor in physical chemistry at Uppsala University from 1912 to 1949, was awarded the Nobel Prize in chemistry in 1926Nobel prize. Retrieved Feb 2015 for his research on dispersed systems (colloidal solutions). He invented the Ultracentrifuge, which was used in the discovery that proteins consist of macromolecules. Towards the end of the 1930s The Svedberg and his colleagues built their first accelerator, a Neutron generator.
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This equation is used to find the zeta potential, which is calculated to find the electrokinetic potential in colloidal dispersions. Through electrostatic interactions the casein molecules begin approaching and aggregating together. The casein proteins enter a more ordered system, attributing to a strong gel structure formation. The whey proteins that were denatured in the heating steps of processing, are insoluble at this acidic pH and are precipitated with casein.
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Solid lipid nanoparticles have recently materialized as a novel approach to oral and parenteral drug delivery systems. SLNs combine the advantages of lipid emulsion and polymeric nanoparticle systems while overcoming the temporal and in vivo stability issues that troubles the conventional as well as polymeric nanoparticles drug delivery approaches (Mehnert et al., 2001). It has been proposed that SLNs combine numerous advantages over the other colloidal carriers i.e.
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In the constant compliance region, the lever deformation is given by : ξ = (S − S0)/a In this fashion, one can detect deflections of the cantilever with typical resolution of better than 0.1 nm. Response of the colloidal probe to different force profiles. The forces profiles are shown in top row, and the cantilever response in the bottom. From left to right: Hard-core repulsion, soft repulsion, and attraction.
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For nanowires, the best catalysts are liquid metal (such as gold) nanoclusters, which can either be self-assembled from a thin film by dewetting, or purchased in colloidal form and deposited on a substrate. The source enters these nanoclusters and begins to saturate them. On reaching supersaturation, the source solidifies and grows outward from the nanocluster. Simply turning off the source can adjust the final length of the nanowire.
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The cell was first discovered by Robert Hooke in 1665 using a microscope. The first cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s. In this theory the internal contents of cells were called protoplasm and described as a jelly- like substance, sometimes called living jelly. At about the same time, colloidal chemistry began its development, and the concepts of bound water emerged.
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Secondary treatment by biochemical oxidation of dissolved and colloidal organic compounds is widely used in sewage treatment and is applicable to some agricultural and industrial wastewaters. Biological oxidation will preferentially remove organic compounds useful as a food supply for the treatment ecosystem. Concentration of some less digestible compounds may be reduced by co-metabolism. Removal efficiency is limited by the minimum food concentration required to sustain the treatment ecosystem.
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In materials science, the sol–gel process is a method for producing solid materials from small molecules. The method is used for the fabrication of metal oxides, especially the oxides of silicon (Si) and titanium (Ti). The process involves conversion of monomers into a colloidal solution (sol) that acts as the precursor for an integrated network (or gel) of either discrete particles or network polymers. Typical precursors are metal alkoxides.
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Zeta potential is used as an indicator of colloidal stability, and has been shown to be predictive of nanoparticle uptake by cells. Zeta potential can be measured by titration to find the isoelectric point, or through electrophoresis including laser Doppler electrophoresis. Surface energy or wettability are also important for nanoparticle aggregation, dissolution, and bioaccumulation. They can be measured through heat of immersion microcalorimetry studies, or through contact angle measurements.
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Stickies that pass through a slotted plate screen of 0.10 - 0.15 mm are called micro stickies. Micro stickies can be finely dispersed (100 µm - 100 nm), colloidal (100 - 10 nm) or molecularly dissolved (< 10 nm). Macro stickies are those which are retained as screening residue. The reason for this classification is that macro stickies are easy to remove from the deinked pulp during the deinking process by means of filtration.
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However, even if photons have enough energy they usually do not have enough momentum to set the ripple in motion. Therefore, plasmons are hard to excite on a bulk metal. This is why gold and copper still look like lustrous metals albeit with a dash of color. However, in colloidal gold the metallic bonding is confined to a tiny metallic particle, preventing the oscillation wave of the plasmon from 'running away'.
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One major drawback to using B-72 is the difficulty of applying the acrylic resin as an adhesive, as is difficulty in manipulating the substance as a workable agent. The most suitable solvent for B-72 is acetone. Unlike cellulose nitrate, B-72 does not need additives like plasticizers to stabilize its durability. Fumed colloidal silica is a chemical that can be added to help with the workability of the resin.
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The Italians adopted it as filite, in cord instead of flake form, but realising its drawbacks changed to a formulation with nitroglycerine they called solenite. In 1891 the Russians tasked the chemist Mendeleev with finding a suitable propellant. He created nitrocellulose gelatinised by ether-alcohol, which produced more nitrogen and more uniform colloidal structure than the French use of nitro-cottonssmokeless powder in Poudre B. He called it pyrocollodion.
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Each layer is only sensitive to a certain color of visible light. In the classic illustrative example, there are three emulsions: one is red sensitive, another is green sensitive, and the top is blue-sensitive. Beneath the blue layer is a yellow filter, composed of dyes or colloidal silver. All silver-based photographic emulsions have some sensitivity to blue light, regardless of what other colors they may be sensitized for.
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A variety of inhibitors of tumor angiogenesis are being actively studied. These include both recombinant proteins derived from naturally occurring substances as well as small molecules designed to act on specific pathways. Various methods of delivering these agents, including gene therapy approaches and the use of tumor targeted nanoparticles are being pursued. Libutti was the first to administer TNF bound colloidal gold nanoparticles as targeted therapy to cancer patients.
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For more on synthesis of AuNPs for medical use, see Colloidal gold Other synthesis may include cell type targeting. A tumor consists of a multitude of cell types, and thus targeting a single type of cell is ineffective and potentially dangerous. At most, this type of targeting would only have a minor effect on killing the tumor. Tumors are constantly changing and thus phenotype targeting is rendered useless.
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The phenomenon of Brownian motion was observed by Robert Brown in the form of random zig-zag motion of pollen grains suspended in water. This kind of movement is found in all colloidal systems. Such random motion is visible under ultramicroscopes and for bigger particles even under ordinary microscopes. The Brownian motion becomes progressively less prominent, as the particles grow in size or the viscosity of the medium increases.
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For a colloidal system, the thermodynamic equilibrium state may be reached when the particles are in deep primary minimum. At primary minimum, attractive forces overpower the repulsive forces at low molecular distances. Particles coagulate and this process is not reversible. However, when the maximum energy barrier is too high to overcome, the colloid particles may stay in the secondary minimum, where particles are held together weaker than the primary minimum.
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A colloidal crystal is a highly ordered array of particles that forms over a long range (from a few millimeters to one centimeter in length); colloidal crystals have appearance and properties roughly analogous to their atomic or molecular counterparts. It has been known for many years that, due to repulsive Coulombic interactions, electrically charged macromolecules in an aqueous environment can exhibit long-range crystal-like correlations, with interparticle separation distances often being considerably greater than the individual particle diameter. Periodic arrays of spherical particles give rise to interstitial voids (the spaces between the particles), which act as a natural diffraction grating for visible light waves, when the interstitial spacing is of the same order of magnitude as the incident lightwave. In these cases in nature, brilliant iridescence (or play of colours) is attributed to the diffraction and constructive interference of visible lightwaves according to Bragg's law, in a matter analogous to the scattering of X-rays in crystalline solid.
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Boron W.F., Boulpaep E.L. (2012.) Medical Physiology: A Cellular and Molecular Approach, 2e. Saunders/Elsevier, Philadelphia, PA. Hydrostatic pressure within blood vessels tends to cause water to filter out into the tissue. This leads to a difference in protein concentration between blood plasma and tissue. As a result, the colloidal or oncotic pressure of the higher level of protein in the plasma tends to draw water back into the blood vessels from the tissue.
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Other systems like the nanocars, while not technically motors, are also illustrative of recent efforts towards synthetic nanoscale motors. Other non-reacting molecules can also behave as motors. This has been demonstrated by using dye molecules that move directionally in gradients of polymer solution through favorable hydrophobic interactions. Another recent study has shown that dye molecules, hard and soft colloidal particles are able to move through gradient of polymer solution through excluded volume effects.
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Krishnan earned her undergraduate degree at Anna University in Chennai. She moved to the United States for her graduate studies, where she joined the University of Michigan at Ann Arbor to work on genetic testing. Krishnan was an Alexander von Humboldt Foundation Fellow at TU Dresden, where she developed new techniques to trap colloidal nanoparticles and stretch DNA. In 2008 she was awarded a Marie Curie Fellowship and moved to ETH Zurich.
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The high pH of young alkali gel exudations often precludes the growth of mosses at the surface of concrete crack infilling. 2\. Maturation of the alkali gel: polymerisation and gelation by the sol–gel process. Condensation of silicate monomers or oligomers dispersed in a colloidal solution (sol) into a biphasic aqueous polymeric network of silicagel. divalent cations released by calcium hydroxide (portlandite) when the pH starts to slightly drop may influence the gelation process. 3\.
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Cadmium selenide quantum dots emit bright luminescence under UV excitation (He-Cd laser, for example). The color of this luminescence can be green, yellow or red depending on the particle size. Colloidal solutions of those particles are used for imaging of biological tissues and solutions with a fluorescence microscope. Cadmium is a component of some compound semiconductors, such as cadmium sulfide, cadmium selenide, and cadmium telluride, used for light detection and solar cells.
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Small-angle laser light scattering has provided information about spatial density fluctuations or the shape of growing crystal grains. In addition, confocal laser scanning microscopy has been used to observe crystal growth near a glass surface. Electro-optic shear waves have been induced by an ac pulse, and monitored by reflection spectroscopy as well as light scattering. Kinetics of colloidal crystallization have been measured quantitatively, with nucleation rates being depending on the suspension concentration.
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Hantz reactions are a class of pattern-forming precipitation reactions in gels implementing a reaction-diffusion system. The precipitation patterns are forming as a reaction of two electrolytes: a highly concentrated "outer" one diffuses into a hydrogel, while the "inner" one is dissolved in the gel itself. The colloidal precipitate which builds up the patterns is trapped by the gel and kept at the location where it is formed. , similar to the Liesegang rings.
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He worked with the United States Bureau of Reclamation and later with Brock & Weymouth, an aerial photography company. Jeanne received a B.A. in chemistry from American University in Washington, D.C. She married Robert Clowe Burbank, also a chemist, on July 1, 1936. They worked at Peacock Laboratories in Philadelphia and studied colloidal chemistry at the University of Pennsylvania, from which Jeanne received her M.S. degree. Their daughter, Carey Lea Burbank, was born in 1942.
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Electrical double layer (EDL) around a negatively charged particle in suspension in water. The point of zero charge (pzc) is generally described as the pH at which the net charge of total particle surface (i.e. absorbent's surface) is equal to zero, which concept has been introduced in the studies dealt with colloidal flocculation to explain pH affecting the phenomenon. A related concept in electrochemistry is the electrode potential at the point of zero charge.
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Interactions between various objects were studied within the DH and PB models by many researchers. Some of the relevant results are summarized in the following. Non-planar geometries: Objects of other than planar geometries can be treated within the Derjaguin approximation, provided their size is substantially larger than the Debye length. This approximation has been used to estimate the force between two charged colloidal particles as shown in the first figure of this article.
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It is marketed by GlaxoSmithKline under the trade names Valtrex and Zelitrex. Valaciclovir has been available as a generic drug in the U.S. since November 25, 2009. Valtrex is offered in 500 mg and 1 gram tablets, with the active ingredient valacyclovir hydrochloride. The inactive ingredients include carnauba wax, colloidal silicon dioxide, crospovidone, FD&C; Blue No. 2 Lake, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone, and titanium dioxide.
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Peter Tsou with a sample of aerogel at Jet Propulsion Laboratory, California Institute of Technology. Silica aerogels are typically synthesized by using a sol-gel process. The first step is the creation of a colloidal suspension of solid particles known as a "sol". The precursors are a liquid alcohol such as ethanol which is mixed with a silicon alkoxide, such as tetramethoxysilane (TMOS), tetraethoxysilane (TEOS), and polyethoxydisiloxane (PEDS) (earlier work used sodium silicates).
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Other diamine compounds like DABCO do not share this selectivity. C60 but not C70 forms a 1:2 inclusion compound with cyclodextrin (CD). A separation method for both fullerenes based on this principle is made possible by anchoring cyclodextrin to colloidal gold particles through a sulfur-sulfur bridge. The Au/CD compound is very stable and soluble in water and selectively extracts C60 from the insoluble mixture after refluxing for several days.
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Although immunogold labeling is typically used for transmission electron microscopy, when the gold is 'silver-enhanced' it can be seen using brightfield microscopy. The silver enhancement increases the particle size, also making scanning electron microscopy possible. In order to produce the silver-enhanced gold particles, colloidal gold particles are placed in an acidic enhancing solution containing silver ions. Gold particles then act as a nucleation site and silver is deposited onto the particle.
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To proceed with her studies, she declined a research offer from Sjögren. Advised by Friedrich Fichter from the University of Basel, Sahlbom completed her thesis, an investigation on a capillary analysis of colloidal solutions. In 1910 Sahlbom presented the thesis at the University of Neuchâtel, and she earned a doctorate in chemical physics. In 1914, with input from Helge Backlund, Sahlbom set up a laboratory in Stockholm, where she specialized in aqueous mineralogy.
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Platinum nanoparticles are usually in the form of a suspension or colloid of nanoparticles of platinum in a fluid, usually water. A colloid is technically defined as a stable dispersion of particles in a fluid medium (liquid or gas). Spherical platinum nanoparticles can be made with sizes between about 2 and 100 nanometres (nm), depending on reaction conditions. Platinum nanoparticles are suspended in the colloidal solution of brownish-red or black color.
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The possibility to measure forces involving particles and surfaces directly is essential since such forces are relevant in a variety of processes involving colloidal and polymeric systems. Examples include particle aggregation, suspension rheology, particle deposition, and adhesion processes. One can equally study similar biological phenomena, such as deposition of bacteria or the infection of cells by viruses. Forces are equally most informative to investigate the mechanical properties of interfaces, bubbles, capsules, membranes, or cell walls.
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They often have bluish color owing to the presence of colloidal Li. This color can be removed by post-growth annealing at lower temperatures (~550 °C) and lower thermal gradients. Major impurities in these crystals are Na (20–200 parts per million, ppm), O (10–100 ppm), Mg (0.5–6 ppm), Fe (0.5-2 ppm) and Cu (0.5-2 ppm). Cracking in cast LiH after machining with a fly cutter. Scale is in inches.
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Thixotropy has been proposed as a scientific explanation of blood liquefaction miracles such as that of Saint Januarius in Naples.Garlaschelli, Ramaccini, Della the swagg fights of air forces Sala, "The Blood of St. Januarius", Chemistry in Britain 30.2, (1994:123) Other examples of thixotropic fluids are gelatine, shortening, cream, xanthan gum solutions, aqueous iron oxide gels, pectin gels, hydrogenated castor oil, carbon black suspension in molten tire rubber, many floc suspensions, and many colloidal suspensions.
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It is the largest component of some popular commercial firefighting products.Phos- Chek MSDS, Phos-Chek website DAP is also used as a yeast nutrient in winemaking and mead-making; as an additive in some brands of cigarettes purportedly as a nicotine enhancer; to prevent afterglow in matches, in purifying sugar; as a flux for soldering tin, copper, zinc and brass; and to control precipitation of alkali-soluble and acid-insoluble colloidal dyes on wool.
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In cancer research, colloidal gold can be used to target tumors and provide detection using SERS (surface enhanced Raman spectroscopy) in vivo. These gold nanoparticles are surrounded with Raman reporters, which provide light emission that is over 200 times brighter than quantum dots. It was found that the Raman reporters were stabilized when the nanoparticles were encapsulated with a thiol-modified polyethylene glycol coat. This allows for compatibility and circulation in vivo.
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Fumed colloidal silica can be added to help with the workability of the resin. Research shows that the silica better distributes the stress and strain that occurs during evaporation of a solvent and during the setting of the adhesive film. Because of its transparency and versatility, conservators, led by Stephen Koob of the Corning Museum of Glass, have recently begun to use cast sheets of B-72 as a fill material in glass objects.
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Lepidoptera that enter caves for sleeping are preyed upon by troglobitic Orthoptera, largely Tettigoniidae and Gryllidae. The cavernicolous Collembola feed on colloidal matter in the water or dust borne on the surface tension. The insects and similarly sized invertebrates are food for spiders and Myriapoda. Most such activities go on in darkness, except close to the outside, or where certain microbes or insects such as Arachnocampa provide bioluminescence, even if only to attract prey.
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One should be careful nor to use too much water since part of the precipitate may be lost. Also, in case of colloidal precipitates we should not use water as a washing solution since peptization would occur. In such situations dilute nitric acid, ammonium nitrate, or dilute acetic acid may be used. Usually, it is a good practice to check for the presence of precipitating agent in the filtrate of the final washing solution.
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He first learned of ceramic pot filters from its inventor Guatemalan chemist Fernando Mazariegos. Rivera produced this inexpensive filter developed in Guatemala by Mr. Mazariegos from a mix of local terra-cotta clay and sawdust or other combustible materials, such as rice husks. The combustible ingredient, which has been milled and screened, burns out in the firing, leaving a network of fine pores. After firing, the filter is coated with colloidal silver.
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After that, he went to work as a Miller Postdoctoral Fellow with A. Paul Alivisatos at the University of California, Berkeley. At Berkeley, he worked on electronic property and assembly of colloidal nanostructures. In 2005, he joined the Department of Materials Science and Engineering at Stanford University as an assistant professor and started to pursue energy and environment-related research. He was granted tenure in 2010 and promoted to full professor in 2016.
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To facilitate the filtration, the colloidal suspension must be first flocculated by adding a concentrated solution of salt to the system. Multivalent cations are more efficient flocculants than monovalent cations: AlCl3 > CaCl2 > NaCl. The electrical charges present at the surface of the particles are so "neutralised" and disappear. More correctly speaking, the electrical double layer existing at the surface of the particles is compressed by the added electrolyte and collapses at high ionic strength.
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Zeta potential titration is a titration of heterogeneous systems, for example colloids and emulsions. Solids in such systems have very high surface area. This type of titration is used to study the zeta potential of these surfaces under different conditions. Details of zeta potential definition and measuring techniques can be found in the International Standard International Standard ISO 13099-1, 2012, "Colloidal systems – Methods for Zeta potential determination- Part 1: Electroacoustic and Electrokinetic phenomena".
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In colloidal and surface chemistry, the critical micelle concentration (CMC) is defined as the concentration of surfactants above which micelles form and all additional surfactants added to the system will form micelles. The CMC is an important characteristic of a surfactant. Before reaching the CMC, the surface tension changes strongly with the concentration of the surfactant. After reaching the CMC, the surface tension remains relatively constant or changes with a lower slope.
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Lidija Liepiņa (, ; 4 April 1891 – 4 September 1985) was a Latvian chemist, and one of the first women to receive a doctorate in chemistry in Russia. Known for her research in colloidal chemistry. She lived in Russia until after World War II and then moved to Latvia for the remainder of her life. As a student, she helped create the first Russian gas mask and later published her theories about gas adsorption.
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Typically such structures are used for difficult-to-treat waters, especially those containing colloidal materials. Tube settlers capture the fine particles allowing the larger particles to travel to the bottom of the clarifier in a more uniform form. The fine particles then build up into a larger mass which then slides down the tube channels. The reduction in solids present in the outflow allows a reduction in the clarifier footprint when designing.
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Under normal conditions, acidification of solutions of this salt excess with even dilute acids results in complete decomposition to sulfur, sulfur dioxide, and water: : This reaction is known as a "clock reaction", because when the sulfur reaches a certain concentration, the solution turns from colorless to a pale yellow. This reaction has been employed to generate colloidal sulfur. This process is used to demonstrate the concept of reaction rate in chemistry classes.
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Their particles each have an electric charge which is attracted to the oppositely charged particles of the colloidal dispersion that they are breaking. The result is that the two substances become bound as a stable complex; their net charge becoming neutral. Thus the agglomeration of a semi-solid follows, which may be separated from the beverage either as a floating or settled mass. The only adsorbent types of finings in use are activated carbon and specialized fining yeasts.
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Materials are specifically described as "substances in the condensed states (liquid, solid, colloidal)", and which are "designed or manipulated for technological ends." Furthermore, Nature Materials functions as a forum for the materials scientist community. Interdisciplinary research results are published, obtained from across all areas of materials research, and between scientists involved in the different disciplines. The readership for this journal are scientists, in both academia and industry involved in either developing materials or working with materials-related concepts.
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220px Liquid marbles are non-stick droplets (normally aqueous) wrapped by micro- or nano-metrically scaled hydrophobic, colloidal particles (Teflon, polyethylene, lycopodium powder, carbon black, etc.); representing a platform for a diversity of chemical and biological applications. Liquid marbles are also found naturally; aphids convert honeydew droplets into marbles. A variety of non-organic and organic liquids may be converted into liquid marbles. Liquid marbles demonstrate elastic properties and do not coalesce when bounced or pressed lightly.
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The concept of dialysis was introduced in 1861 by a British chemist, Thomas Graham. He used this technique to separate sucrose (small molecule) and gum Arabic solutes (large molecule) in aqueous solution. He called the diffusible solutes crystalloids and those that would not pass the membrane colloids. From this concept dialysis can be defined as a spontaneous separation process of suspended colloidal particles from dissolved ions or molecules of small dimensions through a semi permeable membrane.
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Particle agglomeration refers to formation of assemblages in a suspension and represents a mechanism leading to the functional destabilization of colloidal systems. During this process, particles dispersed in the liquid phase stick to each other, and spontaneously form irregular particle assemblates, flocs, or agglomerates. This phenomenon is also referred to as coagulation or flocculation and such a suspension is also called unstable. Particle agglomeration can be induced by adding salts or other chemicals referred to as coagulant or flocculant.
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Ferrofluid mirrors are cheaper in terms of material cost, and are able to make more corrections due to its larger range of motion. The limitations associated with the use of mercury for deformable liquid mirrors can be solved through the use of ferrofluids. Ferrofluids are liquids that contain a suspension of colloidal ferromagnetic particles within a carrier liquid. In the presence of an external magnetic field, the ferromagnetic particles align with the field and the liquid becomes magnetized.
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She is the recipient of the Ladislaus Laszt Award of Ben-Gurion University (1995) for her book Biologists under Hitler and the recipient of the Gmelin Beilstein Medal of the Society of German Chemical Society (2005) for her book Flee, Collaborate, Forget. In 2011, she was the recipient of the Outstanding Paper Award from the Division of the History of Chemistry of the American Chemical Society for her article “‘Molecular’ versus ‘Colloidal’: Controversies in Biology and Biochemistry, 1900-1940”.
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In systems where forces of attraction forces are buffered to some degree, a balance of forces leads to an equilibrium phase separation, that is particles coexist with equal chemical potential in two distinct structural phases. The role of the ordered phase as an elastic colloidal solid has been evidenced by the elastic (or reversible) deformation due to the force of gravity. This deformation can be quantified by the distortion of the lattice parameter, or inter-particle spacing.
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Here, he built up an active research group in drug delivery systems. Davis took the position of Lord Trent Professor of Pharmacy at the University of Nottingham in 1975, where he ran a large research group, studying novel drug delivery systems. Topics of research have included drug targeting (with particular emphasis on colloidal carriers), transmucosal delivery, oral and parenteral systems for controlled release and product evaluation through gamma scintigraphy. He became an emeritus professor in 2003.
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The structure of carbon nanoscrolls is similar to that of a multi-walled carbon nanotube, but with a spiral-like rolled-up geometry and open edges at the ends. A number of methods have been reported to produce carbon nanoscrolls, including arc discharge, high-energy ball milling, and intercalation, among others. The wedge based mechanical exfoliation is also reported the similar CNS experimentally. However, the real world applications of nanoscroll products are limited due to their difficult colloidal processing.
