But Hexane isn't the only threat group targeting third-party companies.
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Hexane is a neurotoxin that can cause disorientation and have other neurological effects.
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The Federal Drug Administration allows Hexane to be present in food under certain conditions.
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Dragos said Hexane is expected to increase targeting oil and gas companies in the region.
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Hexane has "similar behaviors" to OilRig, a previously reported threat group with suspected Iranian ties.
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That operation contained more than a dozen 55-gallon drums of hexane, another volatile solvent.
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Other toxic gases — toluene, xylene, hexane and hydrogen sulfides — were also detected at higher-than-normal concentrations.
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Industrial security company Dragos, which discovered the group, calls it "Hexane," but remains largely tight-lipped on its activities.
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What consumers expect when they buy "natural" foods probably doesn't include additives like yellow dye #5, aspartame, or hexane.
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When the team rinsed flies in hexane, dissolving that layer, they lost their ability to stay dry in Mono's water.
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Hexane was first observed in mid-2018, said the company, which specializes in finding and understanding the threats faced by critical infrastructure.
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It is usually composed of propane, butane, pentane or hexane but can also contain carbon dioxide, hydrogen sulfide, aromatics and naphthenes, known as impurities.
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Many commonly used solvents, like chloroform, acetone and hexane, are harmful and volatile, posing risks to people who inhale them as well as the environment.
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Breanne Kincaid, the center's research director, told CNBC's "Fast Money" Thursday that some plant-based meat products are exposed to a chemical called Hexane when it is being processed.
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Dragos said Hexane, the latest in a list of nine hacking groups it tracks, was observed targeting telecoms companies, potentially as a "stepping stone" to gain access to the networks of oil and gas companies.
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Michael Jerrett, chair of the environmental health sciences department at the University of California, Los Angeles, conducted several studies in March 2015, after the leak was fixed, and found the toxic chemical compounds hexane and benzene inside two Porter Ranch homes.
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The researchers have "moderate confidence" that Hexane does not yet have an attack capability to disrupt industrial control networks critical to the continued operations of power plants, energy suppliers and other critical infrastructure, but the group may use its leverage on telecommunications networks as a "precursor" to an attack on industrial control networks.
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Afterwards a secondary coating layer of polyvinylidene fluoride (PVDF) is applied onto the coated water droplet. The doubly-coated water droplet is then cast into the hexane/water mixture and eventually settled at the hexane/water interface to form the interfacial water marble. During this process, the PVDF coating quickly diffused into hexane to balance the hydrophobic interaction between hexane and the water droplet, while the nanomaterials quickly self-assembled into a nanostructured protective layer on the droplet surface through the Marangoni effect. The interfacial water marble can completely resist coalescence cascade and exist nearly permanently at the hexane/water interface, providing that the hexane phase is not depleted by vaporization.
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There are several variations in the formulation. Sometimes 60% of the lanolin was replaced by neatsfoot oil. One disadvantage of the solvent hexane is its tendency to evaporate rapidly. Before the fat/hexane mixture has been able to penetrate deep into the leather the hexane evaporates to the surface of the leather, taking most fat with it.
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In May 2010 it emerged that employees in China producing touchscreens for the iPhone had been poisoned by a cleaning chemical called n-hexane, leading to nerve damage and in some cases paralysis.Chinese workers link sickness to n-hexane and Apple iPhone screens, Guardian n-Hexane was introduced into the production process because it evaporates very quickly, thus speeding the manufacturing. A hospital in Suzhou has treated more than 100 workers who breathed in the hexane vapours. Some workers have been hospitalized for more than six months.
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These results suggest that some components in petroleum benzine are likely to antagonize the neurotoxic effects of n-hexane to the peripheral nerves, possibly by inhibiting the oxidation of n-hexane to its more toxic metabolites 2-hexanone and 2,5-hexanedione. Ono and coworkers also observed depressed body weight gains amongst the exposed groups compared to the control group in the order: petroleum benzine II > petroleum benzine I (containing 200 ppm n-hexane) >> 500 ppm n-hexane > 200 ppm n-hexane. These results suggest that other components found in petroleum benzine may have an additive, syngeristic or potentiative effects on the biological effects of n-hexane.Takeuchi Y, Mabuchi C, Takagi S ( 1975) Polyneuropathy caused by petroleum benzine.
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Like most alkanes, hexane characteristically exhibits low reactivity and are suitable solvents for reactive compounds. Commercial samples of n-hexane however often contains methylcyclopentane, which features tertiary C-H bonds, which are incompatible with some radical reactions.
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2,5-Dimethylfuran plays a role in the mechanism for the neurotoxicity of hexane in humans. Together with hexane-2,5-dione and 4,5-dihydroxy-2-hexanone, it is one of the main metabolites of hexane.Peter Arlien-Søborg. Solvent Neurotoxicity.
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However, for n-hexane, the current NIOSH REL is 50 ppm () over an 8-hour workday. This limit was proposed as a permissible exposure limit (PEL) by the Occupational Safety and Health Administration in 1989; however, this PEL was overruled in US courts in 1992. The current n-hexane PEL in the US is 500 ppm (). Hexane and other volatile hydrocarbons (petroleum ether) present an aspiration risk.
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They are caused by the temporary repulsion of electrons away from the electrons of a neighboring molecule, leading to a partially positive dipole on one molecule and a partially negative dipole on another molecule. Hexane is a good example of a molecule with no polarity or highly electronegative atoms, yet is a liquid at room temperature due mainly to London dispersion forces. In this example, when one hexane molecule approaches another, a temporary, weak partially negative dipole on the incoming hexane can polarize the electron cloud of another, causing a partially positive dipole on that hexane molecule.In absence of solvents hydrocarbons such as hexane form crystals due to dispersive forces ; the sublimation heat of crystals is a measure of the dispersive interaction.
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The chronic toxicity of hexane is attributed to hexane-2,5-dione. The symptoms are tingling and cramps in the arms and legs, followed by general muscular weakness. In severe cases, atrophy of the skeletal muscles is observed, along with a loss of coordination and vision problems.Couri D, Milks M. "Toxicity and metabolism of the neurotoxic hexacarbons n-hexane, 2-hexanone, and 2,5-hexanedione" Annu. Rev. Pharmacol. Toxicol. 1982;22:145-66.
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The acute toxicity of hexane is rather low. Inhalation of n-hexane at 5000 ppm for 10 minutes produces marked vertigo; 2500-1000 ppm for 12 hours produces drowsiness, fatigue, loss of appetite, and paresthesia in the distal extremities; 2500–5000 ppm produces muscle weakness, cold pulsation in the extremities, blurred vision, headache and anorexia. Chronic occupational exposure to elevated levels of n-hexane has been demonstrated to be associated with peripheral neuropathy in auto mechanics in the US, and neurotoxicity in workers in printing presses, and shoe and furniture factories in Asia, Europe, and North America. The US National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) for hexane isomers (not n-hexane) of 100 ppm () over an 8-hour workday.
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PEG 400 is strongly hydrophilic. The partition coefficient of PEG 400 between hexane and water is 0.000015 (logP = -4.8), indicating that when PEG 400 is mixed with water and hexane, there are only 15 parts of PEG400 in the hexane layer per 1 million parts of PEG 400 in the water layer. PEG 400 is soluble in water, acetone, alcohols, benzene, glycerin, glycols, and aromatic hydrocarbons, and is slightly soluble in aliphatic hydrocarbons.
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Sake kasu can be beneficial for cosmetic use due to the high amount of triacylglycerols found in freeze-dried sake kazu. Tyrosinase catalytic activity is hindered by the n-hexane extract from freeze-dried sake kasu. Tyrosinase inhibitor was further purified by the n-hexane extract from the freeze-dried sake kasu. This process then causes the n-hexane extract to create a mixture of triacylglycerols, with the property of tyrosinase inhibition.
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3-Hexanol can be synthesized by the hydroboration of unsaturated hexane compounds such as 3-hexyne.
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Use of ozone depleting substances in laboratories. The Nordic Council (2003). Since hexane cannot be easily deprotonated, it is used in the laboratory for reactions that involve very strong bases, such as the preparation of organolithiums. For example, butyllithiums are typically supplied as a hexane solution.
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New York: Interscience Publisher 1962ACGIH: Documentation of the threshold limit values for substances in workroom air, pp.121, 124, 126, 191 and 200 (1971)Browning, E.: Toxicity and metabolism of industrial solvents, pp.145-171. London: Elsevier 1965 Many of the cases of polyneuropathy amongst workers chronically exposed to vapors of petroleum benzine and similar solvents have been attributed to the n-hexane component of these mixtures. Using an animal model (Wistar-strain male rats), Ono and coworkers reported that chronic exposure (12 h a day for 24 weeks) to hydrocarbon solvent vapors conspicuously impaired peripheral nerve function in the 500 ppm n-hexane group, slightly impaired in the 200 ppm n-hexane group and petroleum benzine II group (containing 500 ppm n-hexane), and barely impaired in the petroleum benzine I group (containing 200 ppm n-hexane).
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Hexane is a complete game engine developed by Slant Six Games for console, PC and mobile games.
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Highly refined peanut oil can contain traces of hexane, a petroleum byproduct used to maximize separation of oil from the solids of peanuts. The EPA identifies hexane as a neurotoxin in rat studies.Peanut Oil Extraction - Agico Group Official WebsiteHexane = EPA Report 09.2016 There are no specific regulations on the limits of hexane use in cooking oils. If quality control is neglected, peanuts that contain the mold that produces highly toxic aflatoxin can end up contaminating the oil derived from them.
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The first step was to triturate a sample of chocolate three times with n-hexane to remove fats.
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Although many PID manufacturers provide the ability to program an instrument with a correction factor for quantitative detection of a specific chemical, the broad selectivity of the PID means that the user must know the identity of the gas or vapor species to be measured with high certainty. If a correction factor for benzene is entered into the instrument, but hexane vapor is measured instead, the lower relative detector response (higher correction factor) for hexane would lead to underestimation of the actual airborne concentration of hexane.
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PCR amplified products are then validated by transfection into yeast cells and a Western blot protein identification. Problems arising from cell culture applications using DMF include protein adsorption to the device floor, and cytotoxicity to cells. To prevent adsorption of protein to the platform's floor, a surfactant stabilized Silicon oil or hexane was used to coat the surface of the device, and droplets were manipulated atop of the oil or hexane. Hexane was later rapidly evaporated from cultures to prevent a toxic effect on cell cultures.
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Hexane () is a straight-chain alkane with six carbon atoms and has the molecular formula C6H14. Hexane is a significant constituent of gasoline. It is a colorless liquid, odorless when pure, and with boiling points approximately . It is widely used as a cheap, relatively safe, largely unreactive, and easily evaporated non-polar solvent.
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The rare earth element Neodymium is extracted by di(2-ethyl-hexyl)phosphoric acid into hexane by an ion exchange mechanism.
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For example, hexane has a molecular formula of , or structurally , implying that it has a chain structure of 6 carbon atoms, and 14 hydrogen atoms. However, the empirical formula for hexane is . Likewise the empirical formula for hydrogen peroxide, , is simply HO expressing the 1:1 ratio of component elements. Formaldehyde and acetic acid have the same empirical formula, .
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The production of pure DVTOSU as a solid requires repeated recrystallization from hydrocarbons such as pentane or n-hexane or aqueous methanol.
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The term hexanes refers to a mixture, composed largely (>60%) of hexane, with varying amounts of the isomeric compounds 2-methylpentane and 3-methylpentane, and, possibly, smaller amounts of nonisomeric C5, C6, and C7 (cyclo)alkanes. Hexanes is cheaper than hexane and is often used in large scale operations not requiring a single isomer (e.g., as cleaning solvent or for chromatography).
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2,5-Hexanedione (Acetonylacetone) is an aliphatic diketone. It is a colorless liquid. In humans, it is a toxic metabolite of hexane and of 2-hexanone.
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The skeletal formula of hexane, with carbons number one and three labelled The 3d ball representation of hexane, with carbon (black) and hydrogen (white) shown explicitly. NOTE: It doesn't matter which end of the chain you start numbering from, as long as you're consistent when drawing diagrams. The condensed formula or the IUPAC name will confirm the orientation. Some molecules will become familiar regardless of the orientation.
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The Isochrysis galbana extract is said to have certain cosmetic and hair-growth properties when using hexane, ethyl acetate, ethanol, water, methanol, or isopropanol as extractants.
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2,3-Dimethylbutane is an isomer of hexane. It has the chemical formula (CH3)2CHCH(CH3)2. It is a colorless liquid which boils at 57.9 °C.
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PDF fulltext The resin is used as a treatment for gout, while the leaves are brewed into a medicinal tea. Hexane extracts of the leaves have been shown to possess anti- inflammatory properties in animal tests.Carretero M, López-Pérez J, Abad M, Bermejo P, Tillet S, Israel A, Noguera-P B. 2008. Preliminary study of the anti-inflammatory activity of hexane extract and fractions from Bursera simaruba(Linneo) Sarg.
