Xanthation increases the coal functional groups content for complexing metals.
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TEOA is now commonly and very effectively used as a complexing agent in electroless plating.
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SLC3A2 has been shown to interact with SLC7A7. Additionally, SLC3A2 is a constituent member of the system xc- cystine/glutamate antiporter, complexing with SLC7A11.
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There are three primary chemicals used as the complexing agents.: either cyanide, or sulfuric acid, or pyrophosphate. In addition fluoroborate, and proprietary mixtures are used.
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Fast Sulphon Black is purple when complexed with copper, and turns green when titrated against EDTA, as the EDTA displaces it, being the better complexing agent due to the chelate effect.
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SIRs can be reused for different separation tasks by just rinsing one complexing agent out and re-impregnating them with another more suitable extractant. This way, potentially expensive design and production steps of e.g. affinity resins can be avoided. Finally, by filling the whole volume of the particle pores with an extractant (complexing agent), a higher capacity for solutes can be achieved than with ordinary adsorption or ion exchange resins, where only the surface area is available.
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Ammonium bifluoride is also used as an additive in tin-nickel plating processes as the fluoride ion acts as a complexing agent with the tin, allowing for greater control over the resulting composition and finish.
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N-(2-carboxyethyl)iminodiacetic acid or β-ADA (β-alanine diacetate) is a tetradentate complexing agent which forms stable 1:1 chelate complexes with cations having a charge number of at least +2, e.g. the "hard water forming" cations Ca2+ or Mg2+. N-(2-Carboxyethyl)iminodiacetic acid should not be confused with α-Alaninediacetic acid, also known as methylglycinediacetic acid (MGDA) or α-ADA. Alkaline earth and heavy metal complexes of both, α-ADA and β-ADA are biodegradable (in contrast to chelate complexes with conventional complexing agents such as EDTA).
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Oxalic acid's main applications include cleaning or bleaching, especially for the removal of rust (iron complexing agent). Its utility in rust removal agents is due to its forming a stable, water-soluble salt with ferric iron, ferrioxalate ion.
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1,8-Diazabicyclo[5.4.0]undec-7-ene, or more commonly DBU, is a chemical compound and belongs to the class of amidine compounds. It is used in organic synthesis as a catalyst, a complexing ligand, and a non-nucleophilic base.
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To further reduce self-discharge and to reduce the vapor pressure of bromine, complexing agents are added to the positive electrolyte. These react reversibly with the bromine to form an oily red liquid and reduce the concentration in the electrolyte.
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Nitrilotriacetonitrile (NTAN) is a precursor for nitrilotriacetic acid (NTA, a biodegradable complexing agent and building block for detergents), for tris(2-aminoethyl)amine (a tripodal tetradentate chelating agent known under the abbreviation tren) and for the epoxy resin crosslinker aminoethylpiperazine.
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DOTA (also known as tetraxetan) is an organic compound with the formula (CH2CH2NCH2CO2H)4. The molecule consists of a central 12-membered tetraaza (i.e., containing four nitrogen atoms) ring. DOTA is used as a complexing agent, especially for lanthanide ions.
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They exhibit high hydrophilicity, biocompatibility, and complexing ability. When used as a blend of PVA/PVP hydrogel, they produced similar internal 3D structure and water content as natural articular cartilage. The best mechanical properties and friction system were blended hydrogel with 1 wt. % PVP.
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The increased binding arises from the formation of a 2:1 complex, with two cyanostars sandwiching the anion on each side. An extended version of this structural pattern is a 4:3 alternating stack of cyanostar molecules complexing a hydrogen-bonded chain of dihydrogen phosphate units.
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František Mikeš, Geraldine Boshart, and Emanuel Gil-Av (1976): "Helicenes. Resolution on chiral charge-transfer complexing agents using high performance liquid chromatography". Journal of the Chemical Society, Chemical Communications, volume 1976, issue 3, pages 99-100. These non-planar forms are chiral, and their enantiomers can be isolated.
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Upon crystallization, molecular or polymeric compounds can be isolated. Dissolution is also observed when a solution of the appropriate complexing agent in acetone or chloroform is used. For example, thiourea and its derivatives can be used. Solids that crystallize out of those solutions are composed of hybrid inorganic chains.
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Large quantities of the antivenom must be injected to counter the effects of the venom. The polyvalent antivenin is produced by injecting horses with adapted venom. The venom is first detoxified to prevent too much damage and death. This is mostly done by complexing the venom with an aldehyde like formalin.
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The acid has been observed to chelate metal ions such as calcium and magnesium. Therefore, the acid has served in the farming and metal industries as a chelating agent for complexing micronutrients in soil fertilizer and for cleaning metal surfaces consisting of aluminium, copper, iron, and alloys of these metals, respectively.
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In addition, the development of SPEs has enable the reduction of the production costs. One of the principal advantages is the possibility of modifying the screen-printed electrodes, modifying the composition of its inks by adding different metals, enzymes, complexing agents, polymers, etc., which is useful for the preparation of multitude electrochemical analyses.
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Analogous to 18-crown-6, 15-crown-5 binds to sodium ions. Thus, when treated with this complexing agent, sodium salts often become soluble in organic solvents. First-row transition metal dications fit snugly inside the cavity of 15-crown-5. They are too small to be included in 18-crown-6.
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Its ion-complexing capability allows beauvericin to transport alkaline earth metal and alkali metal ions across cell membranes. Beauvericin has in vitro fungicidal effects on Candida parapsilosis when used in combination with the antifungal drug ketoconazole at dosages of 0.1 μg/ml. Increased survivability rates and low cytotoxicity were also observed in mouse models.
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In this process, rare- earth ions are sorbed onto suitable ion-exchange resin by exchange with hydrogen, ammonium or cupric ions present in the resin. The rare earth ions are then selectively washed out by suitable complexing agent. Erbium metal is obtained from its oxide or salts by heating with calcium at under argon atmosphere.
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Like thallium, moscovium should have a common +1 oxidation state and a less common +3 oxidation state, although their relative stabilities may change depending on the complexing ligands or the degree of hydrolysis. Moscovium(I) oxide (Mc2O) should be quite basic, like that of thallium, while moscovium(III) oxide (Mc2O3) should be amphoteric, like that of bismuth.
