02.00.00 Chemical sciences
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Description
The article is devoted to the research and working out of calculation method of thermodynamic data and phase diagrams of pentonary alloy materials of low-melt
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Description
In the article we have optimized reaction conditions of furfurilidenatseton with epichlorohydrin in the presence of a catalyst of tin chloride and held hydrogenation of double bond of 2-methylene -2 - [(2-furyl]-X-1,3 – dioxolan; we have also given the biological activity of some unsaturated furan 1,3- dioxolans
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Description
Correlations between values of the differences of first potentials ionization of atoms and molecules (ΔE) and valency angels α for three coordinated molecules of types ЭХ3 (Э=N, P, As, Sb are carried out; X=F, Cl, Br, I, CH3), and also ЭХ2 (Э=O, S, Se, Te; X = CH3, SiH3, GeH3) are described in this article. It is shown, that the entered value ΔE can serve as additive measure of change of the valency angle α in the basic and raised stances. We have also established that the functional dependences correlate with changes in the of hybridization of orbitals and the R parameters characterizing the interaction of electronic pairs near the central Э atom
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THE RESEARCH OF THE ANTIOXIDANT ACTIVITY OF WHEY BASED DRINKS
DescriptionData of the application of researches of vegetative components in reception of drinks from dairy whey of a functional purpose are shown
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Description
The stability of strongly basic anion-exchange membranes MA-41-2P (JSC "Schekino-Nitrogen", Russia) and AMX (Tokuyama Soda, Japan) under intensive current regimes was investigated in the current study. The process of water molecules dissociation at current densities above the limiting one in 0.01 M sodium chloride solution was studied in detail. The length of the electroconvective instability at the membrane / solution interface at currents exceeding the limiting current was measured by laser interferometry
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SYNTESIS OF 2-R-4-HYDROXYMETHYL-6-METHYLNICOTINATES OF ALKALINE METALS
DescriptionNew 2-R-4-hydroxymethyl-6-methylnikotinates of alkaline metals are synthesized by alkaline hydrolysis of derivatives 6-methyl-1,3-dihydrofuro-[3,4-c]pyridine-3-on
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INFLUENCE OF ORGANIC SOLVENTS ON WATER DISSOCIATION IN BIPOLAR MEMBRANE
DescriptionThe article discusses results of experimental research of the influence of aprotic and proton solvents on reaction rate of water molecules dissociation in the bipolar membrane MB-1 by the method of electrochemical impedance frequency spectrum. It was discovered, that addition of organic component in aqueous solutions results in significant influence on the parameters of water dissociation in a bipolar region of the membrane. The reason for this influence is the reduction of the mass fraction of water in solution and, consequently, in a bipolar region of the membrane, which itself reduces the rate of the dissociation reaction. Another reason for the influence of the organic solvent is its effect on the network of hydrogen bonds existing in water and aqueous solutions. Depending on the nature of organic solvent and its concentration, the network of hydrogen bonds may be strengthened, or destroyed, thus facilitating removal of the proton involved in the reactions between water molecules and catalytic centers in cation-exchange and anion-exchange layer of bipolar membrane, or retarding removal of proton. This leads respectively to speed up or slow down the rate of dissociation in the bipolar region of the membrane, as well as changing the constants of the dissociation reaction of water. Introduction of organic solvent in solutions, which are in the contact with bipolar membrane, is a convenient method of investigating the role of solution composition on the rate of proton transfer between water molecules and catalytic centers in the membranes
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Description
The method of nanoemulsions obtaining with acoustic chemistry method has been considered in the article, the nanoemulsion formula has been found. The researches for emulsion stability and particle sizes determination have been fulfilled. The antioxidant effect of the obtained emulsion and a possibility to use it in meat-vegetable products have been researched
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THE DIPOLE MOMENTS AND THE STRUCTURE OF THE FOUR-MEMBERED CLOSED-CHAIN ARSENIC COMPOUNDS
DescriptionBy the method of dipole moments, there has been determined that the tri-coordinated arsenic derivatives (p-XC6H4AsN-R)2 with R= Bu-t in the liquor exist in a cis-form, as for R=С6Н4Х-p the trans-structure is being realized. As for tetra-coordinated derivatives [XC6H4As(S)NBu-t]2 the trans-form is also beeing observed. For ortho-substituted connections, the angles of flat surfaces rotation of benzene rings have been defined
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INFLUENCE OF HEAVY METALS HYDROXIDES ON WATER DISSOCIATION IN BIPOLAR MEMBRANE
DescriptionThe results of study of bipolar membrane – analogue of MB-2, modified with chemically introduced chromium (III), iron (III) and nickel (II) hydroxides by the method of frequency spectrum of electrochemical impedance, by infrared spectroscopy and scanning electron microscopy in combination with X-ray spectrum analysis are presented. It is shown, that sequential treatment of cation-exchanger, contained in cationexchange membrane, with metal salt solution and alkali solution does not result in formation of complex compounds of these metals with ionic groups of ion exchanger. It was found that in these conditions the presence of heavy metals in the phase of cationexchanger confirmed by X-ray analysis, however, crystals of hydroxides of heavy metals are not detected in the size range of 1000 nm to 20 nm. These heavy metal compounds are thermally unstable and their catalytic activity in the reaction of dissociation of water molecules decreases with increasing temperature during heat treatment. The introduction of low-soluble hydroxides of d-metals (chromium (III), iron (III), nickel(II)) by chemical method can significantly improve the electrochemical characteristics of a bipolar membrane. The most effective catalysts in water dissociation reaction are the hydroxides of chromium (III) and iron (III) and, as a consequence, membranes with these hydroxides have a lower value of overpotential compared with original membrane at the same current density