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Secoisolariciresinol diglucoside can be isolated from de-fatted (hexane extraction) flaxseed by extraction of the lignan polymer precursor with a water/acetone mixture, followed by acetone removal and alkaline hydrolysis.
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Biogasoline is gasoline produced from biomass. Like traditionally produced gasoline, it contains between 6 (hexane) and 12 (dodecane) carbon atoms per molecule and can be used in internal-combustion engines.
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Solimonas variicoloris is a Gram-negative, rod-shaped and non-spore-forming bacterium from the genus of Solimonas which has been isolated from a hexane degrading biofilter from Hamm in Germany.
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To extract the oil, the seed is flaked, steamed and pressed. Residual oil in the cake can be extracted with hexane; alternatively all the oil can be extracted directly with the solvent.
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The anhydride has CAS number . Chlorendic acid is slightly soluble in water and nonpolar organic solvents (e.g. benzene, hexane, carbon tetrachloride). It is easily soluble in slightly polar organic solvents (ethanol, methanol, acetone).
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Alkanibacter is a Gram-negative genus of bacteria from the family of Sinobacteraceae with one known species (Fontimonas thermophila). Alkanibacter difficilis has been isolated from a hexane degrading biofilter in Hamm in Germany.
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Introduction of hexane into water causes disruption of the hydrogen bonding network between water molecules. The hydrogen bonds are partially reconstructed by building a water "cage" around the hexane molecule, similar to that in clathrate hydrates formed at lower temperatures. The mobility of water molecules in the "cage" (or solvation shell) is strongly restricted. This leads to significant losses in translational and rotational entropy of water molecules and makes the process unfavorable in terms of free energy of the system.
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It is prepared by reaction of nitrogen dioxide with cyclohexane. Cyclohexane is a convenient substrate because all twelve C-H bonds are equivalent, so mononitration does not give isomers (unlike the case of n-hexane).
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Almost all corn oil is expeller-pressed, then solvent-extracted using hexane or 2-methylpentane (isohexane).Corn Refiners Association. Corn Oil 5th Edition. 2006 The solvent is evaporated from the corn oil, recovered, and re-used.
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Guanacastepene A is a compound showing antibiotic activity. It is a diterpene that was extracted with hexane from a Costa Rican fungus, CR115, found on the branches of the Daphnopsis americana tree and purified by chromatography.
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Fresh plant material is extracted with nonpolar solvents (e. g., benzene, toluene, hexane, petroleum ether). On evaporation of the solvent, a semi-solid residue of essential oils, waxes, resins and other lipophilic (oil- soluble) plant chemicals remains.
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Karavilagenin E is a chemical compound found in the Balsam apple vine (Momordica balsamina). It is a cucurbitane-type triterpenoid, related to cucurbitacin. Karavilagenin E is soluble in methanol and ethyl acetate but insoluble in n-hexane.
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Triethylborane (TEB), also called triethylboron, is an organoborane (a compound with a B-C bond). It is a colorless pyrophoric liquid. Its chemical formula is (C2H5)3B, abbreviated Et3B. It is soluble in organic solvents tetrahydrofuran and hexane.
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For linear alkanes, molecular ion peaks are often observed. However, for long chain compounds, the intensity of the molecular ion peaks are often weak. Linear fragments often differ by 14 Da (CH2 = 14). For example, hexane fragmentation patterns.
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2-Methylpentane, trivially known as isohexane, is a branched-chain alkane with the molecular formula C6H14. It is a structural isomer of hexane composed of a methyl group bonded to the second carbon atom in a pentane chain.
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The company imports industrial chemical stock including caustic soda, potassium carbonate, normal hexane, chromic anhydride, zinc dusting powder, titanium white, other pigments, glycerine, seamless steel pipes, high alumina cement, nickel, silver, and various ingredients for the production of plastic.
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Vanadyl nitrate can form a solid pale yellow adduct with boron trifluoride. An adduct is also formed with acetonitrile. When mixed with petrol or l-hexene, or other unsaturated hydrocarbons, vanadyl nitrate ignites. It does not ignite with hexane.
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2015; Singh, et al. 2020a), two phytoecdysteroids, and one trihydrylated fatty acids (Rahman et al. 2017). Apart from that approximately, 24 steroidal saponins in parent extract (Singh et al. 2020b) and nine hydrophilic compounds in n-Hexane fraction (Khan et al.
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Fucitol, also known as L-fucitol, 6-deoxy-L-galactitol, and (2R,3S,4R,5S)-hexane-1,2,3,4,5-pentol, is a sugar alcohol derived from fucoidan which is found in the North Atlantic seaweed Fucus vesiculosus or by the reduction of fucose.
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For example, in the image below, the skeletal formula of hexane is shown. The carbon atom labeled C1 appears to have only one bond, so there must also be three hydrogens bonded to it, in order to make its total number of bonds four. The carbon atom labelled C3 has two bonds to other carbons and is therefore bonded to two hydrogen atoms as well. A ball-and-stick model of the actual molecular structure of hexane, as determined by X-ray crystallography, is shown for comparison, in which carbon atoms are depicted as black balls and hydrogen atoms as white ones.
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Until recently, Liu et al. has filled this void by proposing a new method to control coalescence cascade by using nanostructured coating at the liquid-liquid interface, —the interfacial liquid marbles. Figure 2. An interfacial water marble sitting on the hexane-water interface.
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A common choice of chemical solvent is hexane, which is widely used in the food industry and is relatively inexpensive. Benzene and ether can also separate oil. Benzene is classified as a carcinogen. Another method of chemical solvent extraction is Soxhlet extraction.
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2,5-Dimethylthiophene is an organosulfur compound with the formula C4H2(CH3)2S. It is one of four isomers of dimethylthiophene. A colorless liquid, it is prepared by sulfurization of hexane-2,5-dione. It is approved as a food flavouring additive in Europe.
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First, plant material is extracted with a hydrocarbon solvent, such as hexane, to yield a concrete. The concrete is then extracted with ethanol. The ethanol extract is cooled (e.g., to −15 °C) to solidify waxes, and cold filtered to yield a liquid extract.
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TOPO-coated quantum dots are typically soluble in chloroform, toluene, and (to a lesser extent) hexane. These quantum dots are also used in biological applications as part of the protective barrier to prevent degradation as it travels through the harsh climate of the body.
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Hexylamine or n-hexylamine is a chemical compound with the formula CH3CH2CH2CH2CH2CH2NH2. This colorless liquid is one of the isomeric amines of hexane. At standard temperature and pressure, it has the ammonia/bleach odor common to amines and is soluble in almost all organic solvents.
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Carbosulfan is an organic compound adherent to the carbamate class. At normal conditions, it is brown viscous liquid. It is not very stable; it decomposes slowly at room temperature. Its solubility in water is low but it is miscible with xylene, hexane, chloroform, dichloromethane, methanol and acetone.
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Sunflower oil can be extracted using chemical solvents (e.g., hexane), or expeller pressing (i.e., squeezed directly from sunflower seeds by crushing them). "Cold-pressing" (or expeller pressing) sunflower seeds under low-temperature conditions is a method that does not use chemical solvents to derive sunflower seed oil.
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As a base, hexyllithium generates n-hexane as a byproduct rather than gaseous butane, which results from the use of BuLi. Another advantage for HxLi is that it is slightly less reactive.Terry L. Rathman "Hexyllithium" Encyclopedia of Reagents for Organic Synthesis, 2001. Both of these aspects encourage industrial applications.
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Diethylaluminum cyanide was originally generated by treatment of triethylaluminum with a slight excess of hydrogen cyanide. The product is typically stored in ampoules because it is highly toxic. It dissolves in toluene, benzene, hexane and isopropyl ether. It undergoes hydrolysis readily and is not compatible with protic solvents.
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Butanol, with a four-carbon chain, is moderately soluble. Because of hydrogen bonding, alcohols tend to have higher boiling points than comparable hydrocarbons and ethers. The boiling point of the alcohol ethanol is 78.29 °C, compared to 69 °C for the hydrocarbon hexane, and 34.6 °C for diethyl ether.
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Similar to liquid marbles at the solid-air interface, the interfacial liquid marbles are constructed on the hexane/water interface using water droplets with a surface coating composed of nanoscale materials with special wettability (Figure 2). To realize interfacial water marbles at hexane/water interface, the individual particle size of the surface coating layer should be as small as possible, so that the contact line between the particles and the water reservoir can be minimized; special wettability with mixed hydrophobicity and hydrophilicity is also preferred for the interfacial water marble formation. The interfacial water marble can be fabricated by firstly coating a water droplet with nanomaterials with special wettability, e.g. hybrid carbon nanowires, graphene oxide.
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Three terpenoids and a tocopherol- related compound have been found in the aerial parts of Ricinus. Compounds named (3E,7Z,11E)-19-hydroxycasba-3,7,11-trien-5-one, 6α-hydroxy-10β-methoxy-7α,8α-epoxy-5-oxocasbane-20,10-olide, 15α-hydroxylup-20(29)-en-3-one, and (2R,4aR,8aR)-3,4,4a,8a-tetrahydro-4a-hydroxy-2,6,7,8a-tetramethyl-2-(4,8, 12-trimethyltridecyl)-2H-chromene-5,8-dione were isolated from the methanol extracts of Ricinus communis by chromatographic methods. Partitioned h-hexane fraction of Ricinus root methanol extract resulted in enrichment of two triterpenes: lupeol and urs-6-ene-3,16-dione (erandone). Crude methanolic extract, enriched n-hexane fraction and isolates at doses 100 mg/kg p.o.
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Although strigolactones vary in some of their functional groups, their melting point is usually found always between 200 and 202 Celsius degrees. The decomposition of the molecule occurs after reaching 195 °C. They are highly soluble in polar solvents, such as acetone; soluble in benzene, and almost insoluble in hexane.
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Water-based coatings began development in the late 1980s. In the early 1990s they began to be widely used, specifically marketed towards drinking water supply lines. Previously, water supply lines were coated using a harmful solvent-based coating, using such solvents as benzene, toluene, hexane and other volatile organic compounds (VOC).
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It is soluble in nonpolar solvents such as benzene, CH2Cl2, and hexane. In some aspects, the chemical properties of VOCl3 and POCl3 are similar. One distinction is that VOCl3 is a strong oxidizing agent, whereas the phosphorus compound is not. Neat VOCl3 is the usual chemical shift standard for 51V NMR spectroscopy.
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For some time, it has been known that hexane can perform this function. However, an electrical method may be cleaner and better overall. Electric fields have been applied in short pulses to extract hydrocarbons from other species of microalgae by weakening the cell walls. These pulses have been microseconds to milliseconds in length.
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Rabeprazole is characterized as a white to yellowish-white solid in its pure form. It is soluble in a number of solvents. Rabeprazole is very soluble in water and methanol, freely soluble in ethanol, chloroform, and ethyl acetate, and is insoluble in ether and n-hexane. It is unstable under humid conditions.
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A change of reaction medium from hexane to water increases the rate of t-BuCl heterolysis by 14 orders of magnitude.Dvorko, G. F., Ponomareva, E. A. and Ponomarev, M. E. (2004), Role of nucleophilic solvation and the mechanism of covalent bond heterolysis. J. Phys. Org. Chem., 17: 825–836. doi:10.1002/poc.
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Overhauser magnetometer provides extremely accurate measurements of the strength of the magnetic field. The Orsted (satellite) uses this type of magnetometer to map the magnetic fields over the surface of the earth. On the Vanguard 3 mission (1959) a proton processional magnetometer was used to measure geomagnetic fields. The proton source was hexane.
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Solubility in water is about 0.002 g/100 mL. It is slightly soluble in hexane and progressively more so in benzene, acetonitrile, methylene chloride, methanol, ethanol, and acetone. It is also soluble in aqueous alkali. The naturally occurring isomer trans-zearalenone (trans-ZEN) is transformed by ultraviolet irradiation to cis-zearalenone (cis-ZEN).
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Triptan structures were designed from the structure of 5-HT to attain affinity to 5-HT receptors, hence the identical indole structure. The hydroxyl group (-OH) on the hexane of the indole core and the alkyl-amine side chain on position C3 on 5-HT have been replaced with other compounds, such as sulfonamides or azol-ring structured derivatives and different amine-alkyl side chains. An electro-negative group can form a hydrogen bond with Thr in the pocket of the receptor. Sulfonamide derivatives attached to the hexane ring of the indole structure have electro-negative properties, as well as the triazole and 2-oxazolidone on rizatriptan and zolmitriptan respectively. This can increase binding ability of the compound and the efficacy, especially with the 5-HT1D receptor.
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It is quite volatile and decomposes at 32 °C. Its infrared spectrum shows a band at 2028 cm−1 due to CCCO. The complex can dissolve in hexane, however it slowly decomposes, losing dicarbon (C2) which goes on to form acetylenes and cumulenes in the solvent. Dimethyl sulfoxide oxidises the CCCO ligand to carbon suboxide.