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1,1,1,3,3,3-Hexafluoroisopropylbis(pentafluorophenyl)borinate can greatly increase solubility of LiF by complexing the F− anion. This has potential to improve lithium batteries. Borinic esters are being researched as bacterial growth inhibitors due to their ability to disable some bacterial enzymes such as menaquinone methyltransferase and CcrM. This may result in development of treatments for topical application on skin.
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Several rare earth metals, including lutetium, are separated as a double salt with ammonium nitrate by crystallization. Lutetium is separated by ion exchange. In this process, rare- earth ions are sorbed onto suitable ion-exchange resin by exchange with hydrogen, ammonium or cupric ions present in the resin. Lutetium salts are then selectively washed out by suitable complexing agent.
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With more intelligent encoders, GOP size is dynamically chosen, up to some pre-selected maximum limit. Limits are placed on the maximum number of frames between I-frames due to decoding complexing, decoder buffer size, recovery time after data errors, seeking ability, and accumulation of IDCT errors in low-precision implementations most common in hardware decoders (See: IEEE-1180).
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Another common use of TEOA is as a complexing agent for aluminium ions in aqueous solutions. This reaction is often used to mask such ions before complexometric titrations with another chelating agent such as EDTA. TEOA has also been used in photographic (silver halide) processing. It has been promoted as a useful alkali by amateur photographers.
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The most efficient separation routine for holmium oxide from the rare- earths is ion exchange. In this process, rare-earth ions are adsorbed onto suitable ion-exchange resin by exchange with hydrogen, ammonium or cupric ions present in the resin. The rare earth ions are then selectively washed out by suitable complexing agent, such as ammonium citrate or nitrilotriacetate.
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Upon complexing with plasma membrane associated phosphatase Psr1, Whi2 induces general stress response by dephosphorylating general stress response transcription factor Msn2. Whi2 is essential for Msn2 activity, moreover activation by Whi2 is dominant and independent of the PKA and TOR activation pathways. Additionally, experiments are suggesting Whi2 for playing a role in Ras2 deactivation or degradation during nutrient depletion.
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Borax as a source of borate has been used to take advantage of the co-complexing ability of borate with other agents in water to form complex ions with various substances. Borate and a suitable polymer bed are used to chromatograph non-glycosylated hemoglobin differentially from glycosylated hemoglobin (chiefly HbA1c), which is an indicator of long-term hyperglycemia in diabetes mellitus.
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Both amines affect the regiochemistry of metalation. In the PMDTA/n-BuLi adducts, the Li-C bonds are highly polarized, thus increasing the basicity of the butyl group. The effect of PMDTA on lithium anilide is illustrative of PMDTA's complexing power. The complex, [{PhN(H)Li}3·2PMDTA], is trinuclear, featuring approximately colinear Li+ centers that are three-, four-, and five- coordinate.
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Screening studies on FDCA-derived anilides showed their important anti-bacterial action. The diacid itself is a strong complexing agent, chelating such ions as: Ca2+, Cu2+ and Pb2+; it is utilized in medicine to remove kidney stones. HMF is metabolized via FDCA in mammals including humans. A very diluted solution of FDCA in tetrahydrofuran is utilized for preparing artificial veins for transplantation.
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Poisonous compounds may be useful either for their toxicity, or, more often, because of another chemical property, such as specific chemical reactivity. Poisons are widely used in industry and agriculture, as chemical reagents, solvents or complexing reagents, e.g. carbon monoxide, methanol and sodium cyanide, respectively. They are less common in household use, with occasional exceptions such as ammonia and methanol.
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Characteristically the organic substituents are branched to confer solubility and preclude crystallization. The dithiodialkyphosphinic acids (R2PS2H) are related to the diorganodithiophosphates with the formula (RO)2PS2H, which are also used as complexing agents in the purification of metals. The phosphates are more prone to hydrolysis owing to the greater lability of the RO-P linkage vs the direct C-P bond.
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National Council for Science and the Environment. Washington DC They are good complexing agents for metal ions (such as calcium and many transition metals) and have many uses in industrial chemistry. Pyrophosphate is the first member of an entire series of polyphosphates. The term pyrophosphate is also the name of esters formed by the condensation of a phosphorylated biological compound with inorganic phosphate, as for dimethylallyl pyrophosphate.
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Dipeptidyl peptidase-4 (DPP4), also known as adenosine deaminase complexing protein 2 or CD26 (cluster of differentiation 26) is a protein that, in humans, is encoded by the DPP4 gene. DPP4 is related to FAP, DPP8, and DPP9. The enzyme was discovered in 1966 by Hopsu-Havu and Glenner, and as a result of various studies on chemism, was called dipeptidyl peptidase IV [DP IV].
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This provides cellular release of hydrogen peroxide, which is an immune modulator. The respiratory burst uses peroxide to form hypochlorite, which in turn destroys bacteria. The mechanism of action against cancer cells is not fully understood. It may be a result of the different earlier mentioned molecular interactions, as complexing with cholesterol, potentiation of the immune system and direct destruction by disruption of the cell membranes.
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Another example of a metal complexing to natural nucleobases is the formation of A-Zn-T and G-Zn-C at high pH; Co+2 and Ni+2 also form these complexes. These are Watson-Crick base pairs where the divalent cation in coordinated to the nucleobases. The exact binding is debated. A large variety of artificial nucleobases have been developed for use as metal base pairs.
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These follow the strengths of the corresponding acids. The divalent ligands are more strongly complexing than the monovalent ones. can also form the complex ions [] (M = Al, Ga, Sc, In, Fe, Cr, Rh) in perchloric acid solution: the strength of interaction between the two cations follows the order Fe > In > Sc > Ga > Al. The neptunyl and uranyl ions can also form a complex together.
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In host–guest chemistry the bistable states of molecular switches differ in their affinity for guests. Many early examples of such systems are based on crown ether chemistry. The first switchable host is described in 1978 by Desvergne & Bouas-LaurentCation complexing photochromic materials involving bisanthracenes linked by a polyether chain. Preparation of a crown-ether by photocycloisomerization Jean-Pierre Desvergne and Henri Bouas-Laurent J. Chem. Soc.