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The pzc is typically obtained by acid-base titrations of colloidal dispersions while monitoring the electrophoretic mobility of the particles and the pH of the suspension. Several titrations are required to distinguish pzc from iep, using different electrolytes (including varying the electrolyte ionic strength). Once satisfactory graphs are obtained (acid/base amount—pH, and pH—zeta potential), the pzc is established as the common intersection point (cip) of the lines. Therefore, pzc is also sometimes referred to as cip.
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Andosols are a Reference Soil Group of the World Reference Base for Soil Resources (WRB). They are closely related to other types of soils such as Vitrosols, Vitrandosols, Vitrons and Pumice Soils that are used in different soil classification systems. Poorly developed Andosols are often rich in vitreous materials and are therefore also called Vitric Andosols. Andosols are usually defined as soils containing high proportions of glass and amorphous colloidal materials, including allophane, imogolite and ferrihydrite.
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Typical dots are made of binary compounds such as lead sulfide, lead selenide, cadmium selenide, cadmium sulfide, cadmium telluride, indium arsenide, and indium phosphide. Dots may also be made from ternary compounds such as cadmium selenide sulfide. Further, recent advances have been made which allow for synthesis of colloidal perovskite quantum dots. These quantum dots can contain as few as 100 to 100,000 atoms within the quantum dot volume, with a diameter of ≈10 to 50 atoms.
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Aromatic self- assembled monolayers (SAMs) (e.g. 4-nitrobenzoic acid) can be used to improve the band alignment at electrodes for better efficiencies. This technique has provided a record power conversion efficiency (PCE) of 10.7%. The SAM is positioned between ZnO-PbS colloidal quantum dot (CQD) film junction to modify band alignment via the dipole moment of the constituent SAM molecule, and the band tuning may be modified via the density, dipole and the orientation of the SAM molecule.
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Differential centrifugation Differential centrifugation (also known as differential velocity centrifugation) is a common procedure in biochemistry and cell biology, which is used to separate organelles and other sub-cellular particles based on their sedimentation rate. Although often applied in biological analysis, differential centrifugation is a general technique also suitable for crude purification of non-living suspended particles (e.g. nanoparticles, colloidal particles, viruses). In a typical case where differential centrifugation is used to analyze cell-biological phenomena (e.g.
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Specific feeding strategies and mechanisms are employed to match specific niches. Herbivorous and detritivorous species fragment biological material present in soil and leaf litter, supporting decomposition and increasing the availability of nutrients for various species of microbes and fungi. Carnivorous species maintain populations of small invertebrates such as nematodes, rotifers, and other collembolan species. Springtails commonly consume fungal hyphae and spores, but also have been found to consume plant material and pollen, animal remains, colloidal materials, minerals and bacteria.
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AAPS J. 16, 11–14 (2014). Hence and due to their complexity and specific composition mix, such colloidal iron carbohydrate drugs cannot be fully identified, characterized, quantitated and/or described by physiochemical means to define their pharmaceutical properties. Therefore, contradictory to the generic paradigm pathway, relying on a full pharmaceutical identity and sameness in vitro evaluation exercise, they need additional (biological, in vivo) evaluation with a reference product to assess comparability e.g. in tissue targeting in the body.
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The depth, texture and composition of soils can influence its water retaining and draining ability. Soils containing large amounts of organic material tend to have the highest water retention abilities. These types of soils include deep loams, silty soils like what is typically found on the fertile valley floors such as in the California's Napa Valley. Clay particles have the potential to remain in colloidal suspension for long periods of time when it is dissolved in water.
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The particles are very small, ranging from 1-2 μm down to 0.1 μm or less. Some metals like nickel and copper give black colloidal suspensions that do not settle, even with centrifugation, and cannot be filtered. Other metals such as magnesium and cobalt give larger particles, but these are found to be composed mainly of the alkali salt by-product, with the metal dispersed in them as much finer particles or even as an amorphous phase.
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Onium salts, which have been used in the cathodic process, are not protonated bases and do not deposit by the mechanism of charge destruction. These type of materials can be deposited on the cathode by concentration coagulation and salting out. As the colloidal particles reach the solid object to be coated, they become squeezed together, and the water in the interstices is forced out. As the individual micelles are squeezed, they collapse to form increasingly larger micelles.
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Colloidal stability is inversely proportional to the size of the micelle, so as the micelles get bigger, they become less and less stable until they precipitate from solution onto the object to be coated. As more and more charged groups are concentrated into a smaller volume, this increases the ionic strength of the medium, which also assists in precipitating the materials out of solution. Both of these processes are occurring simultaneously and both contribute to the deposition of material.
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Particles in ferrofluids are dispersed in a liquid, often using a surfactant, and thus ferrofluids are colloidal suspensions – materials with properties of more than one state of matter. In this case, the two states of matter are the solid metal and liquid it is in. This ability to change phases with the application of a magnetic field allows them to be used as seals, lubricants, and may open up further applications in future nanoelectromechanical systems. True ferrofluids are stable.
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Ice cream sandwich Ice cream is considered a colloidal system. It is composed by ice cream crystals and aggregates, air that does not mix with the ice cream by forming small bubbles in the bulk and partially coalesced fat globules. This dispersed phase made from all the small particles is surrounded by an unfrozen continuous phase composed by sugars, proteins, salts, polysaccharides and water. Their interactions determine the properties of ice cream, whether soft and whippy or hard.
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Together with Staudinger's Nobel Prize in 1953Nobel Prize in Chemistry 1953. this new approach led to a reduced interest in biopolymers as colloids in biology, apart from their propensity to form solid crystals for structure determination by X-ray crystallography. Nevertheless, the fields of colloid chemistry and polymer physics continued unabated to characterise the non-stoichiometric interactions occurring during colloidal, liquid crystal and other phase behaviour of macromolecular polymers, particularly synthetic polymers developed for industrial applications.
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Surface plasmon resonance (SPR) band of colloidal gold nanoparticles (AuNPs) is one electromagnetic property that was examined. In AuNPs, the free electrons within the metal surface will interact with light, which results in large oscillations in the surface electromagnetic field. This results in the particles absorbing light strongly at the particular resonant frequencies of these electrons, promoting SPR bands. In order to use this concept in sensor systems, one must use them in surface enhances Raman spectroscopy (SERS).
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It is less commonly used as a root-end filling material, as its placement is technique sensitive, particularly to moisture. Moisture contamination will result in a weakened bond that is very susceptible to leakage and subsequent failure. There is some evidence that, when placed correctly, composite resin can produce high success rates. Mineral trioxide aggregate (MTA) is a cement containing mineral oxides which absorb water to form a colloidal gel, which solidifies over a period of approximately 4 hours.
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The purity of the water used in the preparation of the formazine dispersion is also important as it cannot initially contain colloidal particles. Experience shows that water filtered as required has a residual scatter of about 0.02 FTU = 20 mFTU (inherent brightening effect). This has to be taken into account during calibration and for the detection of very low turbidity levels. The commercially available aqueous dispersions of formazine standard are often traceable according to the EN ISO 7027 norm.
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Hydrogel of a superabsorbent polymer A hydrogel is a network of crosslinked polymer chains that are hydrophilic, sometimes found as a colloidal gel in which water is the dispersion medium. A three-dimensional solid results from the hydrophilic polymer chains being held together by cross-links. The crosslinks which bond the polymers of a hydrogel fall under two general categories: physical and chemical. Physical crosslinks consist of hydrogen bonds, hydrophobic interactions, and chain entanglements (among others).
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Semiconducting GeTe nanowires (NW) and nanohelices (NH) are synthesized via vapor transport method, with metal nanoparticle catalysts. GeTe was evaporated and carried by Ar gas at optimum temperature, pressure, time, and gas flow rate to the downstream collecting/grow site (SiO2 surface coated with colloidal gold nanoparticles). High temperature over 500 °C produces thicker nanowires and crystalline chunks. Au is essential to the growth of NW and NH and is suggested to the metal catalyst of the reaction.
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While silver is potentially toxic to humans at high doses, the risk of serious harm from low doses, given over a short term, is small. Silver is used in some medical appliances because of its anti-microbial nature, which stems from the oligodynamic effect. Chronic ingestion or inhalation of silver preparations (especially colloidal silver) can lead to argyria in the skin and other organs. This is not life- threatening, but is considered by most to be cosmetically undesirable.
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Due to their optical, electronic, and molecular-recognition properties, gold nanoparticles are the subject of substantial research, with many potential or promised applications in a wide variety of areas, including electron microscopy, electronics, nanotechnology, materials science, and biomedicine. The properties of colloidal gold nanoparticles, and thus their potential applications, depend strongly upon their size and shape. For example, rodlike particles have both transverse and longitudinal absorption peak, and anisotropy of the shape affects their self-assembly.
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Tyndall scattering, i.e. colloidal particle scattering, is much more intense than Rayleigh scattering due to the bigger particle sizes involved. The importance of the particle size factor for intensity can be seen in the large exponent it has in the mathematical statement of the intensity of Rayleigh scattering. If the colloid particles are spheroid, Tyndall scattering can be mathematically analyzed in terms of Mie theory, which admits particle sizes in the rough vicinity of the wavelength of light.
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More recently microlens arrays have been fabricated using convective assembly of colloidal particles from suspension. Advances in technology have enabled micro-lenses to be designed and fabricated to close tolerances by a variety of methods. In most cases multiple copies are required and these can be formed by moulding or embossing from a master lens array. The master lens array may also be replicated through the generation of an electroform using the master lens array as a mandrel.
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It would therefore appear desirable to process a material in such a way that it is physically uniform with regard to the distribution of components and porosity, rather than using particle size distributions which will maximize the green density. The containment of a uniformly dispersed assembly of strongly interacting particles in suspension requires total control over particle- particle interactions. Monodisperse colloids provide this potential.Allman III, R. M. in Microstructural Control Through Colloidal Consolidation, Aksay, I. A., Adv. Ceram.
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The canal water took on a reddish-purple color, and a colloidal mixture described as "black mayonnaise" accumulated on its bottom. In 1887, the New York State Legislature closed the Bond Street outflow point. By 1889, pollution in the Gowanus Canal had become so bad that the Legislature appointed a commission to study ways to ameliorate the canal's condition. It concluded that the canal would be best off if it were closed to commercial traffic and then covered-over.
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Shows various thermal profiles and their effect on subsequent microstructure of freeze-casts. The structure in this final region contains long, aligned lamellae that alternate between ice crystals and ceramic walls. The faster a sample is frozen, the finer its solvent crystals (and its eventual macroporosity) will be. Within the SSZ, the normal speeds which are usable for colloidal templating are 10 – 100 mm s−1 leading to solvent crystals typically between 2 mm and 200 mm.
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A version of the concentric cylinder packed particles or close-packed polymer to create a three-dimensionally ordered macroporous (3DOM) carbon anode. This system is fabricated by using colloidal crystal templating, electrochemical thin-film growth, and soft sol–gel chemistry. 3DOM materials have a unique structure of nanometer thick walls that surround interconnected and closed-packed sub-micrometer voids. The 3DOM structure is coated with a thin polymer layer and then filled with second conducting phase.
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The term dichroic is used more precisely when labelling interference filters for laboratory use. Another dichroic glass material first appeared in a few pieces of Roman glass from the 4th century and consists of a translucent glass containing colloidal gold and silver particles dispersed in the glass matrix in certain proportions so that the glass has the property of displaying a particular transmitted color and a completely different reflected color, as certain wavelengths of light either pass through or are reflected. In ancient dichroic glass, as seen in the most famous piece, the 4th-century Lycurgus cup in the British Museum, the glass has a green color when lit from in front in reflected light, and another, purple-ish red, when lit from inside or behind the cup so that the light passes through the glass. This is not due to alternating thin metal films but colloidal silver and gold particles dispersed throughout the glass, in an effect similar to that seen in gold ruby glass, though that has only one color whatever the lighting.
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The focus of his research is on developing methods for controlling the architecture of molecules and materials on the 1 – 100 nm length scale and utilizing such structures in the development of analytical tools that can be used in the areas of chemical and biological sensing, lithography, catalysis, and optics. Mirkin has pioneered the use of DNA and nanoparticles as synthons in materials science and the development of nanoparticle-based biodiagnostics. A common strategy used by Mirkin's group is the use of the unique properties of spherical nucleic acids (SNAs), spherical arrangements of nucleic acids with or without organic or inorganic nanoparticle cores, to enable the synthesis of novel materials and colloidal crystals, the development of high sensitivity probes for chemical and medical diagnostic purposes, and single-entity structures capable of intracellular gene regulation. His 1996 work with SNA-gold nanoparticle conjugates introduced the concept of a nanoparticle as an atom and nucleic acids as bonds, and it laid the ground work for the fields of colloidal crystal engineering with DNA and molecular diagnostics based upon well-defined nanoparticle and nanocrystal bioconjugates.
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This method of cell sorting uses the behavior of the fluid itself within the microchannels to alter and separate cells based on size and morphology. The fluid in a colloidal solution will be subject to a velocity profile due to the interactions of the fluid with the walls of the channel while the cells in the solution are subject to various drag and inertial forces that are dependent on the size of the cell and balance accordingly at different locations along the velocity profile. In curved microfluidic channels, vortices are formed due to the Dean force which locate different sized particles in different cross sectional locations due to the Reynolds number and curve radius of curvature. For example, in a straight channel, larger cells in colloidal solution are found closer to the center of the microchannel than smaller cells due to the larger drag forces from the wall that pushes the cell away from the wall and the shear gradient force from the velocity profile that balances this wall drag force to set the cell into equilibrium.
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Louis E. Brus is the S. L. Mitchell Professor of Chemistry at Columbia University. He is the discoverer of the colloidal semi-conductor nanocrystals known as quantum dots. Brus received the Franklin Institute's 2012 Bower Award and Prize for Achievement in Science, and was chosen for the 2010 NAS Award in Chemical Sciences. He received the inaugural Kavli Prize for nanoscience in 2008, and was co-recipient of the 2006 R. W. Wood prize of the Optical Society of America.
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Patchy particles are micron- or nanoscale colloidal particles that are anisotropically patterned, either by modification of the particle surface chemistry ("enthalpic patches"), through particle shape ("entropic patches"), or both. The particles have a repulsive core and highly interactive surfaces that allow for this assembly. The placement of these patches on the surface of a particle promotes bonding with patches on other particles. Patchy particles are used as a shorthand for modelling anisotropic colloids, proteins and water and for designing approaches to nanoparticle synthesis.
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There are instances in which silver nanoparticles and colloidal silver are used in consumer goods. Samsung for example claimed that the use of silver nanoparticles in washing machines would help to sterilize clothes and water during the washing and rinsing functions, and allow clothes to be cleaned without the need for hot water. The nanoparticles in these appliances are synthesized using electrolysis. Through electrolysis, silver is extracted from metal plates and then turned into silver nanoparticles by a reduction agent.
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The polyol process is a particularly useful method because it yields a high degree of control over both the size and geometry of the resulting nanoparticles. In general, the polyol synthesis begins with the heating of a polyol compound such as ethylene glycol, 1,5-pentanediol, or 1,2-propylene glycol7. An Ag+ species and a capping agent are added (although the polyol itself is also often the capping agent). The Ag+ species is then reduced by the polyol to colloidal nanoparticles.
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In 1938 he won a scholarship to Caius College, Cambridge to read chemistry. He graduated in 1941 with an upper second class degree, and became a research student in the Department of Colloidal Science at Cambridge. During the Second World War Robertson served in the Operational Research Section of Coastal Command. The head of the unit was Conrad Hal Waddington, who after the war invited Robertson to join him in a new research body, the National Animal Breeding and Genetics Research Organisation (NABGRO).
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The magnetic nanoparticles are made of iron oxide, which is fully biodegradable, coated with specific cationic proprietary molecules varying upon the applications. Their association with the gene vectors (DNA, siRNA, ODN, virus, etc.) is achieved by salt-induced colloidal aggregation and electrostatic interaction. The magnetic particles are then concentrated on the target cells by the influence of an external magnetic field generated by magnets. The cellular uptake of the genetic material is accomplished by endocytosis and pinocytosis, two natural biological processes.
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The concrete walls of the chamber are over a metre thick to give it sufficient weight to prevent it floating during a flood. A control room above the chamber houses the switch board, instruments and a diesel stand-by generator. Water is drawn from the river and passes through rotary screens having a fine wire mesh of 200 openings to the inch (80 per cm). This removes all solid matter except colloidal clay, which when present gives rise to a milky appearance.
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Quasi-crystals are supramolecular aggregates exhibiting both crystalline (solid) properties as well as amorphous, liquid-like properties. Self- organized structures termed "quasi-crystals" were originally described in 1978 by the Israeli scientist Valeri A. Krongauz of the Weizmann Institute of Science, in the Nature paper, Quasi-crystals from irradiated photochromic dyes in an applied electric field. Scheme 1. Formation of merocyanine dipoles upon irradiation In his 1978 paper Krongauz coined the term “Quasi-Crystals” for the new self-organized colloidal particles .
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The damage to the water infrastructure was described as being of "unexpected magnitude," with 160,000 left without water a week after the storm made landfall. The standing water left following the rainfall caused concern of outbreaks of various diseases, including cholera. Consequently, the population was warned to boil or otherwise disinfect water to prevent disease. In areas where the storm's impact made it difficult to boil water due to the unavailability of gas or stoves, 70,000 jars with colloidal silver were distributed.
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On March 12, 2020, Attorney General of New York Letitia James issued a cease and desist letter to Jones concerning InfoWarss sale of unapproved products that the website falsely asserted to be government-approved treatments for coronavirus disease 2019 (COVID-19). On April 9, the FDA ordered InfoWars to discontinue the sale of a number of products marketed as remedies for COVID-19 in violation of the Federal Food, Drug, and Cosmetic Act, including toothpaste, liquids, and gels containing colloidal silver.
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Experiments performed in microgravity on the Space Shuttle Columbia suggest that the typical face-centered cubic structure may be induced by gravitational stresses. Crystals tend to exhibit the hcp structure alone (random stacking of hexagonally close-packed crystal planes), in contrast with a mixture of (rhcp) and face-centred cubic packing when allowed sufficient time to reach mechanical equilibrium under gravitational forces on Earth. Glassy (disordered or amorphous) colloidal samples have become fully crystallized in microgravity in less than two weeks.
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Aggregation in colloidal dispersions (or stable suspensions) has been characterized by the degree of interparticle attraction. For attractions strong relative to the thermal energy (given by kT), Brownian motion produces irreversibly flocculated structures with growth rates limited by the rate of particle diffusion. This leads to a description using such parameters as the degree of branching, ramification or fractal dimensionality. A reversible growth model has been constructed by modifying the cluster-cluster aggregation model with a finite inter-particle attraction energy.
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The first representative of this class of reactions was the NaOH (outer electrolyte)+CuCl2 (inner electrolyte) . Later the NaOH+AgNO3 , the CuCl2+K3[Fe(CN)6] , the NaOH+AlCl3 , and the NH3+AgNO3 reactions in several hydrogels have also proved to show similar behavior. Precipitate patterns forming in these reactions are exceptionally rich. Besides the macroscopic shapes like layered structures, helices and cardioids, regular sheets of colloidal precipitate may also emerge with a periodicity even less than 20 micrometers (microscopic patterns).
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Another type, microscopic particles usually refers to particles of sizes ranging from atoms to molecules, such as carbon dioxide, nanoparticles, and colloidal particles. These particles are studied in chemistry, as well as atomic and molecular physics. The smallest of particles are the subatomic particles, which refer to particles smaller than atoms. These would include particles such as the constituents of atoms – protons, neutrons, and electrons – as well as other types of particles which can only be produced in particle accelerators or cosmic rays.
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Paʻakai Alaea, a water-soluble colloidal ocherous earth, was used for coloring salt, which in turn was traditionally used by Hawaiians to cleanse, purify and bless tools, canoes, homes and temples. Alaea salt is also used in several native Hawaiian dishes kalua pig, poke, and pipikaula (Hawaiian jerky). In the 19th century Hawaiians began producing large amounts of alaea salt using European salt making techniques and became a leading supplier to fishermen in the Pacific Northwest for curing salmon.Kurlansky, Mark. pg. 405.
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The strength of these forces increases with the magnitude of the surface charge density (or the electrical surface potential). For two similarly charged objects, this force is repulsive and decays exponentially at larger distances, see figure. For unequally charged objects and eventually at shorted distances, these forces may also be attractive. The theory due to Derjaguin, Landau, Verwey, and Overbeek (DLVO) combines such double layer forces together with Van der Waals forces in order to estimate the actual interaction potential between colloidal particles.
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Peter Petrovich von Weymarn (commonly mis-spelt von Weimarn) (July 17, 1879 - June 2, 1935) was a Russian chemist born in St. Petersburg known for his groundwork in colloid science. In 1906 he stated the von Weymarn law: Colloidal dispersions are obtained from very dilute or very concentrated solutions but not from intermediate solutions. The relative supersaturation ratio herein is defined by S=(Q-L)/L (where Q is the amount of the dissolved material and L is its solubility).
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Vold moved to southern California in 1941. She worked as a chemist for Union Oil Company during World War II. In 1947 she became a Research Associate at the University of Southern California, and from 1958 until 1974 she held adjunct professor status there. Her research continued to the end of her life, when she was working from a hospital bed on her final paper on premicelles. In 1964, Vold and her husband were authors of Colloidal Chemistry, a widely used reference text.
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She took part in the Royal Society parliamentary pairing scheme in 2007, and was paired with Andrew Miller, then Chair of the Science and Technology Select Committee. In 2009 Thanh joined University College London as an Associate Professor of Nanotechnology, where she is based in the Davy Faraday Laboratory. She studies nanomaterials and their applications in biomedicine, and has continued to investigate colloidal gold. She is particularly interested in magnetic nanoparticles and how they can be used to treat cancer.
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Nevertheless, the average properties of lab produced humic substances from different sources are remarkably similar. Humic substances in soils and sediments can be divided into three main fractions: humic acids, fulvic acids, and humin. Their presence and relative abundance is inferred by lab extraction, a process which alters their original form beyond recognition. The humic and fulvic acids are extracted as a colloidal sol from soil and other solid phase sources into a strongly basic aqueous solution of sodium hydroxide or potassium hydroxide.
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DLVO theory describes the interaction potential between charged surfaces. It is the sum of electrostatic double layer, which can be either attractive of repulsive, and attractive Van der Waals interactions of the charge surfaces. DLVO theory is applied widely in explaining the aggregation and deposition of colloidal and nano particles such as Fullerene C60 in aquatic system. Because bacteria and colloid particles both share the similarities in size and surface charge, the deposition of bacteria also can be describe by the DLVO theory.
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Formation and examples of membraneless organelles Biomolecular condensates are a class of non-membrane bound organelles and organelle subdomains. As with other organelles, biomolecular condensates are specialized subunits of the cell. However, unlike many organelles, biomolecular condensate composition is not controlled by a bounding membrane. Instead they can form through a range of different processes, the most well-known of which is phase separation of proteins, RNA and other biopolymers into either colloidal emulsions, liquid crystals, solid crystals or aggregates within cells.
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One of the primary methods of optical air sensing involves taking a sol-gel, which is made by taking a sol, a liquid with stable colloidal particles, and mixing it with a gel, which is a three dimensional continuous network encompassing a liquid. The sol-gel is then exposed to a certain indicator which becomes part of the sol-gel. Typically the production of a sol-gel follows a hydrolysis and then condensation pathway. Hydrolysis involves adding a hydrogen atom onto the gel.
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Congo red is an organic compound, the sodium salt of 3,3′-([1,1′-biphenyl]-4,4′-diyl)bis(4-aminonaphthalene-1-sulfonic acid). It is an azo dye. Congo red is water-soluble, yielding a red colloidal solution; its solubility is greater in organic solvents. However, the use of Congo red has long been abandoned, primarily because of its carcinogenic properties.Klaus Hunger, Peter Mischke, Wolfgang Rieper, Roderich Raue, Klaus Kunde, Aloys Engel: "Azo Dyes" in Ullmann’s Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim..
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This clustering behavior has been observed for self-propelled Janus particles, either platinum-coated gold particles or carbon-coated silica beads, and for magnetically or ultrasonically powered particles. Clustering has also been observed for colloidal particles composed of either an embedded hematite cube or slowly-diffusing metal ions. Clustering also occurs in enzyme molecule diffusion. In all these experiments, the motion of particles takes place on a two-dimensional surface and clustering is seen for area fractions as low as 10%.