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At the same time, he is building a Kandelos Agricultural Complex with the aim of being able to do the same for the deprived and remote areas of Kandelos. Registration for the Cultural and Charitable Institute was also one of the projects being undertaken at the same time as the Hexane and Kandelus Agricultural Complex.
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Speed glue is mixed with certain solvents to create a better effect. Some of these solvents are illegal and contain potentially hazardous vapors. They are considered to be inhalants. In 1995, the International Table Tennis Federation (ITTF) banned the use of all halogenated solvents, all solvents with benzene rings, and N-hexane in paddles.
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China and Vietnam provide 70% and East Africa 20% of the raw plant material. Seedlings are grown in nurseries and then transplanted into fields. It takes about 8 months for them to reach full size. The plants are harvested, the leaves are dried and sent to facilities where the artemisinin is extracted using a solvent, typically hexane.
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Soybeans are a globally important crop, providing oil and protein. In the United States, the bulk of the harvest is solvent-extracted with hexane, and the "toasted" defatted soymeal (50% protein) then makes possible the raising of farm animals (e.g. chicken, hog, turkey) on a large industrial scale. Soybean products are used in a large variety of processed foods.
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Sorption isotherms for hexane and methanol show that the adsorbent has a mesoporous structure. Presence of methyl groups on the surface provides their hydrophobic properties. PMSPH particles tend to form a continuous network in the suspension to reduce interaction of the hydrophobic groups SiCH3 with water. These particles can be viewed as 2D sheets rather than 3D solids.
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3-Methylpentane is a branched-chain alkane with the molecular formula C6H14. It is a structural isomer of hexane composed of a methyl group bonded to the third carbon atom in a pentane chain. It is of similar structure to the isomeric 2-methylpentane, which has the methyl group located on the second carbon of the pentane chain.
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Living isobutylene polymerization typically takes place in a mixed solvent system comprising a non-polar solvent, such as hexane, and a polar solvent, such as chloroform or dichloromethane, at temperatures below 0 °C. With more polar solvents polyisobutylene solubility becomes a problem. Initiators can be alcohols, halides and ethers. Co-initiators are boron trichloride, tin tetrachloride and organoaluminum halides.
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The separation of β-carotene from the mixture of other carotenoids is based on the polarity of a compound. β-Carotene is a non-polar compound, so it is separated with a non-polar solvent such as hexane. Being highly conjugated, it is deeply colored, and as a hydrocarbon lacking functional groups, it is very lipophilic.
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1,4-Dihydroxyanthraquinone, also called quinizarin, is an isomer of alizarin. Alizarin is one of ten dihydroxyanthraquinone isomers. It is soluble in hexane and chloroform, and can be obtained from the latter as red-purple crystals, melting point 277–278 °C. Alizarin changes color depending on the pH of the solution it is in, thereby making it a pH indicator.
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ATR FTIR spectrum for hexane showing percent transmittance (%T) versus wavenumber (cm−1). The two main standalone spectroscopy techniques for forensic chemistry are FTIR and AA spectroscopy. FTIR is a nondestructive process that uses infrared light to identify a substance. The attenuated total reflectance sampling technique eliminates the need for substances to be prepared before analysis.
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The refinery also released 8000 pounds of sulfur dioxide in a flare release on April 7, 2002. An accidental release on April 14, 2003, resulted in the emission of 274,438 pounds of air contaminants into the surrounding environment; including 107,280 pounds of hexane and 37,538 pounds of pentane, both of which have severe human health impacts.
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Nonpolar solvents such as hexane and carbon tetrachloride provide a higher solubility. Polar solutions, such as aqueous solutions, are brown, reflecting the role of these solvents as Lewis bases; on the other hand, nonpolar solutions are violet, the color of iodine vapour. Charge-transfer complexes form when iodine is dissolved in polar solvents, hence changing the colour.
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1]hexane-6-carboxylic acid. Ring contraction of α-diazocamphor via Wolff-rearrangement, followed by hydration from more sterically accessible endo face. Ring contractions have been used extensively to build strained ring systems, as ring size does not impede the Wolff rearrangement, but often impedes other reactions. There are many examples where the Wolff rearrangement is used to contract cyclopentanone to cyclobutane.
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The sodium compound is white, but the presence of metallic iron turns the commercial material gray. :2 Na + 2 NH3 → 2 NaNH2 \+ H2 Lithium diisopropylamide is a popular non-nucleophilic base used in organic synthesis. Unlike many other bases, the steric bulk prevents this base from acting as a nucleophile. It is commercially available, usually as a solution in hexane.
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The plant contains a resin, used as chewing gum in Kevan, Turkey, where it is called kevove rubber tree. Mastic gum of the tree has been reported to have significant antimicrobial and antifungal activity. Twenty-six compounds in hexane extract were identified. The major compounds were α-pinene 57.06%, β-pinene 9.83%, trans-pinocarveol 2.95%, trans-Verbenol 3.97%, α-Phellandren-8-ol 3.81%.
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The company refuses food ingredients made with hexane solvent extraction, choosing instead expeller pressed isolates and concentrates. In 2005, Turtle Island Foods began to purchase all of its electricity from the Blue Sky renewable energy project of the northwestern United States.Sustainability All paperboard packaging is recycled. In addition, a certain percentage of each year's Tofurky sales is donated to an environmental charity.
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This gives rise to the hope that the algae will not have to be killed in order to extract its useful oil. Several methods are available to extract the botryococcene. One that shows the most promise is the use of hexane as a solvent. If used at the proper molarity, it does not kill the majority of the Bb, while extracting the botryococcene.
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Alternatively, determination and quantification of taraxerol can also be achieved with good reliability and reproducibility using HPTLC. In this case, linear ascending development is performed (e.g. using hexane and ethyl acetate (8:2 v/v) as mobile phase) in a twin trough glass chamber on TLC aluminum plates. Quantification can be achieved by spectrodensitometric scanning at a wavelength of 420 nm.
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Perfluorohexane (), or tetradecafluorohexane, is a fluorocarbon. It is a derivative of hexane in which all of the hydrogen atoms are replaced by fluorine atoms. It is used in one formulation of the electronic cooling liquid/insulator Fluorinert for low-temperature applications due to its low boiling point of 56 °C and freezing point of −90 °C. It is odorless and colorless.
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The odors of female L. figueresi are an important stimulus for sexual attraction in males. Each female has its own unique scent. In cage experiments, male L. figueresi were more inclined towards dead females that were untreated compared to dead females that were washed in hexane, which removed their odor. The odor of females even increased the response of males to other cues.
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The main products of the company are LPG, Motor Spirit, superior kerosene, aviation turbine fuel, high speed diesel, naphtha, bitumen, lube base stocks, paraffin wax, fuel oil, hexane and petrochemical feed stocks. The wax plant at CPCL has an installed capacity of 30,000 tonnes per annum, which is designed to produce paraffin wax for manufacture of candle wax, waterproof formulations and match wax.
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Benzene has 6 hydrogen atoms – fewer than the corresponding parent alkane, hexane. The molecule is planar. The molecular orbital description involves the formation of three delocalized π orbitals spanning all six carbon atoms, while the valence bond description involves a superposition of resonance structures. It is likely that this stability contributes to the peculiar molecular and chemical properties known as aromaticity.
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Xanthopurpurin is insoluble in hexane but soluble in chloroform. It can be obtained from solutions in the latter as reddish crystals that melt at 270–273 °C. Like many dihydroxy- and trihydroxyanthraquinones, it has a purgative action, although only 1/6 as effective as 1,2,7-trihidroxyanthraquinone (anthrapurpurin). Hugh Alister McGuigan (1921), An introduction to chemical pharmacology; pharmacodynamics in relation to chemistry.
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Copra meal is used as fodder for horses and cattle. Its high oil and protein levels are fattening for stock. The protein in copra meal has been heat treated and provides a source of high-quality protein for cattle, sheep and deer, because it does not break down in the rumen. Coconut oil can be extracted using either mechanical expellers or solvents (hexane).
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Open mango stone Mango kernels Fat is extracted from dried mango kernels by hydraulic pressure,Mango oil extraction or by solvent extraction.Extraction methods In solvent extraction, hexane, a liquid hydrocarbon, is used as the extraction medium. The collected mango stones are washed with well-water soon after collection. After washing, the seeds are sun dried to reduce the moisture content to 12-15%.
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2,2-Dimethylbutane, trivially known as neohexane, is an organic compound with formula C6H14 or (H3C-)3-C-CH2-CH3. It is therefore an alkane, indeed the most compact and branched of the hexane isomers — the only one with a quaternary carbon and a butane (C4) backbone. It can be synthesised by the hydroisomerisation of 2,3-dimethylbutane using an acid catalyst.
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An LCST is observed for, e.g., polypropylene in n-hexane,J. M. G. Cowie, I. J. McEwen, Lower critical solution temperatures of polypropylene solutions, Journal of Polymer Science: Polymer Physics Edition, 1974, Volume 12, pp 441-443. polystyrene in butylacetateOliver Pfohl, Toshiaki Hino, John M. Prausnitz, Solubilities of styrene-based polymers and copolymers in common solvents, Polymer, 1995, Volume 36, pp 2065-2073.
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Natural gas is composed primarily of methane, but often contains longer-chain hydrocarbons. Hydrocarbon compounds from hexane (each molecule of which is a simple chain containing six carbon atoms, hence called C6) and heavier generally separate out ("condense") from the gas at the wellhead; this mixture is called condensate, and is usually reported as oil production, and sold to refineries the same as oil. The C2 through C5 hydrocarbons (ethane, propane, butane, and pentane) are known as natural gas liquids (NGLs), and remain in gaseous form until they are extracted at a gas processing plant.Schlumberger, Natural gas liquids accessed 2 August 2015 The division between the two classes is not perfect: some hexane, and heptane remain in the gas to be separated out as NGLs, while some butane and pentane, may separate out with the condensate.
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Soybean seed contains 18–19% oil. To extract soybean oil from seed, the soybeans are cracked, adjusted for moisture content, rolled into flakes and solvent-extracted with commercial hexane. The oil is then refined, blended for different applications, and sometimes hydrogenated. Soybean oils, both liquid and partially hydrogenated, are exported abroad, sold as "vegetable oil", or end up in a wide variety of processed foods.
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In this method, oils from the algae are extracted through repeated washing, or percolation, with an organic solvent such as hexane or petroleum ether, under reflux in a special glassware. The value of this technique is that the solvent is reused for each cycle. Enzymatic extraction uses enzymes to degrade the cell walls with water acting as the solvent. This makes fractionation of the oil much easier.
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The solvents used in rubber cement present some hazards, including flammability and potential for abuse as inhalants. Therefore, as with any adhesive containing solvents, rubber cement should be used in an open area. Also, care needs be taken to avoid heat sources, as n-heptane and n-hexane are highly flammable. Rubber cement and rubber cement thinners that contain acetone will damage polished surfaces and many plastics.
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Cucurbalsaminol A or cucurbita-5,23(E)-diene-3β,12β,25-triol, is a chemical compound with formula , found in the Balsam apple vine (Momordica balsamina). It is a cucurbitane-type triterpenoid, related to cucurbitacin, isolated by C. Ramalhete and others in 2009. Cucurbalsaminol A is an amorphous powder soluble in methanol and ethyl acetate but insoluble in n-hexane. Unlike Cucurbalsaminol B, it is not cytotoxic.
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Cucurbalsaminol B or 7β-methoxycucurbita-5,23(E)-diene-3β,12β,25-triol, is a chemical compound with formula , found in the Balsam apple vine (Momordica balsamina). It is a cucurbitane-type triterpenoid, related to cucurbitacin, isolated by C. Ramalhete and others in 2009. Cucurbalsaminol B is an amorphous powder soluble in methanol and ethyl acetate but insoluble in n-hexane. It is cytotoxic at about 50 μM.
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Balsaminapentaol or cucurbita-5,25-diene-3β,7β,23(R),24(R),29-pentaol, is a chemical compound with formula , found in the Balsam apple vine (Momordica balsamina). It is a cucurbitane-type triterpenoid, related to cucurbitacin, isolated by C. Ramalhete and others in 2009. Balsaminepentaol is an amorphous powder soluble in methanol and ethyl acetate but insoluble in n-hexane. It is cytotoxic at about 50 μM.
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Balsaminol A or cucurbita-5,24-diene-3β,7β,23(R),29-tetraol, is a chemical compound with formula , found in the Balsam apple vine (Momordica balsamina). It is a cucurbitane-type triterpenoid, related to cucurbitacin, isolated by C. Ramalhete and others in 2009. Balsaminol A is an amorphous powder soluble in methanol and ethyl acetate but insoluble in n-hexane. It is cytotoxic at about 50 μM.
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Balsaminol B or 7β-methoxycucurbita-5,24-diene-3β,23(R),29-triol, is a chemical compound with formula , found in the balsam apple vine (Momordica balsamina). It is a cucurbitane-type triterpenoid, related to cucurbitacin, isolated by C. Ramalhete and others in 2009. Balsaminol B is an amorphous powder soluble in methanol and ethyl acetate, but insoluble in n-hexane. It is cytotoxic at about 50 μM.
