Proc. of the Natl. Academy of Sciences of Belarus, Ser. Chemical Sci., 2009, No.2
/ Publications / Scientific Journals
Proc. of the Natl. Academy of Sciences of Belarus, Ser. Chemical Sci., 2009, No.2
| Proceedings of the National Academy of Sciences of Belarus
(Vestsi Natsiyanalnai Akademii Navuk Belarusi)
SERIES OF CHEMICAL SCIENCESPublished by The Belaruskaya Navuka Publishing House, Minsk, Republic of Belarus |
Number 2, 2009
CONTENTS
INORGANIC CHEMISTRY
Bashkirov L. A., Lubinski N. N., Petrov G. S., Shauchenka S. V., Sushkevich A. V., Sirota I. M.
Electroconductivity and thermo-emf of neodymium cobaltite-gallates NdCo1-xGaxO3. pp. 5--9
Summary: Ceramic samples of neodymium cobaltite-gallates NdCo1-xGaxO3 (x = 0; 0,1; 0,2; 0,3; 0,5; 0,7; 0,8; 0,9; 1,0) solid solutions have been prepared. It has been found that at 0 £ x £ 0,5 continuous series of solid solutions with cubic and at 0,5 << x £ 1,0 with rhombically (orthorhombically) distorted perovskite structure were formed. Electrical conduction and thermo-EMF of NdCo1-xGaxO3 have been studied in air at 300--1050 K. Activation energy of electrical conduction and thermo-EMF coefficient have been calculated.
Chizhova E. A., Klyndyuk A. I.
Thermal expansion, electrotransport and magnetic properties of layered barium-yttrium ferrocuprate with cation deficiency. pp. 10--14
Summary: The cationic nonstoichiometry effect on the structure, thermal expansion, electrical conductivity, thermo-EMF and magnetic susceptibility of yttrium-barium ferrocuprate has been studied. It has been found that unit cell parameters of YBaCuFeO5+d phase remained virtually unchanged upon formation of 5% vacancies in different cationic sublattices (Y, Ba, Cu/Fe) of its structure. The linear thermal expansion coefficient value of YBaCuFeO5+d derivatives decreases with formation of vacancies in its A-sublattice (Y, Ba). The Neel temperature of YBaCuFeO5+d increases with formation of iron vacancies and decreases with formation of copper vacancies in its structure.
Murashkevich A. N., Alisiyonok O. A., Lavitskaya A. S., Zharskii I. M.
Preparation and investigation of microspheric "SiO2 core -- TiO2 shell" composite. pp. 15--18
Summary: Composites "SiO2 core -- TiO2 shell" have been prepared from monodisperse silica and titania nanosol at various initial conditions. Titania content in the composite is 14--35 wt%. pH-dependence of zeta potential of the dispersion medium provides the evidence for formation of a composite with desired structure.
COLLOIDAL CHEMISTRY
Opanasenko O. N., Plikus O. A., Krut'ko N. P.
Kinetics of butadiene-styrene latex coagulation by inorganic salts. pp. 19--23
Summary: Coagulation kinetics of carboxylated butadiene-styrene latex by the multivalent cations (CaCl2, AlCl3, SnCl4) has been studied. It has been established that latex coagulation occurs under the action of A1Cl3 and SnCl4 only in acid medium, while in presence of CaCl2, coagulation occurs in alkaline medium. It has been shown that using CaCl2 as coagulant for formation of waterproof cover doesn't cause corrosion of the protected concrete surface.
Kuznetsova T. F., Rat'ko A. I.
