(Vestsi Akademii Navuk Belarusi)
SERIES OF CHEMICAL SCIENCES
Published by The Belaruskaya Navuka Publishing House, Minsk, Republic of Belarus
| Proceedings of the Academy of Sciences of Belarus (Vestsi Akademii Navuk Belarusi) SERIES OF CHEMICAL SCIENCES Published by The Belaruskaya Navuka Publishing House, Minsk, Republic of Belarus |
Summary: Chemically pure nitrogen has been found to interact vigorously with a solid lithium at a room temperature. An azotization rate increases discontinuously due to self-heating of the reaction mixture. To control the azotization process one should coordinate a nitrogen flow rate with heat extraction from the reaction mixture.
Summary: The effect of cation nature of the higher quaternary ammonium salt (QAS) and neutral transmitter of trifluorineacetyl derivative type on anion-exchange extraction of carbonate-, sulfate- and oxalate-onions has been studied in the system of toluene solution of the extractant -- water solution of the salt. Charge distribution on atoms of the anions extracted and extractants as well as their interatomic distances have been calculated by quantum chemical method. A correlation has been considered of extraction ability of QAS cation and extractability of the bivalent anion with geometric parameters of these particles and charge distribution on their atoms. The data obtained give a possibility to suggest a structure of ion associates formed by the bivalent anions and QAS cations.
Summary: A method of grafting efficiency determination for functional oxygencontaining groups (carboxylic, anhydrates) grafted to polyolefine macromolecules is described on LDPE example. The method is based on liquid extraction of a nongrafted portion from film samples followed by a comparison of spectra] characteristics of the samples before and after extraction. It has been shown that extraction should not be carried out in an aqueous medium due to oxidation of macromolecules in water resulting in carbonyl group accumulation in a bulk of the polymer.
Kuvaeva Z. I.
Physico-chemical and extraction properties of a solution of the higher alkylnaphthalene sulfonic acids. pp. 20--35
Summary: Physico-chemical and extraction properties of alkylnaphthalene sulfonic acids (ANSA) have been reviewed. A critical concentration of association, a degree of association, a size and a form of associates have been determined. Main dependences of ANSA interaction with simple inorganic cations and amino acids have been determined. Possible fields of ANSA application have been defined.
Liopo V. A., Voyna V. V., Shkadarevich A. P.
Structure peculiarities investigation of silicon glasses with different additives by X-ray powder diffractometry. pp. 36--42
Summary: Silicon glasses with different additives have been investigated by X-ray powder diffractometry. Positions and intensities of selective reflexes and total X-ray scattering modulations were analysed. A correlation has been revealed between sizes of the doping atoms and characteristics of selective reflexes and maximal of atomic density functions.
Kovalevskaya T. I.
On peculiarities of IR absorption spectra of nitrobenzene thin layers in an electric field. pp. 43--45
Summary: IR absorption spectra of nitrobenzene (NB) thin layers in an electric field have been studied. A decreasing intensity of CNO2 group absorption bands has been observed due to orientation of NB molecules.
Brazovskii I. I., Trubnikov V. P.
Kinetics of NO2 -- NO mixture dissociation under nuclear irradiation. pp. 46--50
Summary: Kinetics of NO2 -- NO mixture dissociation under n-, g-nuclear irradiation has been investiged in the temperature range from 200 to 300°C at 2 MPa and NO concentration up to 60 % wt. Radiation-chemical yields of N2 and N2O have been determined based on the experimental data. Kinetic peculiarities of N2 and N2O formation in experiment have been shown to be explained in terms of mathematical model of radiation-thermal decomposition of nitrogen dioxide.
Omelchenko T. N., Lubliner I. P., Elinson I. S., Martinovich V. I.
Sorption of heavy metals ions on phosphoro-acidic cationite. pp. 51--55
Summary: Sorption of ions of copper and other metals from aqueous solutions by cationite KF-1 prepared by phosphorylation of a nature product (flax boon) has been studied both under static and dynamic conditions. Extraction selectivity of Cu2+ and other ions from water solutions has been shown to depend on pH of the solution. The material is stable in cycles of sorption -- acidic regeneration.
Kaputskii F. N., Bashmakov I. A., Grigor'eva I. M., Samuilov V. A., Govor L. V., Butylina I. B., Solov'eva L. V., Ksenevich V. K.
Thin layer carbon networks: preparation and electrical properties. pp. 56--60
Summary: Low dimensional carbon networks have been prepared and their electrical properties have been investigated. Non-linear and stepwise volt-ampere characteristics of such structures could to be explained in terms of a model of dynamic random resistor network provided a strong local field exists.
Kovalenko N. A., Petkevich T. S., Egiazarov Yu. G.
