СЕРИЯ ХИМИЧЕСКИХ НАУК
Издатель: Беларуская навука, Минск, Республика Беларусь
| Известия Национальной академии наук Беларуси СЕРИЯ ХИМИЧЕСКИХ НАУК Издатель: Беларуская навука, Минск, Республика Беларусь |
Summary: The nature of rare earth compound inclusions into the structure of crystalline CaSO4 • 2H2O has been investigated. Quantitative evaluation of this phenomenon based on results of comprehensive physical and chemical investigation of H3PO4 -- H2O and LaPO4 -- H3PO4 -- H2O systems has been performed.
Summary: A technique for chromium determination by cathode inversion voltammetry with a silver-modified carbon-glassceramic electrode has been developed. It has been found that the best background electrolyte for chromium determination is 0.1 M HNO3, and optimum potential for chromium accumulation as Ag2CrO4 is 200 mV. On the basis of data obtained, the tentative protocol for chromium determination in tap water and vine has been developed.
Rakhman'ko E. M., Zhylko V. U., Petrov A. Yu.
Extraction photometry determination of fatty carboxylic acid content in aqueous solutions and other objects. pp. 13--16
Summary: An extraction photometry technique for determination of fatty carboxylic acids in food oils, water and 1-chloronaphtalene has been proposed. The technique is based on the interaction of carboxylic acids with a cationic dye, safranine, at high pH, followed by extraction of the ion associate into an organic phase. Optimal composition of the organic phase and pH value has been selected. Foreign anion influence has been investigated. The technique proposed is highly sensitive and well reproducible, and it has been tested on various compounds.
Popova O. P., Poleshko G. D., Kuvaeva Z. I., Adamenko E. I., Silivonchik N. N.
HPLC application for ammo acid determination in blood serum. pp. 17--22
Summary: The conditions for chromatographic determination of free amino acids in blood serum by reversed-phase HPLC with absorbance detection in visible band (436 nm) on the PAN 16 PLUS column, using pre-column derivatization with DABS-C1 and gradient elution, have been worked out. The deproteinization was achieved by addition of chloric acid or methanol. The method allowed to determine 19 amino acid for 60 min (citrate buffer, pH = 6.5) or 21 amino acid for 65 min (phosphate buffer, pH = 7.2) in blood serum. It has been shown that eluates investigated (phosphate and citrate buffers) can be successfully used for identification of amino acid content deviations caused by various diseases. In particular, it is advisable to use citrate buffer for determination of blood serum amino acid content in liver cirrhosis patients. This eluate allows obtaining good separation for those amino acids that are cirrhosis markers (phenylalanine, tyrosine, tryptophan, leucine, isoleucine, valine).
Summary: Alkaline activation of hydromica minerals (glauconite, vermiculite and biotite) has been studied and it has been shown that these minerals in their natural state are very hard to activate, due to peculiarities of their crystal structure. Thermal treatment of samples improves their activation, especially when CaO + NaCl composition is used as an activating agent, followed by neutralization with sulfuric and phosphoric acid. The results have been interpreted in terms of composition and structure of the minerals studied.
Ostrovskaya E. F., Krut'ko N. P., Opanasenko O. N., Ovseenko L. V.
Adsorption of N-octadecyldimethylethyl-ammonium bromide on natural mineral materials. pp. 26--30
Summary: Interaction of N-octadecyldimethylethylammonium bromide with granite and mineral materials being part of pulverulent granite fractions has been investigated. Its adsorption characteristics were determined. It has been established that adsorption of N-octadecyldimethylethylammonium bromide is governed by the structure of minerals and change in the following order: montmorillonite > kaolin > dolomite > granite > quartzite. The above result is confirmed by calculated adsorption characteristics, as well as thermal analysis and IR spectroscopy data.
Goncharik I. I., Mozheiko F. F., Kulikova T. P.