Structural studies of silica using the comparative method. pp. 24--30
Summary: The data on low temperature physical adsorption-desorption of nitrogen studied by the volumetric static method have been transformed to comparative t- and as -plots to estimate the parameters of micro- and mesoporous structures of silicas templated by alkyl sulfate at various pH values. The information on the surface area of micropores and mesopores, their volume and average diameter, value of constant CBET, and also about mesopore size distribution has been obtained. It has been shown that reduction of specific surface of templated silica with increase of alkyl sulfate amount is caused by surface transformation towards adsorption potential decrease, especially appreciable at pH values > 5.0. The comparison plots of samples templated at pH 5.0 cut the positive line segment at the ordinate axis corresponding to micropore volume, and for samples templated at pH 7--8 the line segment cut is negative, that corresponds to reduction of adsorption potential. Using comparison plots has allowed to describe micro- and mesoporous structure of templated silicas with highly varied pore sizes.
Komarov V. S., Leonenko L. I., Rat'ko A. I., Kostyuk S. A.
Binary system of co-precipitated hydroxides with close values of precipitation pH. pp. 31--35
Summary: Co-precipitated systems of hydroxides have been studied, with equal sorption capacity and precipitation pH of hydroxides, and also with Vs of one component being greater than of the other one. It has been shown that source solution concentration and precipitation temperature affect sorption capacity of hydroxides. The findings have been theoretically substantiated. It has been demonstrated that co-precipitated hydroxides are promising for preparation of catalysts with even distribution of catalytically active component in volume and on the surface of samples.
PHYSICAL CHEMISTRY
Rabchinsky S. M., Streltsov E. A.
Photoelectrochemical properties of CdTe films electrodeposited under controlled potential conditions. pp. 36--39
Summary: Photoelectrochemical behavior of thin (1--2 mkm) CdTe films deposited on conducting SnO2 layers on glass has been studied. CdTe electodeposition was performed at constant potential by cathodic codeposition of Cd0 and Te0, cadmium was deposited in the form of atomic layers and tellurium - under diffusion overvoltage conditions. Studying the photocurrent spectral response of CdTe/electrolyte system provided the evidence that CdTe films have inhomogeneous height distribution of recombination centers -- their concentration is greater at the final step of film electrocrystallization. Defects concentration in CdTe correlates with nonstoichiometric tellurium concentration, whose partial deposition rate increases with time at constant electrode potential.
Mil'vit N. V., Shashkova I. L., Rat'ko A. I.
Heterogeneous synthesis of disubstituted calcium phosphate from calcium carbonate. pp. 40--44
Summary: The effect of phosphoric acid concentration, reagent molar ratio, temperature and other factors on kinetic parameters and yield of heterogeneous reaction between calcium carbonate and phosphoric acid has been studied. The industrially acceptable technology for preparation of calcium hydrogen phosphate has been developed.
Zelenkovsky V. M., Soldatov V. S., Bezyazychnaya T. V.
Quantum chemistry modeling for alkali metal salts of carboxylate cation exchangers. pp. 45--50
Summary: Nonempirical SCF MO LCAO calculations in molecular fragment approximation for waterless and hydrated alkali metal (Li, Na, K) salts of carboxylic ion exchangers have been performed. Systems containing from 1 to 6 functional groups have been considered. It has been shown that in waterless salts the cation is connected with two or three oxygen atoms from the neighboring carboxylic groups. The hydration reduces a number of the Me-O bonds by one. The characteristics of water molecules are given, depending on their interaction with functional groups, counter-ions and other water molecules.
Safonova A. M., Smetanina O. V., Shpilevskaya L. E.
Polymeric compositions based on metal-carbon fibers containing iron subgroup metals. pp. 51--56
Summary: It has been shown that modifying of carbon fibres with Ni, Co, Fe or their alloys gives them new properties and expands the field of their application. It is shown that these fibers are promising for use as fillers of polymeric matrixes for production of plastics with antifrictional, conductive and magnetic properties.
ORGANIC CHEMISTRY
Pashkovsky F. S., Shchukina E. M., Lakhvich F. A., Kuz'mitsky B. B., Golubeva M. B., Konoplya N. A., Lyubin G. S.
Synthesis and immunosuppressive activity of 10-oxa-13-aza and 11-oxa-13-azaprostanoids. pp. 57--62
Summary: A number of new 10-oxa-13-aza- and 11-oxa-13-azaprostanoids has been synthesized on the basis of tetronic acids and 3-acetyltetronic acids. Some heteroprostanoids obtained have been shown to possess immunosuppressive activity.