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The refinery was modified to handle imported and Bombay High crude. The refinery also produces a wide range of specialty products such as benzene, toluene, MTO, food grade hexane, solvents and LABFS. The Gujarat Refinery is the first refinery in India to have completed the diesel hydrodesulfurization project in June 1999, when the refinery started production of HSD with low sulfur content of 0.25% wt (max).
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Alkanes with five or more carbon atoms are named by adding the suffix -ane to the appropriate numerical multiplier prefix with elision of any terminal vowel (-a or -o) from the basic numerical term. Hence, pentane, C5H12; hexane, C6H14; heptane, C7H16; octane, C8H18; etc. The prefix is generally Greek, however alkanes with a carbon atom count ending in nine, for example nonane, use the Latin prefix non-.
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Hydrogen required for this reaction can be produced by aqueous phase catalytic reforming of sorbitol. :19 C6H14O6 → 13 C6H14 \+ 36 CO2 \+ 42 H2O The above chemical reaction is exothermic, and 1.5 moles of sorbitol generate approximately 1 mole of hexane. When hydrogen is co-fed, no carbon dioxide is produced. Sorbitol based polyols are used in the production of polyurethane foam for the construction industry.
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Hydrogen bonds between molecules of liquid water The hydrophobic effect represents the tendency of water to exclude non-polar molecules. The effect originates from the disruption of highly dynamic hydrogen bonds between molecules of liquid water. Polar chemical groups, such as OH group in methanol do not cause the hydrophobic effect. However, a pure hydrocarbon molecule, for example hexane, cannot accept or donate hydrogen bonds to water.
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The discovery of carbomycin was first reported by Fred W. Tanner Jr. of Pfizer. Carbomycin can be isolated from Streptomyces halstedii via extraction from a fermentation broth and purified through crystallization from alcohol-water mixtures. Carbomycin can be further purified with the use of preparative thin-layer chromatography. The most efficient solvent is one consisting of ethanol-hexane-water in 90-10-0.15 volume ratio.
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Most of the engines of that time could not exceed 200 rpm due to their ignition and induction systems. The first practical engine, Lenoir's, ran on illuminating gas (coal gas). It wasn't until 1883, that Daimler created an engine that ran on liquid petroleum, a fuel called Ligroin which has a chemical makeup of Hexane-N. The fuel is also known as petroleum naphtha.
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The production of packaging material is the main source of the air pollution that is being spread globally. Some emissions comes from accidental fires or activities that includes incineration of packaging waste that releases vinyl chloride, CFC, and hexane. For a more direct course, emissions can originate in land fill sites which could release CO2 and methane. Most CO2 comes from steel and glass packaging manufacturing.
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Straight-chain alkanes are sometimes indicated by the prefix "n-" or "n-"(for "normal") where a non-linear isomer exists. Although this is not strictly necessary, the usage is still common in cases where there is an important difference in properties between the straight-chain and branched- chain isomers, e.g., n-hexane or 2- or 3-methylpentane. Alternative names for this group are: linear paraffins or n-paraffins. The members of the series (in terms of number of carbon atoms) are named as follows: ; methane: CH4 – one carbon and 4 hydrogen ; ethane : C2H6 – two carbon and 6 hydrogen ; propane: C3H8 – three carbon and 8 hydrogen ; butane : C4H10 – four carbon and 10 hydrogen ; pentane: C5H12 – five carbon and 12 hydrogen ; hexane : C6H14 – six carbon and 14 hydrogen The first four names were derived from methanol, ether, propionic acid and butyric acid, respectively (hexadecane is also sometimes referred to as cetane).
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P4-t-Bu is one of the strongest neutral nitrogenous bases with an extrapolated pKa value of 42.1 in acetonitrile and is compared to the strong base DBU with a pKa value of 24.3 by 18 orders of magnitude more basic. The compound is very well soluble in non-polar solvents, such as hexane, toluene or tetrahydrofuran, and is usually commercially available as a 0.8 to 1 molar solution in hexane. Already in weakly acidic media protonation produces the extremely delocalized and soft P4-t-Bu-H cation and causes besides a very strong solubilization effect also an extreme acceleration of addition reactions even at temperatures below -78 °C. P4-t-Bu owes its extraordinarily high basicity with low nucleophilicity to its very high steric hindrance and the involvement of many donor groups in conjugation with the spatially demanding structure of the cation formed by protonation.
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When heated in absence of oxygen, WS2 does not melt but decomposes to tungsten and sulfur, but only at 1250 °C. Historically monolayer WS2 was isolated using chemical exfoliation via intercalation with lithium from n-butyl lithium (in hexane), followed by exfoliation of the Li intercalated compound by sonication in water. WS2 also undergoes exfoliation by treatment with various reagents such as chlorosulfonic acid and the lithium halides.
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A common historical example of azeotropic distillation is its use in dehydrating ethanol and water mixtures. For this, a near azeotropic mixture is sent to the final column where azeotropic distillation takes place. Several entrainers can be used for this specific process: benzene, pentane, cyclohexane, hexane, heptane, isooctane, acetone, and diethyl ether are all options as the mixture. Of these benzene and cyclohexane have been used the most extensively.
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This study was done using transmission electron microscopy. Another study was done to see how washing the nanobuds in different solvents, such as toluene, decaline, and hexane, would affect the fullerenes and their interaction with the nanotubes. Of the solvents that were tested, none of them resulted in fullerenes being dissolved in the solvent. This continues to defend the discovery that the bond between the two is significantly strong.
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Organic solvent extraction is the most common and most economically important technique for extracting aromatics in the modern perfume industry. Raw materials are submerged and agitated in a solvent that can dissolve the desired aromatic compounds. Commonly used solvents for maceration/solvent extraction include hexane, and dimethyl ether. In organic solvent extraction, aromatic compounds as well as other hydrophobic soluble substances such as wax and pigments are also obtained.
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The removal of the reaction water by azeotropic distillation with benzene (as carrier) shortens the reaction time to 10h, whereby after fractional distillation DVTOSU is obtained in 75% yield with a boiling point of 138-141 °C at 12 Torr. Cyclic acetals can also be produced from 1,3-diols with propenal under very gentle (room temperature) and continuous process conditions followed by continuous extraction with, for example, n-hexane in yields of up to 90%.
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The refinery, located south of the Texas/Oklahoma border and seven miles north of Sunray, Texas, included a spherical tank containing half a million gallons of pentane and hexane. Vapors escaped from the tank and migrated downhill toward other installations. The vapors ignited, probably near an asphalt plant and travelled back toward the tank. There the flames consumed the escaping vapors, forcing firefighters to use water to cool nearby tanks to prevent further spread.
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A wide array of biphasic solvent mixtures are available to the CCC practitioner including the combination n-hexane (or heptane), ethyl acetate, methanol and water in different proportions. This basic solvent system is sometimes referred to as the HEMWat solvent system. The choice of solvent system may be guided by perusal of the CCC literature. The familiar technique of thin layer chromatography may also be employed to determine an optimal solvent system.
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Hexanes are commonly used in chromatography as a non-polar solvent. Higher alkanes present as impurities in hexanes have similar retention times as the solvent, meaning that fractions containing hexane will also contain these impurities. In preparative chromatography, concentration of a large volume of hexanes can result in a sample that is appreciably contaminated by alkanes. This may result in a solid compound being obtained as an oil and the alkanes may interfere with analysis.
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Both PXA and PXB were discovered in 2001, and their preparation by isolation from Phomopsis fungal cultures was described in the corresponding publication. Briefly, a MeOH extract of a Phomopsis culture is mixed with H2O and washed with hexane. The aqueous phase is then dried and the residue is dissolved in EtOAc, washed with H2O, concentrated and repeatedly purified by size-exclusion chromatography. The resulting mixture of PXA and PXB is separated by HPLC.
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Canola oil Canola oil is made at a processing facility by slightly heating and then crushing the seed. Almost all commercial canola oil is then extracted using hexane solvent which is recovered at the end of processing. Finally, the canola oil is refined using water precipitation and organic acid to remove gums and free fatty acids, filtering to remove color, and deodorizing using steam distillation. The average density of canola oil is 0.92 g/mL ().
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A mixture of sorbitol and potassium nitrate has found some success as an amateur solid rocket fuel. Sorbitol is identified as a potential key chemical intermediate for production of fuels from biomass resources. Carbohydrate fractions in biomass such as cellulose undergo sequential hydrolysis and hydrogenation in the presence of metal catalysts to produce sorbitol. Complete reduction of sorbitol opens the way to alkanes, such as hexane, which can be used as a biofuel.
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Neem seed oil can also be obtained by solvent extraction of the neem seed, fruit, oil, cake or kernel. A large industry in India extracts the oil remaining in the seed cake using hexane. This solvent- extracted neem oil is of a lower quality as compared to the standard cold pressed neem oil and is mostly used for soap manufacturing. Neem cake is a by- product obtained in the solvent extraction process for neem oil.
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Extracted egg oil In alchemy, the oil was traditionally extracted from the yolk by a fairly simple process, by which fifty eggs yielded approximately five ounces of oil. Modern methods of production include liquid–liquid extraction using common solvents such as hexane, petroleum ether, chloroform and ethanol. Unlike traditional egg oil produced by heat, solvent extracted product also contains immunoglobulins which are destroyed at higher temperatures. There are only a few commercial producers globally.
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Intermolecular forces are the main constituent of changes in the enthalpy of a mixture. Stronger attractive forces between the mixed molecules, such as hydrogen-bonding, induced-dipole, and dipole-dipole interactions result in a lower enthalpy of the mixture and a release of heat. If strong interactions only exist between like-molecules, such as H-bonds between water in a water-hexane solution, the mixture will have a higher total enthalpy and absorb heat.
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Hexane-extraction techniques indicate presence of alkaloid toxins in Brachypylina. Toxins appear to be biosynthesized in adult mites, as nymph and larval stages of the arachnid do not carry the toxins. Experimental analysis of this species of mite show alkaloid toxins are found almost exclusively in the opisthonotal glands of mites of the Scheloribatidae. Oil glands of the mite contain the toxins and are then released internally as the amphibian digests the arthropod.
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The relative static permittivity of a solvent is a relative measure of its chemical polarity. For example, water is very polar, and has a relative static permittivity of 80.10 at 20 °C while n-hexane is non-polar, and has a relative static permittivity of 1.89 at 20 °C. This information is important when designing separation, sample preparation and chromatography techniques in analytical chemistry. The correlation should, however, be treated with caution.
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In terms of mechanism, the oxidative polymerization using ferric chloride, a radical pathway has been proposed. Proposed mechanisms for ferric chloride oxidative polymerizations of thiophenes. Polymerization was only observed in solvents where the catalyst was either partially or completely insoluble (chloroform, toluene, carbon tetrachloride, pentane, and hexane, and not diethyl ether, xylene, acetone, or formic acid). The polymerization may occur at the surface of solid ferric chloride.. Quantum mechanical calculations also point to a radical mechanism.
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See sigma bonds and pi bonds for LCAO descriptions of such bonding. Molecules that are formed primarily from non-polar covalent bonds are often immiscible in water or other polar solvents, but much more soluble in non-polar solvents such as hexane. A polar covalent bond is a covalent bond with a significant ionic character. This means that the two shared electrons are closer to one of the atoms than the other, creating an imbalance of charge.
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Diallyl disulfide has a strong garlic smell. It is a clear, yellowish liquid which boils at 138–139 °C (for the typical 80% purity) and has its flash point at 50 °C, a density of about 1.0 g/mL and a vapor pressure of 1 mmHg at 20 °C. It is non-polar; therefore, diallyl disulfide is insoluble in water and is soluble in fats, oils, lipids, and non- polar solvents such as hexane or toluene.
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It is used as a solvent in some brands of correction fluid. Cyclohexane is sometimes used as a non-polar organic solvent, although n-hexane is more widely used for this purpose. It is frequently used as a recrystallization solvent, as many organic compounds exhibit good solubility in hot cyclohexane and poor solubility at low temperatures. Cyclohexane is also used for calibration of differential scanning calorimetry (DSC) instruments, because of a convenient crystal- crystal transition at −87.1 °C.
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1-Oleoyl-2-palmitoyl-phosphatidylcholine Phosphatidylcholines (PC) are a class of phospholipids that incorporate choline as a headgroup. They are a major component of biological membranes and can be easily obtained from a variety of readily available sources, such as egg yolk or soybeans, from which they are mechanically or chemically extracted using hexane. They are also a member of the lecithin group of yellow-brownish fatty substances occurring in animal and plant tissues. Dipalmitoyl phosphatidylcholine (a.k.a.
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In the solvent extraction method, the flowers are agitated in a vat with a solvent such as hexane, which draws out the aroma compounds as well as other soluble substances such as wax and pigments. The extract is subjected to vacuum processing which removes the solvent for re-use. The remaining waxy mass is known as a concrete. The concrete is then mixed with alcohol which dissolves the aromatic constituents, leaving behind the wax and other substances.
