СЕРИЯ ХИМИЧЕСКИХ НАУК
Издатель: Беларуская навука, Минск, Республика Беларусь
| Известия Национальной академии наук Беларуси СЕРИЯ ХИМИЧЕСКИХ НАУК Издатель: Беларуская навука, Минск, Республика Беларусь |
Summary: By means of dialysis and potentiometry the one-component and binary aqueous solutions containing Cu2+ and Sc3+ cations have been investigated. The diagram of distribution of different cationic species has been obtained and the mechanism of hydroxo polymer formation has been proposed. The calculated values of hydrolysis activation energy support the preferential formation of heteronuclear hydroxo complexes.
Murashkevich A. N., Vashina V. G., Zharskii I. M.
Structural-sorption properties of films of SiO2. pp. 10--16
Summary: The porosity and structural properties of thin SiO2 films obtained by the sol-gel method were studied by the electro-chemical method, dye adsorption and on an electron microscope with a X-ray analyser.
Gorbunova V. A., Novikov G. I., Gamanovich N. M.
Synthesis of АВО3-materials for electrochemical application using lanthanide concentrates. pp. 17--22
Summary: A method to synthesize novel ABO3-group materials with lower cost than the conventional ones based on some doped manganites, chromite-manganites and cobaltites of mixed REEs of cerium group was proposed (using raw material lanthanide concentrates of the industrial type including the wastes) which are promising for high temperature and other electrochemical devices. The various physical-chemical characteristics of these multi-oxide materials as well as their structure parameters were established.
Summary: Kinetic of electrolyte coagulation of synthetic latexes in water-fiber solutions depend on the type and expense of the surfuctant used as a colloidal-chemical regulator. This process influents on the properties of paper and board obtained,
Pisch I. V., Kirdyashkina N. A., Muravskaya L. V.
Influence of electrolyte on reological properties of clays. pp. 27--29
Summary: The results of influence of such dilutions as sulphalignine, lignopole, soda on properties of fusible and refractory clays have been presented.
Summary: The conception of paramagnetism appearance of oil-dilutable surfactants which takes into account the principal role of synergetic effect of the aromatic rings and hydrogen bonds interaction explains the correlation between the EPR signal intensity and parameters and surfuctant efficiency. It has been found that normal high molecular hydrocarbons have the best protective properties among insulating inhibitors; the effective adsorption-chemosorption inhibitors have the definite interval of the EPR spectra intensity and parameters. The results obtained allow using IR and EPR-spectroscopy for preliminary selection of oil-dilutable surfactants.
Kol'nenkov V. P.
Fulfillment of the selectivity series of definite trend in fourionic ionexchange equilibria. pp. 38--43
Summary: The dependence of selectivity series such as T4 >T3 >T2 >T1 and the like on fourionic composition and pair equilibrium coefficients has been investigated, while Ti being the distribution coefficient for the i-th ion expressed in terms of mole fractions (i = 1,2,3,4). These dependencies were described as certain correlations between the pair equilibrium coefficients as well as fixed composition fields on the tetrahedral diagram.
Gromak V. V., Avakyan V. G., Pashkovskii F. S., Lakhvich O. F., Budnikova M. V.
Calculation of tautomeric properties and energies of intramolecular H-bonds in a-formyl derivatives of five-membered cyclic b-dicarbonyl compounds by the methods AM1 and PM3. pp. 44--48
Summary: Using the semiempirical methods AM1 and PM3 the energies of intramolecular H-bonds in enolic tautomers of a-formyl derivatives of five-membered carbo- and heterocyclic b-dicarbonyl compounds have been calculated and relative thermodynamic stabilities of the tautomers have been estimated. It has been shown that currently existing theoretical and experimental methods for determinating the absolute values of H-bonds energy in enolic derivatives of b-diketones and b,b'-triketones can diminish the real energy values by 0.9--5.0 kcal•mol-1. It has been shown that in vapour phase (ideal gas approximation) all the b,b'-tricarbonyl compounds studied exist predominantly as exoenolic tautomers.