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Microscopic analysis has failed to find any impurities such as potassium permanganate or hydrocarbons which could produce a purple-blue colour. It is now thought that the colour may be a physical phenomenon due to crystal lattice dislocation. If the regular arrangement of atoms in the fluorite molecules are disturbed or dislocated, then this may yield the blue colour in Blue John. The cause of these dislocations is unknown, but one possibility is that it is due to colloidal calcium, i.e.
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However, more recently the small chromophore solvatochromism hypothesis has been challenged for carbon nanotubes in light of older and newer data showing electrochromic behavior. These and other observations regarding non-linear processes on the semiconducting nanotube suggest colloidal models will require new interpretations that are in line with classic semiconductor optical processes, including electrochemical processes, rather than small molecule physical descriptions. Conflicting hypotheses may be due to the fact the nanotube is only a single atom thick material interface unlike other "bulk" nanomaterials.
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In industry, cavitation is often used to homogenize, or mix and break down, suspended particles in a colloidal liquid compound such as paint mixtures or milk. Many industrial mixing machines are based upon this design principle. It is usually achieved through impeller design or by forcing the mixture through an annular opening that has a narrow entrance orifice with a much larger exit orifice. In the latter case, the drastic decrease in pressure as the liquid accelerates into a larger volume induces cavitation.
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These stabilizer molecules are generally graft or block copolymers, and can be preformed or can form in situ during the reaction. Typically, one side of the stabilizer copolymer has an affinity for the solvent while the other side has an affinity for the polymer particle being formed. These molecules play a crucial role in dispersion polymerization by forming a “hairy layer” around the particles that prevents particle coagulation. This controls size and colloidal stability of the particles in the reaction system.
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Diffusing-wave spectroscopy (DWS) is an optical technique derived from dynamic light scattering (DLS) that studies the dynamics of scattered light in the limit of strong multiple scattering. It has been widely used in the past to study colloidal suspensions, emulsions, foams, gels, biological media and other forms of soft matter. If carefully calibrated, DWS allows the quantitative measurement of microscopic motion in a soft material, from which the rheological properties of the complex medium can be extracted via the microrheology approach.
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The chloride ligands on [PtCl4]2− are displaced by many other ligands. Upon reaction with triphenylphosphine, [PtCl4]2− converts to cis- bis(triphenylphosphine)platinum chloride: :PtCl42− \+ 2 PPh3 → cis- PtCl2(PPh3)2 \+ 2 Cl− The anti-cancer drug Cisplatin can similarly be prepared: :PtCl42− \+ 2 NH3 → cis-PtCl2(NH3)2 \+ 2 Cl− Enedithiolates displace all four chloride ligands to give bis(dithiolene) complexes. Reduction gives colloidal platinum of potential interest for catalysis. Historically, an important reaction involves ammonia and [PtCl4]2−.
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Prepared shrimp paste with chilli, Thai lime leaves, sugar and water added. Duxelles being cooked, which is eventually reduced into a paste A food paste is a semi-liquid colloidal suspension, emulsion, or aggregation used in food preparation or eaten directly as a spread. Pastes are often highly spicy or aromatic, are often prepared well in advance of actual usage, and are often made into a preserve for future use. Common pastes are some fruit preserves, curry pastes, and nut pastes.
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She received many awards for her research contributions including induction into the Latvian Socialist Soviet Republic Academy of Sciences, the Medal For Valiant Labor in the Great Patriotic War, Order of the Red Banner of Labor, Hero of Socialist Labor, the Order of Lenin and the "Hammer and Sickle" gold medal. Liepiņa's research interests were diverse, encompassing several different areas of physical chemistry and colloidal chemistry. She investigated colloids' effects on corrosion, absorption in solids, dispersion, formation of hydrides, and surface reactions.
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283x283px Gold nanoparticles in chemotherapy and radiotherapy is the use of colloidal gold in therapeutic treatments, often for cancer or arthritis. Gold nanoparticle technology shows promise in the advancement of cancer treatments. Some of the properties that gold nanoparticles possess, such as small size, non-toxicity and non-immunogenicity make these molecules useful candidates for targeted drug delivery systems. With tumor-targeting delivery vectors becoming smaller, the ability to by-pass the natural barriers and obstacles of the body becomes more probable.
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These usually contain colloidal oatmeal, hydrocortisone, Aloe vera, pramoxine hydrochloride, menthol, diphenhydramine, sulfur or salicylic acid. These ingredients are aimed to reduce the inflammation, cure the condition and ease the symptoms at the same time while providing comfort to the pet. Antiseborrheic shampoos are those especially designed for pets with scales or those with excessive oily coats. These shampoos are made of sulfur, salicylic acid, refined tar (which cannot be used on cats), selenium sulfide (cannot be used on cats) and benzoyl peroxide.
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He considered sleep as a process of self-poisoning by some toxin, which shortens the lifetime. Between 1918 and 1920, Ostromislensky headed a chemical therapeutic laboratory of the Chemical-Pharmaceutical Institute in Moscow. There he studied the structure and properties of the popular foreign drug Salvarsan and developed the method of manufacturing a domestic analogue called Arsol. Arsol was based on relatively cheap production of colloidal arsenic that was important in the time of the Civil Wars and economic crisis in Russia.
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Unless they form a stable sediment in the final container, the spent finings are usually discarded from the beverage along with the target compounds that they capture. Substances used as finings include egg whites, blood, milk, isinglass, and Irish moss. These are still used by some producers, but more modern substances have also been introduced and are more widely used, including bentonite, gelatin, casein, carrageenan, alginate, diatomaceous earth, pectinase, pectolyase, PVPP, kieselsol (colloidal silica), copper sulfate, dried albumen (egg whites), hydrated yeast, and activated carbon.
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Sandwich assays are generally used for larger analytes because they tend to have multiple binding sites. As the sample migrates through the assay it first encounters a conjugate, which is an antibody specific to the target analyte labelled with a visual tag, usually colloidal gold. The antibodies bind to the target analyte within the sample and migrate together until they reach the test line. The test line also contains immobilized antibodies specific to the target analyte, which bind to the migrated analyte bound conjugate molecules.
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Particle agglomerates defined as "hard agglomerates" are more difficult to redisperse to the initial single particles. In the course of agglomeration, the agglomerates will grow in size, and as a consequence they may settle to the bottom of the container, which is referred to as sedimentation. Alternatively, a colloidal gel may form in concentrated suspensions which changes its rheological properties. The reverse process whereby particle agglomerates are re-dispersed as individual particles, referred to as peptization, hardly occurs spontaneously, but may occur under stirring or shear.
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This method avoids the drying, cleaning, and re-dispersion processes, which are generally required with alternative colloidal synthesis methods. Importantly, the electrolysis strategy also decreases the production cost of Ag nanoparticles, making these washing machines more affordable to manufacture. Samsung has described the system: > [A] grapefruit-sized device alongside the [washer] tub uses electrical > currents to nanoshave two silver plates the size of large chewing gum > sticks. Resulting in positively charged silver atoms-silver ions (Ag+)-are > injected into the tub during the wash cycle.
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Alternatively, material extracted from the teeth of people during dental procedures can be used to quantify their cumulative exposure to ionizing radiation. People exposed to radiation from the Chernobyl disaster have been examined by this method. Radiation-sterilized foods have been examined with EPR spectroscopy, the aim being to develop methods to determine whether a particular food sample has been irradiated and to what dose. EPR can be used to measure microviscosity and micropolarity within drug delivery systems as well as the characterization of colloidal drug carriers.
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Semiconductors with the highest thermal conductivity are boron arsenide (1300 W/(m·K)) and boron phosphide (500 W/(m·K)). The heat sink's contact surface (the base) must be flat and smooth to ensure the best thermal contact with the object needing cooling. Frequently a thermally conductive grease is used to ensure optimal thermal contact; such compounds often contain colloidal silver. Further, a clamping mechanism, screws, or thermal adhesive hold the heat sink tightly onto the component, but specifically without pressure that would crush the component.
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A photograph and representative spectrum of photoluminescence from colloidal CdSe quantum dots Cadmium electroplating, consuming 6% of the global production, is used in the aircraft industry to reduce corrosion of steel components. This coating is passivated by chromate salts. A limitation of cadmium plating is hydrogen embrittlement of high- strength steels from the electroplating process. Therefore, steel parts heat- treated to tensile strength above 1300 MPa (200 ksi) should be coated by an alternative method (such as special low-embrittlement cadmium electroplating processes or physical vapor deposition).
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Colloidal crystals are receiving increased attention, largely due to their mechanisms of ordering and self-assembly, cooperative motion, structures similar to those observed in condensed matter by both liquids and solids, and structural phase transitions. Phase equilibrium has been considered within the context of their physical similarities, with appropriate scaling, to elastic solids. Observations of the interparticle separation distance has shown a decrease on ordering. This led to a re-evaluation of Langmuir's beliefs about the existence of a long-range attractive component in the interparticle potential.
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Long-range order has been observed in thin films of colloidal liquids under oil—with the faceted edge of an emerging single crystal in alignment with the diffuse streaking pattern in the liquid phase. Structural defects have been directly observed in the ordered solid phase as well as at the interface of the solid and liquid phases. Mobile lattice defects have been observed via Bragg reflections, due to the modulation of the light waves in the strain field of the defect and its stored elastic strain energy.
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Using a single body-centered cubic colloidal crystal, the occurrence of Kossel lines in diffraction patterns were used to monitor the initial nucleation and subsequent motion caused distortion of the crystal. Continuous or homogeneous deformations occurring beyond the elastic limit produce a 'flowing crystal', where the nucleation site density increases significantly with increasing particle concentration. Lattice dynamics have been investigated for longitudinal as well as transverse modes. The same technique was used to evaluate the crystallization process near the edge of a glass tube.
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Surface and colloidal properties of chalks: A novel approach using surfactants to convert normal chalks into dustless chalks. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 480, pp.236-244. Colored chalks, pastel chalks, and sidewalk chalk (shaped into larger sticks and often colored), used to draw on sidewalks, streets, and driveways, are primarily made of gypsum. Open chalk pit, Seale, Surrey, UK Child drawing with sidewalk chalk Chalk is a source of quicklime by thermal decomposition, or slaked lime following quenching of quicklime with water.
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Typical RAS solids removal involves a sand filter or particle filter where solids become lodged and can be periodically backflushed out of the filter. Another common method is the use of a mechanical drum filter where water is run over a rotating drum screen that is periodically cleaned by pressurized spray nozzles, and the resulting slurry is treated or sent down the drain. In order to remove extremely fine particles or colloidal solids a protein fractionator may be used with or without the addition of ozone (O3).
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Ti3C2 MXene produced by HF etching has accordion-like morphology with residual forces that keep MXene layers together preventing separation into individual layers. Although those forces are quite weak, ultrasound treatment results only in very low yields of single-layer flakes. For large scale delamination, DMSO is intercalated into ML-MXene powders under constant stirring to further weaken the interlayer bonding and then delaminated with ultrasound treatment. This results in large scale layer separation and formation of the colloidal solutions of the FL-MXene.
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The Department of Interfaces, headed by Helmuth Möhwald, is primarily motivated to understand molecular interfaces and to relate this to colloidal systems which are by nature determined by the large surface/volume ratio. Consequently, the strength of the department in characterizing planar or quasi-planar interfaces has been increased and in addition it has been tried successfully to transfer this knowledge to curved interfaces. From this we have again learned about planar interfaces since surfaces could be studied by techniques requiring large surface area (NMR, DSC).
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Dilution of sewage directly increases costs of pumping and chlorination, ozonation, or ultraviolet disinfection. Physical treatment structures including screens and pumps must be enlarged to handle the peak flow. Primary clarifiers must also be enlarged to treat average flows, although primary treatment of peak flows may be accomplished in detention basins. Biological secondary treatment is effective only while the concentration of soluble and colloidal pollutants (typically measured as biochemical oxygen demand or BOD) remains high enough to sustain a population of microorganisms digesting those pollutants.
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Hendrik Casimir (1958) In 1948 Hendrik Casimir showed that one consequence of the zero-point field is an attractive force between two uncharged, perfectly conducting parallel plates, the so-called Casimir effect. At the time, Casimir was studying the properties of "colloidal solutions". These are viscous materials, such as paint and mayonnaise, that contain micron-sized particles in a liquid matrix. The properties of such solutions are determined by van der Waals forces – short-range, attractive forces that exist between neutral atoms and molecules.
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The new instruments were able to endure pressures of up to , as opposed to conventional machines, which, as previously state, can hold up to . UPLC is an alternative solution to the same problems monolithic columns solve. Similarly to UPLC, monolith chromatography can help the bottom line by increasing sample throughput, but without the need to spend capital on new equipment. In 1996, Nobuo Tanaka, at the Kyoto Institute of Technology, prepared silica monoliths using a colloidal suspension synthesis (aka “sol- gel”) developed by a colleague.
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One focus of Ginger's career has been the development of more efficient and effective methods of solar energy capture. Ginger's group has developed of thin film semiconductors that are sturdier and less expensive to manufacture than traditional silicon solar panels. The development of these semi conductors that can be cast onto flexible surfaces has opened a wide range of possibilities of future applications. The group conducts research on a variety of different types of solar cell components including perovskites, organic semiconductors, and colloidal quantum dots.
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A familiar example of the opposite, a shear thinning fluid, or pseudoplastic fluid, is wall paint: The paint should flow readily off the brush when it is being applied to a surface but not drip excessively. Note that all thixotropic fluids are extremely shear thinning, but they are significantly time dependent, whereas the colloidal "shear thinning" fluids respond instantaneously to changes in shear rate. Thus, to avoid confusion, the latter classification is more clearly termed pseudoplastic. Another example of a shear thinning fluid is blood.
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Elmer Kraemer's scientific career was prematurely cut short by his unexpected and quick death from a cerebral hemorrhage, on Sept. 7, 1943, at St. Joseph's Hospital in Pittsburgh, Pennsylvania, while he was attending a luncheon at the 106th meeting of the American Chemical Society. A short newspaper article called Dr. Kraemer an "internationally known colloidal chemist" who "was internationally recognized as an outstanding investigator in the field of colloid chemistry." Kraemer was survived by his wife Huldah Florence Kraemer and his two sons Herbert and Paul Kraemer.
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Sodha has done extensive research in the physical science disciplines of plasma and energy. He is credited with pioneering researches on colloidal plasmas, optics and Akhamanov's formulation and he presented papers on quantitative theory of image formation in layered media. His book, Microwave Propagation in Ferrimagnetics is reported to be the first book on the subject. He has also published 13 books including Solar Crop Drying, Solar Distillation and Solar Passive Building: Science and Design and had edited a book, Sodha Reviews of Renewable Energy Resources.
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Formazine (formazin) is a heterocyclic polymer produced by reaction of hexamethylenetetramine with hydrazine sulfate. Turbidity standards of 5, 50, and 500 NTU The hexamethylenetetramine tetrahedral cage-like structure, similar to adamantane, serves as molecular building block to form a tridimensional polymeric network. Formazine is very poorly soluble in water and when directly synthesized in aqueous solution, by simply mixing its two highly soluble precursors, it forms small size colloidal particles. These organic colloids are responsible of the light scattering of the formazine suspensions in all the directions.
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On March 12, 2020, Jones was issued a cease and desist from the Attorney General of New York, after he claimed, in complete absence of evidence, that products he sold, including colloidal silver toothpaste and dietary supplements, were an effective treatment for COVID-19. The Food and Drug Administration also sent him a letter on April 9, 2020 warning that the federal government might proceed to seize the products he was marketing for COVID-19 or fine him if he continued to sell them.
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Apart from Zsigmondy, Theodor Svedberg, who invented ultracentrifugation, and Gustav Mie, who provided the theory for scattering and absorption by spherical particles, were also interested in the synthesis and properties of colloidal gold. With advances in various analytical technologies in the 20th century, studies on gold nanoparticles has accelerated. Advanced microscopy methods, such as atomic force microscopy and electron microscopy, have contributed the most to nanoparticle research. Due to their comparably easy synthesis and high stability, various gold particles have been studied for their practical uses.
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They observed that the micron-sized colloids generated a resistant film at the interface between the two immiscible phases, inhibiting the coalescence of the emulsion drops. These Pickering emulsions are formed from the self-assembly of colloidal particles in two-part liquid systems, such as oil-water systems. The desorption energy, which is directly related to the stability of emulsions depends on the particle size, particles interacting with each other, and particles interacting with oil and water molecules. Self-assembly of solid nanoparticles at oil-water interface.
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A system, where structure formation can be visualized directly is given by a colloidal mono-layer which forms a hexagonal crystal in two dimensions. The phase transition is described by the so called Kosterlitz–Thouless–Halperin–Nelson–Young theory where translational and orientational symmetry are broken by two Kosterlitz–Thouless transitions. The corresponding topological defects are dislocations and disclinations in two dimensions. The latter are nothing else but the monopoles of the high-symmetry phase within the six-fold director field of crystal axes.
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Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution. Interface and colloid science is an interdisciplinary intersection of branches of chemistry, physics, nanoscience and other fields dealing with colloids, heterogeneous systems consisting of a mechanical mixture of particles between 1 nm and 1000 nm dispersed in a continuous medium. A colloidal solution is a heterogeneous mixture in which the particle size of the substance is intermediate between a true solution and a suspension, i.e. between 1–1000 nm.
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Georg Bredig (October 1, 1868, Glogau, Niederschlesien, Silesia Province – April 24, 1944, New York) was a German physical chemist. Bredig was a faculty member at the University of Leipzig (1895-1901) and professor of chemistry at Heidelberg (1901–1910); Technische Hochschule, Zurich (1910); and Technische Hochschule, Karlsruhe (1911–1933). Bredig did fundamental research in catalysis, preparing aqueous colloidal dispersions of metals and comparing the catalytic properties of metal colloids to the action of enzymes (or "ferments"). He also made significant contributions in reaction kinetics and electrochemistry.
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400px The third mechanism responsible for the translocation is based on the formation of the inverted micelles. Inverted micelles are aggregates of colloidal surfactants in which the polar groups are concentrated in the interior and the lipophilic groups extend outward into the solvent. According to this model, a penetratin dimer combines with the negatively charged phospholipids, thus generating the formation of an inverted micelle inside of the lipid bilayer. The structure of the inverted micelles permits the peptide to remain in a hydrophilic environment.
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The properties can be tuned by the thickness of the ZnS protective layers. Colloidal QD emission can be modulated from UV-Vis to the infrared by using different types of coating agents, such as ZnS, CdS, ZnSe, CdTe and PbSe. The properties of quantum dots can be also tuned by the synthetic scheme, high temperature solvent/ligand mixtures that influence the nanocrystal properties. High-quality QD contrast agents are obtained at elevated temperatures; however, because they have lower water solubility, their usage as cell markers is limited.
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This phenomenon is known as tea creaming. Research has shown that the cream is a colloidal substance that contains many of the compounds that contribute to color and flavor of black tea, and can contain up to 30% of the total solids. The driving force behind cream formation is the insolubility of theaflavin and polyphenols, which associate together through galloyl group interactions. The theaflavins have acidic properties which cause them to have a negative charge at the pH of black tea, which is roughly 4.9.
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The more noble metals (Pd, Ru, Ag, Mo, Nb, Sb, Tc) do not form fluorides in the normal salt, but instead fine colloidal metallic particles. They can plate out on metal surfaces like the heat exchanger, or preferably on high surface area filters which are easier to replace. Still, there is some uncertainty where they end up, as the MSRE only provided a relatively short operating experience and independent laboratory experiments are difficult. Gases like Xe and Kr come out easily with a sparge of helium.
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This reproduction of organisms within the filter matrix can result in the contamination of the filtrate. Depth filtration is also widely used for the clarification of cell culture clarification. The cell culture systems can contain yeast, bacterial and other contaminant cells and hence, an efficient clarification stage is vital to separate the cells and other colloidal matter to produce a particle free cell system [9]. Most depth filters used in pharmaceutical processes such as cell system harvesting are composed of cellulose fibres and filter aids.
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Köln 2003, , p. 386 Another beneficiary of their erudition was the concentration camp doctor, Waldemar Hoven who during this time obtained a doctorate with a dissertation entitled "Investigations into the treatment of pulmonary tuberculosis through the inhalation of colloidal carbon" ("Versuche zur Behandlung der Lungentuberkulose durch Inhalation von Kohlekolloid"). It subsequently transpired that the dissertation had been compiled by Wegerer and Sitte. As the end of the war approached, on 11 April 1945 Kurt Sitte was one of those freed from the Buchenwald concentration camp by members of the United States Army.
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All photographic papers consist of a light-sensitive emulsion, consisting of silver halide salts suspended in a colloidal material – usually gelatin-coated onto a paper, resin coated paper or polyester support. In black-and-white papers, the emulsion is normally sensitised to blue and green light, but is insensitive to wavelengths longer than 600 nm in order to facilitate handling under red or orange safelighting. In Chromogenic colour papers, the emulsion layers are sensitive to red, green and blue light, respectively producing cyan, magenta and yellow dye during processing.
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Hacking Matter is a 2003 book by Wil McCarthy. It deals with "programmable matter" (like colloidal films, bulk crystals, and quantum dots) that, he predicts, will someday be able mimic the properties of any natural atom, and ultimately also non-natural atoms. McCarthy predicts that programmable matter will someday change human life profoundly, and that its users will have the ability to program matter itself - to change it, from a computer, from hard to soft, from paper to stone, from fluorescent to super-reflective to invisible. In his science fiction, he calls this technology "Wellstone".
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Gabriela Basařová, 2017 Gabriela Basařová (17 January 1934 – 18 October 2019) was a Czech professor of chemistry, working in the field of fermentation chemistry, brewing, and malting. Most of her scientific and research work was devoted to the study of non-biological, so-called colloidal, turbidity of beer and methods of delaying its production during storage. She participated in scientific, educational and publishing activities in the Czech Republic and abroad, and published 538 items, mostly in foreign journals. In 2012, Basarova was awarded the State Medal of Merit.
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When one inspects a series of test tubes with suspensions prepared at different concentration of the flocculant, stable suspensions often remain dispersed, while the unstable ones settle. Automated instruments based on light scattering/transmittance to monitor suspension settling have been developed, and they can be used to probe particle aggregation. One must realize, however, that these techniques may not always reflect the actual aggregation state of a suspension correctly. For example, larger primary particles may settle even in the absence of aggregation, or aggregates that have formed a colloidal gel will remain in suspension.
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Silver nanoparticles have been synthesized on a support of inert silica spheres. The support plays virtually no role in the catalytic ability and serves as a method of preventing coalescence of the silver nanoparticles in colloidal solution. Thus, the silver nanoparticles were stabilized and it was possible to demonstrate the ability of them to serve as an electron relay for the reduction of dyes by sodium borohydride. Without the silver nanoparticle catalyst, virtually no reaction occurs between sodium borohydride and the various dyes: methylene blue, eosin, and rose bengal.
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The biological synthesis of nanoparticles has provided a means for improved techniques compared to the traditional methods that call for the use of harmful reducing agents like sodium borohydride. Many of these methods could improve their environmental footprint by replacing these relatively strong reducing agents. The problems with the chemical production of silver nanoparticles is usually involves high cost and the longevity of the particles is short lived due to aggregation. The harshness of standard chemical methods has sparked the use of using biological organisms to reduce silver ions in solution into colloidal nanoparticles.
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Anhydrous and hydrated silica surface with siloxane and silanol groups along with surface bound water molecules. The surface of solid silica in contact with water is covered by siloxane bonds (≡Si–O–Si≡) and silanol groups (≡Si–OH) sensitive to an alkaline attack by ions. The presence of these oxygen-bearing groups very prone to form hydrogen bonds with water molecules explains the affinity of silica for water and makes colloidal silica very hydrophile. Siloxane bonds may undergo hydrolysis and condensation reactions as schematically represented hereafter: Siloxane bond between two silicon atoms.
