Весці Нац. акадэміі навук Беларусі. Сер. хім. навук, 2005, No.4
/ Выданні акадэміі / Навуковыя часопісы
Весці Нац. акадэміі навук Беларусі. Сер. хім. навук, 2005, No.4
| Весці Нацыянальнай акадэміі навук Беларусі
СЕРЫЯ ХІМІЧНЫХ НАВУКВыдавец: Беларуская навука, Мінск, Рэспубліка Беларусь |
Нумар 4, 2005
ЗМЕСТ
АНАЛІТЫЧНАЯ ХІМІЯ
Pomelenok E. V., Egorov V. V., Rakhman'ko E. M., Akayeu Y. B.
The effect of hexyl p-trifluoroacetylbcnzoate upon selectivity of anion-exchange extraction by higher quaternary ammonium salts. pp. 5--9
Summary: The effect of hexyl 4-trifluoroacetylbenzoate (hexyl ester, HE) additives upon chloride and sulfate anion-exchange extraction by toluene solutions of lipophilic quaternary ammonium salts (QAS) in picrate form with varying steric accessibility of their exchange center, has been studied. Effective exchange constants for picrate-chloride and picrate-sulfate exchange have been determined. Solvation numbers and solvation constants of the corresponding QAS chlorides and sulfates by HE have been calculated. It has been found that solvation numbers depend only upon anion nature while solvation constants regularly decrease with improvement of QAS exchange center steric accessibility. The results obtained are explained by peculiarities of association of free and HE-solvated anions with QAS cations. It has been shown that anion-exchange selectivity can be efficiently controlled by varying of QAS cation steric accessibility and HE concentration.
КАЛОІДНАЯ ХІМІЯ
Komarov V. S., Repina N. S. †, Rat'ko A. I.
The effect of preparation condition on carbon-mineral adsorbent properties. pp. 10--12
Summary: A new method for obtaining carbon-mineral adsorbents by alkaline activation of natural aluminosilicate in presence of lignin has been developed. It has been shown that after treatment at 240 °C adsorbents acquire liophobic surface characteristics. When 40wt% of lignin is introduced into samples, the adsorbents obtained possess sorption properties similar to those of KU-1 carbon.
It has been concluded that alkaline activation of meta-kaolin produces adsorbents with better structural parameters than those obtained by alkaline activation of montmorillonite.
Komarov V. S., Seredyuk L. I., Rat'ko A. I.
Organomineral and carbon-mineral adsorbents based on methacaoline. pp. 13--17
Summary: Adsorption and structural properties of organic- and carbon-mineral adsorbents obtained by alkaline activation of meta-kaolin followed by hydroxide precipitation in presence of organic modifiers, such as starch and gelatin at various concentrations, have been studied. It has been shown that organic-mineral samples possess high sorption capacity and large specific surface. Thermally treated samples, for several reasons discussed in the paper in detail, are much worse by those characteristics, but they have carbon-like selectivity and can be used instead of carbons in many kinds of sorption processes.
ФІЗІЧНАЯ ХІМІЯ
Gavrilyuk I. V., Kuvaeva Z. I.
Regularities of phenylalanine extraction from water-salt solutions by a sulfoextractant. pp. 18--20
Summary: Extraction of phenylalanine from water-salt solutions by a liquid sulfosurfactant -- dinonylnaphtalene sulfonic acid heptane solution -- in wide pH and amino acid concentration range has been investigated. Contribution of separate components (ion-exchanged cation and zwitterion absorbed in non-exchange fashion) to extraction total has been calculated. The determining role of the ion-exchange mechanism in Phe extraction has been demonstrated. The amount of Phe± zwitterion absorbed in non-exchange fashion is insignificant and virtually constant in acid pH range.
Fen'ko L. A., Bil'dyukevich A. V.
Viscosity of poly-e-caproamidc solutions in dimethylacetamide containing lithium chloride. pp. 21--24
Summary: The effect of solvent composition upon viscosity of dilute and moderately concentrated polycaproamide solutions in dimelhyl-acetamide containing lithium chloride has been studied. It has been found that with increase of LiCl content in binary solvent, characteristic viscosity rises and the Haggins constant decreases, due to improvement of solvent thermodynamic quality. Compression ratios for rnacromolecules have been calculated and critical concentrations have been determined. Experimental data on relationships between determining factors and viscosity have been summarized.
Rogachev A. V., Yarmolenko M. A., Rogachev A. A.
Formation and properties of thin-film coatings from products of polyethylene dispersion. pp. 25--28
Summary: It has been shown that plasma processing of volatile dispersion products and addition of dicumenyl peroxide to their mixture promote formation of disperse layers with better mechanical characteristics.
Stepanova L. I., Purovskaya O. G.