Komarov V. S., Repina N. S., Rat'ko A. I.
Sorption and structural properties of three- and four-porous adsorbents with different composition. pp. 49--53
Summary: The adsorbent specimens with three- and four-porous structures presented as homogeneous hydroxides with different structures as well as hydroxides of different nature, sizes and particles forms were synthesized and their adsorption-structural properties were investigated. The influence of thermal treatment on sorption properties, structure of the specimens and features of pore-size distribution were studied. The mechanism of porous structure formation of above materials and features of its changing as a function of the hydroxides mixtures composition are discussed.
Byk T. V., Tsybul'skaya L. S., Gaevskaya T. V.
Electrochemical deposition of films of zinc-nickel alloys with different composition from water solutions. pp. 54--58
Summary: The process of electrochemical deposition of zinc and nickel from simple (weak-acid chloride (pH 4.5۪.2) and complex (ammonical (pH 6.3۪.2) and ammonical-pyrophosphate (pH 7.5۪.2) electrolytes has been investigated. It has been established that the process of zinc -- nickel alloy electrodeposition from polyligand ammonical-pyrophosphate solution essentially differs from the process proceeding from ammonical and chloride solutions. For the first electrolyte the Zn(II)/Ni(II) ratio in the solution is equal to the Zn(II)/Ni(II) ratio in the alloy (the case of normal co-deposition of the alloy), and for two others the Zn(II)/Ni(II) ratio in the solution is a lot more than that in the alloy (the case of anomalous co-deposition of the alloy).
Summary: The process of furfural formation under the action of microwave radiation has been studied. The influence of the microwave treatment conditions and sulfuric acid concentration on dehydration of xylose in water solutions and furfural formation has been investigated.
Voitekhovach S. V., Gaponik P. N., Ivashkevich O. A.
Quaternizaton of 1-aryltetrazoles in perchloric acid media. pp. 62--65
Summary: 1-Aryltetrazoles were shown to quaternize with tert-butyl alcohol, isopropyl alcohol and 1-phenylethyl alcohol in perchloric acid media with formation of 1,3- and 1,4-disubstituted tetrazolium salts. Selectivity of quaternization depends on nature of substrate and alkylating agent, acidity of reaction media and duration of the reaction.
Summary: D, L-Asparagine monohydrate has been obtained by interaction of maleic anhydride and ammonium in water.
Andrianov A. M.
Conformation of the principal neutralizing determinant of the HIV-1 Thailand isolate. pp. 69--77
Summary: Using the earlier suggested method the conformation of the principal neutralizing determinant (PND) of the HIV-1 Thailand isolate (HIVThailand) has been determined in the terms of the NMR spectroscopy data. As the result of the study the conformations of the individual amino acid residues of the HIVThailand PND have been revealed and its secondary structure elements have been analysed. The most probable conformers of the fragment which forms the viral immunodominant epitope were computed. It is shown that the set of the simulated best-energy conformations compatible with the NMR data corresponds to the one derived earlier for the HIVMN PND and contains the structure observed in the crystal. The results obtained are discussed in connection with the literature data on the structure of the HIV-1 PND.
Budnikova L. P., Survilo L. I., Eremin A. N.
Stabilization of diluted solution of peroxidase with monoclonal antibodies against human thyreotropine. pp. 78--81
Summary: Stabilization of diluted water solutions of conjugates of horseradish peroxidase with monoclonal antibodies against thyreotropic hormone is achived in the systems prepared using salts (MgSO4, NaCl and Na2SO3), poliols (glycerol, maltose and sucrose), BSA, triton X-100 and antibacterium agents (ethanol, caton and merthiolate). The system including 50 mM tris-HCl buffer, pH 7.6, 0.2 mg/ml BSA and 0.1% caton is the most perspective for practical purposes.
Kiseleva E. P., Vashkevich I. I., Pryadko A. G., Levchenko V. K., Matveentsev V. D., Lavretskaya E. I., Sviridov O. V., Nevskaya L. L., Kosheleva M. I., Schitikov B. D., Kovalenko Yu. D., Kamyshnikov V. S.