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Natural rubber is an elastomer (an elastic hydrocarbon polymer) that originally was derived from latex, a milky colloidal suspension found in specialised vessels in some plants. It is useful directly in this form (indeed, the first appearance of rubber in Europe was cloth waterproofed with unvulcanized latex from Brazil). However, in 1839, Charles Goodyear invented vulcanized rubber; a form of natural rubber heated with sulfur (and a few other chemicals), forming cross-links between polymer chains (vulcanization), improving elasticity and durability. In 1851, Nelson Goodyear added fillers to natural rubber materials to form ebonite.
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Brian O'Regan is known for his pioneering work on the deposition of meso-porous oxides from colloidal solutions that ultimately led to the first high efficiency DSSC. He has also developed the first high efficiency non-aqueous electrolyte for DSSC and more recently has overturned the belief that water is poisonous to dye sensitisation by designing water based and water tolerant DSSC. He has invented TiO2 electrodeposition from TiCl3, electrodeposition of CuSCB and non-aqueous electrodeposition of aligned mesoporous ZnO. He holds 5 patents and is the author of numerous research papers.
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He made the first measurements of polymer surface diffusion in the key limit of dilute concentration and he identified the important class of physical problems where diffusion is anomalous yet Brownian. His laboratory became interested in many instances of molecular mobility measured at the single-molecule level, including active matter and transport in living cells. The other principal current area of Granick's research concerns Janus colloidal particles, their self-assembly at rest and driven outside equilibrium. The scientific importance is to understand natural selection in the colloid world.
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Since 1962, the Environment Canada hydrologic station located on the upper portion of the Restigouche River has reported substantial increases of water flow, sometimes at over 400% above previous levels. Clear cutting of forest on both the Matapédia River and Restigouche River has created areas with no shade along the banks of the river, resulting in a faster melt than in previous years. Furthermore, the clear cut land lacks the naturally occurring moss which would help colloidal suspension in soil and retention. This creates the ideal condition for Spring thawing.
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Colloidal suspensions of nanoparticles of boric acid dissolved in petroleum or vegetable oil can form a remarkable lubricant on ceramic or metal surfaces with a coefficient of sliding friction that decreases with increasing pressure to a value ranging from 0.10 to 0.02. Self-lubricating H3BO3 films result from a spontaneous chemical reaction between water molecules and B2O3 coatings in a humid environment. In bulk-scale, an inverse relationship exists between friction coefficient and Hertzian contact pressure induced by applied load. Boric acid is used to lubricate carrom and novuss boards, allowing for faster play.
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A gelatin dessert containing pieces of fruit Prepared commercial blends may be sold as a powder or as a concentrated gelatinous block, divided into small squares. Either type is mixed with sufficient hot water to completely dissolve it, and then mixed with enough cold water to make the volume of liquid specified on the packet. The solubility of powdered gelatin can be enhanced by sprinkling it into the liquid several minutes before heating, "blooming" the individual granules. The fully dissolved mixture is then refrigerated, slowly forming a colloidal gel as it cools.
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The Getå Railroad Disaster () was a train disaster caused by a landslide in Getå, a town that is now part of the municipality of Norrköping on 1 October 1918. To date, it is the worst rail accident in Swedish history. The derailment occurred when the layers of colloidal clay and gravel in the embankment that had been cut into the hill gave way. Shortly afterwards, a mixed train consisting of a locomotive and ten cars came down the tracks, falling down the embankment and landing on the road below.
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Pineapple juice is manufactured from ripe pineapples.Pineapple juice processing complete sets of production lines TICO, Retrieved June 10, 2019 To clean pineapples before juicing, a brush and spray cleaning machine is used to remove stains, imperfections and pesticide residue.Pineapple juice processing line TICO, Retrieved June 10, 2019 After cleaning, the fruit is put into a pineapple peeling and extractor machine to obtain pulps which are put into a spiral juice extractor. A juice fine filter is then used to remove all solids, fiber and colloidal particles from the pineapple juice.
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Figure 1: Schematic representation of an electrofiltration chamber Electrofiltration is a technique for separation and concentration of colloidal substances – for instance biopolymers. The principle of electrofiltration is based on overlaying electric field on a standard dead-end filtration. Thus the created polarity facilitates electrophoretic force which is opposite to the resistance force of the filtrate flow and directs the charged biopolymers. This provides extreme decrease in the film formation on the micro- or ultra-filtration membranes and the reduction of filtration time from several hours by standard filtration to a few minutes by electrofiltration.
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Fabrication of current thin film solar cell technology involves costly evaporation techniques, which is hindering their mass market adoption. CIGS and CIS (copper indium gallium diselenide, copper indium diselenide) nanocrystals or quantum dots allow the use of conventional, low cost printing techniques to fabricate thin film solar cells.Duncan Graham- Rowe: From dots to devices, "Nature Photonics" 3, 307–309 (1 June 2009). Using a colloidal method to make CIGS and CIS nanoparticles for photovoltaic applications provide materials that possess the desired elemental ratios or stoichiometry, which can be adjusted to meet specific needs.
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MXene SERS substrates have been manufactured by spray-coating and were used to detect several common dyes, with calculated enhancement factors reaching ~106. Titanium carbide MXene demonstrates SERS effect in aqueous colloidal solutions, suggesting the potential for biomedical or environmental applications, where MXene can selectively enhance positively charged molecules. Transparent conducting electrodes have been fabricated with titanium carbide MXene showing the ability to transmit approximately 97% of visible light per nanometer thickness. The performance of MXene transparent conducting electrodes depends on the MXene composition as well as synthesis and processing parameters.
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Compared to graphene oxide, which has been widely reported as an antibacterial agent, Ti2C MXene shows lack of antibacterial properties. On the other hand, MXene of Ti3C2 MXene shows a higher antibacterial efficiency toward both Gram-negative E. coli and Gram-positive B. subtilis. Colony forming unit and regrowth curves showed that more than 98% of both bacterial cells lost viability at 200 μg/mL Ti3C2 colloidal solution within 4 h of exposure. Damage to the cell membrane was observed, which resulted in release of cytoplasmic materials from the bacterial cells and cell death.
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The James Clerk Maxwell Foundation was formed in 1977 by the late Sydney Ross,Sydney Ross, Royal Society of Edinburgh, UK. Professor of Colloidal chemistry at Rensselaer Polytechnic Institute in New York, USA. Ross was born in Scotland and he inherited monies from his late father’s whisky business, Ross, Campbell Ltd. In 1993, the Foundation acquired 14 India Street, Edinburgh, the birthplace of Maxwell. Since 1993, the house has been refurbished to its original standard and a small museum has been developed which features Maxwell’s family, life and scientific advances.
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Solubilization is distinct from dissolution because the resulting fluid is a colloidal dispersion involving an association colloid. This suspension is distinct from a true solution, and the amount of the solubilizate in the micellar system can be different (often higher) than the regular solubility of the solubilizate in the solvent. In non-chemical literature and in everyday language, the term "solubilization" is sometimes used in a broader meaning as "to bring to a solution or (non-sedimenting) suspension" by any means, e.g., leaching by a reaction with an acid.
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Normalization is necessary to account for differences in total protein concentration between each sample and so that antibody staining can be directly compared between samples. This can be achieved by performing an experiment in parallel in which total proteins are stained by colloidal gold total protein staining or Sypro Ruby total protein staining. When multiple RPMAs are analyzed, the signal intensity values can be displayed as a heat map, allowing for Bayesian clustering analysis and profiling of signaling pathways. An optimal software tool, custom designed for RPMAs is called Microvigene, by Vigene Tech, Inc.
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It may also be applied to other situations where a continuous medium has smoothly varying density, such as in the case of an inhomogeneous colloidal suspension. In general isopycnic surfaces will occur in fluids in hydrostatic equilibrium coinciding with equipotential surfaces formed by gravity. The term "isopycnic" is also encountered in biophysical chemistry, usually in reference to a process of separating particles, subcellular organelles, or other substances on the basis of their density. Isopycnic centrifugation refers to a method wherein a density gradient is either pre-formed or forms during high speed centrifugation.
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Bottled mineral water usually contains higher TDS levels than tap water Total dissolved solids (TDS) is a measure of the dissolved combined content of all inorganic and organic substances present in a liquid in molecular, ionized, or micro-granular (colloidal sol) suspended form. TDS concentrations are often reported in parts per million (ppm). Water TDS concentrations can be determined using a digital meter. Generally, the operational definition is that the solids must be small enough to survive filtration through a filter with 2-micrometer (nominal size, or smaller) pores.
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Freundlich's main works dealt with the coagulation and stability of colloidal solutions. His most prominent student was Robert Havemann who became a well known colloid chemist of the German Democratic Republic. His work is of continuing importance, with his 1907 paper "Über die Adsorption in Lösungen" (On adsorption in solutions) becoming highly cited at the beginning of the 21st century. This early paper was based on his habilitation thesis written in Leipzig under the guidance of Wilhelm Ostwald, and was heavily based on the work of Sten Lagergren.
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After graduating from Stuyvesant High School in New York City, Paul Chaikin earned his B.S. in physics from California Institute of Technology in 1966, and his Ph.D. in physics from the University of Pennsylvania in 1971 working with Kondo superconductors. He joined the physics faculty at the University of California, Los Angeles in 1972 and studied thermopower, density waves, and high field phenomena mostly in organic superconductors. The lure of actually seeing the microscopics of a system led him to soft matter. He helped develop techniques to measure elasticity and motion and understand colloidal interactions.
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Jubb promotes his view on diet and nutrition via talks, classes, books, and his public television show "The Universe Inside Our Mind". He wrote "Secrets of an Alkaline Body" and "Jubb's Cell Rejuvenation." Designer Donna Karan followed the diet as well as other celebrities. Jubb also maintains a wiki on topics such as “colloidal biology, zero point energy, cellular cleansing, whole brain functioning, lifefood, nutrition, ancient archeology, gender and economic egalitarianism.” He ran a health food store in New York City called Jubbs' Longevity, which is no longer open.
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Preparation of nanoparticles by Laser in Solution Laser ablation synthesis in solution (LASiS) is a commonly used method for obtaining colloidal solution of nanoparticles in a variety of solvents. In the LASiS method, nanoparticles are produced during the condensation of a plasma plume formed by the laser ablation of a bulk metal plate dipped in a liquid solution. LASiS is usually considered a top-down physical approach. In the past years, laser ablation synthesis in solution (LASiS) emerged as a reliable alternative to traditional chemical reduction methods for obtaining noble metal nanoparticles (NMNp).
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In 1926 Jones joined the research staff of Imperial Chemical Industries in Billingham, County Durham. In 1933 he returned to Wales as Research Manager for the Powell Duffryn Coal Company, where he developed 'Phurnacite' smokeless coal briquettes and worked on the manufacturing process for colloidal fuel. On the nationalisation of the British coal industry in 1946, Jones was invited to set up and lead the scientific service, becoming Director General of Research Development (Coal Processing and Combustion) at the National Coal Board. He retired from the National Coal Board in 1963, due to ill health.
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Typical organelles or endosomes enclosed by a lipid bilayer are not considered biomolecular condensates. In addition, lipid droplets are surrounded by a lipid monolayer in the cytoplasm, or in milk, or in tears, so appear to fall under the 'membrane bound' category. Finally, secreted LDL and HDL lipoprotein particles are also enclosed by a lipid monolayer. The formation of these structures involves phase separation to from colloidal micelles or liquid crystal bilayers, but they are not classified as biomolecular condensates, as this term is reserved for non-membrane bound organelles.
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Presence of colloidal calcium carbonate from high concentrations of dissolved lime turns the water of Havasu Falls turquoise. Water is an excellent solvent due to its high dielectric constant. Substances that mix well and dissolve in water are known as hydrophilic ("water-loving") substances, while those that do not mix well with water are known as hydrophobic ("water-fearing") substances. The ability of a substance to dissolve in water is determined by whether or not the substance can match or better the strong attractive forces that water molecules generate between other water molecules.
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The colloidal particles are stable at the normal pH of milk which is 6.5-6.7, the micelles will precipitate at the isoelectric point of milk which is a pH of 4.6. The proteins that make up the remaining 20% of the fraction of proteins in cream are known as whey proteins. Whey proteins are also widely referred to as serum proteins, which is used when the casein proteins have been precipitated out of solution. The two main components of whey proteins in milk are β-lactoglobulin and α-lactalbumin.
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Due to its high specific surface area and its unbalanced negative electric charges, clay is the most active mineral component of soil. It is a colloidal and most often a crystalline material. In soils, clay is a soil textural class and is defined in a physical sense as any mineral particle less than in effective diameter. Many soil minerals, such as gypsum, carbonates, or quartz, are small enough to be classified as clay based on their physical size, but chemically they do not afford the same utility as do mineralogically-defined clay minerals.
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Animal glue in granules Animal glue is an organic colloid of protein derivation used as an adhesive, sizing and coating, compo, and for colloidal applications in industry which is derived primarily from collagenous material present in animal hide or from the extraction of collagen present in animal bones, primarily cattle or derived from recycled gelatin. These protein colloid glues are formed through hydrolysis of the collagen from skins, bones, tendons, and other tissues, similar to gelatin. The word collagen itself derives from Greek , meaning 'glue'. These proteins form a molecular bond with the glued object.
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Colloidal solutions of technetium(IV) chloride are oxidized to form Tc(VII) ions when exposed to gamma rays. Technetium tetrachloride can be synthesized from the reaction of Cl2(g) with technetium metal at elevated temperatures between 300-500 °C: :Tc + 2 Cl2 → TcCl4 Technetium tetrachloride has also been prepared from the reaction of technetium(VII) oxide with carbon tetrachloride in a bomb reaction vessel at elevated temperature and pressure: :Tc2O7 \+ 7 CCl4 → 2 TcCl4 \+ 7 COCl2 \+ 3 Cl2 At 450 °C under vacuum, TcCl4 decomposes to TcCl3 and TcCl2.
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The Ugelstad Laboratory was founded at the Norwegian University of Science and Technology (NTNU), Trondheim, Norway, in January 2002 to commemorate the late Professor John Ugelstad. The laboratory specialises in surfactant chemistry and its technical applications, emulsions and emulsion technology, preparation of polymers and polymer particles - such as the monosized microbeads - and their technical applications, plasma chemical modification of surfaces and silica-based chemistry. Applications include crude oil production and processing, wood pulp and paper, biomedicine, catalysis and material science. The main purpose is to raise the national level of colloidal science.
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In USDA soil taxonomy, Andisols are soils formed in volcanic ash and defined as soils containing high proportions of glass and amorphous colloidal materials, including allophane, imogolite and ferrihydrite. In the World Reference Base for Soil Resources (WRB), Andisols are known as Andosols. Because they are generally quite young, Andisols typically are very fertile except in cases where phosphorus is easily fixed (this sometimes occurs in the tropics). They can usually support intensive cropping, with areas used for wet rice in Java supporting some of the densest populations in the world.
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Mezzenga did postdoctoral research on semiconductive polymer colloids at the University of California and then moved to the Nestlé Research Center in Lausanne as research scientist, working on the self-assembly of surfactants, natural amphiphiles and lyotropic liquid crystals. In 2005 he was hired as Associate Professor in the Physics Department of the University of Fribourg, and he then joined ETH Zurich. on 2009 as Full Professor. His research mainly focuses on the fundamental understanding of self-assembly processes in polymers, lyotropic liquid crystals, biological and food colloidal systems.
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Poly(hydridocarbyne) (PHC) is one of a class of carbon-based random network polymers primarily composed of tetrahedrally hybridized carbon atoms, each having one hydride substituent, exhibiting the generic formula [HC]n. PHC is made from bromoform, a liquid halocarbon that is commercially manufactured from methane. At room temperature, poly(hydridocarbyne) is a dark brown powder. It can be easily dissolved in a number of solvents (tetrahydrofuran, ether, toluene etc.), forming a colloidal suspension that is clear and non- viscous, which may then be deposited as a film or coating on various substrates.
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In many cases, as in various high-temperature catalytic applications of Au, the removal of the capping ligands produces more desirable physicochemical properties. The removal of ligands from colloidal gold while maintaining a relatively constant number of Au atoms per Au NP can be difficult due to the tendency for these bare clusters to aggregate. The removal of ligands is partially achievable by simply washing away all excess capping ligands, though this method is ineffective in removing all capping ligand. More often ligand removal achieved under high temperature or light ablation followed by washing.
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In order to respond to a magnetic field, a matrix can be easily loaded with nanoparticles or nanorods The different morphologies for magnetic nanocomposite materials are vast, including matrix dispersed nanoparticles, core-shell nanoparticles, colloidal crystals, macroscale spheres, or janus-type nanostructures. Magnetic nanocomposites can be utilized in a vast number of applications, including catalytic, medical, and technical. For example, palladium is a common transition metal used in catalysis reactions. Magnetic nanoparticle-supported palladium complexes can be used in catalysis to increase the efficiency of the palladium in the reaction.
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The Tyndall effect in opalescent glass: It appears blue from the side, but orange light shines through. Rayleigh scattering is defined by a mathematical formula that requires the light-scattering particles to be far smaller than the wavelength of the light. For a dispersion of particles to qualify for the Rayleigh formula, the particle sizes need to be below roughly 40 nanometres (for visible light), and the particles may be individual molecules. Colloidal particles are bigger, and are in the rough vicinity of the size of a wavelength of light.
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Each gradient provides a thermodynamic force that moves the species present, and the Onsager reciprocal relations govern the relationship between the forces and the motions. Diffusiophoresis is a special case of multicomponent diffusion. Multicomponent diffusion is diffusion in mixtures, and diffusiophoresis is the special case where we are interested in the movement of one species that is usually a colloidal particle, in a gradient of a much smaller species, such as dissolved salt such as sodium chloride in water. or a miscible liquid, such as ethanol in water.
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The formation of free-floating CdTe nanosheets was due to directional hydrophobic attraction and anisotropic electrostatic interactions caused by dipole moment and small positive charges. Molecular simulations through a coarse-grained model with parameters from semi-empirical quantum mechanics calculations can be used to prove the experimental process. Ultrathin single-crystal PbS (lead sulfur) sheets with micro scale in x-, y- dimensions can be obtained using a hot colloidal synthesis method. Compounds with linear chloroalkanes like 1,2-dichloroethane containing chlorine were used during the formation of PbS sheets.
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Bentonite slurry walls (also known as diaphragm walls ) are used in construction, where the slurry wall is a trench filled with a thick colloidal mixture of bentonite and water. A trench that would collapse due to the hydraulic pressure in the surrounding soil does not collapse as the slurry balances the hydraulic pressure. Forms for concrete, and rebar, can be assembled in a slurry-filled trench, and then have concrete poured into the form. The liquid concrete being denser displaces the less-dense bentonite slurry and causes the latter to overflow from the trench.
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Of interest within the scientific community, when an anomalous-type diffusion process is discovered, the challenge is to understand the underlying mechanism which causes it. There are a number of frameworks which give rise to anomalous diffusion that are currently in vogue within the statistical physics community. These are long range correlations between the signals continuous- time random walks (CTRW ) and fractional Brownian motion (fBm), diffusion of colloidal particles in bacterial suspensions, and diffusion in disordered media. Anomalous subdiffusion in cellular cytosol can be an artifact resulting from using of polydisperse probes for measurements.
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He used this method to directly detect colloidal assembly, their structure, and orientation , which affirmed the spatiotemporal aspects of the method. Breaking the barrier of programmable pulsed laser generation has been concomitant to his insights into the theoretical aspects of pulsed light and heat dissipation dynamics. His work on the cumulative thermal effects of femtosecond infra-red lasers, has revolutionized the existing framework of laser heat dissipation. This has in turn been shown to be the key to mitigating the deleterious effect of heat accumulation during sensitive measurements of nonlinear optical properties.
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Pierre Wiltzius ( Luxembourg - ) is a physicist, the Executive Dean of the College of Letters and Science and Susan & Bruce Worster Dean of Science at the University of California, Santa Barbara and an Elected Fellow of the American Physical Society and of the American Association for the Advancement of Science (Engineering, 1999). His research has varied from photonic crystals and new fabrication techniques such as multi-beam interference lithography and colloidal self-assembly, complex fluids and soft condensed matter, resulting in high citations of 1310, 771 and 537, two of them consistently published by Nature.
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Austinite is a rare mineral in the oxidation zone of arsenic bearing base metal deposits, where it is found developed on the colloform (pertaining to the rounded, globular texture of mineral formed by colloidal precipitation) surface of limonite or lining small cavities. It is closely associated with adamite, and appears to be a later mineral. Austinite is associated with adamite, quartz, talmessite and limonite. Its type locality is Gold Hill Mine (Western Utah Mine), Gold Hill, Gold Hill District (Clifton District), Deep Creek Mts, Tooele County, Utah, US United States.
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However, at concentrations above 1% no such phase separation occurred. Unlike the lower concentrations where the arrangement of clay particles was continually in flux, the particles above 1% concentration locked into a stable structure which is known as equilibrium gel. Clay particles interact in an anisotropic way differing from the typical isotropic way of colloidal particles, which normally interact with all of their nearest neighbors when forming a gel. The clay particles are disc-shaped giving them an asymmetric charge distribution with a net positive charge on their edges and net negative on their faces.
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Equilibrium gel is similar to any gel in the way that it is a colloid in which the disperse phase has combined with the dispersion medium to produce a semisolid material. The difference with equilibrium gel is that it will not separate over time into two separate phase like all other gels. In a study taking place over seven years, scientist concluded that colloidal clays at slightly higher concentrations evolved reversibly and continuously from the empty liquid state to an arrested structure. From this observed properties the name equilibrium gel was derived.
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Edward John Hinch (born 4 March 1947) is a Professor of fluid dynamics at the University of Cambridge, and fellow of Trinity College, Cambridge. His research covers a wide range of fluid dynamics, including micro-hydrodynamics, colloidal dispersion, flow through porous media, polymer rheology and non- Newtonian fluid dynamics. He also works on industrial problems involving fluid dynamics, including collaborating with experimental groups in Paris, Marseille and Toulouse. He lectures undergraduates at the University of Cambridge, is a Director of Studies for Trinity College, and supervises PhD students.
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Matthias Ballauff (born 13 July 1952) is a German chemist and physicist, and is a professor of physics at the Free University of Berlin. His postdoctoral research and training was directed by Paul Flory. He contributed to various areas of physical chemistry, in particular to polymer science, colloidal chemistry and nanomaterials, as well as to soft matter physics. Ballauff is particularly known for having developed new catalyst materials in the form of functionalized metallic nanoparticles dispersed in liquid phase, which can greatly speed up the reaction kinetics of organic molecules.
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Research is in progress to optimize the methodologies for the intracellular delivery of QD and QD bioconjugates, and characterization of long-term in vivo photophysical properties. Quantum dots are colloidal nanocrystals, based on a cadmium- selenium (CdSe) core covered with a zinc-sulfur (ZnS) layer. This substrate has been used intensively as a cellular marker because CdSe emits in the visible domain and is an excellent contrast agent, while the ZnS layer protects the core from oxidation and also the leeching of CdSe into the surrounding solution. This strategy also improves the photo-luminescence yield.
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Basic India ink is composed of a variety of fine soot, known as lampblack, combined with water to form a liquid. No binder material is necessary: the carbon molecules are in colloidal suspension and form a waterproof layer after drying. A binding agent such as gelatin or, more commonly, shellac may be added to make the ink more durable once dried. India ink is commonly sold in bottled form, as well as a solid form as an inkstick (most commonly, a stick), which must be ground and mixed with water before use.
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With his work on the Brownian motions of strongly interacting particles, Pusey was one of the first to apply microscopic approaches to colloidal suspensions. His research exploited analogies and differences between concentrated suspensions of hard-sphere colloids and atomic materials, to investigate such fundamental phenomena as crystallisation, the glass transition and the formation of ordered binary superlattices. With Eric Jakeman, Pusey also introduced K-distributions; these have proved powerful in describing the statistical properties of, for example, microwaves scattered by the sea surface and laser light propagating through the atmosphere.
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Moore's team has developed sensors that can detect and respond to mechanical force. For example, a molecular probe can undergo a color change to signal possible damage. In 2005, Moore, Jennifer A. Lewis and others demonstrated a light-sensitive monolayer that could be used to design colloidal fluids, gels and crystals whose surface charge and chemical structure would change depending on their exposure to ultraviolet light. More recently Moore and others have created heat-sensitive microspheres that react to conditions such as thermal runaway in lithium-ion batteries.