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Both DMPS and DMSA increase the urinary excretion of copper and zinc, which in some patients may give deficiency symptoms. Based on experimental studies and clinical experience Aaseth recommend DMSA to be used against mercury and lead intoxications,Aaseth J, Friedheim EA (1978). Treatment of methyl mercury poisoning in mice with 2, 3‐dimercaptosuccinic acid and other complexing thiols. Acta pharmacologica et toxicologica, 42(4), 248-252.
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TIM14 is required for the ATP-dependent import of mitochondrial pre-proteins into the mitochondrial matrix. The J-domain of TIM14 stimulates mtHsp70 ATPase activity to power this transport. Additionally, TIM14 helps regulate mitochondrial morphology by complexing with prohibitins to perform disphosphoglycerolipid cardiolipin (CL) remodeling. CL is a key phospholipid in mitochondrial membranes that modulates the fusion and fission of mitochondrial membranes, as well as mitophagy and apoptosis.
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Synthese von Nitrilotracetamid (und 3,5-Dioxopiperazin-1-acetamid) Nitrilotriacetonitrile serves mainly as a raw material for the production of the biodegradable, but carcinogen suspected complexing agent nitrilotriacetic acid by acid or base- catalyzed hydrolysis of the cyano groups. Alkalische Hydrolyse von NTAN zu NTA-trinatriumsalz Undesirable residual contents of cyanide ions in the hydrolyzate can be removed by post-treatment with oxidizing agents such as sodium hypochlorite at pH 8.
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Gold(I) complexes are 2-coordinate, linear, diamagnetic, 14 electron species. They typically exist as adducts LAuR with as ligand L for instance a triphenylphosphine or an isocyanide. The ligand prevents reduction of Au(I) to metallic Au(0) with dimerization of the organic residue. Gold(I) can also exist as the aurate M[AuR2] (the ate complex) whereby the cation is usually fitted with a complexing agent to improve stability.
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Since then, several other Mg salts, less corrosive than chloride, have been reported. One drawback compared to lithium is magnesium's higher charge (+2) in solution, which tends to result in increased viscosity and reduced mobility in the electrolyte. In solution a number of species may exist depending on counter ions/complexing agents – these often include singly charged species (e.g. MgCl+ in the presence of chloride) – though dimers are often formed (e.g.
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Histone acetyltransferase KAT7 is an enzyme that in humans is encoded by the KAT7 gene. It specifically acetylates H4 histones at the lysine12 residue (H4K12) and is necessary for origin licensing and DNA replication. KAT7 associates with origins of replication during G1 phase of the cell cycle through complexing with CDT1. Geminin is thought to inhibit the acetyltransferase activity of KAT7 when KAT7 and CDT1 are complexed together.
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As a glycogen phosphorylase, GPBB catalyzes the phosphorolysis of glycogen to yield glucose 1-phosphate. This reaction serves as the rate-determining first step in glycogenolysis and, thus, contributes to the regulation of carbohydrate metabolism. In particular, GPBB is responsible for supplying emergency glucose during periods of stress, including anoxia, hypoglycemia, or ischemia. In normal cell conditions, GPBB is bound to the sarcoplasmic reticulum (SR) membrane by complexing with glycogen.
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Like other complexing agents from the class of aminopolycarboxylic acids, N-(2-carboxyethyl)iminodiacetic acid is used in water softening, in detergents and cleaning agents, in electroplating, cosmetics, paper and textile production. This is based on its ability to form stable chelate complexes with polyvalent ions, in particular the water hardness formers Ca2+ and Mg2+, as well as transition and heavy metal ions, such as Fe3+, Mn2+, Cu2+, etc.
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Although Artemis exhibits 5' → 3' ssDNA exonuclease activity when alone, its complexing with DNA-PKcs allows for endonucleasic processing of the stem-loops. Defects of either protein confers severe immunodeficiency. Homologous recombination, on the other hand, involves two homologous DNA duplexes connected by D-loops or Holliday junctions. In bacteria, endonucleases like RuvC resolve Holliday junctions into two separate dsDNAs by cleaving the junctions at two symmetrical sites near the junction centre.
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As a reagent in organic chemistry, DBU is used as a catalyst, a complexing ligand, and a non-nucleophilic base. It is also used as a curing agent for epoxy. It is used in fullerene purification with trimethylbenzene (it reacts with C70 and higher fullerenes, but not to C60 fullerenes); and it is also used as a catalyst in polyurethane production. It has a strong catalyst effect for the reactions of alicyclic and aliphatic isocyanates.
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In this process, rare-earth ions are sorbed onto suitable ion-exchange resin by exchange with hydrogen, ammonium or cupric ions present in the resin. The rare earth ions are then selectively washed out by suitable complexing agent. As with other rare earths, terbium metal is produced by reducing the anhydrous chloride or fluoride with calcium metal. Calcium and tantalum impurities can be removed by vacuum remelting, distillation, amalgam formation or zone melting.
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Adding another benzene ring to form dibenzo[c,g]phenantrene creates steric hindrance between the two extreme hydrogen atoms.František Mikeš, Geraldine Boshart, and Emanuel Gil-Av (1976): "Resolution of optical isomers by high-performance liquid chromatography, using coated and bonded chiral charge-transfer complexing agents as stationary phases". Journal of Chromatography A, volume 122, pages 205-221. Adding two more rings on the same sense yields heptahelicene in which the two extreme rings overlap.
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99mTcO4− is advantageous for the synthesis of a variety of radiopharmaceuticals because Tc can adopt a number of oxidation states. The oxidation state and coligands dictate the specificity of the radiopharmaceutical. The starting material Na99mTcO4, made available after elution from the generator column, as mentioned above, can be reduced in the presence of complexing ligands. Many different reducing agents can be used, but transition metal reductants are avoided because they compete with 99mTc for ligands.
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Cisplatin, PtCl2(NH3)2, is a coordination complex of platinum(II) with two chloride and two ammonia ligands. It is one of the most successful anticancer drugs. A coordination complex consists of a central atom or ion, which is usually metallic and is called the coordination centre, and a surrounding array of bound molecules or ions, that are in turn known as ligands or complexing agents. Many metal-containing compounds, especially those of transition metals, are coordination complexes.