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SANTOS, Rogério Nunes dos; SILVA, Maria Goretti de Vasconcelos, and BRAZ FILHO, Raimundo (2008). Constituintes químicos do caule de Senna reticulata Willd. (Leguminoseae) ("Chemical constituents isolated from the wood of Senna reticulata Willd") Química Nova [online], volume 31 issue 8, pages 1979--1981 (in Portuguese). "It is the first report of 1,3,8-trihydroxyanthraquinone and 3-methoxy-1,6,8-trihydroxyanthraquinone in higher plants." The substance is soluble in ethanol and chloroform but not in n-hexane, and melts at 283 °C.
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Many expellers add heat and pressure, in order to increase the amount of oil extracted. If the temperature does not exceed 120 °F, the oil can be called "cold-pressed". In modern vegetable oil production, oils are usually extracted chemically, using a solvent such as hexane. Chemical extraction is cheaper and more efficient than mechanical extraction, at a large scale, leaving only 0.5–0.7% of the oil in the plant solids, as compared to 6–14% for mechanical extraction.
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The seeds are first ground to a paste before being washed with a solvent to release the fat in the seed. Next, the solvent (Hexane is the standard) is removed using heat in a sealed chamber and distilled, leaving virtually no detectable levels of the solvent used. Solvent extraction has been able to achieve 95% oil yields. The high productivity is the main advantage of this process, it also requires less maintenance than other methods of extraction.
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Therefore, other physical methods for liquid exfoliation are still under development. A laser-assisted method developed by Zheng and co-workers showed a promising yield of up to 90% within 5 minutes. The laser photon interacts with the surface of bulk black phosphorus crystal, causing a plasma and solvent bubbles to weaken the interlayer interaction. Depending on the laser energy, solvent (ethanol, methanol, hexane, etc.) and irradiation time, the layer number and lateral size of the phosphorene were controlled.
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Cerevisterol was first discovered in 1928 as a component of crude yeast (Saccharomyces cerevisiae) sterols remaining from the manufacture of the related ergosterol. Chemists Edna M. Honeywell and Charles E. Bills purified the compound and reported some of its properties in a 1932 publication. They noted its high melting point (265.3 °C) relative to other sterols, and insolubility in the organic solvent hexane. These characteristics facilitated its purification, and they were able to obtain of cerevisterol from of dry yeast.
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When the carbene is stabilized by a metal the selectivity increases. The compound dirhodium tetraacetate is found to be especially effective. In a typical reaction ethyl diazoacetate (a well-known carbene precursor) and dirhodium tetraacetate react with hexane; the insertion into a C−H bond occurs 1% on one of the methyl groups, 63% on the alpha-methylene unit and 33% on the beta- methylene unit. The first such reaction was reported in 1981 by Teyssié Transition-metal-catalysed reactions of diazoesters.
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Tea made with the leaves of the Q. amara, is used against malaria in the traditional medicine of French Guiana. The leaves hexane from Q. amara was found to have high suppressive activity, at a concentration from 100 mg/kg body weight in mouse. In 2006, a study found that Simalikalactone D should be responsible for the antimalarial activity. In 2009, a new quassinoid was discovered, the simalikalactone E. This molecule inhibited the growth of P. falciparum in vitro by 50%.
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A bottle of rubber cement, showing a brush built into its cap and a photo about to be cemented to graph paper. Rubber cement (cow gum in British English) is an adhesive made from elastic polymers (typically latex) mixed in a solvent such as acetone, hexane, heptane or toluene to keep it fluid enough to be used. This makes it part of the class of drying adhesives: as the solvents quickly evaporate, the rubber solidifies, forming a strong yet flexible bond.
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A significant characteristic of Janus nanoparticles is the capability of having both hydrophilic and hydrophobic parts. Many research groups have investigated the surface activities of nanoparticles with amphiphilic properties. In 2006, Janus nanoparticles, made from gold and iron oxides, were compared with their homogeneous counterparts by measuring the ability of the particles to reduce the interfacial tension between water and n-hexane. Experimental results indicated Janus nanoparticles are considerably more surface-active than homogeneous particles of comparable size and chemical nature.
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Chipotle and imitation chicken quesadilla Soy protein isolates or soybean flour and gluten are usually used as foundation for most meat analogs that are available on the market. Soy protein isolate is a highly pure form of soy protein with a minimum protein content of 90%. The process of extracting the protein from the soybeans starts with the dehulling, or decortication, of the seeds. The seeds are then treated with solvents such as hexane in order extract the oil from them.
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Isomerases catalyze changes within one molecule. They convert one isomer to another, meaning that the end product has the same molecular formula but a different physical structure. Isomers themselves exist in many varieties but can generally be classified as structural isomers or stereoisomers. Structural isomers have a different ordering of bonds and/or different bond connectivity from one another, as in the case of hexane and its four other isomeric forms (2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane).
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Egg lecithin is usually extracted chemically using ethanol, acetone, petroleum ether but not benzene or hexane due to restrictions on residual solvents by the pharmaceutical regulations.ICH Topic Q3C (R4) Impurities: Guideline for Residual Solvents It is an emulsifier, especially for parenteral use since it does not need to be metabolized. In aqueous solution, its phospholipids can form either liposomes, bilayer sheets, micelles, or lamellar structures, depending on hydration and temperature. This results in a type of surfactant that is usually classified as amphipathic.
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Purpurin is a crystalline solid, that forms orange needles melting at ,CRC Handbook of Chemistry & Physics, 90th Ed. but becomes red when dissolved in ethanol, and yellow when dissolved with alkalis in boiling water. It is insoluble in hexane but soluble in chloroform, and can be obtained from chloroform as reddish needles. Unlike alizarin, purpurin is dissolved by boiling in a solution of aluminum sulfate, from which it can be precipitated by acid. This procedure can be used to separate the two dyes.
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Often, the algae is dehydrated, and then a solvent such as hexane is used to extract energy-rich compounds like triglycerides from the dried material. Then, the extracted compounds can be processed into fuel using standard industrial procedures. For example, the extracted triglycerides are reacted with methanol to create biodiesel via transesterification. The unique composition of fatty acids of each species influences the quality of the resulting biodiesel and thus must be taken into account when selecting algal species for feedstock.
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Biogasoline, or biopetrol (British English) is a gasoline produced from biomass such as algae. Like traditionally produced gasoline, it contains between 6 (hexane) and 12 (dodecane) carbon atoms per molecule and can be used in internal-combustion engines. Biogasoline is chemically different from biobutanol and bioethanol, as these are alcohols, not hydrocarbons. Companies such as Diversified Energy Corporation are developing approaches to take triglyceride inputs and through a process of deoxygenation and reforming (cracking, isomerizing, aromatizing, and producing cyclic molecules) producing biogasoline.
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Caproic acid, also known as hexanoic acid, is the carboxylic acid derived from hexane with the chemical formula . It is a colorless oily liquid with an odor that is fatty, cheesy, waxy, and like that of goats or other barnyard animals. It is a fatty acid found naturally in various animal fats and oils, and is one of the chemicals that gives the decomposing fleshy seed coat of the ginkgo its characteristic unpleasant odor.Ginkgo.html It is also one of the components of vanilla.
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This allows large quantities of pure resins to be extracted in a very clean process without the use of solvents, making for a more purified hashish. Chemical separation methods generally use a solvent such as ethanol, butane or hexane to dissolve the lipophilic desirable resin. Remaining plant materials are filtered out of the solution and sent to the compost. The solvent is then evaporated, or boiled off (purged) leaving behind the desirable resins, called honey oil, "hash oil", or just "oil".
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The costs of this extraction process are estimated to be much greater than hexane extraction. Supercritical CO2 can also be used as a solvent. In this method, CO2 is liquefied under pressure and heated to the point that it becomes supercritical (having properties of both a liquid and a gas), allowing it to act as a solvent. Other methods are still being developed, including ones to extract specific types of oils, such as those with a high production of long-chain highly unsaturated fatty acids.
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The m/z=57 butyl cation is the base peak, and other most abundant peaks in the spectrum are alkyl carbocations at m/z=15, 29, 43 Da. The possible mechanisms for EI ionization spectra of hexane Branched alkanes have somewhat weaker molecular ion peaks in the spectra. They tend to fragment at the branched point. For the 2,3-dimethylbutane, an isopropyl cation peak (m/z=43) is very strong. Branched alkane Cycloalkanes have relatively intense molecular ion peaks (two bonds have to break).
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It is a whitish crystalline substance, neutral and tasteless, melting at 266–268 °C. It is sparingly soluble in water or other highly polar solvents, as well as in apolar solvents like hexane, but is soluble in ether, ethanol and methanol, and can be efficiently extracted from the plant by pressurized ethanol or acetone at 100 °C. The name charantin has also been used by A. Parkash and other for a different compound, a peptide with molecular mass 9.7 kDa, also isolated from bitter melon seeds.
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After a high suicide rate in a Foxconn facility in China making iPads and iPhones, albeit a lower rate than that of China as a whole, workers were forced to sign a legally binding document guaranteeing that they would not kill themselves. Workers in factories producing Apple products have also been exposed to n-hexane, a neurotoxin that is a cheaper alternative than alcohol for cleaning the products.Workers poisoned while making iPhones ABC News, October 25, 2010.Dirty Secrets ABC News Foreign Correspondent, October 26, 2010.
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Since the molecule has a hydroxyl (-OH) group, it is frequently bound to other lipids including glycerols; most analytical methods, therefore, utilise a strong alkali (KOH or NaOH) to saponify the ester linkages. Typical extraction solvents include 6% KOH in methanol. The free sterols are then separated from the polar lipids by partitioning into a less polar solvent such as hexane. Prior to analysis, the hydroxyl group is frequently derivatised with BSTFA (bis-trimethyl silyl trifluoroacetamide) to replace the hydrogen with the less exchangeable trimethylsilyl (TMS) group.
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This experiment had a proton precessional magnetometer to measure the Earth's magnetic field at altitudes ranging from 514 to 3714 km and at latitudes between ± 33.4°. The measurements were made on command as the spacecraft passed seven minitrack stations in North and South America and one each in Australia and South Africa. When switched on by command, the polarization coil around the proton sample (normal hexane) was turned on for 2 s followed by a 2-s readout of the precession signal. Several readings were taken during each pass over a station.
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As an example, under strong basic conditions (e.g. sodium hydroxide), hexane-2,5-dione (compound A in Figure 1) can cyclize via intramolecular aldol reaction to form the 3-methylcyclopent-2-en-1-one (compound B). The mechanism of the intramolecular aldol reaction involves formation of a key enolate intermediate followed by an intramolecular nucleophilic addition process. First, hydroxide abstracts the α-hydrogen on a terminal carbon to form the enolate. Next, a nucleophilic attack of the enolate on the other keto group forms a new carbon-carbon bond (red) between carbons 2 and 6.
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This type of decanter, instead of having three exits (oil, water, and solids), has only two. The water is expelled by the decanter coil together with the pomace, resulting in a wetter pomace that is much harder to process industrially. Many pomace oil extraction facilities refuse to work with these materials because the energy costs of drying the pomace for the hexane oil extraction often make the extraction process sub-economical. In practice, then, the two phases decanter solves the phenol washing problem but increases the residue management problem.
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Natural gasoline is a liquid hydrocarbon mixture condensed from natural gas, similar to common gasoline (petrol) derived from petroleum. The chemical composition of natural gasoline is mostly five- and six-carbon alkanes (pentanes and hexanes) with smaller amounts of alkanes with longer chains.Sheng Wang, Ying Zhang, Mao-Gang He, Xiong Zheng, and Li-Bin Chen (2014): "Thermal Diffusivity and Speed of Sound of Saturated Pentane from Light Scattering". International Journal of Thermophysics, volume 35, pages 1450–1464. . Quote: "ethane 2.4% w/w, butane 1.3%, pentane 67.1%, hexane 22.0%, heptane 5.7%, and octane 1.5 %".
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Live crude is heated in a furnace or heat exchanger to an elevated temperature. The crude oil is fed to a stabilizer which is typically a tray or packed tower column that achieves a partial fractionation or distillation of the oil. The heavier components, pentane (C5H12), hexane (C6H14), and higher hydrocarbons (C7+), flow as liquid down through the column where the temperature is increasingly higher. At the bottom of the column, some of the liquid is withdrawn and circulated through a reboiler which adds heat to the tower.
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In 2006, Vadim A. Soloshonok introduced the term Enantiomer self-disproportionation or self-disproportionation of enantiomers. He investigated achiral separations of several trifluoromethyl compounds. Enantiomer self-disproportionation (S)-trifluoromethyl substrate By column chromatography on regular silica gel with a hexane / ethyl acetate eluent (5:1), a 66.6% ee sample of a trifluoromethyl substrate is separated into several fractions ranging from 8.1% ee for the first fraction collected to > 99.9% ee for the last fraction collected. A presence of a strong electronegative group in the substrate such as the trifluoromethyl group is a prerequisite.