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Humus refers to organic matter that has been decomposed by soil microflora and fauna to the point where it is resistant to further breakdown. Humus usually constitutes only five percent of the soil or less by volume, but it is an essential source of nutrients and adds important textural qualities crucial to soil health and plant growth. Humus also feeds arthropods, termites and earthworms which further improve the soil. The end product, humus, is suspended in colloidal form in the soil solution and forms a weak acid that can attack silicate minerals.
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She graduated summa cum laude and was inducted into Phi Beta Kappa and Sigma Xi. She received her Ph.D. in Chemistry at the University of Illinois at Urbana-Champaign in the laboratory of Kenneth Suslick (2006). Her thesis research focused on the aerosol synthesis of porous materials, and she was the recipient of the T. S. Piper Thesis Research Award from the Chemistry Department. Her postdoctoral research was conducted at the University of Washington with Xingde Li and Younan Xia. There she was introduced to colloidal metal nanoparticle synthesis and their biomedical applications.
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After further refinements included in a 1928 patent application, Tihanyi's patent was declared void in Great Britain in 1930,Tihanyi, Koloman, Improvements in television apparatus. European Patent Office, Patent No. GB313456. Convention date UK application: 1928-06-11, declared void and published: 1930-11-11, retrieved: 2013-04-25. and so he applied for patents in the United States. In 1923, while employed by the Westinghouse Electric Corporation in Pittsburgh, Pennsylvania, Russian- born American engineer Vladimir Zworykin presented a project for a totally electronic television system to the company's general manager. In July 1925, Zworykin submitted a patent application titled Television System that included a charge storage plate constructed of a thin layer of isolating material (aluminum oxide) sandwiched between a screen (300 mesh) and a colloidal deposit of photoelectric material (potassium hydride) consisting of isolated globules. The following description can be read between lines 1 and 9 in page 2: "The photoelectric material, such as potassium hydride, is evaporated on the aluminum oxide, or other insulating medium, and treated so as to form a colloidal deposit of potassium hydride consisting of minute globules. Each globule is very active photoelectrically and constitutes, to all intents and purposes, a minute individual photoelectric cell".
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The latter has two effects. It allows water to flow more freely and it reduces the colloidal or oncotic pressure difference by allowing protein to leave the vessel more easily. Another set of vessels known as the lymphatic system acts like an "overflow" and can return much excess fluid to the bloodstream. But even the lymphatic system can be overwhelmed, and if there is simply too much fluid, or if the lymphatic system is congested, then the fluid will remain in the tissues, causing swellings in legs, ankles, feet, abdomen or any other part of the body.
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This triggered a re-evaluation of the well-established notion that . In 1998 experiments were carried out to repeat the studies of Aschoff, following exactly the original methods description, and using modern ways of identifying the cells that were responsible for clearance of intravascularly injected colloidal lithium carmine, the most commonly used vital stain. The studies showed that the cell system that Aschoff described as RES in the liver were liver sinusoidal endothelial cells (LSECs), but not liver macrophages (Kupffer cells). In most present-day text books and articles the term RES is used synonymously with MPS.
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Since then, the research group of Kovalenko has focused on understanding and improving colloidal perovskite nanocrystals, their assembly into long-range ordered superlattices and their exploration as quantum light sources. Additionally, the group continues to investigate the surface chemistry of nanocrystals and novel electrode materials for Li-ion and non-Li battery technologies. The group is increasingly active in the discovery of novel semiconductors and light emitters. In 2018, the group received financial support from the ETH+ Initiative to establish a crystal growth and characterization facility for research purposes as well as for education and training of students.
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The most common methods for nanoparticle synthesis fall under the category of wet chemistry, or the nucleation of particles within a solution. This nucleation occurs when a silver ion complex, usually AgNO3 or AgClO4, is reduced to colloidal silver in the presence of a reducing agent. When the concentration increases enough, dissolved metallic silver ions bind together to form a stable surface. The surface is energetically unfavorable when the cluster is small, because the energy gained by decreasing the concentration of dissolved particles is not as high as the energy lost from creating a new surface.
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There are detailed descriptions of the interfacial DL in many books on colloid and interface scienceDukhin, S.S. & Derjaguin, B.V. "Electrokinetic Phenomena", J.Willey and Sons, 1974Russel, W.B., Saville, D.A. and Schowalter, W.R. "Colloidal Dispersions", Cambridge University Press,1989Kruyt, H.R. "Colloid Science", Elsevier: Volume 1, Irreversible systems, (1952) and microscale fluid transport. There is also a recent IUPAC technical report"Measurement and Interpretation of Electrokinetic Phenomena", International Union of Pure and Applied Chemistry, Technical Report, published in Pure Appl.Chem., vol 77, 10, pp.1753-1805, 2005 (pdf) on the subject of interfacial double layer and related electrokinetic phenomena.
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A noticeable side-effect of gold-based therapy is skin discoloration, in shades of mauve to a purplish dark grey when exposed to sunlight. Skin discoloration occurs when gold salts are taken on a regular basis over a long period of time. Excessive intake of gold salts while undergoing chrysotherapy results – through complex redox processes – in the saturation by relatively stable gold compounds of skin tissue and organs (as well as teeth and ocular tissue in extreme cases) in a condition known as chrysiasis. This condition is similar to argyria, which is caused by exposure to silver salts and colloidal silver.
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Polyphenols are an important component of ciders, contributing astringency, bitterness, colloidal stability and colour. The content in apples varies depending on cultivar, production practices, and part of the fruit, with the peel of an apple having more polyphenols than the flesh. The primary polyphenol in apples is procyanidins, followed by hydroxycinnamic acids in the flesh and flavonols in peel. Much of the polyphenols in the fruit are not pressed into the juice, because they bind to polysaccharides in the fruit cell wall, becoming bound to the pomace, when the cell wall is ruptured during the pressing process.
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Virtually all money is made by selling Jones's dietary supplements to viewers and listeners through the site's online store. The supplements sold on the InfoWars store are primarily sourced from Dr. Edward F. Group III, a chiropractor who founded the Global Healing Center supplement vendor. A significant portion of InfoWarss products contain colloidal silver, which Jones falsely claimed "kills every virus", including "the whole SARS-corona family"; this claim was disputed by the Food and Drug Administration (FDA). A lesser source of revenue for InfoWars is its "money bomb" telethons, which resemble public radio fundraisers, except InfoWars is a for-profit institution.
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2, page.3.208, 1995 Russel, W.B., Saville, D.A. and Schowalter, W.R. "Colloidal Dispersions", Cambridge University Press, 1992 Dukhin, A. S. and Goetz, P. J. Characterization of liquids, nano- and micro- particulates and porous bodies using Ultrasound, Elsevier, 2017 Hunter, R.J. "Foundations of Colloid Science", Oxford University Press, 1989 There is an IUPAC Technical Report prepared by a group of world experts on the electrokinetic phenomena. From the instrumental viewpoint, there are three different experimental techniques: microelectrophoresis, electrophoretic light scattering, and tunable resistive pulse sensing. Microelectrophoresis has the advantage of yielding an image of the moving particles.
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In 2003 his group has reported the first successful growth of colloidal zinc-blende lattice III-V semiconductor nanorods. Continuing the work on III-V semiconductor nanocrystals, the group has published the synthesis of bright near-infrared-emitting core/shell nanocrystals, later employing them in a novel nanocrystal-polymer near- infrared light-emitting diode. In 2011 the group reported a simple procedure for the doping on nanocrystals, allowing the synthesis of heavily-doped p-type and n-type semiconductor nanocrystals. Some of his earlier works include the study of cadmium chalcogenide molecular clusters as a step between complexes and nanocrystals with semiconducting properties.
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They have been the subject of detailed studies for many years. However, the mobility of inorganic colloids is very low in compacted bentonites and in deep clay formations because of the process of ultrafiltration occurring in dense clay membrane. The question is less clear for small organic colloids often mixed in porewater with truly dissolved organic molecules. In soil science, the colloidal fraction in soils consists of tiny clay and humus particles that are less than 1μm in diameter and carry either positive and/or negative electrostatic charges that vary depending on the chemical conditions of the soil sample, i.e.
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Besides pzc, iep, and cip, there are also numerous other terms used in the literature, usually expressed as initialisms, with identical or (confusingly) near-identical meaning: zero point of charge (zpc), point of zero net charge (pznc), point of zero net proton charge (pznpc), pristine point of zero charge (ppzc), point of zero salt effect (pzse), zero point of titration (zpt) of colloidal dispersion, and isoelectric point of the solid (ieps)Marek Kosmulski, "Chemical Properties of Material Surfaces", Marcel Dekker Inc., 2001. and point of zero surface tension (pzstJean-Pierre Jolivet, "Metal Oxide Chemistry and Synthesis", John Wiley & Sons, 2000. or pzsR.
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Colloidal quantum dots irradiated with a UV light. Different sized quantum dots emit different color light due to quantum confinement. A quantum dot display is a display device that uses quantum dots (QD), semiconductor nanocrystals which can produce pure monochromatic red, green, and blue light. Photo-emissive quantum dot particles are used in a QD layer which uses the blue light from a backlight to emit pure basic colors which improve display brightness and color gamut by reducing light losses and color crosstalk in RGB LCD color filters, replacing traditional colored photoresists in RGB LCD color filters.
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The plant monographs with dermatological relevance of the former German Commission E have recently been reviewed. According to Baumann, "Botanical compounds for which dermatologic and cosmetic applications have emerged include: olive oil, chamomile, colloidal oatmeal, oat kernel extract, feverfew, acai berry, coffee berry, curcumin, green tea, pomegranate, licorice, paper mulberry, arbutin, and soy. "Many of these botanical sources offer biologically active components that require further in vitro and in vivo investigation". A review of 35 plant families found that a "variety of phytomolecules, derived in particular from polyphenols, triterpenes and sterols classes, demonstrated a promising activity.
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In his opinion, these were the raw materials for the evolution of life. # In Oparin's formulation, there were first only simple solutions of organic matter, the behavior of which was governed by the properties of their component atoms and the arrangement of these atoms into a molecular structure. Gradually though, he said, the resulting growth and increased complexity of molecules brought new properties into being and a new colloidal-chemical order developed as a successor to more simple relationships between and among organic chemicals. These newer properties were determined by the interactions of these more complex molecules.
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Secondary treatment is a treatment process for wastewater (or sewage) to achieve a certain degree of effluent quality by using a sewage treatment plant with physical phase separation to remove settleable solids and a biological process to remove dissolved and suspended organic compounds. After this kind of treatment, the wastewater may be called as secondary-treated wastewater. Secondary treatment is the portion of a sewage treatment sequence removing dissolved and colloidal compounds measured as biochemical oxygen demand (BOD). Secondary treatment is traditionally applied to the liquid portion of sewage after primary treatment has removed settleable solids and floating material.
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In the EC process, the coagulant is generated in situ by electrolytic oxidation of an appropriate anode material. In this process, charged ionic species—metals or otherwise—are removed from wastewater by allowing it to react with an ion having an opposite charge, or with floc of metallic hydroxides generated within the effluent. Electrocoagulation offers an alternative to the use of metal salts or polymers and polyelectrolyte addition for breaking stable emulsions and suspensions. The technology removes metals, colloidal solids and particles, and soluble inorganic pollutants from aqueous media by introducing highly charged polymeric metal hydroxide species.
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Uranyl hydroxide is a hydroxide of uranium with the chemical formula UO2(OH)2 in the monomeric form and (UO2)2(OH)4 in the dimeric; both forms may exist in normal aqueous media. Uranyl hydroxide hydrate is precipitated as a colloidal yellowcake from oxidized uranium liquors near neutral pH. Uranyl hydroxide was once used in glassmaking and ceramics in the colouring of the vitreous phases and the preparation of pigments for high temperature firing. The introduction of alkaline diuranates into glasses leads to yellow by transmission, green by reflection; moreover these glasses become dichroic and fluorescent under ultraviolet rays.
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In this regime, smaller particles grow faster than large ones (since larger crystals need more atoms to grow than small crystals) resulting in the size distribution focusing, yielding an improbable distribution of nearly monodispersed particles. The size focusing is optimal when the monomer concentration is kept such that the average nanocrystal size present is always slightly larger than the critical size. Over time, the monomer concentration diminishes, the critical size becomes larger than the average size present, and the distribution defocuses. Cadmium sulfide quantum dots on cells There are colloidal methods to produce many different semiconductors.
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Quantum dot photodetectors (QDPs) can be fabricated either via solution- processing, or from conventional single-crystalline semiconductors. Conventional single-crystalline semiconductor QDPs are precluded from integration with flexible organic electronics due to the incompatibility of their growth conditions with the process windows required by organic semiconductors. On the other hand, solution-processed QDPs can be readily integrated with an almost infinite variety of substrates, and also postprocessed atop other integrated circuits. Such colloidal QDPs have potential applications in visible- and infrared-light cameras,Palomaki P.; and Keuleyan S. (2020): Move over CMOS, here come snapshots by quantum dots.
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Two images produced using immunogold labeling and transmission electron microscopy: (A) Gold particles are marking mtDNA near the mitochondria (B) mtDNA marked with gold particles after extraction.Immunogold labeling or Immunogold staining (IGS) is a staining technique used in electron microscopy. This staining technique follow the same patterns of the Indirect immunofluorescence: colloidal gold particles are most often attached to secondary antibodies which are in turn attached to primary antibodies designed to bind a specific antigen or other cell component. Gold is used for its high electron density which increases electron scatter to give high contrast 'dark spots'.
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Although true endothelial cells are only found in vertebrates, insect hemocytes and nephrocytes have similar scavenger functions to vertebrate macrophages and SECs, sharing the task of waste clearance and defense against foreign intruders. Colloidal vital dyes, such as ammonia carmine and trypan blue, are rapidly and preferentially taken up by insect pericardial and garland nephrocytes. Nephrocytes, but not hemocytes of the common blow fly (Calliphora) avidly endocytose and degrade ligands that are also recognized by stabilin-2 of mammalian scavenger endothelial cells. In Drosophila, nephrocytes remove microbiota-derived peptidoglycan from systemic circulation to maintain immune homeostasis.
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The nano-PV solar cell class includes a variety of solar cells including molecular, organic, polymeric, dye-sensitized, and colloidal quantum dot (CQD) PVs. As light passes throughout the transparent solar cell NIR is absorbed, then with the incorporation of NIR reflecting mirrors, there is better PCE and optimization of performance. The OPVs are made on glass, pre-coated with 150 nm thick idium-tin oxide (ITO). Then 20 nm Molybdenum trioxide (MoO3), 15 nm chloroaluminum phthalocyanine (ClAlPc), 30 nm Buckminsterfullerene (C60), 7.5 nm bathocuproine (BCP), and 100 nm thick Ag cathode are added through thermal evaporation.
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Association theory (also aggregate theory) is a theory first advanced by chemist Thomas Graham in 1861 to describe the molecular structure of colloidal substances such as cellulose and starch, now understood to be polymers. Association theory postulates that such materials are solely composed of a collection of smaller molecules bound together by an unknown force. Graham termed these materials colloids. Prior to the development of macromolecular theory by Hermann Staudinger in the 1920s, which stated that individual polymers are composed of chains of covalently bonded monomers, association theory remained the most prevalent model of polymer structure in the scientific community.
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A549 cells under DIC microscopy, from a 3-4 days old culture, showing an abundance of intercellular connections, including possible cytonemes, filopodia and other epithelial bridges. (These cells have endocytosed 25x73 nm colloidal gold nanorods.) A549 cells are adenocarcinomic human alveolar basal epithelial cells, and constitute a cell line that was first developed in 1972 by D. J. Giard, et al. through the removal and culturing of cancerous lung tissue in the explanted tumor of a 58-year-old caucasian male. The cells are used as models for the study of lung cancer and the development of drug therapies against it.
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Cueva de Villa Luz (English: Cave of the Lighted House), also known as Cueva del Azufre and Cueva de las Sardinas, is a cave near Tapijulapa in the southern Mexican state of Tabasco. The springs within the cave are rich in hydrogen sulfide, a gas that is a potent respiratory toxicant and smells like rotten eggs. Within the water sulfide is oxidized to colloidal sulfur which gives the water a milky appearance, and creates sulfuric acid. The cave is essentially a maze about two kilometers in length and primarily etched out of limestone by the sulfuric acid in the water.
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Optoelectrofluidics, also known as optically induced electrohydrodynamics, refers to the study of the motions of particles or molecules and their interactions with optically-induced electric field and the surrounding fluid. This concept includes electrothermal vortex, electrophoresis, dielectrophoresis, and electroosmosis induced by combination of optical and electrical energy or by optical-electrical energy transfer. In 1995, an electrothermal vortices induced by a strong IR (infrared) laser projected into an electric field have been utilized to concentrate microparticles and molecules. In 2000, UV(ultraviolet) pattern projected onto ITO (indium tin oxide) electrode has been applied for patterning colloidal particles.
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Blood is a body fluid in humans and other animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells. In vertebrates, it is composed of blood cells suspended in blood plasma. Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume), and contains proteins, glucose, mineral ions, hormones, carbon dioxide (plasma being the main medium for excretory product transportation), and blood cells themselves. Albumin is the main protein in plasma, and it functions to regulate the colloidal osmotic pressure of blood.
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Many forms of medication (from antibiotics to chemotherapy) are administered intravenously, as they are not readily or adequately absorbed by the digestive tract. After severe acute blood loss, liquid preparations, generically known as plasma expanders, can be given intravenously, either solutions of salts (NaCl, KCl, CaCl2 etc.) at physiological concentrations, or colloidal solutions, such as dextrans, human serum albumin, or fresh frozen plasma. In these emergency situations, a plasma expander is a more effective life-saving procedure than a blood transfusion, because the metabolism of transfused red blood cells does not restart immediately after a transfusion.
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This cranberry glass bowl was made by adding a gold salt (probably gold chloride) to molten glass. Used since ancient times as a method of staining glass colloidal gold was used in the 4th-century Lycurgus Cup, which changes color depending on the location of light source. During the Middle Ages, soluble gold, a solution containing gold salt, had a reputation for its curative property for various diseases. In 1618, Francis Anthony, a philosopher and member of the medical profession, published a book called Panacea Aurea, sive tractatus duo de ipsius Auro Potabili (Latin: gold potion, or two treatments of potable gold).
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At the moment, there are scientists working on focused evanescent fields as well. Another approach that has been recently proposed makes use of surface plasmons, which is an enhanced evanescent wave localized at a metal/dielectric interface. The enhanced force field experienced by colloidal particles exposed to surface plasmons at a flat metal/dielectric interface has been for the first time measured using a photonic force microscope, the total force magnitude being found 40 times stronger compared to a normal evanescent wave. By patterning the surface with gold microscopic islands it is possible to have selective and parallel trapping in these islands.
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SEM is able to detect the surface of cellular components in high resolution. This immunolabeling technique is very similar to the immuno-fluorescence method, but a colloidal gold tag is used instead of a fluorophore. Overall, the concepts are very parallel in that an unconjugated primary antibody is used and sequentially followed by a tagged secondary antibody that works against the primary antibody. Sometimes SEM in conjunction with gold particle immunolabeling is troublesome in regards to the particles and charges resolution under the electron beam; however, this resolution setback has been resolved by the improvement of the SEM instrumentation by backscattered electron imaging.
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The depletion force is described as an entropic force because it is fundamentally a manifestation of the second law of thermodynamics, which states that a system tends to increase its entropy. The gain in translational entropy of the depletants, owing to the increased available volume, is much greater than the loss of entropy from flocculation of the colloids. The positive change in entropy lowers the Helmholtz free energy and causes colloidal flocculation to happen spontaneously. The system of colloids and depletants in a solution is modeled as a canonical ensemble of hard spheres for statistical determinations of thermodynamic quantities.
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The understanding of the reactions of clay minerals with water (intercalation, adsorption, colloidal dispersion, etc.) are indispensable for the ceramic industry (plasticity and flow control of ceramic raw mixtures, for example). Those interactions also influence a great number of mechanical properties of soils, being carefully studied by building and construction engineering specialists. The interactions of clay minerals with organic substances in the soil also plays a vital role in the fixation of nutrients and fertility, as well as in the fixation or leaching of pesticides and other contaminants. Some clay minerals (Kaolinite) are used as carrier material for fungicides and insecticides.
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Crowding can promote formation of a biomolecular condensate by colloidal phase separation. This crowding effect can make molecules in cells behave in radically different ways than in test- tube assays. Consequently, measurements of the properties of enzymes or processes in metabolism that are made in the laboratory (in vitro) in dilute solutions may be different by many orders of magnitude from the true values seen in living cells (in vivo). The study of biochemical processes under realistically crowded conditions is very important, since these conditions are a ubiquitous property of all cells and crowding may be essential for the efficient operation of metabolism.
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Polyvalent DNA gold nanoparticles, now more commonly referred to as spherical nucleic acids,Cutler, J. I.; Auyeung, E.; Mirkin, C. A. “Spherical Nucleic Acids,” Journal of the American Chemical Society, 2012, 134, 1376–1391, doi: 10.1021/ja209351u. (Fig. 1) are colloidal gold particles densely modified with short (typically ~30-mer or less), highly oriented, synthetic DNA strands. They were invented by Chad Mirkin et al. at Northwestern University in 1996.Mirkin, C. A.; Letsinger, R. L.; Mucic, R. C; Storhoff, J. J. “A DNA- based method for rationally assembling nanoparticles into macroscopic materials,” Nature, 1996, 382, 607-609, doi: 10.1038/382607a0.
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Interface and colloid science has applications and ramifications in the chemical industry, pharmaceuticals, biotechnology, ceramics, minerals, nanotechnology, and microfluidics, among others. There are many books dedicated to this scientific discipline,Lyklema, J. “Fundamentals of Interface and Colloid Science”, vol.2, page.3.208, 1995 Russel, W.B., Saville, D.A. and Schowalter, W.R. “Colloidal Dispersions”, Cambridge University Press, 1992 Dukhin, A. S. and Goetz, P. J. Characterization of liquids, nano- and micro- particulates and porous bodies using Ultrasound, Elsevier, 2017 and there is a glossary of terms, Nomenclature in Dispersion Science and Technology, published by the US National Institute of Standards and Technology.
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It has been used to measure and monitor the progression of chemical reactions, such as the setting and hardening of concrete from cement paste to solid. Acoustic spectrometry has also been used to measure the volume fraction of colloids in a dispersion medium, as well as for the investigation of physical properties of colloidal dispersions, such as aggregation and particle size distribution. Typically, these experiments are carried out with sinusoidal excitation signals and the experimental observation of signal attenuation. From a comparison of theoretical attenuation to experimental observation, the particle size distribution and aggregation phenomena are inferred.
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Interpolymer complexes could be prepared either by mixing complementary polymers in solutions or by matrix (template) polymerisation. It is also possible to prepare IPCs at liquid-liquid interfaces or at solid or soft surfaces. Usually the structure of IPCs formed will depend on many factors, including the nature of interacting polymers, concentrations of their solutions, nature of solvent, presence of inorganic ions or organic molecules in solutions, etc. Mixing of dilute polymer solutions usually leads to formation of IPCs as a colloidal dispersion, whereas more concentrated polymer solutions form IPCs in the form of a gel.
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Fractional diffusion equations were introduced in order to characterize anomalous diffusion phenomena. Recently, anomalous diffusion was found in several systems including ultra-cold atoms, scalar mixing in the interstellar medium, telomeres in the nucleus of cells, ion channels in the plasma membrane, colloidal particle in the cytoplasm, moisture transport in cement-based materials, and worm-like micellar solutions. Anomalous diffusion was also found in other biological systems, including heartbeat intervals and in DNA sequences. The daily fluctuations of climate variables such as temperature can be regarded as steps of a random walker or diffusion and have been found to be anomalous.