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Based on definition from IUPAC, coordination polymerization is a chain polymerization that involves the preliminary coordination of a monomer molecule with a chain carrier. The monomer is firstly coordinated with the transition metal active center, and then the activated monomer is inserted into the transition metal-carbon bond for chain growth. In some cases, coordination polymerization is also called insertion polymerization or complexing polymerization. Advanced coordination polymerizations can control the tacticity, molecular weight and PDI of the polymer effectively.
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Trisodium N-(1-carboxylatoethyl)iminodiacetate, methylglycinediacetic acid trisodium salt (MGDA-Na3) or trisodium α-DL-alanine diacetate (α-ADA), is the trisodium anion of N-(1-carboxyethyl)iminodiacetic acid and a tetradentate complexing agent. It forms stable 1:1 chelate complexes with cations having a charge number of at least +2, e.g. the "hard water forming" cations Ca2+ or Mg2+. α-ADA is distinguished from the isomeric β-alaninediacetic acid by better biodegradability and therefore improved environmental compatibility.
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It is then pumped through the underground orebody to recover the minerals in it by leaching. Once the pregnant solution is returned to the surface, the uranium is recovered in much the same way as in any other uranium plant (mill). In Australian ISL mines (Beverley, Four Mile and Honeymoon Mine) the oxidant used is hydrogen peroxide and the complexing agent sulfuric acid. Kazakh ISL mines generally do not employ an oxidant but use much higher acid concentrations in the circulating solutions.
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The outer portion of a SLMD consists of a section of sealed, flat, semi-permeable polyethylene tubing. Sealed inside this tubing is a 1:1 mixture of a hydrophobic metal complexing agent and a long chain organic acid. The organic acid diffuses through the tubing to the outer surface, where the carboxylic acid portion can form stable complexes with calcium and magnesium ions in the water. This allows a waxy layer to slowly accumulate on the outside of the tube.
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Apart from that, a higher pH (or higher Ca content) in the lower soil horizons can result in the breakdown of metal-humus complexes. In the lower soil layers, the organic complexing agents can be degraded by functioning microorganism. Already established complexes in the B horizon can act as a filter, as they adsorb the traveling complexes from the upper soil horizons. A decreased water conductivity due to higher clay content can also result in the early flocculation of organo-mineral complexes.
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In 1967, Charles Pedersen, who was a chemist working at DuPont, discovered a simple method of synthesizing a crown ether when he was trying to prepare a complexing agent for divalent cations. His strategy entailed linking two catecholate groups through one hydroxyl on each molecule. This linking defines a polydentate ligand that could partially envelop the cation and, by ionization of the phenolic hydroxyls, neutralize the bound dication. He was surprised to isolate a by-product that strongly complexed potassium cations.
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Citing earlier work on the dissolution of potassium in 16-crown-4, he realized that the cyclic polyethers represented a new class of complexing agents that were capable of binding alkali metal cations. He proceeded to report systematic studies of the synthesis and binding properties of crown ethers in a seminal series of papers. The fields of organic synthesis, phase transfer catalysts, and other emerging disciplines benefited from the discovery of crown ethers. Pedersen particularly popularized the dibenzo crown ethers.
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Besides its cosmetic application, Botox is used in the treatment of other conditions including migraine headache and cervical dystonia (spasmodic torticollis) (a neuromuscular disorder involving the head and neck). Dysport, manufactured by Ipsen, received FDA approval and is now used to treat cervical dystonia as well as glabellar lines in adults. In 2010, another form of botulinum toxin, one free of complexing proteins, became available to Americans. Xeomin received FDA approval for medical indications in 2010 and cosmetic indications in 2011.
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The solution is then applied to a resin, which different lanthanides bind in different matters. This is then dissolved using complexing agents, and due to the different types of bonding exhibited by the different lanthanides, it is possible to isolate the compounds. Ytterbium is separated from other rare earths either by ion exchange or by reduction with sodium amalgam. In the latter method, a buffered acidic solution of trivalent rare earths is treated with molten sodium-mercury alloy, which reduces and dissolves Yb3+.
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By complexing the sensor with a cation, the conditions for electron transfer are altered so that the quenching process is blocked, and fluorescence emission is 'switched on'. The probability of PET is governed by the overall free energy of the system (the Gibbs free energy ΔG). The driving force for PET is represented by ΔGET, the overall changes in the free energy for the electron transfer can be estimated using the Rehm-Weller equation. Electron transfer is distance dependent and decreases with increasing spacer length.
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Iminodisuccinic acid has been distributed by Lanxess since 1998 under the trade name Baypure CX 100 as complexing agent. It reacts with the calcium and magnesium ions in water and forms chelate complexes of medium stability. This complexation prevents the formation of insoluble salts (deposits) and soaps (lime soaps) and thus improves the effect of detergents and dishwashing detergents, hand soaps and shampoos. As a result, the amount of conventional builders in solid detergents (carbonates, silicates, phosphates, citrates, zeolites) can be reduced or fully replaced.
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Complexes of tetrasodium iminodisuccinate with Fe3+, Cu2+, Zn2+ and Mn2+ ions are used as micronutrients, as they are providing important trace elements for plants in readily absorbable form; both granulated as soil fertilizer and dissolved as foliar spray. The so far commonly in plant protection applied complexing agents such as EDTA, DTPA (diethylenetriamine pentaacetic acid), EDDHA (ethylenediamine dihydroxyphenylacetic acid) or HBED (N,N'-di(2-hydroxybenzyl)ethylenediamine-N, N'-diacetic acid) are difficult to virtually non-biodegradable. In contrast, IDHA trace element complexes offer an interesting alternative.
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Sodium triphosphate (STP), also sodium tripolyphosphate (STPP), or tripolyphosphate (TPP),Complexing agents, Environmental and Health Assessment of Substances in Household Detergents and Cosmetic Detergent Products, Danish Environmental Protection Agency, Accessed 2008-07-15) is an inorganic compound with formula Na5P3O10. It is the sodium salt of the polyphosphate penta-anion, which is the conjugate base of triphosphoric acid. It is produced on a large scale as a component of many domestic and industrial products, especially detergents. Environmental problems associated with eutrophication are attributed to its widespread use.
