Fine Chemical Technologies

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Vol 9, No 5 (2014)
View or download the full issue PDF (Russian)


3-10 58
Free radical mechanism of a cell damage is one of the universal non-specific pathogenic pathways in a cause of many diseases, including cancer, neurodegenerative diseases, atherosclerosis and aging. So in nuclear and mitochondrial DNA, guanine hydroxylation to 8-position gives 8­hydroxy­2'­deoxyguanosine (8­OH­dG) and 8­oxo­7,8­dihydro­2'­deoxyguanosine (8­oxo­dG). These substances are one of the predominant products of free radical­induced oxidative damages. They are usually been applied as biomarkers of oxidative stress and carcinogenesis. The direct oxidation of guanine or incorrect inclusion of 8-oxo-dGTP from the nucleotide pool by polymerases, lead to a lack of specificity of the base pairing in DNA, favoring mutagenesis. Firstly 8-oxo-dG has been described by H. Kasai and S. Nishimura in 1983. Since then, this damage has been widely measured in various tissues and body fluids as blood, urine, brain, liver, and others. Today 8-oxo-dG is already used not only as a marker of oxidative stress, but also as a tool for prognosis of diseases and results of applied therapy. Now many efforts are focused on developing the procedure of measurement of 8-oxo-dG content in tissues and body fluids. In this paper we also discuss the role of the 8-oxo-dG as a biomarker of oxidative stress and a predictor of diseases and results of the applied therapy.


11-15 44
Some variants of separation of binary eutectic mixtures by combining of fractional crystallization and single distillation with using compression heat pumps open type are considered. Influence of different technological parameters on the energy efficiency are analyzed.
16-20 39
The analysis of phase diagrams of quaternary systems with open splitting arrears was made. In relation to these diagrams an approach based on the analysis of Euler characteristic as a topological invariant of splitting diagrams was used. From one hand, Euler characteristic depends from the spheres dimension (for the second dimension it is 2). From the other hand, for diagram graphs it can be determined as a sum of elements of different dimensions. The presence of the open splitting area breaks the surface of the tetrahedron homeomorphic to the sphere into two parts. In this way Euler characteristic changes.
21-29 67
Some problems of mathematical modeling of distillation and chemical processes were discussed. The common and distinguishing features of these processes were revealed. The possibility of using the method of dynamical systems for studying these objects was shown, and some of special characteristics were revealed.


30-33 49
The solution copolymerization of styrene with vinylbenzyl trimethylammonium chloride (VBTMAC) was investigated. The solvents used in this study form homogeneous solutions with mixtures of monomers and possess different polarity, namely, isopropanol, DMSO, and their mixtures. Reactivity ratios of the copolymerization of these monomers in isopropanol were determined: rstyrene is 0.15 ± 0.01, rVBTMAC is 0.46 ± 0.004. Based on the values of the reactivity ratios authors conclude that the resulting copolymers have a tendency to alternate structural units. It was shown that the copolymerization of these monomers could not be described by means of Mayo-Lewis copolymerization model. The main reason for the deviation from the classical scheme of copolymerization is the bootstrap effect (the selective sorption of growing polymer radical by styrene). This effect increases with increasing polarity of the solvent as well as when the resulting copolymers are allocated in heterophase.
34-36 39
It is shown that the “bulk type” reactor proposed for obtaining carbon nanofibers from carbon monoxide can be used to obtain carbon nanofibers from organic raw materials electrocracking gas without changing the shape of the reaction cell. The “bulk type” reactor allows to combine the process of obtaining carbon nanofibers and separation of the formed products, and this allows to simplify the technology of carbon nanofibers. Varying the speed of the introduction of the catalyst in the synthesis zone under the same process conditions (temperature, volumetric gas flow rate, the composition of the gas) enables to obtain products with different characteristics. Using the maсrokinetics peculiarities of topochemical reactions of hydrocarbons decomposition it is possible to provide uninterrupted continued operation of the reactor and the obtaining of a product with the desired properties.
37-43 44
Copper supported catalysts based on preliminary oxidized carbon fibers have been studied. Nitric acid and hydrogen peroxide have been used for prior oxidation treatment of the supports. To characterize this materials N<sub>2</sub> adsorption-desorption and titration technics were used. Compared to nonoxidized activated carbon fibers, no significant changes in the texture of the modified supports were found, while there were differences in surface functionalities. Cupper supported catalysts were prepared by wetness impregnation and characterized by TPR, SEM. The influence of different surface functional groups on the distribution of active metal has been discussed. Besides, the catalysts were tested in the process of ethanol dehydrogenation. Cupper supported on activated carbon fibers preliminary oxidized with HNO<sub>3</sub> appeared to be more active in the process, although less stable at high temperatures. The reasons of the loss of activity have been also discussed.