Effect of titanium dioxide modification by niobium on a state of supported palladium and its activity in CO oxidation. pp. 61--65
Summary: A supported metal in the promoted paladium-titania catalysts shows an enhanced reduction ability due to electron density shift from Ti3+ ions formed in TiO2 promoted by Nb5 ions to palladium particles. A change of palladium electronic state manifests itself in increasing content of weak-bonded forms of adsorbed CO and oxygen, this fact facilitates increase of a catalytic activity of the modified catalyst in CO oxidation.
Komarov V. S., Repina N. S., Kosobutskaya N. F.
Effect of sublimated drying of some hydrogels on their structure parameters. pp. 66--70
Summary: Effect of sublimated drying and conditions of hydroxide production on a mean size of their elementary particles and structure parameters of the adsorbents prepared have been studied. A sample sorption volume (Vs), a particle diameter (D) have been shown to increase with concentration of salt solution while a specific surface (Ssp) decreases. Precipitation of hydroxides by pouring of the salt solution to the precipitator leads to increase of Ssp, and decrease of Vs and D. The results obtained have been interpreted and a synthesis way of hydroxides with ultra dispersed particles has been outlined.
Komarov V. S., Repina N. S., Kosobutskaya N. F., Karpinchik E. V., Dolgorukov B. A.
Structure parameters of adsorbents depending on a dispersity of their particles. pp. 71--75
Summary: Adsorption-structural properties of aluminium hydroxide samples depending on conditions of their production have been studied. Washing of Al(OH)3 with alcohol and drying in a microwave oven has been shown to promote sorption capacity increase, while a size of its elementary particles being unchanged. A particle size for the samples synthesized from methanol is about half as large as that for samples produced from water medium. The results obtained have been analyzed and a synthesis ways of materials with ultra dispersed particles have been outlined.
Senkov G. M., Nikitina A. M., Gorbatsevich M. F., Sominskii S. D.
Effect of sodium ions on a catalytic activity and state of platinum in alumoplatinum catalyst modified by dysprosium and chromium. pp. 76--79
Summary: Effect of Na+ ions on a catalytic activity of Pt/Al2O3, catalyst and on electronic state of platinum has been investigated. Na+ ions have been shown to promote an increase of electron density of Pt particles and a decrease of acidic centre activity of Al2O3 surface.
Summary: An optimization of N1-substituted tetrazoles synthesis from primary amines, triethylorthoformate and sodium azide has been carried out by an example of monoethanolamine. Optimal reaction conditions have been shown to be the following: a temperature is » 60°C, amine : orthoether : NaN3 : CH3COOH ratio is 1:3:1.1:8. The method elaborated was extended to a number of novel amines.
Lakhvich F. A., Sokolov S. N., Stanishevskii L. S.
Synthesis and stereochemistry of 3-hydroxy-phenylaminopiperidines and their derivatives. pp. 85--89
Summary: Diastereoisomeric 3-hydroxy-4-phenylaminopiperidines and their derivatives as fentanyl and corfentanyl analogues have been synthesized from 3-hydroxypiperedin-4-ones. Structure and configuration of the substances obtained have been confirmed by means of IR, NMR, 1H and 13C spectroscopy.
Summary: The synthesis of new 13,15-isoxazoloprostanoids have been realized as a result of a reaction sequence including nitromethane 1,4-addition to 2-(w-carbmethoxyhexy!)-2-cyclopentene-l-one, nitrile oxide generation from nitromethyl cyclopentane derivative followed by its 1,3-cyclization to halogenephenoxalken(yn)es. Some transformations of these compounds under reductive agents have been studied.
Sokolov Yu. A.
Comparative analysis of the results of quantum chemical MNDO and calculations of 8-azagon-1,3,5(10),9,(l l),13-pentaen-12,17-dione molecule. pp. 99--102
Summary: Quantum chemical MNDO and AMI calculations of some geometric and electronic characteristics for enaminone containing molecule from 8-azasteroid series have been carried out. The results calculated for enaminone bond length and dihedral angle differ insignificantly for both methods while essential distinctions in dipole moments and higher occupied molecular orbital energies are found out.
Survilo L. I., Budnikova L. P., Yudaev A. A.
Interaction of man thyroglobulin with concanavalin A-sepharose. pp. 103--107
Summary: The paper is devoted to a comparative investigation of a structure of thyroglobulin (Tg) carbohydrate component separated from tissue of intact and cancer thyroid glands. Interactions of several individual Tg samples from tissue of intact and cancer thyroid glands with concanavalin A-sepharose indicate to a difference in thyroglobulin carbohydrate components from the examined sources.
Summary: Technical and economical characteristics of installations for adsorption preparation of liquid paraffins according to "Parex" method could be substantially improved due to the process optimization. For that purpose a mathematical model may be used, which describes adequately adsorption and desorption of n-paraffin hydrocarbons and ammonia on a ceolyte 5A under conditions of an industrial absorber. The data are given on a mathematical description development permitting to describe rather accurately heat- and mass-exchange processed in industrial absorbers of "Parex" type.
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List of articles published in the journal "Vesti Akademii navuk Belarusi", Ser. khim. navuk, 1997. pp. 119--122
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