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Hering realised that she preferred environmental sciences and moved to Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution for her graduate studies. She completed her PhD thesis "The Kinetics and Thermodynamics of Copper Complexation in Aquatic Systems" in 1988. Her supervisor, François Morel, described her research as "elegant work on the surprisingly slow kinetics of some reactions between trace metals and organic complexing agents in natural water". She described the preparation of Aquil, an artificial algal culture, and the coordination of transition metals in seawater.
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It is potentially multivalent for attachment to the complement fixation sites of immunoglobulin. The sites are on the CH2 domain of IgG and, it is thought, on the CH4 domain of IgM. IgG4 cannot bind C1q, but the other three IgG types can. The appropriate peptide sequence of the complement fixing site might become exposed following complexing of the immunoglobulin, or the sites might always be available, but might require multiple attachment by C1q with critical geometry in order to achieve the necessary avidity.
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Furthermore, 14-3-3ζ may regulate glucose receptor trafficking in response to insulin levels through its interaction with IRS1. In addition to cell survival, 14-3-3ζ regulates cell cycle progression through various ligands and processes. For instance, 14-3-3ζ controls cellular senescence by complexing with BIS to chaperone protein folding of STAT3 and activate the signaling pathway. Also, 14-3-3ζ can negatively regulate the G2-M phase checkpoint by binding and sequestering the cyclin-dependent kinases to the cytoplasm, thus inhibiting their activity.
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Podzolization usually occurs under forest or heath vegetation and is common in cool and humid climates as these climates inhibit the activity of soil microbes in the topsoil. Overall, podzolization happens where the decomposition of organic matter is inhibited and as a result, acidic organic surface (mor) layers build up. Under these typically acidic conditions, nutrient deficiency further hampers the microbial degradation of organic complexing agents. Medium to coarse textured soils with base-poor parent material (usually rich in quartz) also promote podzolization, as they encourage percolating water flow.
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Non-viral methods involve complexing therapeutic DNA to various macromolecules including cationic lipids and liposomes, polymers, polyamines and polyethylenimine, and nanoparticles. FuGene 6 and modified cationic liposomes are two non-viral gene delivery methods that have so far been utilized for gene delivery to cartilage. FuGene 6 is a non-liposomal lipid formulation, which has proved to be successful in transfecting a variety of cell lines. Liposomes have shown to be an appropriate candidate for gene delivery, where cationic liposomes are made to facilitate the interaction with the cell membranes and nucleic acids.
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MPC subsequently extended its economic research and development planning skills into the leisure industry, creating the concept of the Multi-Activity Family Entertainment Centre. After extensively researching leisure activities throughout the world, MPC developed the concept of the first Multi-Activity Family Entertainment Centre in the world. The concept was designed to fuse retailing elements with leisure activities. Recognising the leisure benefit of integrated retailing to the customer was an enormous step forward for both leisure and retailing industries and was the start of an explosion of consumer spending in a new sector of leisure complexing.
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The actinide elution sequence is reversed from that of the cation-exchange resin column, so that the heavier actinides elute later. The mendelevium separated by this method has the advantage of being free of organic complexing agent compared to the resin column; the disadvantage is that mendelevium then elutes very late in the elution sequence, after fermium. Another method to isolate mendelevium exploits the distinct elution properties of Md2+ from those of Es3+ and Fm3+. The initial steps are the same as above, and employs HDEHP for extraction chromatography, but coprecipitates the mendelevium with terbium fluoride instead of lanthanum fluoride.
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When a ligand activates the G protein-coupled receptor, it induces a conformational change in the receptor that allows the receptor to function as a guanine nucleotide exchange factor (GEF) that exchanges GDP for GTP – thus turning the GPCR "on". The GTP (or GDP) is bound to the Gα subunit in the traditional view of heterotrimeric GPCR activation. This exchange triggers the dissociation of the Gα subunit (which is bound to GTP) from the Gβγ dimer and the receptor as a whole. However, models which suggest molecular rearrangement, reorganization, and pre-complexing of effector molecules are beginning to be accepted.
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Cobalt(II) hydroxide precipitates as a solid when an alkali metal hydroxide is added to an aqueous solution of Co2+ salt.O. Glemser "Cobalt(II) Hydroxide" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1521. For example, :Co2+ \+ 2 NaOH → Co(OH)2 \+ 2 Na+ The compound can be prepared by reacting cobalt(II) nitrate in water with a solution of triethylamine as both the base and a complexing agent. It can also be prepared by elecrolysis of a solution of cobalt nitrate with a platinum cathode.
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Metal complexing has been shown to occur between natural nucleobases. A well-documented example is the formation of T-Hg-T, which involves two deprotonated thymine nucleobases that are brought together by Hg2+ and forms a connected metal-base pair. This motif does not accommodate stacked Hg2+ in a duplex due to an intrastrand hairpin formation process that is favored over duplex formation. Two thymines across from each other in a duplex do not form a Watson-Crick base pair in a duplex; this is an example where a Watson-Crick basepair mismatch is stabilized by the formation of the metal-base pair.
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These elements can be then identified simply based on their elution position/time, using α-hydroxyisobutyrate solution (α-HIB), for example, as eluant. Separation of the 3+ actinides can also be achieved by solvent extraction chromatography, using bis-(2-ethylhexyl) phosphoric acid (abbreviated as HDEHP) as the stationary organic phase, and nitric acid as the mobile aqueous phase. The actinide elution sequence is reversed from that of the cation-exchange resin column. The einsteinium separated by this method has the advantage to be free of organic complexing agent, as compared to the separation using a resin column.
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The Pourbaix diagram for uranium in a non-complexing aqueous medium (e.g. perchloric acid / sodium hydroxide) The Pourbaix diagram for uranium in carbonate solution. The dashed green lines show the stability limits of water in the system.. Ignasi Puigdomenech, Hydra/Medusa Chemical Equilibrium Database and Plotting Software (2004) KTH Royal Institute of Technology, freely downloadable software at Pourbaix diagrams are also known as EH-pH diagrams due to the labeling of the two axes. The vertical axis is labeled EH for the voltage potential with respect to the standard hydrogen electrode (SHE) as calculated by the Nernst equation.