44-48 45
The formation of the microstructure of metallization layers was investigated, and the calculations of the size of diffusion areas on the interphase boundaries in systems metal (Au, Ti, Pt)/GaAs and metal / metal was executed. The formation of the microstructure is accompanied by development in layers of internal stress. Internal stress in many respects determines the electrical and mechanical characteristics of the metallization layers and the influence of diffusion processes on the rate. Using the obtained results it is possible to choose purposefully the modes of drawing of metal layers and annealing structures in order to obtain systems of metallization with small internal stress and high level conductivity.
49-54 69
The work presents the results of investigations of physico-chemical properties of low hydrated hydroxides of niobium and tantalum – precursors for obtaining niobium and tantalum pentoxides with ordered phase and granulometric compositions


55-60 53
The quantum-chemical calculation of structures of sulfur vulcanization organic thiazole accelerators was performed. It was established that there is a correlation between the atomic electronegativity of nitrogen, the S–N length bond of and the rheokinetic properties of sulfur vulcanizates with Shungite and ZnO as activators. Moreover, scorching time was influenced on type of an activator. It should be noted that in the presence of Shungite under vulcanization began earlier than with ZnO except for MBT. So the strength of the physical adsorption of MBT on the surface of ZnO similars to Shungite.
61-63 102
The influence of solvent and surfactant (anionic and cationic) nature was discussed in this paper in order to find out the optimal conditions for the preparation of artificial latexes with different charges on the particle surface.
64-72 46
This paper describes the synthesis and the study of oligomers of bis(methacryloyl-oxy-1-hexamethylene-6-oxy)- ortho-phthaloyl (MHM-o-Ph) and its analog bis(methacryloyl-oxy-1-hexa-2,4-diyn-6-oxy)-ortho-phthaloyl (MHD-oPh) containing conjugated triple bonds in the oligomeric block. Besides the properties of polymers based on these oligomers were investigated. The polymerization of MHD-o-Ph conditions the formation of a bi-three-dimensional polymer, the skeleton of which contains a three-dimensional network of polymethacrylate macrochains and a network with a system of conjugated bonds. This system significantly affects the complex of the polymeric properties.


73-82 38
Numerous studies of the concept of a business model allow to formulate the most expedient structure of elements and the structure of this new administrative category. At the same time, the majority of researchers casually or intentionally exclude from attention the task of the organization of functioning of a business model.
83-85 50
A system model for the identification of the best available technology (BAT) was proposed on the basis of the system approach and the mathematical apparatus of set theory. The model allows to set up a problem of BAT identification for various chemical products manufactures and to solve the problem uniformly
86-93 67
A new form of representing the structures of saturated hydrocarbons as hypergraphs of special kind is suggested. A vertex of such hypergraph corresponds to a carbon atom in the molecule, and a hyperedge is defined as a set of vertices corresponding to some fixed carbon atom and all carbon atoms bounded with it. The comparison of the traditional graph model and the suggested hypergraph model using definite quantitative criteria related to some tasks of computer chemistry is fulfilled. For these investigations some set of hydrocarbons presented by their structural formulae is used. In particular, different invariants and codes of graphs and hypergraphs were calculated and their degeneration on the given set of structures was studied and compared. Two models were also compared by the ability of some local vertex invariants derived from them to distinguish topologically nonequivalent vertices in the traditional graph model. It is shown that in all cases in accordance with the used criteria the hypergraph model is better than the graph model. Besides, a number of structure–property relationships on the base of invariants of the suggested hypergraphs was obtained
94-95 48
The report focuses on features of technology of primary carbon sorbents based on lignin with the best adsorption characteristics.

ISSN 2410-6593 (Print)
ISSN 2686-7575 (Online)