Biochemical aspects of development of immunoferment kits: diagnostic complex for assay of alpha-fetoprotein, chorionic gonadotropin and estriol. pp. 82--88
Summary: Using the same methodology, the kits for an enzyme immunoassay of alpha-fetoprotein, chorionic gonadotropin and estriol have been developed and tested. The construction of the kits is based on the use of harmless tetramethylbenzidine as a chromogen in peroxidase reaction and on biospecific immobilization of antibodies onto the wells of breakable microplates. The whole analysis may be carried out during a working day. The analytical data correspond to clinical characteristics of a disease and have a variation coefficient not higher than 10%, linearity and recovery in the range of 80--120% and a detection limit not higher than 50% of a diagnostic marker concentration in the first calibration sample.
Summary: The effect of salt-containing clay powder modification by drying oil on properties of filled polyethylene has been studied.
Bodkova N. M., Barantseva S. E., Galaburda A. I.
Preparation of durable petrositalls on the basis of diabases of Republic of Belarus. pp. 92--95
Summary: Possible application of rocks of Belarus for synthesis of glass ceramics with definite phase composition, which have high microsolidity, chemical durability and wear durability has been shown.
Schiglinskii V. S., Brasovskii I. I., Semenovich I. V., Samoilenko V. V., Saskovets V. V., Fedorov V. G., Borisyuk V. V.
Plant for regeneration of liquid ferruginous waste. pp. 96--98
Summary: The plant for processing exhausted etching sulphuric acid solution with production of iron vitriol commodity is offered. All fulfilled liquids are planed to be repeatedly used in a technological cycle. The principle of processing is based on cooling of a initial solution in crystallizers with sedimentation of iron vitriol crystals and them separation by centrifuges. The control and automatic systems supervised by a personal computer exerts semi-automatic control over the technological cycle of etching solution regeneration besides collection and computer processing of the data operation of the technological equipment.
Bogdanovich I. A., Kuz'menkov M. I.
Process of supergypsum preparation from synthetic CaSO4 • 2H2O. pp. 99--104
Summary: On the basis of the systematic investigation of some technological parameters at the stage of obtaining highly strengthened binding (supergypsum) from synthetic CaSO4 • 2H2O the optimum indices which provide to obtain a-halfhydrate calcium sulfate with the highest strength properties are found. The importance of the technological factors decreases in the following way: stream pressure in the autoclave, time of isothermal exposure, compacting pressure of original powder, drying temperature for steamed briquettes.
Martsul V. N., Abadi M., Lipik V. T.
Gaseous products of pyrolysis of polymer compositions based on polyvinylchloride. pp. 105--109
Summary: The results is submitted on the composition of gaseous products of polyvinyl chloride (PVC) pyrolysis in the range of 200--800 °C. A mechanism of the products formation is offered. The data is received on the influence of the composition of polymers based on PVC on the pyrolysis products yields. The substances making the main mass part of gaseous products is established.
Karpunin I. I.
About structure of flax lignin. pp. 110--112
Summary: Possible formulae of structure of bast lignins and flax wood based on the investigation results and literature data are proposed.
Stefanyuk I. V., Tavgen V. V., Shkadretsova V. G., Oleinikova E. L., Markevich V. G.
Catalytic activity of oxides of metals of variable valency and spinels in self-cleaning coatings. pp. 113--116
Summary: For the purpose of obtaining self-cleaning coatings for roast boxes of kitchen plates the ability of glassyceramical compositions to decompose vegetable fats at heating up to 300 °С was investigated. It was established, that in compositions with glass binder the oxides of manganese and copper, chromium and copper display catalytic properties at smaller temperatures, than previously synthesized spinels do and, accordingly, glassyoxide compositions are characterized by the large factor of fats decomposition.
Summary: Carcinogenic compound N-nitrosodimethylamine was detected for the first time in milk from the Gomel region of Belarus using the method of thin layer chromatography. Its level was 7-12 time higher than that well known from literature. It is necessary to control the NDMA concentration in milk from the regions of Belarus.