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Thus, the ordinary concrete transforms to nanoconcrete. The initial natural process of cement hydration with formation of colloidal globules about 5 nm in diameter spreads into the entire volume of cement–water matrix as the energy expended upon the mix. The liquid activated high-energy mixture can be used by itself for casting small architectural details and decorative items, or foamed (expanded) for lightweight concrete. HEM Nanoconcrete hardens in low and subzero temperature conditions because the liquid phase inside the nano-pores of C-S-H gel doesn't freeze at temperatures from −8 to −42 degrees Celsius.
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Gastric dilatation volvulus is an emergency medical condition: having the animal examined by a veterinarian is imperative. GDV can become fatal within a matter of minutes. Treatment usually involves resuscitation with intravenous fluid therapy, usually a combination of isotonic fluids and hypertonic saline or a colloidal solution such as hetastarch, and emergency surgery. The stomach is initially decompressed by passing a stomach tube, or if that is not possible, trocars can be passed through the skin into the stomach to remove the gas, alternatively the trocars may be inserted directly into the stomach following anaesthesia in order to reduce the chances of infection.
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The sample pad of this kit contains colloidal gold-anti-human IgG or gold-anti-human IgM. If the sample contains IgG and IgM antibodies against those antigens then they will react and get turned into red color. This complex will continue to move forward and the IgG and IgM antibodies will get attached to the first test line where IgG and IgM antigens are present giving a pink-purplish colored band. This complex will continue to move further and reach the control line which consists of rabbit anti-mouse antibody which bends the mouse anti-human IgG or IgM antibodies.
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Assuming, however, that we are operating at speeds below vc and above those which produce a planar front, we will achieve some cellular structure with both ice-crystals and walls composed of packed ceramic particles. The morphology of this structure is tied to some variables, but the most influential is the temperature gradient as a function of time and distance along the freezing direction. Freeze-cast structures have at least three apparent morphological regions., Morphological instability in freezing colloidal suspensions At the side where freezing initiates is a nearly isotropic region with no visible macropores dubbed the Initial Zone (IZ).
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They showed that tuning the volume fraction of particles in solution will control the specific location along the varying meniscus thickness at which assembly occurs. Particles will align with their long axis in- or out-of-plane depending on whether or not their longer dimension of the particle was equal to the thickness of the wetting layer at the meniscus location. Such thickness transitions were established with spherical particles as well. It was later shown that convective assembly could control particle orientation in assembling multi-layers, resulting in long-range 3D colloidal crystals from dumbbell shaped particles.
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The utilization of gold in skin care and cosmetics dates back at least to the 1st century B.C in Egypt, where Queen Cleopatra is said to have used masks made from gold to maintain her skin complexion. It was said that she used it every night to enhance her complexion and improve the suppleness of her skin. Nowadays, gold has made its way into various skincare products such as lotion and cream, as well as skincare treatments such as facial masks. Gold in skincare products are usually in the form of colloidal gold, or more commonly called nanogold.
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The term "reticuloendothelial system" (abbreviated RES), often associated nowadays with the mononuclear phagocyte system (MPS), was originally launched by the beginning of the 20th century to denote a system of specialised cells that effectively clear colloidal vital stains (so called because they stain living cells) from the blood circulation. The term is still used today, but its meaning has changed over the years, and is used inconsistently in present- day literature. Although RES is commonly associated exclusively with macrophages, recent research has revealed that the cells that accumulate intravenously administrated vital stain belong to a highly specialised group of cells called scavenger endothelial cells (SECs), that are not macrophages.
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The process yielded of rubidium chloride and of caesium chloride from the initial 44,000 litres of mineral water. From the caesium chloride, the two scientists estimated the atomic weight of the new element at 123.35 (compared to the currently accepted one of 132.9). They tried to generate elemental caesium by electrolysis of molten caesium chloride, but instead of a metal, they obtained a blue homogeneous substance which "neither under the naked eye nor under the microscope showed the slightest trace of metallic substance"; as a result, they assigned it as a subchloride (). In reality, the product was probably a colloidal mixture of the metal and caesium chloride.
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In certain conditions, for example when the cation of the inner electrolyte is Cu2+ or Ag2+, regular sheets consisting of colloidal grains are formed . This phenomenon is especially striking when the reactions run in poly(vinyl)alcohol gels, and the speed of the precipitation front falls below about 0.3 μm/s. The finest microscopic patterns have been observed in the NaOH+AgNO3 reactions, where the periodicity dropped below 10 μm. The chemical mechanism of this pattern formation is not fully understood, but computer simulations based on phase separation described by the Cahn-Hilliard equation with a moving source front exhibit the most important properties of the building of the microscopic patterns .
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Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution. In chemistry, a colloid is a phase separated mixture in which one substance of microscopically dispersed insoluble or soluble particles is suspended throughout another substance. Sometimes the dispersed substance alone is called the colloid; the term colloidal suspension refers unambiguously to the overall mixture (although a narrower sense of the word suspension is distinguished from colloids by larger particle size). Unlike a solution, whose solute and solvent constitute only one phase, a colloid has a dispersed phase (the suspended particles) and a continuous phase (the medium of suspension) that arise by phase separation.
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The Kodak verifax, is a photo copying approach that uses a wet colloidal diffusion transfer technique patented by Yutzy, H.C. and Yackel, E.C. (1947) The light source is projected to the top crossing the negative being reflected -more or less, according to the color- against the original to be copied exposing the negative. Has a base that contains the recipient with the liquid developer and the exposure Timer. Due to its extreme simplicity was widespread until the late 60's, when it was surpassed by the popularity of the xerocopies using plain paper. Copies had some chemical smell and lost contrast over the time.
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The Attock Oil Company at Rawalpindi (representative of Messers Steel Brothers & Co London) had confronted a peculiar problem, wherein the mud used for the drilling operation was hardened upon contact with saline water, thereby clogging the drill holes. Shanti Swaroop Bhatnagar realised that this problem could be solved by colloidal chemistry. He added an Indian gum, which had the remarkable property of lowering the viscosity of the mud suspension and of increasing at the same time its stability against the flocculating action of electrolytes. M/s Steel Brothers was so pleased that they offered Shanti Swaroop Bhatnagar a sum of Rs. 1,500,000/- for research work on any subject related to petroleum.
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Protein A is often coupled to other molecules such as a fluorescent dye, enzymes, biotin, colloidal gold or radioactive iodine without affecting the antibody binding site. Examples including protein A–gold (PAG) stain is used in immunogold labelling, fluorophore coupled protein A for immunofluorescence, and DNA docking strand coupled protein A for DNA-PAINT imaging. It is also widely utilized coupled to magnetic, latex and agarose beads. Protein A is often immobilized onto a solid support and used as reliable method for purifying total IgG from crude protein mixtures such as serum or ascites fluid, or coupled with one of the above markers to detect the presence of antibodies.
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The solution of silica is mixed with a catalyst and allowed to gel during a hydrolysis reaction which forms particles of silicon dioxide. The oxide suspension begins to undergo condensation reactions which result in the creation of metal oxide bridges (either M–O–M, "oxo" bridges, or M–OH–M, "ol" bridges) linking the dispersed colloidal particles. These reactions generally have moderately slow reaction rates, and as a result either acidic or basic catalysts are used to improve the processing speed. Basic catalysts tend to produce more transparent aerogels and minimize the shrinkage during the drying process and also strengthen it to prevent pore collapse during drying.
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Alum [Al2(SO4)3.18H2O] is such a chemical substance, which has been widely used for ages for wastewater treatment. The mechanism of coagulation has been the subject of continual review. It is generally accepted that coagulation is brought about primarily by the reduction of the net surface charge to a point where the colloidal particles, previously stabilized by electrostatic repulsion, can approach closely enough for van der Waals forces to hold them together and allow aggregation. The reduction of the surface charge is a consequence of the decrease of the repulsive potential of the electrical double layer by the presence of an electrolyte having opposite charge.
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Polymers on the surfaces of the colloidal fraction of soils promote steric stabilization of those particles by preventing them from approaching each other and aggregating. This effect is seen in a variety of aqueous and nonaqueous environments, and is not affected by electrolytes in solution. The degree of steric stabilization depends on the amount of clay surface covered by adsorbed polymers, the strength of the polymer bond, the thickness of the polymer layer, and the favorability of the solvent for the polymer loops and tails. Block and graft copolymers, made up of two different homopolymers with differing solubilities in the suspension medium, are most often used for steric stabilization.
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The technology can remove several anions, especially arsenate and arsenite (two common species present in arsenic-contaminated water) and fluoride from water. Currently, this technology is delivering arsenic-free water to about 10,00,000 people every day. AMRIT uses an adsorbent based on a simple method to maintain the metastable 2-line ferrihydrite (named as CM2LF) phase at room temperature, by confining it in biopolymeric cages. It can handle concentrations of arsenic and colloidal iron reaching up to 100-800 µg/L and 50 mg/L, respectively and brings the output concentration below the permissible limit set by EPA of 10 µg/L and 200 µg/L, respectively.
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Dr. David Jubb scientist, neurobehavioral physiologist, plasma physicist, microscopist, foremost expert in blood formation, a trained shaman in the native Toltec tradition, innovator in the field of neurology, language and communication; health and beauty industry and Doula. One of the worlds top naturalists who conducts trainings and seminars around the world on cleansing, vitality, whole brain function, whole body calibration, vitality, and a diet based on life food. Dr. David Jubb is the inventor and worlds foremost authority and founder of colloidal biology(understanding the life below the cell). His prime time public television show; "The Universe Inside Our Mind" ran on Manhattan cable for over a decade.
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Therefore, the mix of species is partly determined by the tolerances of individual species to physical conditions, such as tidal flooding and salinity, but may also be influenced by other factors, such as crabs preying on plant seedlings. Once established, mangrove roots provide an oyster habitat and slow water flow, thereby enhancing sediment deposition in areas where it is already occurring. The fine, anoxic sediments under mangroves act as sinks for a variety of heavy (trace) metals which colloidal particles in the sediments have scavenged from the water. Mangrove removal disturbs these underlying sediments, often creating problems of trace metal contamination of seawater and organisms of the area.
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Plutonium is known to bind to soil particles very strongly (see above for an X-ray spectroscopic study of plutonium in soil and concrete). While caesium has very different chemistry to the actinides, it is well known that both caesium and many of the actinides bind strongly to the minerals in soil. Hence it has been possible to use 134Cs labeled soil to study the migration of Pu and Cs in soils. It has been shown that colloidal transport processes control the migration of Cs (and will control the migration of Pu) in the soil at the Waste Isolation Pilot Plant according to R.D. Whicker and S.A. Ibrahim.
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This will crosslink the polymer and allows the coating, which will be porous due to the evolution of gas during the deposition process, to flow out and become smooth and continuous. During the EPD process itself, direct current is applied to a solution of polymers with ionizable groups or a colloidal suspension of polymers with ionizable groups which may also incorporate solid materials such as pigments and fillers. The ionizable groups incorporated into the polymer are formed by the reaction of an acid and a base to form a salt. The particular charge, positive or negative, which is imparted to the polymer depends on the chemical nature of the ionizable group.
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Changes in the apparent color of a gold nanoparticle solution can also be caused by the environment in which the colloidal gold is suspended The optical properties of gold nanoparticles depends on the refractive index near the nanoparticle surface, therefore both the molecules directly attached to the nanoparticle surface (i.e. nanoparticle ligands) and/or the nanoparticle solvent both may influence observed optical features. As the refractive index near the gold surface increases, the NP LSPR will shift to longer wavelengths In addition to solvent environment, the extinction peak can be tuned by coating the nanoparticles with non-conducting shells such as silica, bio molecules, or aluminium oxide.
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After initial nanoparticle synthesis, colloidal gold ligands are often exchanged with new ligands designed for specific applications. For example, Au NPs produced via the Turkevich-style (or Citrate Reduction) method are readily reacted via ligand exchange reactions, due to the relatively weak binding between the carboxyl groups and the surfaces of the NPs. This ligand exchange can produce conjugation with a number of biomolecules from DNA to RNA to proteins to polymers (such as PEG) to increase biocompatibility and functionality. For example, ligands have been shown to enhance catalytic activity by mediating interactions between adsorbates and the active gold surfaces for specific oxygenation reactions.
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It is one of the most concentrated forms of coffee regularly consumed, with a distinctive flavor provided by crema, a layer of flavorful emulsified oils in the form of a colloidal foam floating on the surface, which is produced by the high pressure. Espresso is more viscous than other forms of brewed coffee. The moka pot, also known as the "Italian coffeepot" or the "caffettiera," is a three-chamber design which boils water in the lower section. The generated steam pressure, about one bar (100 kPa, 14.5 psi), forces the boiling water up through coffee grounds held in the middle section, separated by a filter mesh from the top section.
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A depletion force is an effective attractive force that arises between large colloidal particles that are suspended in a dilute solution of depletants, which are smaller solutes that are preferentially excluded from the vicinity of the large particles. One of the earliest reports of depletion forces that lead to particle coagulation is that of Bondy, who observed the separation or 'creaming' of rubber latex upon addition of polymer depletant molecules (sodium alginate) to solution. More generally, depletants can include polymers, micelles, osmolytes, ink, mud, or paint dispersed in a continuous phase. Depletion forces are often regarded as entropic forces, as was first explained by the established Asakura–Oosawa model.
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Copper-based "red goldstone" aventurine glass exists on a structural continuum with transparent red copper ruby glass and opaque "sealing wax" purpurin glass, all of which are striking glasses, the reddish colors of which are created by colloidal copper. The key variable is controlling the colloid size: goldstone has macroscopic reflective crystals; purpurin glass has microscopic opaque particles; copper ruby glass has submicroscopic transparent nanoparticles. The outer layers of a goldstone batch tend to have duller colors and a lower degree of glittery aventurescence. This can be caused by poor crystallization, which simultaneously decreases the size of reflective crystals and opacifies the surrounding glass with non reflective particles.
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The first catalysts for the dehydrogenation of ABs were derived from reduction of Rh(I) complexes to form the active colloidal heterogeneous catalyst. As in the case with the metal carbonyl catalysts, bulky secondary amine-boranes form monomeric aminoboranes. For RhL2\- and Rh(H)2L2-derived catalysts, the active species is a homogeneous catalyst, with the phosphine ligands interacting directly with the dehydrocoupling process. Changing the phosphine ligands from PiPr3 to PiBu3 significantly increases the turnover rate of the catalyst. Unlike other Rh(I) catalysts, the rhodium analogue of Wilkinson's catalyst RhCl(PHCy2)3 (Cy=cyclohexyl) behaves like the RhL2 and Rh(H)2L2 catalysts as a homogeneous species.
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The Noro–Frenkel law is particularly useful for the description of colloidal and globular protein solutions, for which the range of the potential is indeed significantly smaller than the particle size. For these systems the thermodynamic properties can be re-written as a function of only two parameters, the reduced density (using the effective diameter as length scale) and the reduced second-virial coefficient B. The gas-liquid critical point of all systems satisfying the extended law of corresponding states are characterized by same values of B at the critical point. The Noro-Frenkel law can be generalized to particles with limited valency (i.e. to non spherical interactions).
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The institute has a top-of-the-line Transmission Electron Microscope (TEM) (0.07 nm resolution), an additional TEM, Environmental Scanning Electron Microscope (ESEM) and advanced facilities for sample preparation including the Dual Focused Ion Beam. There is now also a new cryo TEM and a new high resolution cryo SEM. A UHV Scanning Tunneling Microscope (STM), Near Field Scanning Optical Microscope (NSOM), and Time of Flight Secondary Ion Mass Spectrometry (TOFSIMS) are now also available. Colloidal and molecular characterization equipment has been grouped under one roof and supplemented with small angle X-ray scattering and X-ray diffraction capabilities, as well as spectroscopy capabilities in solution.
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With Konrad Samwer he developed the Krausser-Samwer-Zaccone equation for the viscosity of liquids. With Eugene Terentjev he developed a molecular- level theory of the glass transition based on thermoelasticity, which provides the molecular-level derivation of the Flory-Fox equation for the glass transition temperature of polymers. He is also known for having developed, in his PhD thesis, the extension of DLVO theory that describes the stability of colloidal systems in fluid dynamic conditions based on a new solution (developed using the method of matched asymptotic expansions) to the Smoluchowski convection-diffusion equation. The predictions of the theory have been extensively verified experimentally by various research groups.
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Also in his PhD thesis, he developed a formula for the shear modulus of colloidal nanomaterials, which has been confirmed experimentally in great detail. In 2020 he discovered and mathematically predicted that the low-frequency shear modulus of confined liquids scales with inverse cubic power of the confinement size. In 2017 he was listed as one of the 37 most influential researchers worldwide (with less than 10-12 years of independent career) by the journal Industrial & Engineering Chemistry Research published by the American Chemical Society. In 2020 he was listed among the Emerging Leaders by the Journal of Physics published by the Institute of Physics.
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Geothermal power plants often bring brine to the surface as part of the operation. This brine is usually re-injected into the ground, but some experiments have been made to extract minerals before re-injection. Brine brought to the surface by geothermal energy plants has been used in pilot plants as a source of colloidal silica (Wairakei, New Zealand, and Mammoth Lakes, California), and as a source of zinc (Salton Sea, California).W. L. Bourcier, M. Lin, and G. Nix, Recovery of Minerals and Metals from Geothermal Fluids, Lawrence Livermore National Laboratory, 8 September 2005 Boron was recovered circa 1900 from geothermal steam at Larderello, Italy.
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Doped ZnS/ZnSe QDs, graphene QDs and silicon QDs are the novel Cd-free QDs (CFQDs) types that have been demonstrated their low-toxicity and high colloidal and PL stability for in vitro and in vivo models. DNA/peptide-functionalized QDs have been widely used for targeted cell and tissue imaging and the monitoring of the drug delivery path. For example, various techniques are used for the Cd-free QDs imaging including confocal/multiphoton microscopy, CARS imaging. Through these techniques with Cd-free QDs as stable fluorescent labels, researchers can observe the cell and tissue structure with higher resolutions and in a much more biocompatible way.
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Alprazolam regular release and orally disintegrating tablets are available as 0.25 mg, 0.5 mg, 1 mg, and 2 mg tablets, while extended release tablets are available as 0.5 mg, 1 mg, 2 mg, and 3 mg. Liquid alprazolam is available in a 1 mg/mL oral concentrate. Inactive ingredients in alprazolam tablets and solutions include microcrystalline cellulose, corn starch, docusate sodium, povidone, sodium starch glycollate, lactose monohydrate, magnesium stearate, colloidal silicon dioxide, and sodium benzoate. In addition, the 0.25 mg tablet contains D&C; Yellow No. 10 and the 0.5 mg tablet contains FD&C; Yellow No. 6 and D&C; Yellow No. 10.
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Gold alloys are used in restorative dentistry, especially in tooth restorations, such as crowns and permanent bridges. The gold alloys' slight malleability facilitates the creation of a superior molar mating surface with other teeth and produces results that are generally more satisfactory than those produced by the creation of porcelain crowns. The use of gold crowns in more prominent teeth such as incisors is favored in some cultures and discouraged in others. Colloidal gold preparations (suspensions of gold nanoparticles) in water are intensely red-colored, and can be made with tightly controlled particle sizes up to a few tens of nanometers across by reduction of gold chloride with citrate or ascorbate ions.
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Technologically, colloidal crystals have found application in the world of optics as photonic band gap (PBG) materials (or photonic crystals). Synthetic opals as well as inverse opal configurations are being formed either by natural sedimentation or applied forces, both achieving similar results: long-range ordered structures which provide a natural diffraction grating for lightwaves of wavelength comparable to the particle size. Novel PBG materials are being formed from opal-semiconductor-polymer composites, typically utilizing the ordered lattice to create an ordered array of holes (or pores) which is left behind after removal or decomposition of the original particles. Residual hollow honeycomb structures provide a relative index of refraction (ratio of matrix to air) sufficient for selective filters.
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Membrane developments have improved filtration at reduced operating pressures which has resulted in RO becoming an economical technology for soluble ion removal. Steam-Assisted Gravity Drainage (SAGD): Used in the oil sands SAGD brings together many products to provide easier, low-impact oil extraction with flows ranging from 50 to 5,000 m3/h (220 gpm to 22,000 gpm).SAGD PRODUCED & BRACKISH WATER TREATMENT Ultrafiltration Skids: Produces very low turbidity water used in industry, with membranes that have a pore size of 0.01 µm which can economically remove colloidal matter that would normally foul a microfiltration system. Vacuum Degassers: Used to remove oxygen, carbon- dioxide and nitrogen from water down to part-per-billion levels.
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Research, however, has failed to show that the chemical composition of the pink enamel pigment to be the same as that of the European one, although the cobalt blue of the enamel from some famille rose pieces has been determined to be from Europe. The oil used in gold-red Chinese enamel was doermendina oil instead of turpentine oil used in the West. Colloidal gold may have been previously available for use in Jingdezhen to achieve such colours, and gold-red enamel technique from Guangdong was used during the reign of Kangxi. Rudimentary famille rose have been found in Chinese porcelain from the 1720s, although the technique was not fully developed until around 1730 during the Yongzheng period.
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There has long been evidence that the cytoplasm behaves like a sol-gel. It is thought that the component molecules and structures of the cytoplasm behave at times like a disordered colloidal solution (sol) and at other times like an integrated network, forming a solid mass (gel). This theory thus proposes that the cytoplasm exists in distinct fluid and solid phases depending on the level of interaction between cytoplasmic components, which may explain the differential dynamics of different particles observed moving through the cytoplasm. A papers suggested that at length scale smaller than 100 nm, the cytoplasm acts like a liquid, while in a larger length scale, it acts like a gel.
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The process utilises identical molecules of a molecular cluster compound as the nucleation sites for nanoparticle growth, thus avoiding the need for a high temperature injection step. Particle growth is maintained by the periodic addition of precursors at moderate temperatures until the desired particle size is reached. The molecular seeding process is not limited to the production of cadmium-free quantum dots; for example, the process can be used to synthesise kilogram batches of high quality II-VI quantum dots in just a few hours. Another approach for the mass production of colloidal quantum dots can be seen in the transfer of the well-known hot-injection methodology for the synthesis to a technical continuous flow system.
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A Cyclic pump is an apparatus which moves a fluid in a periodic uni- directional direction from one containment system to another while overcoming static conditions that would, without intervention, not move. The intervention predicated by the pump alters pressures, volumes and sometimes temperatures of fluids (gaseous, liquid, colloidal, plasmic, etc.) in such a way that the fluids are transported to other chambers or enclosures (including pipes), thus "flowing" in a consistent direction, usually having characteristics of pulsation (as is the case with the Human heart) or of uniform motion (as is the case with an Automobile motor oil pump). Cyclic pumps are generally incorporated into machines to deal with all sorts of fluids associated with that machine's functionality.
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Sedimentation field flow fractionation (SFFF) is a non-destructive separation technique which can be used for both separation, and collecting fractions. Some applications of SFFF include characterization of particle size of latex materials for adhesives, coatings and paints, colloidal silica for binders, coatings and compounding agents, titanium oxide pigments for paints, paper and textiles, emulsion for soft drinks, and biological materials like viruses and liposomes. Some main aspects of SFFF include: it provides high- resolution possibilities for size distribution measurements with high precision, the resolution is dependent on experimental conditions, the typical analysis time is 1 to 2 hours, and it is a non-destructive technique which offers the possibility of collecting fraction.
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The fluorescence of colloidal semiconductors is another property analyzed in creating sensor systems. Quantum dots are semiconducting nanoparticles which are small enough to confine a generated hole-electron pair in all three spatial directions, leading to quantization of the energy levels causing the electronic structure of the material to sit between a classical semiconductor and a classic molecular material. This quantization causes nanoparticles to display sharp photon absorption and emission bands, and the band gap is closely related to the size of the nanoparticle. Fluorescence arises from photoexcitation in these quantum dots and is easily tuned to the visible or near infrared region of the spectrum, by choice of semiconductor material and particle size, making quantum-useful fluorophores.