Dikusar E. A.
Semicarbazides and thiosemicarbazides of vanillin and vanillal esters. pp. 63--65
Summary: By the reaction of vanillin and vanillal esters with semicarbasone and thiosemicarbasone in methanol, previously unknown semicarbasides and thiosemicarbasides have been synthesized.
Kauhanka M. N., Sokolov S. N., Charnou Ju. G., Kashkan Zh. N., Survila U. L.
Synthesis of new imidacloprid structural analogues from 6-methoxynicotinic aldehyde. pp. 66--69
Summary: Novel structural analogues of imidacloprid, the known insecticide, were prepared. The key intermediate for the synthesis of target compounds is 6-methoxynicotinic aldehyde.
BIOORGANIC CHEMISTRY
Sysa A. G., Kiselev P. A., Zhabinsky V. N., Khripach V. A.
The effect of natural 24-epybrassinolide, 28-homo-brassinolide and their synthetic (22S,23S-dihydroxy)-derivatives upon monooxygenase system of mammal liver cells. pp. 70--76
Summary: Potential ways of brassinosteroids' effect on mammal organisms, in particular, possibility of their direct influence on metabolic processes, have been estimated. It has been shown that side chain structure of brassinosteroids plays an important part in regulation of microsomal activity of mammal's liver cells. This provides the opportunity for directed modifying of natural compounds, in order to achieve necessary physiological effects. One of positive effects of such modification can be anticancerogenic activity of synthetic brassinosteroid analogues.
Lakhvich F. A., Litvinko N. M., Skorostetskaya L. A., Kuchuro S. V., Antonchik G. N., Gerlovsky D. O., Ogeyko N. G., Petrusevich I. I.
Activity of secretory phospholipase A2 during formation of several cyclohexane-1,3-diones' tautomeric forms. pp. 77--81
Summary: Cyclohexane-1,3-diones effect on phospholipase A2 (PLA2) activity toward phosphatidylcholine liposomes during pH change from 2.2 to 10.0 has been studied. Stimulation of initial lipolysis rate by cyclohexane-1,3-diones has been observed at all pH values within the above interval.
POLYMER CHEMISTRY
Yermalinskaya T. M., Bil'dyukevich A. V., Fen'ko L. A.
Membrane formation from vinylidene fluoride and tetrafluoroethylene co-polymer of varied molecular mass. pp. 82--86
Summary: The effect of molecular weight of tetrafluoroethelene and vinylidene difluoride (F42 brand) copolymer on the viscosity and optical properties of casting solutions, as well as permeability of membranes produced, have been studied and discussed in detail.
Prihazhayeva L. M., Polikarpov A. P., Shunkevich A. A.
The effect of bifunctional comonomers additives on chemical stability and water extracts oxidation sucseptibility of fibrous carboxylic cationite FIBAN K-4. pp. 87--90
Summary: The chemical stability of fibrous carboxylic cationite FIBAN K-4 synthesized by graft-copolymerization of acrylic acid and 0.5 mol.% (from monomer) of bifunctional comonomers (divinylbenzene, ethylene glycol dimethacrylate, methylene bis-acrylamide) to polypropylene fibers has been studied. It has been demonstrated that addition of linking agents provides the opportunity to produce ion-exchange fibers, chemically stable in corrosive media (5 N NaOH, 5 N H2SO4, 10% H2O2). These fibers, unlike non-crosslinked FIBAN K-4 fibers, fit the sanitary requirements for filtering polymer materials allowed for drinking water purification.
TECHNICAL CHEMISTRY AND CHEMICAL TECHNOLOGY
Bambalov N. N., Smirnova V. V.
Physico-chemical properties of soluble humic compounds from valley peat. pp. 91--96
Summary: Humic acids have been extracted from valley peat by water, sodium chloride, sodium pyrophosphate, sodium hydrocar-bonate, sodium hydroxide, and their molecular-mass distribution, carboxylic and phenolic hydroxyl groups content, as well as substances hydrolysable by 2% hydrochloric acid, have been investigated.