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The Madelung synthesis is a chemical reaction that produces (substituted or unsubstituted) indoles by the intramolecular cyclization of N-phenylamides using strong base at high temperature.The Madelung synthesis was reported in 1912 by Walter Madelung, when he observed that 2-phenylindole was synthesized using N-benzoyl-o-toluidine and two equivalents of sodium ethoxide in a heated, airless, reaction. Common reaction conditions include use of sodium or potassium alkoxide as base in hexane or tetrahydrofuran solvents, at temperatures ranging between 200–400 °C. A hydrolysis step is also required in the synthesis.
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Furthermore, increasing the amphiphilic character of the particles can increase the interfacial activity. The ability of Janus nanoparticles to lower interfacial tension between water and n-hexane confirmed previous theoretical predictions on their ability to stabilize Pickering emulsions. In 2007, the amphiphilic nature of the Janus nanoparticles was examined by measuring the adhesion force between the atomic force microscopy (AFM) tip and the particle surface. The stronger interactions between the hydrophilic AFM tip and the hydrophilic side of the Janus nanoparticles were reflected by a greater adhesion force.
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The exact nature of the poison is still unclear. In the U.S. outbreak, the source of the fish was traced by the Centers for Disease Control and Prevention, and studies of other fish from the same sources showed a hexane-soluble (and hence non-polar lipid) substance that induced similar symptoms in mice; other food- borne poisons commonly found in fish could not be detected. It cannot be inactivated by cooking, as all six CDC cases had consumed cooked or fried fish. Palytoxin has been proposed as a disease model.
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The order of strength/weakness depends on the coating (stationary phase) of the TLC plate. For silica gel-coated TLC plates, the eluent strength increases in the following order: perfluoroalkane (weakest), hexane, pentane, carbon tetrachloride, benzene/toluene, dichloromethane, diethyl ether, ethyl acetate, acetonitrile, acetone, 2-propanol/n-butanol, water, methanol, triethylamine, acetic acid, formic acid (strongest). For C18-coated plates the order is reverse. In other words, when the stationary phase is polar and the mobile phase is nonpolar, the method is normal-phase as opposed to reverse- phase.
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This means that if a mixture of ethyl acetate and hexane as the mobile phase is used, adding more ethyl acetate results in higher Rf values for all compounds on the TLC plate. Changing the polarity of the mobile phase will normally not result in reversed order of running of the compounds on the TLC plate. An eluotropic series can be used as a guide in selecting a mobile phase. If a reversed order of running of the compounds is desired, an apolar stationary phase should be used, such as C18-functionalized silica.
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Microtox tests for sediment and soil differ in the way the matrix is prepared for contact with Allivibrio fischeri. To obtain a representative soil or sediment sample, it is necessary to conduct an elutriate test. Sediment elutriates can be prepared through extraction with either distilled water, saline water, or an organic solvent such as methylene chloride, or hexane. To run an elutriate test a soil sample is mixed with an extractant for a period of time, then allowed to settle and a sample is taken from the extract.
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The upper critical solution temperature (UCST) or upper consolute temperature is the critical temperature above which the components of a mixture are miscible in all proportions. The word upper indicates that the UCST is an upper bound to a temperature range of partial miscibility, or miscibility for certain compositions only. For example, hexane-nitrobenzene mixtures have a UCST of 19 °C, so that these two substances are miscible in all proportions above 19 °C but not at lower temperatures.P.W. Atkins and J. de Paula, "Atkins' Physical Chemistry" (8th edn, W.H. Freeman 2006) p.
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Since the molecule has a hydroxyl (-OH) group, it is frequently bound to other lipids including fatty acids; most analytical methods, therefore, utilise a strong alkali (KOH or NaOH) to saponify the ester linkages. Typical extraction solvents include 6% KOH in methanol. The free sterols and stanols (saturated sterols) are then separated from the polar lipids by partitioning into a less polar solvent such as hexane. Prior to analysis, the hydroxyl group is frequently derivatised with BSTFA (bis- trimethyl silyl trifluoroacetamide) to replace the hydrogen with the less exchangeable trimethylsilyl (TMS) group.
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Ethanol is a versatile solvent, miscible with water and with many organic solvents, including acetic acid, acetone, benzene, carbon tetrachloride, chloroform, diethyl ether, ethylene glycol, glycerol, nitromethane, pyridine, and toluene. Its main use as a solvent is in making tincture of iodine,cough syrups etc. It is also miscible with light aliphatic hydrocarbons, such as pentane and hexane, and with aliphatic chlorides such as trichloroethane and tetrachloroethylene. Ethanol's miscibility with water contrasts with the immiscibility of longer-chain alcohols (five or more carbon atoms), whose water miscibility decreases sharply as the number of carbons increases.
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Acyclic aliphatic/non-aromatic compound (butane) Cyclic aliphatic/non-aromatic compound (cyclobutane) In organic chemistry, hydrocarbons (compounds composed solely of carbon and hydrogen) are divided into two classes: aromatic compounds and aliphatic compounds (; G. aleiphar, fat, oil), also known as non-aromatic hydrocarbons. Aliphatics can be cyclic; however, hydrocarbons with conjugated pi-systems that obey Hückel's rule are instead considered to be aromatic. Aliphatic compounds can be saturated, like hexane, or unsaturated, like hexene and hexyne. Open-chain compounds (whether straight or branched) contain no rings of any type, and are thus aliphatic.
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Liquid acetic acid is a hydrophilic (polar) protic solvent, similar to ethanol and water. With a moderate relative static permittivity (dielectric constant) of 6.2, it dissolves not only polar compounds such as inorganic salts and sugars, but also non-polar compounds such as oils as well as polar solutes. It is miscible with polar and non-polar solvents such as water, chloroform, and hexane. With higher alkanes (starting with octane), acetic acid is not miscible at all compositions, and solubility of acetic acid in alkanes declines with longer n-alkanes.
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A. paraponerae utilize both visual and chemical cues to locate injured or freshly killed hosts for feeding and egg-laying. These injuries species are often the result of interspecies aggression and serve as ideal hosts for A. paraponerae to lay their egg on. Studies have shown that A. paraponerae can distinguish among different ants based on body size. When ant workers of varying species and sizes were treated with hexane to remove species-specific chemical signatures, A. paraponerae was found to prefer larger P. clavata over other tested species.
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Trimethylborane was first described in 1862 by Edward Frankland, who also mentioned its adduct with ammonia. Due to its dangerous nature the compound was no longer studied until 1921, when Alfred Stock and Friedrich Zeidler took advantage of the reaction between boron trichloride gas and dimethylzinc. Although the substance can be prepared using Grignard reagents the output is contaminated by unwanted products from the solvent. Trimethylborane can be made on a small scale with a 98% yield by reacting trimethylaluminium in hexane with boron tribromide in dibutyl ether as a solvent.
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Acetoxy group can be introduced into hydroxyl of 7-hydroxy-8-iodocoumarin, which is used to create vaginol or vaginidiol with an isopropyl Grignard reagent and commercially available epoxy aldehydes. Subsequent acid-catalysed fragmentation of vaginol with dichloromethane in trifluoroacetic acid yields angelicin. The compound can be isolated from natural sources, albeit this affords a low yield due to the prevalence of other furanocoumarins. The popular technique is air drying the aerial parts and ground roots of plant followed by n-hexane extraction and column chromatography over silica gel.
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Methyl sodium adopts a polymeric structure consisting of interconnected [NaCH3]4 clusters. When the organic substituents are bulky and especially in the presence of chelating ligands like TMEDA, the derivatives are more soluble. For example, [NaCH2SiMe3]TMEDA is soluble in hexane. Crystals have been shown to consist of chains of alternating Na(TMEDA)+ and CH2SiMe groups with Na–C distances ranging from 2.523(9) to 2.643(9) Å.William Clegg, Ben Conway, Alan R. Kennedy, Jan Klett, Robert E. Mulvey, Luca Russo "Synthesis and Structures of [(Trimethylsilyl)methyl]sodium and -potassium with Bi- and Tridentate N-Donor Ligands" Eur.
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Lecithin was first isolated in 1845 by the French chemist and pharmacist Théodore Gobley. In 1850, he named the phosphatidylcholine lécithine. Gobley originally isolated lecithin from egg yolk--λέκιθος lekithos is "egg yolk" in Ancient Greek--and established the complete chemical formula of phosphatidylcholine in 1874; in between, he had demonstrated the presence of lecithin in a variety of biological matters, including venous blood, in human lungs, bile, human brain tissue, fish eggs, fish roe, and chicken and sheep brain. Lecithin can easily be extracted chemically using solvents such as hexane, ethanol, acetone, petroleum ether or benzene; or extraction can be done mechanically.
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A brief review of the techniques available for measuring the volume viscosity of liquids can be found in Dukhin & Goetz and Sharma (2019). One such method is by using an acoustic rheometer. Below are values of the volume viscosity for several Newtonian liquids at 25°C (reported in cP): methanol - 0.8 ethanol - 1.4 propanol - 2.7 pentanol - 2.8 acetone - 1.4 toluene - 7.6 cyclohexanone - 7.0 hexane - 2.4 Recent studies have determined the volume viscosity for a variety of gases, including carbon dioxide, methane, and nitrous oxide. These were found to have volume viscosities which were hundreds to thousands of times larger than their shear viscosities.
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In the next article, Craig was inspired by the work of Martin and Synge with partition chromatography to develop an apparatus that would separate compounds based on their distribution constant (K which coincides with partition coefficient). It was shown that a solvent system composed of benzene, n-hexane, methanol and water would separate mixtures of organic acids. It is remarkable that the mathematical theory developed hand-in-hand with the progression of applications. Craig continued to pursue this method of separation by testing different compounds, formulating biphasic solvent systems, and most importantly developing a commercially viable instrument.
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Drip gas, so named because it can be drawn off the bottom of small chambers (called drips) sometimes installed in pipelines from gas wells, is another name for natural-gas condensate, a naturally occurring form of gasoline obtained as a byproduct of natural gas extraction. It is also known as "condensate", "natural gasoline", "casing head gas", "raw gas", "white gas" and "liquid gold". Drip gas is defined in the United States Code of Federal Regulations as consisting of butane, pentane, and hexane hydrocarbons. Within set ranges of distillation, drip gas may be extracted and used to denature fuel alcohol.
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Stable carbenes are readily soluble in non-polar solvents such as hexane, and so typically recrystallisation of stable carbenes can be difficult, due to the unavailability of suitable non-acidic polar solvents. Air-free sublimation as shown right can be an effective method of purification, although temperatures below 60 °C under high vacuum are preferable as these carbenes are relatively volatile and also could begin to decompose at these higher temperatures. Indeed, sublimation in some cases can give single crystals suitable for X-ray analysis. However, strong complexation to metal ions like lithium will in most cases prevent sublimation.
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Oil of Bixa orellana Before synthetic dyes revolutionized industry, Bixa orellana was planted commercially for its pigment, extracted from the pericarp of the seeds first by grinding the seeds and then extracting the pigment through use of enzymes, solvents or oil (corn oil or soybean oil). Solvents include alkaline solutions like sodium hydroxide or potassium hydroxide, as well as organic solvents including hexane, acetone, chloroform and ethanol. Extractions using organic solvent yield the annatto pigment. The annatto pigment has global economic significance as it is one of the most widely used natural dyes to color food, cosmetics and pharmaceutical products.
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NaK containing 40% to 90% potassium by weight is liquid at room temperature. The eutectic mixture consists of 77% potassium and 23% sodium, is liquid from , and has a density of 866 kg/m3 at and 855 kg/m3 at , making it less dense than water. It is highly reactive with water and is stored usually under hexane or other hydrocarbons, or under an inert gas (usually dry nitrogen or argon) if high purity and low levels of oxidation are required. NaK has a very high surface tension, which makes large amounts of it pull into a bun-like shape.
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1,1,1-Trichloroethane is generally considered a non-polar solvent. Owing to the good polarizability of the chlorine atoms, it is a superior solvent for organic compounds that do not dissolve well in hydrocarbons such as hexane. It is an excellent solvent for many organic materials and also one of the least toxic of the chlorinated hydrocarbons. Prior to the Montreal Protocol, it was widely used for cleaning metal parts and circuit boards, as a photoresist solvent in the electronics industry, as an aerosol propellant, as a cutting fluid additive, and as a solvent for inks, paints, adhesives, and other coatings.
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Stock and Somieski completed the hydrolysis of dichlorosilane by putting the solution of H2SiCl2 in benzene in brief contact with a large excess of water.Seyferth D., Prud’Homme C., Linear Polysiloxanes from Dichlorosilane, Inorganic Chemistry, 23, 4412-4417 A large-scale hydrolysis was done in a mixed ether/alkane solvent system at 0 °C, which gave a mixture of volatile and nonvolatile [H2SiO]n. Fischer and Kiegsmann attempted the hydrolysis of dichlorosilane in hexane, using NiCl2⋅6H2O as the water source, but the system failed. They did, however, complete the hydrolysis using dilute Et2O/CCl4 at -10 °C.
