Scientific Journal of KubSAU

Polythematic online scientific journal
of Kuban State Agrarian University
ISSN 1990-4665
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335 kb

SYNTHESIS OF SUBSTITUTED PYRIDINE- 3-SULFONYL ISOCYANATES AND PYRIDINE- 3-SULFONYL UREAS

abstract 1121508020 issue 112 pp. 274 – 286 30.10.2015 ru 1113
Acylation of amides substituted with pyridine-3- sulfonic acids oxalil-chlorides and phosgene was studied. New pyridil-3-sulfonil isocyanates were synthesized. The conditions for this synthesis were optimized by taking into account the detailed understanding of this acylation. The synthesized pyridine-3-sulfonyl isozyanates were converted to pyridine-3-sulfonyl ureas. Biological activity of the new compounds was studied and the substances with high herbicidal effect were found
280 kb

VOLTAMMETRY AND ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY OF MEMBRANE SYSTEMS UNDER STABILIZED DIFFUSION LAYER THICKNESS

abstract 1131509094 issue 113 pp. 1326 – 1342 30.11.2015 ru 1160
The current-voltage characteristics and the number of effective ion transfer, as well as the frequency spectrum of the electrochemical impedance of multilayer ion-exchange membranes in a stable and controllable thickness of the diffusion layer were measured, using the of rotating membrane disk complex. The article presents a comparative analysis of the frequency spectra of the electrochemical impedance of the source and a surface-modified monopolar anion exchange membranes in 0.01 M sodium chloride was made. The process of water molecules dissociation at current densities above the limiting one in 0.01 M sodium chloride solution was studied in detail
172 kb

ABOUT AN INTERACTION OF 3-AMINOTHIENO[2,3-b]PYRIDINE-2-CARBOX-AMIDES WITH AROMATIC ALDEHYDES UNDER CONDITIONS OF ACID CATALYSIS

abstract 1111507039 issue 111 pp. 695 – 707 30.09.2015 ru 1179
The present article belongs to the area of organic chemistry, namely, to chemistry of heterocyclic compounds. For the purpose of optimization of a method of synthesis the threecyclic heteroaromatic systems containing a pyridi-ne, thiophen and pyrimidine ring in one molecule, - tetrahydropyridothienopyrimidinon and dihydropyri-dothienopyrimidinon – reaction 3-aminothieno[2,3-b]-pyridine-2-carbokxamides with aromatic aldehydes is studied, some of which contain pharmacolodical groups. Reaction was carried out in the conditions of an acid catalysis – is used p-TsOH. Influence of the nature of solvent (toluene, ethanol, mix ethanol-dimethilform-amide (1:1)) on the course and the direction of reaction are studied. It is established that carrying out reaction in toluene leads to the dihydropyrimidine containing in situation 2 phenyl, 4-bromphenyl deputies. In the presence in a molecule of initial aldehyde of the deputy in orto-situation tetrahydropyrimidine are formed. Use of ethanol mainly leads to formation of a tetrahydro-pyrimidine ring. Boiling of initial substances in mix ethanol-DMF yields the results similar to use of toluene, but time of reaction is reduced twice. The way of receiving the dihydroderivatives short-term boiling of tetrahydropyrimidine is found in mix isopropanol-DMF (a volume ratio of solvents 1:3). Identity of the received substances is proved by method of a thin layer chroma-tography. The structure of the synthesized connections is confirmed with the element analysis. The structure of tertagidropirimidinon and digidropirimidinon is proved with use of data of IK and NMR 1H of the spectral analysis
136 kb

THE RELATIONSHIP BETWEEN PROTECTIVE EFFECT AND QUANTUMCHEMICAL DESCRIPTORS OF THE MOLECULES USED AS THE HYDROGENATION INHIBITORS IN THE ENVIRONMENT MICROBIOLOGICAL CORROSION CAUSED BY DESULFOVIBRIO DESULFURICANS

abstract 1101506075 issue 110 pp. 1153 – 1157 30.06.2015 ru 1184
This publication examines the relationship between the structure of molecules of complexing (descriptors of electronic structure), which are used as inhibitors of hydrogen embrittlement of the steel grade St3, and the content of absorbed hydrogen in model samples-plates made of the above steel. The form of expression of this relationship is the correlation coefficient (CC) by Pearson
230 kb

