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Vol 6, No 6 (2011)
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THEORETICAL BASES OF CHEMICAL TECHNOLOGY

3-18 54
Abstract
This review is devoted to studying the results of concentration oscillations phenomena observed in unsaturated compounds oxidative carbonylation. These homogeneous reactions are catalyzed by metal complexes. The second part of the review is devoted to describing various alkynes oxidative carbonylation, which can occur in oscillation mode. The main results of mathematic modeling of the studied systems are described.
19-22 38
Abstract
The geometry, electronic structure and stability of endohedral complexes Pdn@C60, n=1,…,4, were investigated by a quantum chemistry method (DFT/PBE). The heat of formation ΔНf of a complex consisting of C60 and n Pd atoms was used as a measure of complex stability. In particular, it was is established that this reaction is exothermal for n=1-3 and endothermal for n=4.
23-29 54
Abstract
Analysis of heat cost for rectification was performed taking into account the phase state of the original mixture. The conditions, under which pre-condensation of vapour before its inlet into the column is economically expedient, were found.
30-34 89
Abstract
This investigation studied the sorption of NO by activated carbons, zeolites and aluminum oxide at ambient temperature. It was found that γ-Al2O3 has the highest sorption capacity (45-50%). Among the studied activated carbons only AG-3 sample proved to be competitive with samples of γ-Al2O3. The NO sorption degree of the studied zeolites was less than 7%.
35-42 39
Abstract
Calculations of parameters of function of full electron density in molecules of dicarba-nido-undecaborates were carried out by the first order Promega method using MP2(full)/6-311++G(2d,p) level of theory. The features of electron structure of undecaborates and the relation of parameters of function of full electron density with their chemical properties were revealed.
43-48 50
Abstract
Theoretical calculations of the potential energy surfaces along the minimum energy pathway have been performed for elementary step-wise dehydration reactions of ammine magnesium borohydride and alumohydride complexes Mg(MH4)2(NH3)2 and their dimers [Mg(MH4)2(NH3)2]2 (M = В и Al) by using the density functional (B3LYP) and coupled cluster (CCSD(T)) methods with the 6-311++G** basis set.
49-53 53
Abstract
The influence of recycled flow operation on the value of minimum energy consumption for total conversion of A reagent to B product was studied with A↔B reaction as an example.
54-64 60
Abstract
Consideration of objects of various fields of knowledge has shown that isomerism is a general scientific concept. Examples illustrating its manifestation in heterogeneous equilibria thermodynamics and chemical technology are given.

CHEMISTRY AND TECHNOLOGY OF ORGANIC SUBSTANCES

65-68 59
Abstract
The possibility of intensifying the process of transesterification of triglycerides of carboxylic acids of vegetable oils with alcohols C1-C3 in the presence of potassium hydroxide in an apparatus with a vortex sheet is shown. Analysis of the composition of mixtures of methyl esters of carboxylic acids of sunflower oil showed that the redistribution of hydrogen and the destructive transformation in the system take place along with the transesterification reactions. This results in the expenditure of octadecyl acid ether.
69-71 58
Abstract
The preparative synthesis of bioactive arylheteroaliphatic N-substitued aminoamides based on the opening of epoxide ring of styrene oxide followed by acylation of diaminoalcohols with acyl chlorides, was developed.

CHEMISTRY AND TECHNOLOGY OF MEDICINAL COMPOUNDS AND BIOLOGICALLY ACTIVE SUBSTANCES

72-76 41
Abstract
Universal efficient preparative approach for obtaining of γ-substitued polyamide DNA-mimics on the base of L-alanine and L-glycine derivates was presented. As result of research cytosine and adenine-containing final monomers were synthesised. It was found that both allyl and methyl C-terminal protecting group can be used in the synthesis as example of cytosine-containing derivates.
77-83 45
Abstract
We investigated an in vitro system for the analysis of template switching effect of RNA-dependent DNA-polymerase during reverse transcription reaction. An RT-PCR-based approach was realized. An RNA sample was used as a template. The RNA contains a region with a stable secondary structure flanked by two homologous sequences. The described system can find use for testing overall performance of new and existing forms of the reverse transcriptase.
84-87 73
Abstract
The optimal composition of Methylophilus quaylei culture medium for the exopolysaccharide production increasing were selected (the ratio C/N, the concentration of phosphate and calcium chloride). Worked out conditions for the isolation, defined carbohydrate and fractional composition of exopolysaccharide M. quaylei.