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Paprika oleoresin (also known as paprika extract and oleoresin paprika) is an oil-soluble extract from the fruits of Capsicum annuum or Capsicum frutescens, and is primarily used as a colouring and/or flavouring in food products. It is composed of vegetable oil (often in the range of 97% to 98%), capsaicin, the main flavouring compound giving pungency in higher concentrations, and capsanthin and capsorubin, the main colouring compounds (among other carotenoids). It is much milder than capsicum oleoresin, often containing no capsaicin at all. Extraction is performed by percolation with a variety of solvents, primarily hexane, which are removed prior to use.
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Supercritical carbon dioxide is used to remove organochloride pesticides and metals from agricultural crops without adulterating the desired constituents from the plant matter in the herbal supplement industry.Department of Pharmaceutical Analysis, Shenyang Pharmaceutical University, Shenyang 110016, China Supercritical carbon dioxide can be used as a more environmentally friendly solvent for dry cleaning over traditional solvents such as hydrocarbons, including perchloroethylene. Supercritical carbon dioxide is used as the extraction solvent for creation of essential oils and other herbal distillates. Its main advantages over solvents such as hexane and acetone in this process are that it is non-toxic and non- flammable.
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The canister on the left is whipped cream, a product which is pressurized with nitrous oxide. Glue and gasoline (petrol) sniffing is also a problem in parts of Africa, especially with street children. In India and South Asia, three of the most widely abused inhalants are the Dendrite brand and other forms of contact adhesives and rubber cements manufactured in Kolkata, and toluenes in paint thinners. Genkem is a brand of glue which had become the generic name for all the glues used by glue-sniffing children in Africa before the manufacturer replaced n-hexane in its ingredients in 2000.
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Vacuum evaporators as a class function because lowering the pressure above a bulk liquid lowers the boiling points of the component liquids in it. Generally, the component liquids of interest in applications of rotary evaporation are research solvents that one desires to remove from a sample after an extraction, such as following a natural product isolation or a step in an organic synthesis. Liquid solvents can be removed without excessive heating of what are often complex and sensitive solvent- solute combinations. Rotary evaporation is most often and conveniently applied to separate "low boiling" solvents such a n-hexane or ethyl acetate from compounds which are solid at room temperature and pressure.
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It is a common observation that when oil and water are poured into the same container, they separate into two phases or layers, because they are immiscible. In general, aqueous (or water-based) solutions, being polar, are immiscible with non-polar organic solvents (chloroform, toluene, hexane etc.) and form a two- phase system. However, in an ABS, both immiscible components are water-based. The formation of the distinct phases is affected by the pH, temperature and ionic strength of the two components, and separation occurs when the amount of a polymer present exceeds a certain limiting concentration (which is determined by the above factors).
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Normal phase elution is achieved by pumping the non-aqueous or phase of a biphasic solvent system through the column as the mobile phase, with a more polar stationary phase being retained in the column. The cause of original nomenclature of is relevant. As original stationary phases of paper chromatography were superseded by more efficient materials such as diatomaceous earths (natural micro-porous silica) and followed by modern silica gel, the thin-layer chromatography stationary phase was polar (hydroxy groups attached to silica) and maximum retention was achieved with non-polar solvents such as n-hexane. Progressively more polar eluents were then used to move polar compounds up the plate.
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Ph3PO is a byproduct of many useful reactions in organic synthesis including the Wittig, Staudinger, and Mitsunobu reactions. It is also formed when PPh3Cl2 is employed to convert alcohols into alkyl chlorides: :Ph3PCl2 \+ ROH -> Ph3PO + HCl + RCl Triphenylphosphine can be regenerated from the oxide by treatment with a variety of deoxygenation agents, such as phosgene or trichlorosilane/triethylamine: :Ph3PO + SiHCl3 -> PPh3 \+ 1/n (OSiCl2)n \+ HCl Triphenylphosphine oxide can be difficult to remove from reaction mixtures by means of chromatography. It is poorly soluble in hexane and cold diethyl ether. Trituration or chromatography of crude products with these solvents often leads to a good separation of triphenylphosphine oxide.
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Facility records indicate that the following materials were stored in tanks: methanol, ethanol, xylene, propylene glycol, 2-ethoxyethyl acetate, isopropyl acetate, isophorone, ethyl acetate, butanol, kerosene, tolusol, hexane, ispropanol, 2-butanone, 2-butoxy ethanol, toluene, acetone, and unleaded gasoline. These compounds can have health effects on infants or very young children. It has been reported that "respiratory, allergic, or immune effects in infants or children" are associated with indoor VOCs and other indoor air pollutants. It is suggested that VOC particles in an indoor environment can be reduced by 50% when household rugs and carpets are cleaned with efficient vacuum cleaners and hot water.
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Studies of successful decarboxylation over nickel and palladium based catalysts were first reported by Wilhelm Maier et al. in 1982. These authors achieved the deoxygenation of several carboxylic acids via decarboxylation under a hydrogen atmosphere – including the conversion of aliphatic acids (such as heptanoic and octanoic acids) to alkanes (namely hexane and heptane) – a reaction in which Pd catalysts afforded the best results (close to quantitative yields). This reaction can be written as: RCO2H → RH + CO2 In 2006, Dmitry Murzin produced a patent with Neste Oil to manufacture hydrocarbons in the diesel fuel range from renewable feedstock with decreased consumption of hydrogen using Group VIII metals.
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Core chemical structure of a bis-triazinyl bipyridine The bis-triazinyl bipyridines (BTBPs) are a class of chemical compounds which are tetradentate ligands similar in shape to quaterpyridine. The BTBPs are made by the reaction of hydrazine and a 1,2-diketone (such as hexane-3,4-dione) with 6,6'-dicyano-2,2'-bipyridine. The dicyanobipy can be made by reacting 2,2'-bipy with hydrogen peroxide in acetic acid, (followed by the addition of acetone) to form 2,2'-bipyridine-N,N-dioxide. The 2,2'-bipyridine-N,N-dioxide is then converted into the dicyano compound by treatment with potassium cyanide and benzoyl chloride in a mixture of water and THF.
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Occupational Safety and Health Guideline for n-Hexane , Occupational Safety and Health Administration (OSHA). A 2014 BBC investigation found excessive hours and other problems persisted, despite Apple's promise to reform factory practice after the 2010 Foxconn suicides. The Pegatron factory was once again the subject of review, as reporters gained access to the working conditions inside through recruitment as employees. While the BBC maintained that the experiences of its reporters showed that labor violations were continuing since 2010, Apple publicly disagreed with the BBC and stated: "We are aware of no other company doing as much as Apple to ensure fair and safe working conditions".
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The adjacent diagram illustrates total vapor pressure of three hypothetical mixtures of constituents, X, and Y. The temperature throughout the plot is assumed to be constant. The center trace is a straight line, which is what Raoult's law predicts for an ideal mixture. In general solely mixtures of chemically similar solvents, such as n-hexane with n-heptane, form nearly ideal mixtures that come close to obeying Raoult's law. The top trace illustrates a nonideal mixture that has a positive deviation from Raoult's law, where the total combined vapor pressure of constituents, X and Y, is greater than what is predicted by Raoult's law.
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Workers who assemble iPhones, iPads, and other devices often labor under harsh conditions, according to employees inside the Foxconn plants. According to company reports and advocacy, Apple's suppliers in China have improperly disposed of hazardous waste and falsified records. Forty-nine young men and women were poisoned at the Lianjian Technology factory in Suzhou Industrial Park by the toxic chemical hexane, used to wipe clean the iPad display screens and speed up efficiency. To save money, the factory did not provide proper ventilation during the cleaning process, and workers developed neurological problems, the loss of motor function, numb limbs, and complained of constantly fainting and being overcome by a debilitating fatigue.
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In the CCS system, carbon chain lengths are denoted by celestial stems (甲 jiǎ, 乙 yǐ, 丙 bǐng, 丁 dīng, 戊 wù, 己 jǐ, 庚 gēng, 辛 xīn, 壬 rén, 癸 guǐ), characters used since the Shang Dynasty (16th-11th centuries BCE) for naming days (and later, to name years). For example, hexane is 己烷 jǐwán, since 己 jǐ is the sixth celestial stem. Longer carbon chains are specified by number followed by '碳' tàn 'carbon'. For example, 1-hexadecene is 1-十六碳烯 (read as [1, yī] [-, wèi] [十六, shíliù, '16'] [碳, tàn] [烯, xī]), where the hyphen is read as 位 (wèi, 'position').
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Ru(CO)5 was originally prepared by carbonylation of ruthenium salts in the presence of a reducing agent.W. Manchot, Wilhelm J. Manchot "Darstellung von Rutheniumcarbonylen und -nitrosylen" Zeitschrift für Anorganische und Allgemeine Chemie 1936, volume 226, pp. 385-415. A more recent preparation involves photolysis of triruthenium dodecacarbonyl in the presence of carbon monoxide:Adams, R. D.; Barnard, T. S.; Cortopassi, J. E.; Wu, W.; Li, Z. "Platinum-ruthenium carbonyl cluster complexes" Inorganic Syntheses 1998, volume 32, pp. 280-284. :Ru3(CO)12 \+ 3 CO 3 Ru(CO)5 It is characterized by two intense νCO bands in the IR spectrum at 2038 and 2003 cm−1 (hexane solution).
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Some petroleum refineries also produce small amounts of specialty naphthas for use as solvents, cleaning fluids and dry- cleaning agents, paint and varnish diluents, asphalt diluents, rubber industry solvents, recycling products, and cigarette-lighter, portable-camping-stove and lantern fuels. Those specialty naphthas are subjected to various purification processes. Sometimes the specialty naphthas are called petroleum ether, petroleum spirits, mineral spirits, paraffin, benzine, hexane, ligroin, white oil or white gas, painters naphtha, refined solvent naphtha and Varnish makers' & painters' naphtha (VM&P;). The best way to determine the boiling range and other compositional characteristics of any of the specialty naphthas is to read the Safety Data Sheet (SDS) for the specific naphtha of interest.
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Lipophilicity (from Greek λίπος "fat" and φίλος "friendly"), refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non- polar solvents such as hexane or toluene. Such non-polar solvents are themselves lipophilic (translated as "fat-loving" or "fat-liking"Compendium of Chemical Terminology, lipophilic, accessed 15 Jan 2007.), and the axiom that "like dissolves like" generally holds true. Thus lipophilic substances tend to dissolve in other lipophilic substances, but hydrophilic ("water-loving") substances tend to dissolve in water and other hydrophilic substances. Lipophilicity, hydrophobicity, and non-polarity may describe the same tendency towards participation in the London dispersion force, as the terms are often used interchangeably.
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In addition to visual cues, A. paraponerae are also attracted to 4-methyl-3-heptanone and 4-methyl-3-heptanol, which are major products of the mandibular glands of the host ant P. clavata. As these chemicals are released by fighting, injured, and freshly killed workers, A. paraponerae may use these pheromones to locate suitable targets for feeding or egg-laying. In an experiment, A. paraponerae were found to be equally attracted to ants that were treated with hexane, but unwilling to lay eggs on them. This suggests that A. paraponerae is either unwilling or unable to lay eggs on ants lacking the characteristic chemical signals of 4-methyl-3-heptanone and 4-methyl-3-heptanol.
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In a study conducted in 2014 by Jean-Jaques Filippi, Marie Marchini, Céline Charvoz, Laurence Dujourdy and Nicolas Baldovini (Multidimensional analysis of cannabis volatile constituents: Identification of 5,5-dimethyl-1-vinylbicyclo[2.1.1]hexane as a volatile marker of hashish, the resin of Cannabis sativa L.) the researchers linked the characteristic flavour of hashish with a rearrangement of myrcene caused during the process of manufacture.Alchimia Blog, Hashishene, the new terpene of cannabis Depending on the production process, the product can be contaminated with different amounts of dirt and plant fragments, varying greatly in terms of appearance, texture, odour and potency. Also, adulterants may be added in order to increase weight or modify appearance.
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Like most organoaluminum compounds, the compound’s structure is most probably more than that suggested by its empirical formula. A variety of techniques, not including X-ray crystallography, suggest that the compound exists as a dimer and a trimer, consisting of tetrahedral aluminium centers sharing bridging hydride ligands. Hydrides are small and, for aluminium derivatives, are highly basic, thus they bridge in preference to the alkyl groups. DIBAL can be prepared by heating triisobutylaluminium (itself a dimer) to induce beta- hydride elimination: :(i-Bu3Al)2 -> (i-Bu2AlH)2 \+ 2 (CH3)2C=CH2 Although DIBAL can be purchased commercially as a colorless liquid, it is more commonly purchased and dispensed as a solution in an organic solvent such as toluene or hexane.
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Interaction of triethylphosphine oxide with a Lewis acidThe 31P chemical shift (δ) of Et3PO is sensitive to chemical environment but can usually be found between +40 and +100 ppm. The O atom in Et3PO is a Lewis base, and its interaction with Lewis acid sites causes deshielding of the adjacent P atom. Gutmann described an Acceptor Number (AN) scale for solvent Lewis acidity V. Gutmann, "Solvent effects on reactivities of organometallic compounds", Coord. Chem. Rev., 1976, 18, 225–255. doi: 10.1016/S0010-8545(00)82045-7 with two reference points relating to the 31P NMR chemical shift of Et3PO in the weakly Lewis acidic solvent hexane (δ = 41.0 ppm, AN 0) and in the strongly Lewis acidic solvent SbCl5 (δ = 86.1 ppm, AN 100).