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In the peripheral organs, the lymphatic system performs important immune functions and runs parallel to the blood circulatory system to provide a secondary circulation that transports excess interstitial fluid, proteins, and metabolic waste products from the systemic tissues back into the blood. The efficient removal of soluble proteins from the interstitial fluid is critical to the regulation of both colloidal osmotic pressure and homeostatic regulation of the fluid volume of the body. The importance of lymphatic flow is especially evident when the lymphatic system becomes obstructed. In lymphatic associated diseases, such as elephantiasis (where parasites occupying the lymphatic vessels block the flow of lymph), the impact of such an obstruction may be dramatic.
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Illustration of the scanner displacement D, cantilever deflection ξ, and lever signal S. The force mode used in the colloidal probe technique is illustrated in the figure on the left. The scanner is fabricated from piezoelectric crystals, which enable its positioning with a precision better than 0.1 nm. The scanner is lifted towards the probe and thereby one records the scanner displacement D. At the same time, the deflection of the cantilever ξ is monitored as well, typically with a comparable precision. One measures the deflection by focusing a light beam originating from a non-coherent laser diode to the back of the cantilever and detecting the reflected beam with a split photodiode.
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Philippe Guyot-Sionnest (born 1961, Nancy, France) is a professor at the University of Chicago appointed jointly in the departments of physics and chemistry.Experimental Condensed Matter Physics at UChicagoPhysical Chemistry at UChicago He works in the field of colloidal semiconductors and metal nanocrystals. He gained a Diplome d'Etude Approfondie in Orsay, France, in 1984 and a Ph.D at the University of California, Berkeley in 1987. He worked as a Research Scientist at the University of Paris-Sud in Orsay, France from 1988 to 1991, moving to the US in 1991 as Professor in both the Department of Chemistry and the Department of Physics at the University of Chicago, a position he has held since.
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Electrokinetic phenomena are a family of several different effects that occur in heterogeneous fluids, or in porous bodies filled with fluid, or in a fast flow over a flat surface. The term heterogeneous here means a fluid containing particles. Particles can be solid, liquid or gas bubbles with sizes on the scale of a micrometer or nanometer International Standard ISO 13099-1, 2012, "Colloidal systems – Methods for Zeta potential determination- Part 1: Electroacoustic and Electrokinetic phenomena"Dukhin, A. S. and Goetz, P. J. Characterization of liquids, nano- and micro- particulates and porous bodies using Ultrasound, Elsevier, 2017 . There is a common source of all these effects—the so-called interfacial 'double layer' of charges.
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The chromate coating process starts with a redox reaction between the hexavalent chromium and the metal. In the case of aluminum, for example, : + 0 → + These ions react with hydroxide ions in the water to form hydroxides : + 3 → : + 3 → Under appropriate conditions, these hydroxides will condense with elimination of water to form a colloidal sol of very small particles, that are deposited as a hydrogel on the metal's surface. The gel consists of a three-dimensional solid skeleton of oxides and hydroxides, with nanoscale elements and voids, enclosing a liquid phase. The structure of the gel depends on metal ion concentration, pH, and other ingredients of the solution, such as chelating agents and counterions.
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Between the main pit and Mina Sur there remains a substantial tonnage of so-called exotic copper in the channel of paleogravels (ancient gravels) between the two and which were mined in Mina Sur. The minerals, thought to be deposited by colloidal copper solutions leached from the main deposit, included manganese bearing copper pitch and copper wad, along with other impurities which made the ore difficult to leach in the original vats and produced a substandard cathode. The 'exotic' ore is now being heap leached and the copper extracted by SX/EW which leaves the impurities behind in the leach solution. It is expected that this operation will produce 129,000 tonnes of good quality copper cathode annually.
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The Roman philosopher Lucretius' scientific poem "On the Nature of Things" (c. 60 BC) has a remarkable description of Brownian motion of dust particles in verses 113–140 from Book II. He uses this as a proof of the existence of atoms: Reproduced from the book of Jean Baptiste Perrin, Les Atomes, three tracings of the motion of colloidal particles of radius 0.53 µm, as seen under the microscope, are displayed. Successive positions every 30 seconds are joined by straight line segments (the mesh size is 3.2 µm). Although the mingling motion of dust particles is caused largely by air currents, the glittering, tumbling motion of small dust particles is, indeed, caused chiefly by true Brownian dynamics.
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Lawless performed research on syphilis, leprosy, sporotrichosis, and other skin diseases. In 1936, he helped devise a new treatment for early stage syphilis (electropyrexia, which artificially raised a patient's temperature, and then injected the patient with therapeutic drugs). He also developed special treatments for skin damaged by arsenical preparations, which were commonly used during the 1920s against syphilis, and was one of the first doctors to use radium to treat cancer. Between 1921 and 1941 he published ten papers on dermatology, which including studies on warts, sporotrichosis, the use of colloidal mercuric sulphide, arsenicals, the treatment of early syphilis with electrically induced fever, tinea sycosis of the upper lip, tularemia, and congenital ichthyosiform erythroderma.
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Variable water flow can alter the sampling rates of metals by SLMDs, making a time-averaged concentration difficult to determine. By allowing liable metal analytes to diffuse to the SLMD's surface while limiting the diffusion of particulate, colloidal, or humic substances, these hydrophobic sheaths help reduce variability of SLMD uptake in faster moving waters. After being deployed for a known time interval, SLMDs can be recovered from the field for analysis. Washing with 20% nitric acid allows for the extraction of accumulated metals, and by using analytical techniques like inductively coupled plasma mass spectroscopy (ICP-MS) or atomic absorption spectroscopy (flame AAS) to measure the concentration of metal in the extract, the amount of metal accumulated by the SLMD can be determined.
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Contrary to the characteristics of other colloidal quantum dots such as CdSe, ABX3 QDs are shown to be bright, high quantum yield (above 80%) and stable emitters with narrow linewidths without surface passivation. In II-VI systems, the presence of dangling bonds on the surface results in photoluminescence quenching and photoluminescent intermittence or blinking. The lack of sensitivity to the surface can be rationalized from the electronic band structure and density of states calculations for these materials. Unlike conventional II-VI semiconductors where the band gap is formed by bonding and antibonding orbitals, the frontier orbitals in ABX3 QDs are formed by antibonding orbitals composed of Pb 6s 6p and X np orbitals (n is the principle quantum number for the corresponding halogen atom).
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It has been found to reduce the rate of invasive fungal infections and also reduce deaths when used in these babies. Liposomal nystatin is not commercially available, but investigational use has shown greater in vitro activity than colloidal formulations of amphotericin B, and demonstrated effectiveness against some amphotericin B-resistant forms of fungi. It offers an intriguing possibility for difficult-to-treat systemic infections, such as invasive aspergillosis, or infections that demonstrate resistance to amphotericin B. Cryptococcus is also sensitive to nystatin. Additionally, liposomal nystatin appears to cause fewer cases of and less severe nephrotoxicity than observed with amphotericin B. In the UK, its license for treating neonatal oral thrush is restricted to those over the age of one month.
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So the expansion process in a turbine can be easily calculated using the h–s chart when the process is considered to be ideal (which is the case normally when calculating enthalpies, entropies, etc. Later the deviations from the ideal values and they can be calculated considering the isentropic efficiency of the steam turbine used.) Lines of constant dryness fraction (x), sometimes called the quality, are drawn in the wet region and lines of constant temperature are drawn in the superheated region. X gives the fraction (by mass) of gaseous substance in the wet region, the remainder being colloidal liquid droplets. Above the heavy line, the temperature is above the boiling point, and the dry (superheated) substance is gas only.
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As limestone raises the pH of the bulk solution, and if heavy metals are present, precipitation of the metal hydroxides (with extremely low solubilities) is normally accelerated and the potential of armoring of limestone particles increases significantly. In the calcium silicate aggregate, as silicic acid species are absorbed onto the metal surface, the development of silica layers (mono- and bi-layers) lead to the formation of colloidal complexes with neutral or negative surface charges. These negatively charged colloids create an electrostatic repulsion with each other (as well as with the negatively charged calcium silicate granules) and the sequestered metal colloids are stabilized and remain in a dispersed state - effectively interrupting metal precipitation and reducing vulnerability of the material to armoring.
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Still another proposal, the "coagulation theory" states that the precipitate first forms as a fine colloidal dispersion, which then undergoes coagulation by an excess of the diffusing electrolyte and this somehow results in the formation of the rings. Some more recent theories invoke an auto-catalytic step in the reaction that results in the formation of the precipitate. This would seem to contradict the notion that auto-catalytic reactions are, actually, quite rare in nature. The solution of the diffusion equation with proper boundary conditions, and a set of good assumptions on supersaturation, adsorption, auto-catalysis, and coagulation alone, or in some combination, has not been done yet, it appears, at least in a way that makes a quantitative comparison with experiment possible.
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Due to the simple purification of this enzyme (5-30 fold purification is sufficient to reach homogeneity), its biological and biochemical analysis have been very thoroughly studied. In addition to the study of many isoforms within a given organism, there has been study dedicated to the understanding of HNL localization, the physical structure of the enzyme and its active site, and the mechanisms by which it is able to mediate this important set of reactions. Upon the purification of Black Cherry HNL, research from Wu and Poulton raised antiserum to these specific HNL, which were then applied (with colloidal gold particles in tow) to Black Cherry cotyledon and endosperm. Here it was found that HNL overwhelmingly localizes to the cell walls of these developing plants.
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Colloid vibration potential measures the AC potential difference generated between two identical relaxed electrodes, placed in the dispersion, if the latter is subjected to an ultrasonic field. When a sound wave travels through a colloidal suspension of particles whose density differs from that of the surrounding medium, inertial forces induced by the vibration of the suspension give rise to a motion of the charged particles relative to the liquid, causing an alternating electromotive force. The manifestations of this electromotive force may be measured, depending on the relation between the impedance of the suspension and that of the measuring instrument, either as colloid vibration potential or as colloid vibration current. Colloid vibration potential and current was first reported by Hermans and then independently by Rutgers in 1938.
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Oncotic pressure, or colloid osmotic pressure, is a form of osmotic pressure induced by proteins, notably albumin, in a blood vessel's plasma (blood/liquid) that displaces water molecules, thus creating a relative water molecule deficit with water molecules moving back into the circulatory system within the lower venous pressure end of capillaries. It has the opposing effect of both hydrostatic blood pressure pushing water and small molecules out of the blood into the interstitial spaces within the arterial end of capillaries and interstitial colloidal osmotic pressure. These interacting factors determine the partition balancing of total body extracellular water between the blood plasma and the larger extracellular water volume outside the blood stream. It has a major effect on the pressure across the glomerular filter.
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A selection of falangcai porcelains The origin of famille rose is not entirely clear. The pink colour palette was achieved in Europe through the use of purple of Cassius made of colloidal gold and first used on glass. It is generally believe that this use of the new colour palette in China was introduced by Jesuits in China to the Imperial court, initially on enamels used on metal wares such as cloisonné produced in the falang or enamel workshop (珐琅作), or through adaptation of enamels used in tin-glazed South German earthenware. The term used by Tang Ying (who oversaw the production of porcelain at Jingdezhen) and in Qing documents was yangcai ("foreign colours"), indicating its foreign origin or influence.
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"Trimethylene glycol dinitrate" or 1,3-propanediol dinitrate is isomeric with PGDN, and produced as a fractional byproduct in all but the most exacting laboratory conditions; the marginally lower specific gravity (and thus energy density) of this compound argues against its use, but the minor differences in chemistry may prove useful in the future. The related "dinitrodiglycol", more properly termed diethylene glycol dinitrate in modern notation, was widely used in World War 2 Germany, both alone as a liquid monopropellant and colloidal with nitrocellulose as a solid propellant. The otherwise desirable characteristics of this compound; it is quite stable, easy to manufacture, and has a very high energy density; are marred by a high freeze point (-11.5 deg. C) and pronounced thermal expansion, both being problematic in spacecraft.
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Bakker sold colloidal silver supplements, which he advertised as a panacea. In March 2020, the office of the Attorney General of New York ordered Bakker to cease making false medicinal claims about his supplements' alleged ability to cure the 2019-20 strains of coronavirus and the Federal Trade Commission and the Food and Drug Administration also sent a warning letter to Bakker about his claims regarding the supplements and coronavirus. Missouri attorney general Eric Schmitt and Arkansas attorney general Leslie Rutledge filed lawsuits against Bakker for allegedly pushing the supplements as a treatment for the virus. Bakker is represented by former Missouri governor Jay Nixon in his lawsuit against the state, who has argued for the suit to be dismissed.
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While SERS can be performed in colloidal solutions, today the most common method for performing SERS measurements is by depositing a liquid sample onto a silicon or glass surface with a nanostructured noble metal surface. While the first experiments were performed on electrochemically roughened silver, now surfaces are often prepared using a distribution of metal nanoparticles on the surface as well as using lithography or porous silicon as a support. Two dimensional silicon nanopillars decorated with silver have also been used to create SERS active substrates. The most common metals used for plasmonic surfaces are silver and gold; however, aluminium has recently been explored as an alternative plasmonic material, because its plasmon band is in the UV region, contrary to silver and gold.
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He soon realized that the commonly used extraction of lipids with petroleum ether had problems in that the extraction was not quantitative and the extract contained non-lipid contaminants. He then devised a procedure that involved precipitation of lipids and proteins with colloidal iron and removal of most of the non-lipid components with water, which solved the contamination problem.Short summary of Jordi Folch's achievements During these first investigations he co-signed a paper with Donald Van Slyke on an improved manometric method for carbon analysis. Using this newly developed method, he characterized the isolated "cephalin" fraction from brain tissue that after Johannes Thudichum (the nineteenth-century founder of the field of structural neurochemistry) was considered as pure phosphatidyl ethanolamine.
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In the face of Global Climate Change, he expanded the scope of his research to include the "Carbon sequestration in tropical soils". In his search to unravel inherent soil factors influencing erodibility (K) factor of erosion models, he published some pioneering works on soil colloidal- dispersion. He is author or co-author of many peer-reviewed articles in reputable Journals of Soil/Environmental Sciences. He is a NORAD Fellow; Fellow of Alexander von Humboldt (AvH) Germany; Regular Associate, International Centre for Theoretical Physics, Trieste, Italy; Fellow, Japanese Society for Promotion of Science; Winner, University of Nigeria Vice- Chancellor's Faculty and University Prizes 1992/93; Listed in Marquis Who's Who in Science and Engineering; and participant in German DAAD/DIES Deans Course 2009.
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He moved to UCLA as Associate Professor of Chemistry in 1975, and was promoted to full Professor in 1979 and to Distinguished Professor in 1999. He was Chair of the Department of Chemistry and Biochemistry at UCLA from 2000-2004 and has been a member of UCLA's California NanoSystems Institute since 2004 and of its Molecular Biology Institute from 2008. At UCLA he became a leader in the then-emerging fields of "complex fluids" and " soft matter physics". Shortly after moving there he began a 40-year collaboration with Avinoam Ben-Shaul on statistical- thermodynamic models of liquid crystal systems, polymer and polyelectrolyte (in particular, DNA) solutions, and colloidal suspensions, and on the self- assembly theory of micelles, surfactant monolayers, and biological membranes.
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A bandwidth well in excess of 1 GHz can be achieved with photodiode detectors. The main competitors of HgCdTe are less sensitive Si-based bolometers (see uncooled infrared camera), InSb and photon-counting superconducting tunnel junction (STJ) arrays. Quantum well infrared photodetectors (QWIP), manufactured from III-V semiconductor materials such as GaAs and AlGaAs, are another possible alternative, although their theoretical performance limits are inferior to HgCdTe arrays at comparable temperatures and they require the use of complicated reflection/diffraction gratings to overcome certain polarization exclusion effects which impact array responsivity. In the future, the primary competitor to HgCdTe detectors may emerge in the form of Quantum Dot Infrared Photodetectors (QDIP), based on either a colloidal or type-II superlattice structure.
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The whiteness of tofu is ultimately determined by the soybean variety, soybean protein composition and degree of aggregation of the tofu gel network. The yellowish beige color of soybeans is due to the color compounds including anthocyanin, isoflavones and polyphenol compounds; therefore the soybean variety used will predicate the color of the final tofu product. Ways to reduce the yellow color include reducing isoflavone content by changing the pH of the soy milk solution used in the production of the tofu so that the relevant compounds precipitate out and are removed during the extraction of okara. The opacity of tofu gel and the off- white color typical of standard uncooked firm tofu is due to the scattering of light by the colloidal particles of the tofu.
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Solid lipid nanoparticles (SLNs) are a new pharmaceutical delivery system or pharmaceutical formulation. The conventional approaches such as use of permeation enhancers, surface modification, prodrug synthesis, complex formation and colloidal lipid carrier based strategies have been developed for the delivery of drugs to intestinal lymphatics. In addition, polymeric nanoparticles, self-emulsifying delivery systems, liposomes, microemulsions, micellar solutions and recently solid lipid nanoparticles (SLN) have been exploited as probable possibilities as carriers for oral intestinal lymphatic delivery.Studies on binary lipid matrix based solid lipid nanoparticles of repaglinide: in vitro and in vivo evaluation. Rawat MK, Jain A and Singh S, Journal of Pharmaceutical Sciences, 2011, volume 100, issue 6, pages 2366-2378 A solid lipid nanoparticle is typically spherical with an average diameter between 10 and 1000 nanometers.
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The U.S. Food and Drug Administration recommends applying a wet compress or soaking the affected area in cool water; topical corticosteroids (available over-the- counter) or oral corticosteroids (available by prescription); and topical skin protectants, such as zinc acetate, zinc carbonate, zinc oxide, and calamine. Baking soda or colloidal oatmeal can relieve minor irritation and itching. Aluminium acetate, sometimes known as Burow's solution, can also ease the rash. Showers or compresses using hot (but not scalding) water can relieve itching for up to several hours, though this "also taxes the skin's integrity, opening pores and generally making it more vulnerable", and is only useful for secondary treatment (not for cleaning urushiol from the skin, which should be done with cold water).
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Oxymorphone is commercially produced from thebaine, which is a minor constituent of the opium poppy (Papaver somniferum) but thebaine is found in greater abundance (3%) in the roots of the oriental poppy (Papaver orientale). German patents from the mid-1930s indicate that oxymorphone as well as hydromorphone, hydrocodone, oxycodone, and acetylmorphone can be prepared—without the need for hydrogen gas—from solutions of codeine, morphine, and dionine by refluxing an acidic aqueous solution, or the precursor drug dissolved in ethanol, in the presence of certain metals, namely palladium and platinum in fine powder or colloidal form or platinum black. Oxymorphone hydrochloride occurs as odourless white crystals or white to off-white powder. It darkens in colour with prolonged exposure to light.
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The structural relaxation of a viscoelastic gel has been identified as primary mechanism responsible for densification and associated pore evolution in both colloidal and polymeric silica gels. Experiments in the viscoelastic properties of such skeletal networks on various time scales require a force varying with a period (or frequency) appropriate to the relaxation time of the phenomenon investigated, and inversely proportional to the distance over which such relaxation occurs. High frequencies associated with ultrasonic waves have been used extensively in the handling of polymer solutions, liquids and gels and the determination of their viscoelastic properties. Static measurements of the shear modulus have been made, as well as dynamic measurements of the speed of propagation of shear waves, which yields the dynamic modulus of rigidity.
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Working further on the Raman Effect, Krishnan discovered the reciprocity relations between the intensity of the horizontally polarised incident light getting scattered with horizontal polarization irrespective of the colloidal particles. This is known as Krishnan (reciprocity) Effect and the article was published in IISc journal on recommendation from C. V. Raman in 1936. He is credited with researches on Second Order Raman Spectra in diamond and in alkali halide crystals and is reported to have successfully recorded the phenomena for the first time, using the ultraviolet (mercury 2536 Å) technique of excitation for Raman spectroscopy, a technique he developed, on which he published a number of articles in peer reviewed journals. This is known to have provided conformation of Born's lattice dynamical theory.
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Schematic representation of the different stages and routes of the sol–gel technology In this chemical procedure, a "sol" (a colloidal solution) is formed that then gradually evolves towards the formation of a gel-like diphasic system containing both a liquid phase and solid phase whose morphologies range from discrete particles to continuous polymer networks. In the case of the colloid, the volume fraction of particles (or particle density) may be so low that a significant amount of fluid may need to be removed initially for the gel-like properties to be recognized. This can be accomplished in any number of ways. The simplest method is to allow time for sedimentation to occur, and then pour off the remaining liquid.
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For the 2002 São Paulo Biennial, Cruzvillegas wrote: "However art makes itself evident, it shall remain, above all, raw source material in all its natural, unstable, physical, chaotic and crystalline states: solid, liquid, colloidal and gaseous. It is the joy of energy." Frieze Magazine, Retrieved 1 April 2011 Reviewing Cruzvillegas' 2003 show for The New York Times, Holland Cotter wrote, "In all Mr. Cruzvillegas's work, little is stated but much is said". In a monograph on Cruzvillegas' work in Frieze magazine in 2006, Tom Morton discusses an untitled work from 1993 which recalls Marcel Duchamp's 1913 Bicycle Wheel, though the spokes have been replaced "by a circular panel on which his father, now an academic, once painted a bouquet of red carnations".
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Science fiction works after WWII were influenced by the beliefs behind Alfred Korzybski’s General Semantics. When Korzybski launched General Semantics as a self-improvement program, John W. Campbell Jr. promoted its belief system to many widely read science fiction authors and encouraged people to write about it in works of science fiction. This is in spite of the fact that General Semantics has nothing to do with linguistics. As such, science fiction works of this era often contradict actual psycholinguistic theories. For example, in The World of Null-A by A. E. van Vogt describes language as having the ability to physically alter the human brain in the sense that if a language portrays reality untruthfully, “brain damage (in the form of sub-microscopic colloidal lesions) results”.
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Prof. Aksay is a member of the U.S. National Academy of Engineering, NAE (2010),İlhan Aksay was elected in 2010 as a member of National Academy of Engineering in Chemical and Materials Engineering for advances in ceramics processing methods, biologically inspired materials processing, and field-induced layering of colloidal crystals. the Science Academy, Turkey (2012), and the U.S. National Academy of Inventors, NAI (2014). He is also a Fellow of the American Association for the Advancement of Science (AAAS), the American Ceramic Society, and an honorary member of the Materials Research Society - Japan. He received the Richard M. Fulrath (1987) and the Edward C. Henry (2000) Awards of the American Ceramic Society, the Charles M. A. Stine Award of the American Institute of Chemical Engineers (1997), and the Turkish National Medal of Science (Tübitak) (2001).
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Setting this work aside since 2002, his next paper on the subject was only in 2017 reporting magic sized InP and InAs clusters. Subsequent work on related clusters with the groups of Richard D. Robinson and Tobias Hanrath has finally lead to the discovery of the reversible isomerization of inorganic clusters – a discovery made by chance during the shipping of the samples. This work was called "the final bridge" between molecules and nanocrystals. One of the most recognized contribution of Banin to the field of colloidal nanostrucutres is the first demonstration of selective metal growth on semiconductor nanocrystals, resembling well-known bulk systems such as the Schottky diode, and the subsequent refinement of related synthesis procedures and the discovery of similar structures, as well as the physical characterization of such systems.
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William A. Albrecht (1888–1974)Springerlink, Obituary of William A. Albrecht, 1974 chairman of the Department of Soils at the University of Missouri, was the foremost authority on the relation of soil fertility to human health and earned four degrees from the University of Illinois at Urbana–Champaign. As emeritus professor of soils at the University of Missouri, he saw a direct link between soil quality, food quality and human health. He drew direct connections between poor quality forage crops, and ill health in livestock and from this developed a formula for ideal ratios of cations in the soil, the Base Cation Saturation Ratio. While he did not discover cation exchange in the soil as is sometimes supposed, he may have been the first to associate it with colloidal clay particles.
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The history of electrophoresis for molecular separation and chemical analysis began with the work of Arne Tiselius in 1931, while new separation processes and chemical analysis techniques based on electrophoresis continue to be developed in the 21st century. Tiselius, with support from the Rockefeller Foundation, developed the "Tiselius apparatus" for moving boundary electrophoresis, which was described in 1937 in the well-known paper "A New Apparatus for Electrophoretic Analysis of Colloidal Mixtures". The method spread slowly until the advent of effective zone electrophoresis methods in the 1940s and 1950s, which used filter paper or gels as supporting media. By the 1960s, increasingly sophisticated gel electrophoresis methods made it possible to separate biological molecules based on minute physical and chemical differences, helping to drive the rise of molecular biology.