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The original FIAM did not address other roles that ligands play besides complexing metals and how these other roles could affect the biological response of an organism. Around the same time that the free ion activity model was proposed, the gill surface interaction model (GSIM) was introduced by Pagenkopf in 1983. The model was put into use in order to evaluate toxicity test results of metals as well as metals in mixtures. Pagennkopf outlined that the compilation of previous studies on metals necessitated further examination of how metal toxicity changes as a function of pH, hardness and complexation capacity for the toxicity of metals to fishes.
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By complexing metal ions into the polymer matrix, the strength and toughness of the ionomer system is increased. Some applications where ionomers were used to increase the toughness of the overall system include coatings, adhesives, impact modification, and thermoplastics, one of the most known examples being the use of Surlyn in the outer layer of golf balls. The ionomer coating improves the toughness, aerodynamics, and durability of the golf balls, increasing their lifetime. Ionomers can also be blended with resins to increase the cohesive strength without diminishing the overall tackiness of the resin, creating pressure sensitive adhesives for a variety of applications, including water or solvent-based adhesives.
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As a subunit of SCS, SUCLG2 is a mitochondrial matrix enzyme that catalyzes the reversible conversion of succinyl-CoA to succinate and acetoacetyl CoA, accompanied by the substrate-level phosphorylation of GDP to GTP, as a step in the tricarboxylic acid (TCA) cycle. The GTP generated is then consumed in anabolic pathways. However, since GTP is not transported through the inner mitochondrial membrane in mammals and other higher organisms, it must be recycled within the matrix. In addition, SUCLG2 may function in ATP generation in the absence of SUCLA2 by complexing with the mitochondrial nucleotide diphosphate kinase, nm23-H4, and thus compensate for SUCLA2 deficiency.
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Cytoplasmic p21 expression can be significantly correlated with lymph node metastasis, distant metastases, advanced TNM stage (a classification of cancer staging that stands for: tumor size, describing nearby lymph nodes, and distant metastasis), depth of invasion and OS (overall survival rate). A study on immunohistochemical markers in malignant thymic epithelial tumors shows that p21 expression has a negatively influenced survival and significantly correlated with WHO (World Health Organization) type B2/B3. When combined with low p27 and high p53, DFS (Disease-Free Survival) decreases. p21 mediates the resistance of hematopoietic cells to an infection with HIV by complexing with the HIV integrase and thereby aborting chromosomal integration of the provirus.
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The CODH catalytic site, referred to as the C-cluster, is a [3Fe-4S] cluster bonded to a Ni-Fe moiety. Two basic amino acids (Lys587 and His 113 in M.thermoacetica) reside in proximity to the C-cluster and facilitate acid-base chemistry required for enzyme activity. Based on IR spectra suggesting the presence of an Ni-CO complex, the proposed first step in the oxidative catalysis of CO to CO2 involves the binding of CO to Ni2+ and corresponding complexing of Fe2+ to a water molecule. The binding of CO molecule causes a shift in the coordination of the Ni atom from a square-planar to square pyramidal geometry.
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Elevated Hsp70 levels in tumor cells may increase malignancy and resistance to therapy by complexing, and hence, stabilizing, oncofetal proteins and products and transporting them into intracellular sites, thereby promoting tumor cell proliferation. As a result, tumor vaccine strategies for Hsp70s have been highly successful in animal models and progressed to clinical trials. Alternatively, overexpression of Hsp70 can mitigate the effects of neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease (PD), Huntington’s disease, and spinocerebellar ataxias, and aging and cell senescence, as observed in centenarians subjected to heat shock challenge. HSPA1L may fight against PD by co-regulating the translocation of parkin to damaged mitochondria, thus facilitating their removal.
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Rb is able to be localize to sites of DNA breaks during the repair process and assist in non-homologous end joining and homologous recombination through complexing with E2F1. Once at the breaks, Rb is able to recruit regulators of chromatin structure such as the DNA helicase transcription activator BRG1. Rb has been shown to also be able to recruit protein complexes such as condensin and cohesin to assist in the structural maintenance of chromatin. Such findings suggest that in addition to its tumor suppressive role with E2F, Rb is also distributed throughout the genome to aid in important processes of genome maintenance such as DNA break-repair, DNA replication, chromosome condensation, and heterochromatin formation.
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Synthese von Aminoethylpiperazin durch Hydrierung von NTAN If the catalytic hydrogenation of NTAN is carried out with e. g. Raney nickel in the presence of a large excess of ammonia, it gives tris(2-aminoethyl)amine.Synthese von Tris(2-aminoethyl)amin (tren) Tris(2-aminoethyl)amine is used as a tetrazident complexing agent (abbreviated as "tren"), which forms stable chelates, particularly with divalent and trivalent transition metal ions. Nitrilotriacetonitrile reacts with methanal at pH 9.5 to give 2,2-dihydroxymethyl-nitrilotriacetonitrile, which is hydrolyzed with sodium hydroxide solution at 100 °C to give the trisodium salt of 2-hydroxymethylserine-N,N-diacetic acid, from which the free acid can be obtained by acidification in 51% yield.
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Synthese von 2-Hydroxymethylserin-N,N-diessigsäure-trinatriumsalz aus NTAN The compound is suitable as a complexing agent for heavy metal ions or alkaline earth metal ions, as a stabilizer for bleaching agents (e.g. for sodium perborate, in solid detergent preparations) and as a builder in detergents for inhibiting the formation of incrustations in textiles during laundering. The hydrolysis of nitrilotriacetonitrile with water in concentrated sulfuric acid yields under gentle conditions practically quantitatively nitrilotriacetamide, which has been investigated as a neutral tetradentate ligand for metal complexation. At elevated temperature, 3,5-dioxopiperazine-1-acetamide is formed by ring closure, which can be quantitatively converted into the nitrilotriacetamide after neutralization and heating with excess aqueous ammonia.