PREPARATION OF GRAPHENE MATERIAL WITH BENZIMIDAZOLE FRAGMENTS

abstract 1341710056 issue 134 pp. 711 – 719 29.12.2017 ru 1195
The new benzimidazole-functionalized graphene material based on graphene oxide (GO) and 3,3',4,4'- tetraaminodiphenyl oxide (TADPO) was obtained under one-step hydrothermal synthesis conditions. According to IR spectroscopy and elemental analysis, as a result of the reaction, benzimidazole (BI) rings are formed, and the mass content of nitrogen is 12.3%. The new graphene material is characterized by excellent electrochemical efficiency in a threeelectrode supercapacitor. As a result of the redox activity of BI cycles the specific capacitance reaches 286 F/g at the scan rate of 2 mV/s, which is substantially higher than the reduced graphene oxide (RGO) sample obtained under similar conditions without using TADPO (159 F/g at 2 mV/s)
312 kb

THERMOREACTIVE OLIGOMERS FROM HEXAMETHYLENE-bis-MALEIMIDE and 5,5’- bis-BENZOTRIAZOLES, AND GLUED JOINTS ON BASE OF THEM

abstract 1141510035 issue 114 pp. 478 – 491 30.12.2015 ru 1233
A number of thermoreactive oligomers was obtained via the Michael interaction of molar excesses of hexamethylene-bis-maleimide with 5,5’-bisbenzotriazoles in melt. The structure of them was proved by the 13C spectroscopy method. The one-step synthesis in melt, without by-products evolution, in absence of organic solvents, additional reagents, and catalysts is the more acceptable in point of view of technology (a finished reaction product does not require any purification). The process itself is the nucleophile addition across double bond, and so it can be attributed to the atom-saving technologies. According to data of the dynamic scanning calorimetry (DSC) and the thermogravimetry (TG), oligomers fuse at 130.8–135.6 °С, cross-link at 185–250 °С, and begin their thermal destruction in air at temperatures of 400– 420 °С. The tensile strength at shear of the glued joints on base of oligomers (steel plates overlapped) is 14.2– 23.7 MPa (142–237 kgf/cm2 ). The positive effect from the introduce of 5,5’-bis-benzotriazolyl fragments into structure of bismaleimide thermoreactive oligomers on strength of the glued joints between metal plates was revealed
134 kb

SURFACE ENERGY OF POLYMERS (ELASTOMER COMPOSITIONS): A COMPARATIVE ANALYSIS OF THE VALUES OF SURFACE ENERGY PARAMETERS OF DEFECTS IN POLYMERS

abstract 1311707029 issue 131 pp. 301 – 310 29.09.2017 ru 1261
Surface energy of polymers determines such important properties of polymers like wetability, adhesion, ability adsorption of low molecular weight substances. Inner organization, the structure of the polymer and the dynamics of interaction between macromolecular chains are shown at last. At the same time, the micro-defects (inhomogeneity) of polymers, which is an integral part of the structure are changed during deformation and must contribute to changing of the surface energy and its components. This article solves the task of detecting changes in the parameters of surface energy of polymers under uniaxial deformation. Data for the quantitative indicators of the surface properties total surface energy and its dispersive and polar components are presented. The calculations showed that the disperse and polar components of all the samples of polymer materials are about 98% of the total and, therefore, is crucial. For the first time experimental data, illustrating the change of surface energy of polymeric materials had been obtained, including elastomeric compositions, when uniaxial deformation. The relative changes of the surface energy vary from 54.5 per cent to 125 %. A decrease of total surface energy and its dispersion component is observed during deformation of polymer samples of different structure and chemical nature
297 kb

STRUCTURE OF SPACE CHARGE REGION AT BIPOLAR JUNCTION AND DISSOCIATION OF WATER MOLECULES IN BIPOLAR MEMBRANE MODIFIED BY CHROMIUM(III) COMPOUND

abstract 1041410075 issue 104 pp. 995 – 1014 30.12.2014 ru 1298
In the article the mathematical model of the space charge region in the bipolar membrane is considered. The structure of the space charge region under passing of electric current, and without electric current is discussed. The results of experimental studies of water dissociation in the bipolar membrane in the presence of chromium(III) are discussed
1320 kb

INFLUENCE OF HEAVY METALS HYDROXIDES ON WATER DISSOCIATION IN BIPOLAR MEMBRANE

abstract 1141510020 issue 114 pp. 275 – 287 30.12.2015 ru 1345
The 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
177 kb

THE DIPOLE MOMENTS AND THE STRUCTURE OF THE FOUR-MEMBERED CLOSED-CHAIN ARSENIC COMPOUNDS

abstract 0781204020 issue 78 pp. 234 – 243 30.04.2012 ru 1402
By 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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