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In materials science, segregation is the enrichment of atoms, ions, or molecules at a microscopic region in a materials system. While the terms segregation and adsorption are essentially synonymous, in practice, segregation is often used to describe the partitioning of molecular constituents to defects from solid solutions, whereas adsorption is generally used to describe such partitioning from liquids and gases to surfaces. The molecular-level segregation discussed in this article is distinct from other types of materials phenomena that are often called segregation, such as particle segregation in granular materials, and phase separation or precipitation, wherein molecules are segregated in to macroscopic regions of different compositions. Segregation has many practical consequences, ranging from the formation of soap bubbles, to microstructural engineering in materials science, to the stabilization of colloidal suspensions.
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Examples include transition-metal complexes such as tris(bipyridine)ruthenium(II) chloride, whose luminescence comes from an excited (nominally triplet) metal-to-ligand charge-transfer (MLCT) state, which is not a true triplet state in the strict sense of the definition; and colloidal quantum dots, whose emissive state does not have either a purely singlet or triplet spin. Most luminophores consist of conjugated π systems or transition-metal complexes. There are also purely inorganic luminophores, such as zinc sulfide doped with rare-earth metal ions, rare-earth metal oxysulfides doped with other rare-earth metal ions, yttrium oxide doped with rare-earth metal ions, zinc orthosilicate doped with manganese ions, etc. Luminophores can be observed in action in fluorescent lights, television screens, computer monitor screens, organic light-emitting diodes and bioluminescence.
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When one set of polyvalent DNA gold nanoparticles is combined with another that is functionalized with complementary DNA sequences, the particles assemble via DNA hybridization interactions. These nanoparticles can be used to prepare a wide range of colloidal crystals with sub-nanometer level precision (Fig. 2).Macfarlane, R. J.; Lee, B.; Jones, M. R.; Harris, N.; Schatz, G. C.; Mirkin, C. A. “Nanoparticle Superlattice Engineering with DNA,” Science, 2011, 334, 204-208. doi: 10.1126/science.1210493. Polyvalent DNA gold nanoparticles also form the basis for a new field of chemistry where a particle can be viewed as an “atom” and the DNA as “bonds” to make higher-order materials.Jones, M. R.; Seeman, N. C.; Mirkin, C. A. “Programmable Materials and the Nature of the DNA Bond,” Science, 2015, 347, 1260901, doi: 10.1126/science.1260901.
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This combination of fine pore size and the bactericidal properties of colloidal silver produce an effective filter, killing over 98 percent of the contaminants that cause diarrhea, thus dramatically reducing public health problems in the communities that use them to purify potable water. He designed a mold for the filter and a special clay press that was operated with a tire jack.Science Guardian The Family of the Americas Association, a Guatemalan organization, conducted a one-year follow-up study on the initial Mazariegos- developed filter project, concluding that this filter helped to reduce the incidence of diarrhea in participating households by as much as 50 percent. Laboratory testing and field studies have been performed on the filter by various institutions, including MIT, Tulane University, University of Colorado and University of North Carolina.
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The inability of the polymers to penetrate the colloids leads to a region around the colloids in which the polymer density is reduced. If the regions of reduced polymer density around two colloids overlap with one another, by means of the colloids approaching one another, the polymers in the system gain an additional free volume that is equal to the volume of the intersection of the reduced density regions. The additional free volume causes an increase in the entropy of the polymers, and drives them to form locally dense-packed aggregates. A similar effect occurs in sufficiently dense colloidal systems without polymers, where osmotic pressure also drives the local dense packing of colloids into a diverse array of structures that can be rationally designed by modifying the shape of the particles.
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Argyrol was never patented because Barnes planned to promote it exclusively through his trademark of Argyrol, as the colloidal silver protein for antiseptic use to mucous membranes. The original company was a partnership of Dr Albert C. Barnes, a physician, and Dr. Herman Hille, a chemist, who developed the process of manufacturing it at the urging of Barnes. By World War II, Argyrol post-exposure male hygiene was mandatory in the U.S. and Allied Military VD Prevention Technology for sexual hygiene. With the advent of antibiotics, prevention was out distanced by the promise of cure by simple injection. After that, Argyrol Anti-Infective was prescribed less often because Argyrol’s 10% Stabilized Solution was available without a prescription, while compounded solutions of mild silver protein, at any requested strength, were available by prescription.
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Although Argyrol is used as a synonym for the chemical descriptions silver vitelline and mild silver protein, Barnes insisted Argyrol was different. A silver-gelatin colloid, made by the reaction of silver nitrate, sodium hydroxide, and gelatin, in which a complex colloidal aggregate is formed, Barnes could rightfully assert Argyrol differed in its chemical assay, for instance, as it was claimed to contain over 30% silver. When compounded in varying strengths, nevertheless, Argyrol is silver protein identified as to its molecular construct. Argyrol is an over-the-counter internationally recognized anti-infection drug, regulatory-compliant immediate to manufacture and distribution in every jurisdiction for antiseptic use in medicine specifically due to global drug regulatory administrative adjudication initiated by the Food and Drug Administration in the United States to mandate New Drug Applications for silver drugs.
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Fluorescence intermittency, or blinking, is the phenomenon of random switching between ON (bright) and OFF (dark) states of the emitter under its continuous excitation. It is a common property of the nanoscale emitters (molecular fluorophores, colloidal quantum dots) related to the competition between the radiative and non-radiative relaxation pathways. The peculiar feature of such blinking in most cases is the power-law (in contrast to exponential) statistics of the ON and OFF time distributions, meaning that the measurements of the time-averaged intensity of a single emitter is not reproducible in different experiments and implying a complex dynamics of the involved process. In other words, in one experiment the emitter can blink frequently, while in another it may stay ON (or OFF) for almost entire length of the experiment (even for extremely long measurement times).
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Thus, it has been known for many years that, due to repulsive Coulombic interactions, electrically charged macromolecules in an aqueous environment can exhibit long-range crystal-like correlations with interparticle separation distances, often being considerably greater than the individual particle diameter. In all of these cases in nature, the same brilliant iridescence (or play of colors) can be attributed to the diffraction and constructive interference of visible lightwaves that satisfy Bragg’s law, in a matter analogous to the scattering of X-rays in crystalline solids. The large number of experiments exploring the physics and chemistry of these so- called "colloidal crystals" has emerged as a result of the relatively simple methods that have evolved in the last 20 years for preparing synthetic monodisperse colloids (both polymer and mineral) and, through various mechanisms, implementing and preserving their long-range order formation.
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Advances in confocal microscopy at the end of the 20th century identified proteins, RNA or carbohydrates localising to many non-membrane bound cellular compartments within the cytoplasm or nucleus which were variously referred to as 'puncta/dots', 'signalosomes', 'granules', 'bodies', 'assemblies', 'paraspeckles', 'purinosomes', 'inclusions', 'aggregates' or 'factories'. During this time period (1995-2008) the concept of phase separation was re-borrowed from colloidal chemistry & polymer physics and proposed to underlie both cytoplasmic and nuclear compartmentalization. Since 2009, further evidence for biomacromolecules undergoing intracellular phase transitions (phase separation) has been observed in many different contexts, both within cells and in reconstituted in vitro experiments. The newly coined term "biomolecular condensate" refers to biological polymers (as opposed to synthetic polymers) that undergo self assembly via clustering to increase the local concentration of the assembling components, and is analogous to the physical definition of condensation.
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Most chemists, since the discoveries of John Dalton in 1808, and James Clerk Maxwell in Scotland and Josiah Willard Gibbs in the United States, shared Boltzmann's belief in atoms and molecules, but much of the physics establishment did not share this belief until decades later. Boltzmann had a long-running dispute with the editor of the preeminent German physics journal of his day, who refused to let Boltzmann refer to atoms and molecules as anything other than convenient theoretical constructs. Only a couple of years after Boltzmann's death, Perrin's studies of colloidal suspensions (1908–1909), based on Einstein's theoretical studies of 1905, confirmed the values of Avogadro's number and Boltzmann's constant, convincing the world that the tiny particles really exist. To quote Planck, "The logarithmic connection between entropy and probability was first stated by L. Boltzmann in his kinetic theory of gases".
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Between 1984 and 1989 he worked at the Mathematical Institute at the University of Oxford, largely on both applications and modelling within physiology and biology. In 1989 he joined a commercial consulting company working in the environmental sciences, building up a mathematical modelling group on multidisciplinary projects in the UK, Europe, US and Japan. His research ranged from the application of fractals to simulating subsurface environments (micro medium structure controlling channelling flow and dispersion phenomena at the macroscopic scale), and non-linear multiphase (solutes, gases, and especially colloidal) dispersion processes, fully coupled chemical-temperature–hydration systems, through to the development of frameworks for estimating uncertainties within risk assessments, and the analysis of public risk perception. He has developed models and methods for analyzing large networks (range dependent random graphs) occurring within the biosciences, such as in genome, proteome and metabolome interactions.
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They tried to generate elemental rubidium by electrolysis of molten rubidium chloride, but instead of a metal, they obtained a blue homogeneous substance, which "neither under the naked eye nor under the microscope showed the slightest trace of metallic substance". They presumed that it was a subchloride (); however, the product was probably a colloidal mixture of the metal and rubidium chloride. In a second attempt to produce metallic rubidium, Bunsen was able to reduce rubidium by heating charred rubidium tartrate. Although the distilled rubidium was pyrophoric, they were able to determine the density and the melting point. The quality of this research in the 1860s can be appraised by the fact that their determined density differs by less than 0.1 g/cm3 and the melting point by less than 1 °C from the presently accepted values.
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Eraclius’ De Coloribus et Artibus includes instructions for creating green and red glass by adding copper (probably in the form of ore or copper filings) to the batch, a method practiced since ancient times. (The chapters on how to make red, green and blue glass are missing from De Divers Artibus.) As with the iron/manganese colours, the colours formed by the addition of copper oxide to the glass are dependent on the different oxidation states of the added copper. In an oxidising environment blue cupric (Cu2+) ions are formed, in a strongly reducing environment red colloidal cuprous (Cu1+) oxide is formed and if reoxidised then green cuprous (Cu1+) oxide results. The production of bright reds and blues in particular was straightforward, as the addition of copper to the mix resulted in the reliable creation of red, blue and green.
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The FFF method is unique to other separation techniques because it can separate materials over a wide colloidal size range while maintaining high resolution. Although FFF is an extremely versatile technique, there is no "one size fits all" method for all applications. In field-flow fractionation the field can be hydraulical (with an asymmetrical flow through a semi-permeable membrane), gravitational, centrifugal, thermal, electrical, or magnetic. In all cases, the separation mechanism is produced by differences in particle mobility (electrophoretic, when the field is a direct current (DC) electric field causing a transverse electric current flow) under the forces of the field, in equilibrium with the forces of diffusion: an often-parabolic laminar-flow-velocity profile in the channel determines the velocity of a particular particle, based on its equilibrium position from the wall of the channel.
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The three main structures phospholipids form in solution; the liposome (a closed bilayer), the micelle and the bilayer. In 1954 and 1958 Krishna Bahadur and co-workers published the successful synthesis of amino acids from a mixture of paraformaldehyde, colloidal molybdenum oxide or potassium nitrate and ferric chloride under sunlight. It appears that this experimental approach was seminal for the assays to produce Jeewanu, which he first reported in 1963 in an obscure Indian journal, Vijnana Parishad Anusandhan Patrika. His detailed syntheses were published in Germany in 1964 in a series of articles. Their initial experiment consisted of a sterilised apparatus in which inorganic nitrogenous compounds (such as ammonium phosphate and ammonium molybdate) and organic compounds such as citric acid (C6H8O7), paraformaldehyde (OH(CH2O)nH) and formaldehyde (CH2O) for carbon sources were mixed with minerals commonly found in living cells.
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Nobel Lecture: The Isolation and Properties of Crystalline TMV (1946) It has been known for many years that, due to repulsive Coulombic interactions, electrically charged macromolecules in an aqueous environment can exhibit long-range crystal-like correlations with interparticle separation distances often being considerably greater than the individual particle diameter. In all of the cases in nature, the same iridescence is caused by the diffraction and constructive interference of visible lightwaves which falls under Bragg’s law. Because of the rarity and pathological properties, neither opal nor any of the organic viruses have been very popular in scientific laboratories. The number of experiments exploring the physics and chemistry of these “colloidal crystals” has emerged as a result of the simple methods which have evolved in 20 years for preparing synthetic monodisperse colloids, both polymer and mineral, and, through various mechanisms, implementing and preserving their long-range order formation.
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Although this is a well-known process Electrodialysis is not commercially suited for seawater desalination, it can be used only for brackish water (TDS < 1000 ppm) and due to the complexity for modeling ion transport phenomena in the channels, the process perform could be affected considering the non-ideal behavior presented by the exchange membranes. The basic ED process could be modified and turn into RED, which operates in almost the same way of ED, except by the fact that the polarity of the electrodes changes periodically reversing the flow through the membranes. Due to that the deposition of colloidal substances is very difficult which makes this a self- cleaning process, almost eliminating the need for chemical pre-treatment, also making this type of treatment economically attractive process for brackish water. The use ED systems is not new, it has been used since 1954 and RED was developed in the '70s.
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In physics, condensation typically refers to a gas-liquid phase transition. In biology the term 'condensation' is used much more broadly and can also refer to liquid-liquid phase separation to form colloidal emulsions or liquid crystals within cells, and liquid-solid phase separation to form gels, sols, or suspensions within cells as well as liquid-to-solid phase transitions such as DNA condensation during prophase of the cell cycle or protein condensation of crystallins in cataracts. With this in mind, the term 'biomolecular condensates' was deliberately introduced to reflect this breadth (see below). Since biomolecular condensation generally involves oligomeric or polymeric interactions between an indefinite number of components, it is generally considered distinct from formation of smaller stoichiometric protein complexes with defined numbers of subunits, such as viral capsids or the proteasome - although both are examples of spontaneous molecular self-assembly or self- organisation.
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Clay chemistry is an applied subdiscipline of chemistry which studies the chemical structures, properties and reactions of or involving clays and clay minerals. It is a multidisciplinary field, involving concepts and knowledge from inorganic and structural chemistry, physical chemistry, materials chemistry, analytical chemistry, organic chemistry, mineralogy, geology and others. The study of the chemistry (and physics) of clays and clay minerals is of great academic and industrial relevance as they are among the most widely used industrial minerals, being employed as raw materials (ceramics, pottery, etc.), adsorbents, catalysts, additives, mineral charges, medicines, building materials and others. The unique properties of clay minerals including: nanometric scale layered construction, presence of fixed and interchangeable charges, possibility of adsorbing and hosting (intercalating) molecules, ability of forming stable colloidal dispersions, possibility of tailored surface and interlayer chemical modification and others, make the study of clay chemistry a very important and extremely varied field of research.
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The development of colleges and universities worldwide, most notably in the United States, would expand food chemistry as well with research of the dietary substances, most notably the Single-grain experiment during 1907-11. Additional research by Harvey W. Wiley at the United States Department of Agriculture during the late 19th century would play a key factor in the creation of the United States Food and Drug Administration in 1906. The American Chemical Society would establish their Agricultural and Food Chemistry Division in 1908 while the Institute of Food Technologists would establish their Food Chemistry Division in 1995. Food chemistry concepts are often drawn from rheology, theories of transport phenomena, physical and chemical thermodynamics, chemical bonds and interaction forces, quantum mechanics and reaction kinetics, biopolymer science, colloidal interactions, nucleation, glass transitions and freezing/disordered or noncrystalline solids, and thus has Food Physical Chemistry as a foundation area.
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In a colloidal dispersed system, ion dissolution arises, where the dispersed particles exist in equilibrium with their saturated counterpart, for example: :NaCl(s) Na+(aq) \+ Cl−(aq) The behavior of this system is characterised by the components activity coefficients and solubility product: :aNa+ · aCl− = Ksp In clay-aqueous systems the potential of the surface is determined by the activity of ions which react with the mineral surface. Frequently this is the hydrogen ion H+ in which case the important activity is determined by pH. The simultaneous adsorption of protons and hydroxyls as well as other potential determining cations and anions, leads to the concept of point of zero charge or PZC, where the total charge from the cations and anions at the surface is equal to zero. The charge must be zero, and this does not necessarily mean the number of cations versus anions in the solution are equal.
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This led to the field of Coherent control, quantum control through laser excitation, which was developed by other scientists at the University of Chicago. At the same time, he also began work on understanding the electrical properties of liquid metals, where the lack of translational orders frustrated attempts to understand their electronic band structure. The discrepancy between the dielectric results of reflectivity and ellipsometry data of liquid mercury led to work on the nature of conductivity at the liquid-vapor surface of liquid metal, ultimately showing that the existence of ion inhomogeneities at the interface led to electronic changes in the bulk liquid that persist for several atomic diameters into a liquid. Smaller research topics that Rice has published on included work on the chemistry of water, the theory of freezing liquids, the properties of monolayers on liquids, and confined colloidal systems, amongst others.
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Dispersion Technology Inc is a scientific instrument manufacturer located in Bedford Hills, New York. It was founded in 1996 by Philip Goetz (former Chairman, retired in 2010) and Dr. Andrei Dukhin (current CEO). The company develops and sells analytical instruments intended for characterizing concentrated dispersions and emulsions, complying with the International Standards for acoustic particle sizing ISO 20998 ISO 20998-1:2006 Measurement and characterization of particles by acoustic methods -- Part 1: Concepts and procedures in ultrasonic attenuation spectroscopyISO 20998-1:2013 Measurement and characterization of particles by acoustic methods -- Part 2: Guidelines for linear theory and Electroacoustic zeta potential measurement ISO 13099.ISO 13099-1:2012 Colloidal systems – Methods for zeta-potential determination – Part 1: Electroacoustic and electrokinetic phenomena Dispersion Technology manufactures a family of ultrasound based instruments for measuring particle size, zeta potential, high frequency rheology, and solid content in concentrated systems without diluting them.
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The solution spreads out uniformly, and the substrate is spun until the required thickness is achieved. Quantum dot based photovoltaic cells based on dye-sensitized colloidal TiO2 films were investigated in 1991 and were found to exhibit promising efficiency of converting incident light energy to electrical energy, and to be incredibly encouraging due to the low cost of materials used. A single-nanocrystal (channel) architecture in which an array of single particles between the electrodes, each separated by ~1 exciton diffusion length, was proposed to improve the device efficiency and research on this type of solar cell is being conducted by groups at Stanford, Berkeley and the University of Tokyo. Although research is still in its infancy, in the future nanocrystal photovoltaics may offer advantages such as flexibility (quantum dot-polymer composite photovoltaics ) lower costs, clean power generation and an efficiency of 65%,Quantum Dots May Boost Photovoltaic Efficiency To 65%, 24 May 2005 compared to around 20 to 25% for first-generation, crystalline silicon-based photovoltaics.
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Most of her scientific and research work was devoted to the study of non-biological, so-called colloidal, turbidity of beer and methods of delaying their production during storage. This work was followed by the introduction of optimal technological stabilization procedures in order to increase the physical-chemical stability of beer. In addition to the management of the institute (formerly the name of the department) at the ICT, she was for many years chair of the committee for state examinations and defense of diploma theses in the field of fermentation chemistry and bioengineering, chairman of the committees for defense of candidate (CSc.). She led the Commission of the Ministry of Education for the Defense and Appointment of Doctor of Technical Sciences in the field of Fermentation Chemistry and Technology (DrSc.), and became Vice-Chair of the Commission for the Defense of Doctorate of Technical Sciences (DrSc.) in the field of food chemistry and technology.
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His early work focused on instabilities and chaos in single and multimode lasers with particular emphasis in coherently driven instabilities associated with three-level systems. Lawandy's group was the first to observe optically encoded second-harmonic generation in bulk glasses and predicted the delocalization of carriers in disordered materials in strong light fields. In addition, Lawandy's research group developed novel laser fabrication methods for micro-optics in glasses, announced the first observations of the inhibition of spontaneous emission in a 3D photonic lattice of self-organized colloidal crystals and random media, Casimir forces in ordered dielectric media, laser action in a 3D FCC structure, and Random Laser action in scattering media with optically pumped dyes providing amplification of light. The work on random lasers [“laser Action in Strongly Scattering Media.” Nature 368, 436 (1994)] has resulted in a large body of work by many groups around the world and has been cited over 1400 times.
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Importantly, the discovery of high molecular weight macromolecular polymers cast doubt on the universality of colloidal phase separation in biology, despite the fact that individual polymers could still be observed to associate by clustering and phase separation to form colloids, liquid crystals, solid crystals or aggregates. A far greater impact occurred when Frederick Sanger determined the amino acid sequence of Insulin; ; ; . Sanger's Nobel lecture was also published in Science: and Linus Pauling, Robert Corey and Herman Branson correctly proposed the alpha helix and beta sheet as the primary structural motifs in protein secondary structure, while Max Perutz and John Kendrew analysed the 3D structure of myoglobin and later haemoglobin. These breakthroughs in protein structure determination led to a general focus of biologists on atomic-scale amino acid sequence- and 3D conformation-specific protein-protein interactions of a lock and key model type, usually between defined numbers of interacting subunits within a stoichiometric complex.
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Platinum nanoparticles are typically synthesized either by the reduction of platinum ion precursors in solution with a stabilizing or capping agent to form colloidal nanoparticles, or by the impregnation and reduction of platinum ion precursors in a micro-porous support such as alumina. Some common examples of platinum precursors include potassium hexachloroplatinate (K2PtCl6) or platinous chloride (PtCl2) Different combinations of precursors, such as ruthenium chloride (RuCl3) and chloroplatinic acid (H2PtCl6), have been used to synthesize mixed-metal nanoparticles Some common examples of reducing agents include hydrogen gas (H2), sodium borohydride (NaBH4) and ethylene glycol (C2H6O2), although other alcohols and plant-derived compounds have also been used. As the platinum metal precursor is reduced to neutral platinum metal (Pt0), the reaction mixture becomes supersaturated with platinum metal and the Pt0 begins to precipitate in the form of nanoscale particles. A capping agent or stabilizing agent such as sodium polyacrylic acid or sodium citrate is often used to stabilize the nanoparticle surfaces, and prevents the aggregation and coalescence of the nanoparticles.
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The slight pinkish tinge caused by colloidal scattering (the effect seen through a glass of water into which a couple of drops of milk have been mixed) is exacerbated, and the use of artificial light—especially fluorescent light—upsets the color rendition of a system which the Lumière Brothers carefully balanced for use with natural daylight. Making modern film or digital copies of Autochromes introduces other problems, because a color system based on red, green, and blue is used to copy an image that exists within the red-orange, green, and blue-violet system, providing further opportunities for color degradation. Vintage reproductions of Autochromes in old books and magazines have often been noticeably hand- adjusted by the photoengravers in an effort to compensate for some of the difficulties of reproduction, and as a result they sometimes look more like hand-colored photographs than "natural color" ones. In short, it is very difficult to form an accurate impression of the appearance of any Autochrome image without seeing the original "in person" and correctly illuminated.
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CTCs were observed for the first time in 1869 in the blood of a man with metastatic cancer by Thomas Ashworth, who postulated that "cells identical with those of the cancer itself being seen in the blood may tend to throw some light upon the mode of origin of multiple tumours existing in the same person". A thorough comparison of the morphology of the circulating cells to tumor cells from different lesions led Ashworth to conclude that "One thing is certain, that if they [CTC] came from an existing cancer structure, they must have passed through the greater part of the circulatory system to have arrived at the internal saphena vein of the sound leg". The importance of CTCs in modern cancer research began in the mid 1990s with the demonstration that CTCs exist early on in the course of the disease. Those results were made possible by exquisitely sensitive magnetic separation technology employing ferrofluids (colloidal magnetic nanoparticles) and high gradient magnetic separators invented by Paul Liberti and motivated by theoretical calculations by Liberti and Leon Terstappen that indicated very small tumors shedding cells at less than 1.0% per day should result in detectable cells in blood.
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