CHEMISTRY AND TECHNOLOGY OF INORGANIC MATERIALS

88-92 63
Abstract
The work is dedicated to reactivation of mother liquor of heap and sunken uranium leaching. A new method offers reactivation without using oxidizing additives. Electrochemical treatment presumes direct oxidation of Fe2+ ions, which the mother liquor contains. An advantage of the electrochemical method is that it's less expensive than using additives and much easier to use in cross-country conditions. The cost-efficiency of electrochemical treatment versus polianite additive method was shown.
93-98 52
Abstract
The nano-composite materials with different morphology and structure, including yttrium basic carbonate or yttrium oxide and palladium metal are obtained. The optimal conditions for synthesis of stable nanoparticles of yttrium basic carbonate are defined. It is established that yttrium basic carbonate goes to the oxide at 900 °C. Samples of nanomaterials were characterized by transmission electron microscopy, infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy.
99-101 46
Abstract
Electrophysical properties of solid solutions and composite structures of system SnO2 - TiO2 were studied. Values of specific volume resistivity, factors of temperature sensitivity and temperature factors of resistance of solid solutions and compositions formed as a result of their disintegration were defined. The possibility of qualitative evaluation of the kinetics of the solid-phase disintegration of solid solutions by measuring of electrical resistivity was shown.
102-104 73
Abstract
A chemical-technological process of preparing nano-sized zinc oxide as a shell of magnetite was developed. A comparative analysis of the size, shape, composition and spectral characteristics of ZnO nanoparticles in the initial dispersion and on the surface of Fe3O4 was carried out.

SYNTHESIS AND PROCESSING OF POLYMERS AND POLYMERIC COMPOSITES

105-108 60
Abstract
Blends based on polyethelene and 1,2-polybutadiene were studied. The influence of methods for obtaining dynamically vulcanized thermoelastoplastic composites on the kinetics of DTPV structure formation, rheological and mechanical characteristics of samples was investigated.
109-112 55
Abstract
Research of adhesive and strength properties of vinylaromatic thermoplastic elastomers presented at the russian market show significant differences between them. That due not only different chemical nature of block copolymers, but also differences in their structural parameters.
113-119 66
Abstract
The article considers results of rheological studies of dilute aqueous dispersions of montmorillonite near the sol-gel transition. Results of dynamic light scattering, rotational viscometry, and adsorption data reveal the presence of a critical concentration of the structure formation, which is strongly influenced by the electrolyte (NaCl) concentration in the dispersion. Bentonite dispersion behaves differently with respect to the NaCl content near the critical concentration just before and after it. When we have a smaller particle concentration in the dispersion, extreme dependence of the strength and viscosity characteristics on the NaCl concentration is evident, while monotonic dependence exists at high particle concentration up to attaining the maximal value of the gel tensile strength. The critical concentration obtained from viscometry data is close to the theoretical value obtained for the simplified model in the approximation of hard spheres.
120-127 61
Abstract
The technological characteristics of spinning polymer solutions (viscosity, conductivity) and the parameters of the EPI - a process based on poly-3-hydroxybutyrate modified with nanoscale titanium dioxide were optimized. The composite materials were studied by X-ray diffraction, differential scanning calorimetry, infrared spectroscopy and physico-mechanical analysis (tensile test, elongation). A significant improvement in their physical and mechanical properties (breaking length, elongation) and resistance to the maturing were found.


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