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In metal base-pairing, the Watson-Crick hydrogen bonds are replaced by the interaction between a metal ion with nucleosides acting as ligands. The possible geometries of the metal that would allow for duplex formation with two bidentate nucleosides around a central metal atom are: tetrahedral, dodecahedral, and square planar. Metal-complexing with DNA can occur by the formation of non-canonical base pairs from natural nucleobases with participation by metal ions and also by the exchanging the hydrogen atoms that are part of the Watson-Crick base pairing by metal ions. Introduction of metal ions into a DNA duplex has shown to have potential magnetic, conducting properties, as well as increased stability.
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After Calcein-AM is taken up into the cell, it is converted by esterases into calcein (below). This is capable of complexing calcium ions, resulting in a green fluorescence. Since only living cells possess sufficient esterases, only live cells fluoresce green after excitation The non-fluorescent acetomethoxy derivate of calcein (calcein AM, AM = acetoxymethyl) is used in biology as it can be transported through the cellular membrane into live cells, which makes it useful for testing of cell viability and for short-term labeling of cells. Alternatively, Fura-2 , Furaptra , Indo-1 and aequorin may be used. An acetomethoxy group obscures the part of the molecule that chelates Ca2+, Mg2+, Zn2+ and other ions.
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Trial well field for in-situ recovery at Honeymoon, South Australia In-situ leaching (ISL), also known as solution mining, or in- situ recovery (ISR) in North America, involves leaving the ore where it is in the ground, and recovering the minerals from it by dissolving them and pumping the pregnant solution to the surface where the minerals can be recovered. Consequently, there is little surface disturbance and no tailings or waste rock generated. However, the orebody needs to be permeable to the liquids used, and located so that they do not contaminate ground water away from the orebody. Uranium ISL uses the native groundwater in the orebody which is fortified with a complexing agent and in most cases an oxidant.
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Solid block weights can corrode and be damaged when dropped or impacting other weights. In flexible bag weights, the small pieces of lead shot will rub together when handled and used, releasing lead dust and corrosion products into the water. The amount of lead lost to the water is roughly proportional to the total surface area of the weights, and the amount of motion between contact surfaces and is greater for smaller sizes of shot. Solubility of lead salts in seawater is low, though there is a significant role played by natural organic matter in complexing dissolved lead, and oceanic lead concentrations typically range from 1 to 36 ng/L, with from 50 to 300 ng/L in coastal waters affected by anthropogenic activities.
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Elevated Hsp70 levels in tumor cells may increase malignancy and resistance to therapy by complexing, and hence, stabilizing, oncofetal proteins and products and transporting them into intracellular sites, thereby promoting tumor cell proliferation. As a result, tumor vaccine strategies for Hsp70s have been highly successful in animal models and progressed to clinical trials. One treatment, a Hsp72/AFP recombined vaccine, elicited robust protective immunity against AFP-expressing tumors in mice experiments. Therefore, the vaccine holds promise for treating hepatocellular carcinoma. Alternatively, overexpression of Hsp70 can mitigate damage from ischemia-reperfusion in cardiac muscle, as well damage from neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and spinocerebellar ataxias, and aging and cell senescence, as observed in centenarians subjected to heat shock challenge.
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Pancreatic ribonucleases (, RNase, RNase I, RNase A, pancreatic RNase, ribonuclease I, endoribonuclease I, ribonucleic phosphatase, alkaline ribonuclease, ribonuclease, gene S glycoproteins, Ceratitis capitata alkaline ribonuclease, SLSG glycoproteins, gene S locus-specific glycoproteins, S-genotype-assocd. glycoproteins, ribonucleate 3'-pyrimidino- oligonucleotidohydrolase) are pyrimidine-specific endonucleases found in high quantity in the pancreas of certain mammals and of some reptiles. Specifically, the enzymes are involved in endonucleolytic cleavage of 3'-phosphomononucleotides and 3'-phosphooligonucleotides ending in C-P or U-P with 2',3'-cyclic phosphate intermediates. Ribonuclease can unwind the RNA helix by complexing with single-stranded RNA; the complex arises by an extended multi-site cation-anion interaction between lysine and arginine residues of the enzyme and phosphate groups of the nucleotides.
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Because bicarbonate is itself a recycling substrate and the kinetics of cyanase include a rapid and random equilibrium, bicarbonate can also act as an enzyme inhibitor. At low concentrations, bicarbonate shows uncompetitive inhibition, where it binds to the one of enzyme's anionic binding sites, and inhibit cyanate binding, or bicarbonate can bind once more so that the enzyme complex is bound to two bicarbonates in its double anion active site. At higher concentrations, the trend moves toward non-competitive inhibition, where the incorrect, dead-end complex must decompose to the initial separated units before the binding action can begin again. This random equilibrium of cyanate and bicarbonate complexing with the enzyme causing substrate inhibition is referred to as ping pong inhibition.
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Blotter paper containing 25C-NBOMe Anecdotal reports from human users suggest 25C-NBOMe to be an active hallucinogen at a dose of as little as 200-500 µg insufflated and 300-600 µg buccally (with threshold doses even lower), making it only half to a third the potency of LSD.2C-C-NBOMe Dose - erowid NBOMe-substituted compounds have a diminished absorption rate passing through mucus membranes, but generally remain inactive when taken orally. Buccal, sublingual or insufflated routes of administration are all viable options. Absorption rate buccally and sublingually can be increased when complexed with HPBCD complexing sugar, however the most efficient is nasal administration, which shortens the duration while increasing intensity, but has been attributed to several overdoses due to improper dosing.
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Elevated Hsp70 levels in tumor cells may increase malignancy and resistance to therapy by complexing, and hence, stabilizing, oncofetal proteins and products and transporting them into intracellular sites, thereby promoting tumor cell proliferation. As a result, tumor vaccine strategies for Hsp70s have been highly successful in animal models and progressed to clinical trials. One treatment, a Hsp72/AFP recombined vaccine, elicited robust protective immunity against AFP-expressing tumors in mice experiments. Therefore, the vaccine holds promise for treating hepatocellular carcinoma. Alternatively, overexpression of Hsp70 can mitigate damage from ischemia-reperfusion in cardiac muscle, as well damage from neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and spinocerebellar ataxias, and aging and cell senescence, as observed in centenarians subjected to heat shock challenge.