Electrodeposition of Ni-W and Ni-Mo alloys: regularities, microstructure and properties. pp. 29--34
Summary: Tungsten and molybdenum electrochemical co-deposition with nickel from mixed solutions has been studied. Regularities of the process, chemical and phase composition, and surface morphology have been compared for alloys obtained under various conditions. It has been shown that addition of a molybdenum salt to citrate solutions decreases deposition rate to a greater degree than that of a tungsten salt. The effect of ammonium ions upon deposition rate and composition of alloys have been analyzed. Conditions favoring inclusion of refractory metal oxides into alloy films have been discussed. It has been demonstrated that formation of tungsten oxides during precipitation of Ni-W alloys is promoted by high concentration ammonium ions, and that for molybdenum oxides promoting factors arc both absence and high concentration of ammonium ions, as well as high molybdate concentration.
Tsuber V. K., Kulak A. I., Krutsko E. N., Kopyl A. P.
Electrochemical deposition of calcium phosphate coatings on steel surface. pp. 35--38
Summary: The method for electrochemical deposition of calcium phosphate coatings onto stainless steel supports in aqueous NH4H2PO4--CaCl2 electrolytes under mild conditions (room temperature, current density 2 mA/cm2) has been proposed. With the use of XRD, FTIR and SEM techniques, the crystalline structure and composition of deposited coatings have been determined. It has been shown that deposits consist mainly of calcium hydrogen phosphate di-hydrate (brushite) CaHPO4 • 2H2O, a-tricalcium phosphate a-Ca3(PO4)2, calcium dihydrogen phosphate Ca(H2PO4)2 and hydroxyapatite Ca10(PO4)6(OH)2. The content of hydroxyapatite in the coatings increases with increasing elec-trodeposition time from 1 to 2.5 hours. The method developed in this study for electrodeposition of calcium phosphate coatings appears to be very promising for preparation of bioceramic coatings on the surface of steel medical implants.
АРГАНІЧНАЯ ХІМІЯ
Dikusar E. A., Kozlov N. G., Potkin V. I., Zelenkovskii V. M., Malama A. A., Dubovik S. V.
Synthesis of 4-hydroxy(alkyloyloxy, aryloyloxy)-3-methoxy(ethoxy)phenylmethylene-(2-carboxyphenyl)amines. pp. 39--46
Summary: By the reaction of vanillin, vanillal and their esters with 2-aminobenzoic acid in methanol, previously unknown azomethynes have been synthesized.
БІЯАРГАНІЧНАЯ ХІМІЯ
Piven N. V., Goncharik A. V., Shkumatova G. A., Pilatova N. L., Orlova E. E.
Immunofluoresccnt analysis of the major hustocompatibility complex molecular expression. pp. 47--51
Summary: Expression level of HLA -- A, B, C, and HLA -- DR on the surface of peripheral blood lymphocytes and the relationship of these parameters with content of thyroid hormones and proteins has been studied, using highly sensitive and specific immunofluorescence technique. The possibility of using the data obtained as a prognostic criterion of various thyroid gland diseases has been estimated.
Tarun E. I., Rubinov D. B., Metelitza D. I.
Kinetics of urease inhibition by polycarbonyl compounds. pp. 52--56
Summary: The comparative kinetic study of urease competitive inhibition by the 12 polycarbonyl compounds, including barbituric acid, its 5,5-diethyl derivative and cyclic di- and triketones, has been carried out in aqueous solution at 36°C and pH 4.95. It has been shown that inhibition constants Ki vary in wide range from 5.0 to 1170 µM. The most efficient inhibitors of soybean urease are barbituric acid (Ki = 5.0 µM) and two cyclic triketones (Ki = 10.4 µM). Elimination of b-dicarbonyl groups in cyclic triketones decreases sharply their inhibiting efficiency in urease hydrolysis of urea (Ki = 460 and 1170 µM, respectively).
ХІМІЯ ПАЛІМЕРАЎ
Budkuyte A. I., Barannikova T. I., Geller B. E.
The effect of acrilonitrile/2-acrylamide-2-methylpropanesulfonic acid statistic co-polymer composition upon their heterophase alkaline hydrolysis kinetics. pp. 57--63
Summary: The kinetics of heterophase alkaline hydrolysis of polyacrylonitrile fibers based on poly(acrylonitrile-co-acrylamide-2-methylpropanesulfonic acid) containing varied amounts of the second co-monomer, at 298 -- 338 K in 0.5 -- 1.5 M NaOH solutions has been studied. The apparent activation energy of this process has been estimated. Thermal properties of modified fibers have been studied by the differential scanning calorimetry method.
ГЕАХІМІЯ
Tolkachikova A. A.