Mozheyko F. F., Potkina T. N., Goncharik I. I., Voytenko A. I.
Acid-free technologies for processing of Belarusian phosphorites. pp. 97--104
Summary: The possibility of integrated processing for Belarusian phosphorite ores has been shown. Methods for phosphorite powder granulation and converting it into composite granular NPK fertilizers using various binding agents, have been investigated. Various grades of suspended NPK-fertilizers with wide range of useful substance content on the basis of phosphorite powder and salt solutions have been developed.
Zaitseva T. L.
Correlation between kind of peat and yield of triterpene compounds. pp. 105--107
Summary: The extractive substances from herb of low-bog and raised bog peat have been isolated by extraction with water-alcohol solvent. It has been shown that the yield of extracts and triterpenoid content depends on peat type or its botanic structure. The greatest amount of extractive substances has been obtained from riding peat of Eriophorum sp. group (up to 5.0%, the yield increased with increasing parts of Eriophorum sp. from 35 to 55% in peat botanic structure). The lowest amount (0.6%) has been extracted from reed peat. It has been shown that no triterpenoids can be extracted with water-alcohol solvent from lowland peat. The maximum amount of these compounds is typical for pine -- cotton grass and cotton grass -- sphagnum peat with decomposition degree of 35%.
Levitsky I. A., Papko L. F., Zayats N. I.
Regularities in migration of harmful compounds from colored glass coatings. pp. 108--111
Summary: Regularities of boron, aluminium and d-elements (Cr, Mn, Cu, Co) ions from colored glaze coatings into 4% acetic acid solution have been established. It has been shown that introduction of d-element oxides increases boron migration. Low levels of harmful species migration are typical for Mn- and Cu-containing glaze coatings.
Pisch I. V., Kris'ko L. Ya., Popov P. Yu.
The effect of high molecular weight flocculants upon rheologic properties and processing characteristics of polymineral clay. pp. 112--115
Summary: The results of the investigation on the effect of electrolyte component on reological and technological properties of polymineral clay from "Shebrin" deposit are reported. Certain additives cause increase in the size of suspension particles, and this opens up the opportunity to increase plasticity of clay, mechanical durability of products, and to shorten drying time.
Gurbanov A. N.
Investigation of byproducts as gas hydrate formation inhibitors. pp. 116--118
Summary: The main purpose of natural and associated gas preparation for transportation is to provide their normal transportation by field and main gas pipelines. Developed gas and gas-condesate fields, containing great amount of various aggressive admixtures and mineral salts, require efficient natural gas preparation for further transportation. Therefore, more efficient and cheap inhibitor of complex action preventing the hydrate formation, corrosion and salt deposition in the system, should be developed on the basis of petrochemical products of the republic. Main physical and chemical characteristics of the inhibitor composition, depending upon the proportion of components, have been determined under laboratory conditions, and new inhibitor composition has been proposed, on the basis of propylene glycol production by-products. The technology of its application for gas field treatment has been developed.
SCIENTISTS OF BELARUS
Krut'ko N.P., Bildyukevich A. V., Egiazarov Yu.G. et al.
Boris Vasil'evich Erofeev (To the 100th anniversary). pp. 119--120
Click here to read this article in Russian (Win1251)
Rakhmanov S.K., Agabekov V.Ye., Kaputskii F.N. et al.
Nikolai Pavlovich Krut'ko (To the 60th anniversary). pp. 121--123
Click here to read this article in Russian (Win1251)
/ Publications / Scientific Journals / Back to Top of Page
Designed and maintained by Dr. Nikolai N. Kostyukovich. Last updated: August 21, 2009
Created with assistance of Dr. Ignatii I. Korsak
Copyright © 2009 The National Academy of Sciences of Belarus
Copyright © 2009 The Belaruskaya Navuka Publishing House