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The mode known a pH-zone- refining is a type of ion-exchange mode that utilizes acids and/or bases as solvent modifiers. Typically, the analytes are eluted in an order determined by their pKa values. For example, 6 oxindole alkaloids were isolated from a 4.5g sample of Gelsemium elegans stem extract with a biphasic solvent system composed of hexane–ethyl acetate–methanol–water (3:7:1:9, v/v) where 10 mM triethylamine (TEA) was added to the upper organic stationary phase as a retainer and 10 mM hydrochloric acid (HCl) to the aqueous mobile phase as an eluter. Ion-exchange modes such as pH-zone-refining have tremendous potential because high sample loads can be achieved without sacrificing separation power.
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The trimer has also found applications in research by enabling aromatic coupling reactions between pyridine and either N,N-dialkylanilines or indole, resulting in 4,4'-substituted phenylpyridine derivatives, postulated to go through a cyclophosphazene pyridinium salt intermediate. The compound may also be used as a peptide coupling reagent for the synthesis of oligopeptides in chloroform, though for this application the tetramer octachlorotetraphosphazene usually proves more effective. Finally, both the trimer and tetramer may photochemically react when dissolved in hexane, decaline, benzene or toluene, forming clear liquids identified as alkyl- substituted at P derivatives of the form (NPCl2-xRx)n=3,4. Such reactions proceed under prolonged UVC (mercury arc) illumination, yet the cyclophosphazene rings are not affected, a testiment of their notable chemical stability.
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From antimony trichloride and tris(trimethylsilyl)amine, a nitridoantimone cubane-type cluster can be formed almost quantitatively at –60 °C. Ketones can be trifluoromethylated in the presence of P4-t-Bu and nonamethyltrisilazane under mild conditions in yields of up to 84% with the inert fluoroform (HCF3, HFC-23). The monomer trichloro(trimethylsilyl)-phosphoranimine Cl3P=NSiMe3 is formed from tris(trimethylsilyl)amine and phosphorus pentachloride in hexane at 0 °C, Synthese von Trichlor(trimethylsilyl)phosphoranimin which can be polymerized to linear polydichlorophosphazenes with defined molecular weights and polydispersities. The cyclic trimer (NPCl2)3 hexachlorocyclotriphosphane is predominantly formed from tris(trimethylsilyl)amine and phosphorus pentachloride in boiling dichloromethane (about 40 °C) among other oligomers which gives upon heating over 250 °C high molecular weight, little defined polydichlorophosphazenes.
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Together they define the critical point of a fluid above which distinct liquid and gas phases of a given fluid do not exist. The pressure-volume-temperature (PVT) data for real gases varies from one pure gas to another. However, when the compressibility factors of various single-component gases are graphed versus pressure along with temperature isotherms many of the graphs exhibit similar isotherm shapes. In order to obtain a generalized graph that can be used for many different gases, the reduced pressure and temperature, P_r and T_r, are used to normalize the compressibility factor data. Figure 2 is an example of a generalized compressibility factor graph derived from hundreds of experimental PVT data points of 10 pure gases, namely methane, ethane, ethylene, propane, n-butane, i-pentane, n-hexane, nitrogen, carbon dioxide and steam.
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The industrial synthesis of alkylated ketenedimers (at that time still called ketoethenones) was patented in 1945 from long-chain carboxylic acid chlorides in inert solvents (such as diethyl ether or benzene) with triethylamine as tertiary amine under anhydrous conditions. After filtration of the insoluble triethylamine hydrochloride and evaporation of the solvent, long-chain alkyl chain dimers are obtained in yields of more than 90%. Synthese von C18-AKD aus Stearoylchlorid The use of other solvents, such as carboxylic acid esters or ketones for easier separation of trialkylamine hydrochlorides or other amines, such as N,N,N',N'-tetramethyl-hexane-1,6-diamine does not provide any significant advantages. Also processes without the solvent use are described, in which the resulting amine hydrochloride is either filtered off or extracted with diluted aqueous acids.
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Intel has been accused by some residents of Rio Rancho, New Mexico of allowing VOCs to be released in excess of their pollution permit. One resident claimed that a release of 1.4 tons of carbon tetrachloride was measured from one acid scrubber during the fourth quarter of 2003 but an emission factor allowed Intel to report no carbon tetrachloride emissions for all of 2003. Another resident alleges that Intel was responsible for the release of other VOCs from their Rio Rancho site and that a necropsy of lung tissue from two deceased dogs in the area indicated trace amounts of toluene, hexane, ethylbenzene, and xylene isomers,Corrales Comment 11/25/2006 Intel Pollution Unresolved. all of which are solvents used in industrial settings but also commonly found in gasoline, retail paint thinners and retail solvents.
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In most countries, a separate definition of VOCs is used with regard to indoor air quality that comprises each organic chemical compound that can be measured as follows: adsorption from air on Tenax TA, thermal desorption, gas chromatographic separation over a 100% nonpolar column (dimethylpolysiloxane). VOC (volatile organic compounds) are all compounds that appear in the gas chromatogram between and including n-hexane and n-hexadecane. Compounds appearing earlier are called VVOC (very volatile organic compounds); compounds appearing later are called SVOC (semi-volatile organic compounds). France, Germany, and Belgium have enacted regulations to limit VOC emissions from commercial products, and industry has developed numerous voluntary ecolabels and rating systems, such as EMICODE, M1, Blue Angel and Indoor Air Comfort In the United States, several standards exist; California Standard CDPH Section 01350 is the most common one.
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The size of the porogen particles will affect the size of the scaffold pores, while the polymer to porogen ratio is directly correlated to the amount of porosity of the final structure. After the polymer solution has been cast the solvent is allowed to fully evaporate, then the composite structure in the mold is immersed in a bath of a liquid suitable for dissolving the porogen: water in the case of sodium chloride, saccharose and gelatin or an aliphatic solvent like hexane for use with paraffin. Once the porogen has been fully dissolved, a porous structure is obtained. Other than the small thickness range that can be obtained, another drawback of SCPL lies in its use of organic solvents which must be fully removed to avoid any possible damage to the cells seeded on the scaffold.
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Granadaene contains a conjugated system made up of a linear chain of 12 conjugated double bonds which is connected to the amino acid ornithine at one end and the sugar rhamnose at the other. Granadaene is dark red, odorless, insoluble in water, methanol, ethanol, diethyl ether, acetone, hexane, dimethyl sulfoxide (DMSO), acetonitrile, tetrahydrofuran, chloroform, and in most solvents, it is soluble in DMSO–0.1% trifluoroacetic acid (TFA). Granadaene, can be extracted from cultures of S.agalactiae in granada broth (granada medium without agar) with 0.1 M potassium hydroxide (KOH) and purified by size-exclusion chromatography on Sephadex LH using DMSO–0.1%TFA. Streptococcus agalactiae in granada broth Ultraviolet/visible spectrum of granadaene, in DMSO+TFA Proposed metabolic pathway for granadaene biosynthesis The ultraviolet-visible absorption spectrum of the granadaene (in DMSO/TFA) is almost identical to that of a carotene with a similar conjugated system of double bonds (e.g.
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The Jeffrey pine is noted for producing exceptionally high levels of n-heptane in its resin, for which reason its distillate was designated as the zero point for one octane rating. Floral scents have also long been known to contain volatile alkane components, and n-nonane is a significant component in the scent of some roses. Emission of gaseous and volatile alkanes such as ethane, pentane, and hexane by plants has also been documented at low levels, though they are not generally considered to be a major component of biogenic air pollution. Edible vegetable oils also typically contain small fractions of biogenic alkanes with a wide spectrum of carbon numbers, mainly 8 to 35, usually peaking in the low to upper 20s, with concentrations up to dozens of milligrams per kilogram (parts per million by weight) and sometimes over a hundred for the total alkane fraction.
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Hydrated iron(III) chloride (ferric chloride) The binary ferrous and ferric halides are well-known. The ferrous halides typically arise from treating iron metal with the corresponding hydrohalic acid to give the corresponding hydrated salts. :Fe + 2 HX → FeX2 \+ H2 (X = F, Cl, Br, I) Iron reacts with fluorine, chlorine, and bromine to give the corresponding ferric halides, ferric chloride being the most common. :2 Fe + 3 X2 → 2 FeX3 (X = F, Cl, Br) Ferric iodide is an exception, being thermodynamically unstable due to the oxidizing power of Fe3+ and the high reducing power of I−: :2 I− \+ 2 Fe3+ → I2 \+ 2 Fe2+ (E0 = +0.23 V) Ferric iodide, a black solid, is not stable in ordinary conditions, but can be prepared through the reaction of iron pentacarbonyl with iodine and carbon monoxide in the presence of hexane and light at the temperature of −20 °C, with oxygen and water excluded.
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Using high octane gasoline fuel in a vehicle that does not need it is generally considered an unnecessary expense, although Toyota has measured slight differences in efficiency due to octane number even when knock is not an issue. All vehicles in the United States built since 1996 are equipped with OBD-II on-board diagnostics and most models will have knock sensors that will automatically adjust the timing if and when pinging is detected, so low octane fuel can be used in an engine designed for high octane, with some reduction in efficiency and performance. If the engine is designed for high octane then higher octane fuel will result in higher efficiency and performance under certain load and mixture conditions. The energy released during combustion of hydrocarbon fuel increases as the molecule chain length decreases, so gasoline fuels with higher ratios of the shorter chain alkanes such as heptane, hexane, pentane, etc.
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In the United States, the hydrocarbon dew point of processed, pipelined natural gas is related to and characterized by the term GPM which is the gallons of liquefiable hydrocarbons contained in of natural gas at a stated temperature and pressure. When the liquefiable hydrocarbons are characterized as being hexane or higher molecular weight components, they are reported as GPM (C6+).White Paper on Liquid Hydrocarbon Drop Out in Natural Gas Infrastructure (NGC+ Liquid Hydrocarbon Dropout Task Group, October 15, 2004)White Paper on Liquid Hydrocarbon Drop Out in Natural Gas Infrastructure (NGC+ Liquid Hydrocarbon Dropout Task Group, September 28, 2005) However, the quality of raw produced natural gas is also often characterized by the term GPM meaning the gallons of liquefiable hydrocarbons contained in of the raw natural gas. In such cases, when the liquefiable hydrocarbons in the raw natural gas are characterized as being ethane or higher molecular weight components, they are reported as GPM (C2+).
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In addition to its use for powering aircraft, JP-8 is used as a fuel for heaters, stoves,Modern Burner Units , JP-8 is used by Army Food Service Specialists (cooks) to fuel MBUs, in accordance with U.S. Army Field Feeding Manual FM 10-23Babington Airtronic Burner burns JP-8 and other distillate fuels, and is the current common heat source for Marine Corps food service equipment. tanks,the M1 Abrams series of battle tanks uses JP fuel in its gas turbine engine by the U.S. military and its NATO allies as a replacement for diesel fuel in the engines of nearly all tactical ground vehicles and electrical generators, and as a coolant in engines and some other aircraft components. The use of a single fuel greatly simplifies logistics. JP-8 is formulated with an icing inhibitor, corrosion inhibitors, lubricants, and antistatic agents, and less benzene (a carcinogen) and less n-hexane (a neurotoxin) than JP-4.
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Antimicrobial screening of Chungtia medicinal plants used customarily for skin related ailments, i.e. Albizia lucidior (roots), Begonia picta (leaves), Cassia floribunda (leaves), Holboellia latifolia (leaves), Maesa indica (leaves) and Prunus persica (roots) against dermatologically relevant microorganisms showed that all of the plants possess various levels of antibacterial activity. This supports the customary use of these species. Investigation of the n-hexane and EtOAc fractions of the root extract of P. persica using bioassay-guided isolation techniques led to the isolation of ent-epiafzelechin-(2α→O→7’,4α→8’)-(-)ent- afzelechin (1, S. aureus MIC 156 µg/mL, MRSA and MDRSA MIC 312 µg/mL, E. coli β-, S. typhimurium and P. aeruginosa MIC 2500 µg/mL), afzelechin (2, not active), α-cyanobenzyl benzoate (3, S. aureus, MDRSA and MRSA 78 µg/mL, E. coli β- MIC 312 µg/mL and P. aeruginosa MIC 625 µg/mL), β-sitosterol (4, S. aureus, MDRSA, MRSA and E. coli β- MIC 2500 µg/mL, S. typhimurium MIC 625 µg/mL, P. aeruginosa MIC 1250 µg/mL) and stigmast-4-en-3-one (5, S. aureus, MDRSA and MRSA MIC 156 µg/mL, E. coli β- MIC 312, S. typhimurium MIC 625 µg/mL and P. aeruginosa MIC 1250 µg/mL).
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