Geochemical particularities of magmatic and ultrametamorphic rocks of the Bragin granulite massif. pp. 64--68
Summary: Geochemical particularities of metagabbro, quartz dioritc and granodiorite (Kopan' complex) as well plagioclase granite and migmatitic granite belonging to the Barsuki complex have been studied. A comparative analysis of the rocks studied and similar rocks from crystalline basement of Belarus and the Ukrainian shield has been performed, and their possible analogs have been determined. The study of granitoids has allowed to preliminary estimate their palaeogeodynamic environment and to make the conclusion that formation of granitoids happened in two stages under collision tectonic setting.
Ryabova L. N.
Geochemical characteristics of soil in Dnepr valley. pp. 69--75
Summary: Variations of geochemical indices determined in soil from eluvial (terraces), transeluvial (terrace slopes), transaccumulative (periterrace floodplain) and accumulative landscapes of Dnepr valley have been discussed.
Generalova V. A., Onoshko M. P.
Zinc and copper sorption by alluvial sediments. pp. 76--82
Summary: Adsorption of Zn2+ and Cu2+ by peat, limonite, clay, marl, warp, clay sand and loam has been studied. It has been shown that organic matter, clay and ferriferous minerals contribute differently to the sorption process.
ТЭХНІЧНАЯ ХІМІЯ І ХІМІЧНАЯ ТЭХНАЛОГІЯ
Krut'ko N. P., Markin A. D., Zhdanovich I. B., Rudakovskaya T. G., Dikhtiyevskaya L. V., Shevchuk V. V., Gorbachev A. S.
The effect of polyacrylamide on strength of potassium chloride grains. pp. 83--85
Summary: The effect of polyacrylamide water solutions on dynamic firmness and moisture resistance of potassium chloride grains during the improvement stage has been investigated.
Moskal'chuk L. N.
Using sapropels as adsorbents for reclaiming radionuclide contaminated soils. pp. 86--91
Summary: The results for experimental studies on behavior and distribution of 137Cs and 85Sr in solid-liquid system for freshwater lake sediments (sapropels) have been presented. The potential efficiency of sapropels as adsorbents for 137Cs and 85Sr with the purpose to reclaim the soils contaminated by radionuclides has been discussed. It has been shown that distribution of these radionuclides in solid-liquid system for sapropels is governed by the same laws as their distribution in soils and that experimental KD values can be quantitatively interpreted on the basis of parameters characterizing that distribution. This quantitative approach allows determining the potential efficiency of sapropels as radionuclide adsorbents for reclaiming radionuclide contaminated soils in Belarus.
Fleisher V. L., Lamotkin A. I., Lamotkin S. A.
Preparation of esters from rosin and amino alcohols. pp. 92--96
Summary: The conditions for tall oil and rosin esterification by amino alcohols (triethanolamine and monocthanolamine) have been determined. The effect of temperature and reagent ratio upon reaction duration has been established.
The effect of temperature on ester-amide ratio in the reaction of tall oil with monoethanolamine has been estimated using NMR spectroscopy.
Dite M. V., Bambalov N. N.
Effect of calcium cation concentration upon molecular mass distribution of humic acids. pp. 97--100
Summary: Aggregates of several molecules of humic acids are formed after addition of calcium ions to alkaline solution of peat humic acids if CaCl2 concentration is below the coagulation threshold.
Dasinyuk E. V., Zhukov V. K.
Non-regenerable sorption materials based on rapidly regenerated biomass. pp. 101--105
Summary: Sorption characteristics of rapid pyrolysis cokes prepared from American artichoke, sunflower, reed, willow and alder biomass has been studied. Possibility of obtaining cheap non-regenerable sorption materials from reed and willow, with sorption pore volume up to 0.1 cm3 • g-1 and specific surface about 100 m2 • g-1, for purification of sewage and technological water has been shown.
Chernaya N. V., Emello G. G., Lamotkin A. I.
The effect of basic aluminium salts on kinetics of modified tall oil emulsion rapid coagulation. pp. 106--112
Summary: Forms of aluminium hydroxy compounds present, content of which depends upon pH, affect kinetics of modified tall oil emulsion rapid coagulation significantly. Increasing aluminium sulfate solution pH from 1.95 to 5.30 increases "coagulation half-time" (t0) from 5.9 to 200.0 min and decreases enlarged particle content (N2, N3, ... , N11). It has been shown that presence of Al(H2O)5(OH)2+ and Al(H2O)4(OH)2+ instead of Al(H2O)63+ allows prolonging t0 from 5.9 to 27.3 min thus decreasing N2, N3, ... , N11 content.
АГЛЯДЫ
Litvinko N. M.
Inhibition of phospholipases A2 and C. pp. 113--124
Summary: The review on the role of enzyme inhibitors with varying chemical structure in the process of lipolysis by phospholipases A2 and C has been presented.
/ Выданні акадэміі / Навуковыя часопісы / Да пачатку старонкі
Распрацавана і падтрымліваецца Мікалаем М. Касцюковічам. Апошняе абнаўленне: 21 лістапада 2006 г.
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