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Care must be taken when handling some of the residues as they contain 228Ra, the daughter of 232Th, which is a strong gamma emitter. Praseodymium may then be separated from the other lanthanides via ion-exchange chromatography, or by using a solvent such as tributyl phosphate where the solubility of Ln3+ increases as the atomic number increases. If ion-exchange chromatography is used, the mixture of lanthanides is loaded into one column of cation-exchange resin and Cu2+ or Zn2+ or Fe3+ is loaded into the other. An aqueous solution of a complexing agent, known as the eluant (usually triammonium edtate), is passed through the columns, and Ln3+ is displaced from the first column and redeposited in a compact band at the top of the column before being re-displaced by .
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Potassium bitartrate can be mixed with an acidic liquid such as lemon juice or white vinegar to make a paste-like cleaning agent for metals such as brass, aluminium or copper, or with water for other cleaning applications such as removing light stains from porcelain. This mixture is sometimes mistakenly made with vinegar and sodium bicarbonate (baking soda), which actually react to neutralize each other, creating carbon dioxide and a sodium acetate solution. Cream of tartar was often used in traditional dyeing where the complexing action of the tartrate ions was used to adjust the solubility and hydrolysis of mordant salts such as tin chloride and alum. Cream of tartar, when mixed into a paste with hydrogen peroxide, can be used to clean rust from some hand tools, notably hand files.
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To further increase the energy density of the zinc-iodide flow battery, bromide ions () are used as the complexing agent to stabilize the free iodine, forming iodine-bromide ions () as a means to free up iodide ions for charge storage. Traditional flow battery chemistries have both low specific energy (which makes them too heavy for fully electric vehicles) and low specific power (which makes them too expensive for stationary energy storage). However a high power of 1.4 W/cm2 was demonstrated for hydrogen-bromine flow batteries, and a high specific energy (530 Wh/kg at the tank level) was shown for hydrogen-bromate flow batteries One system uses organic polymers and a saline solution with a cellulose membrane. The prototype withstood 10000 charging cycles while retaining substantial capacity.
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This led to many joint papers over the coming decade in which the theory was tested and successfully applied to a wide range of liquid mixtures. However, there still remained an important limitation, the failure of these existing theories to describe molecular association due to strongly attractive forces, such as hydrogen bonding. In the late 1980s Michael Wertheim developed a highly successful theory for dense fluids in which the molecules exhibited association to form complexing, through hydrogen-bonding, charge transfer and other mechanisms. In 1989 Keith, together with co-workers Walter Chapman, George Jackson and Mac Radosz, proposed an equation of state, which they termed statistical associating fluid theory (SAFT), that combined the merits of Werheim's associating liquid theory with a perturbation treatment that described the non-polar interactions.
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Purification of the three types of cyclodextrins takes advantage of the different water solubility of the molecules: β-CD which is poorly water- soluble (18.5 g/l or 16.3mM) (at 25C) can be easily retrieved through crystallization while the more soluble α- and γ-CDs (145 and 232 g/l respectively) are usually purified by means of expensive and time consuming chromatography techniques. As an alternative a "complexing agent" can be added during the enzymatic conversion step: such agents (usually organic solvents like toluene, acetone or ethanol) form a complex with the desired cyclodextrin which subsequently precipitates. The complex formation drives the conversion of starch towards the synthesis of the precipitated cyclodextrin, thus enriching its content in the final mixture of products. Wacker Chemie AG uses dedicated enzymes, that can produce alpha-, beta- or gamma-cyclodextrin specifically.
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These results were initially challenged by some authors, but subsequent experiments involving the detailed analysis of the decomposition products, complemented by computational studies, bore out the initial conclusion. The pentazolide anion is not expected to last longer than a few seconds in aqueous solution without the aid of complexing agents. The discovery of pentazoles spurred attempts to create all-nitrogen salts such as , which should be highly potent propellants for space travel. In 2002 the pentazolate anion was first detected with electrospray ionization mass spectrometry Vij, A., Pavlovich, J. G., Wilson, W. W., Vij, V. and Christe, K. O. (2002), Experimental Detection of the Pentaazacyclopentadienide (Pentazolate) Anion, cyclo-N5−. Angew. Chem. Int. Ed., 41: 3051–3054. In 2016 the ion was also detected in solution.B. Bazanov, U. Geiger, R. Carmieli, D. Grinstein, S. Welner, Y. Haas,Detection of Cyclo-N5− in THF Solution Angew. Chem. Int. Ed. 2016, 55, 13233. In 2017, white cubic crystals of the pentazolate salt, (N5)6(H3O)3(NH4)4Cl were announced.
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1,4-butanesultone reacts smoothly with nucleophiles such as ammonia to form the corresponding zwitterionic, usually very water-soluble sulfobutylbetaines. Synthese von 4-Aminobutan-1-sulfonsäure aus 1,4-Butansulton Sulfobetaines with longer alkyl chains (CnH2n+1 mit n > 10) show interesting properties as surface-active compounds (surfactants, detergents) with antimicrobial properties. Synthese eines Alkylpiperidinsulfobetains-Surfactants In the reaction of N-N- butylimidazole with 1,4-Butansultone in Toluene in a 98% yield is formed 1-butylimidazolium-3-(n-butylsulfonate) Synthese von ionischen Flüssigkeiten vom Chlorbutylsulfonat-Typ 1-Butylimidazolium-3-(n-butylsulfonate) catalyses as a component of multifunctional catalysts the reaction of platform chemicals from biomass (for example levulinic acid or itaconic acid) into the corresponding lactones, diols or cyclic ethers. Aminoalkylphosphonic acids (such as aminomethane diphosphonic acid, accessible from phosphorus trichloride, formamide and phosphonic acid) form with 1,4-butanesultone N-(sulfobutyl)aminomethane diphosphonic acids: Synthese von N-(Sulfobutyl)aminomethandiphosphonsäure-Komplexbildnern N-(sulfobutyl)aminomethane diphosphonic acid is characterized by very high water solubility (< 1000 g·l−1) and a strong capability as complexing agent and water softener.
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