Effect of heptyl alcohol upon stability, structure and flow characteristics of rapeseed oil-based emulsions. pp. 31--33
Summary: Conditions of emulsion formation in water -- rapeseed oil -- Na2CO3 -- heptyl alcohol system have been studied. At small alcohol concentrations flow characteristics of emulsions (Pk2, h) increase significantly.
Rat'ko A. I., Romanenkov V. E., Krupen'kina Zh. V.
Thermophysical properties of porous composite ceramics based on powdered components. pp. 34--37
Summary: The porous structure, mechanical and thermophysical properties of block composite high-porous ceramics have been studied. It has been found that effective heat conductivity of the synthesized material depends upon pore size and distribution, as well as skeleton heat conductivity. The prepared composite ceramics takes an intermediate position between porous ceramics prepared by metal powder agglomeration, and industrial adsorbents.
Summary: Chemical stability of the fibrous ion exchanger based on polyacrylonitrile co-polymer cross-linked by hydrazine hydrate, has been investigated. Possibility of its modification by phosphoric acid solutions with the purpose of sorption characteristics improvement and prospective application in air and water purification systems has been estimated.
Bedarik A. E., Alekseev N. A., Kulikov V. A., Chirkin A. A.
Sorption immobilization of ursodeoxycholic acid on anionites. pp. 42--45
Summary: Sorption immobilization of ursodeoxycholic acid (UDCA) on AV-17 and diethylaminoethylcellulose (DEC) anion exchangers has been studied. The sorption parameters for the above exchangers have been calculated and UDCA desorption into model media has been investigated. It has been found that UDCA immobilized on DEC possess more intensive and prolonged hepatoprotective and antioxidant effect.
Gaiduk A. P., Goroshko N. N., Gaiduk P. I.
Structural peculiarities of fine PbS films deposited on different substrates. pp. 46--50
Summary: Polycrystalline PbS films have been chemically deposited on different substrates (Si, SiO2, Ge, InP, GaAs). TEM, AFM and RBS techniques have been used for film characterization. Our study indicates a strong effect of the substrate on the film thickness, as well as on size and surface concentration of PbS nanocrystals. In general, we have deposited PbS nanociystals of average size varying from 20 to 100 nm on different substrates. It should be also noted that PbS nanoparticles occupy from 15 to 100% of area depending on substrate type.
Sviridova T. V., Stepanova L. I., Kazachenko V. P.
Electrochemically deposited composites based on nickel with incorporated particles of ultradispersed molibdenium trioxide. pp. 51--60
Summary: Incorporation of ultradispersed MoO3 (spherical particles 100--250 nm) into electrochemically deposited nickel films have been studied. Structural, morphological, tribotechnical and corrosion properties of the composite formed, have been investigated. It has been shown that co-deposition of nickel and dispersed molybdenum oxide (MoO3 1.5% wt.) increases hardness of the deposited films (from 3090 to 4950 MPa) and mechanical wear resistance (up to 10 times), improving at the same time their corrosion stability towards acids.
Omelchenko T. N., Soldatov V. S.
Preparative separation of leucine and alanine mixture on a fibrous sulfonic cation exchanger. pp. 61--64
Summary: Chromatographic separation of amino acids on strong-acid cation exchange fiber Fiban K-1 has been investigated.
Vengura A. V., Vrublevskaya O. N., Vorobyova T. N.
Character of gold reduction in tetrachloroaurate-citrate solutions. pp. 65--70
Summary: A new stable tetrachloroaurate-citrate alkaline solution for chemical gold plating on Ni-B and Ni-P substrates has been proposed and the character of gold reduction processes has been studied. It has been shown that gold plating in the above solution proceeds mainly by the mechanism of gold reduction with citrate. The dominant process is catalyzed by nickel and is accompanied by gold cementation and formation of colloidal gold particles and their coagulation. After the appropriate pretreatment procedure it is possible to produce gold films 0.1 µm thick, with good adhesion and attractive appearance. The total surface area covered by gold film formed from the solution is no less that 0.2 m2/l.
Summary: A method for synthesis of functionally substituted amine and phosphine salts of nicotinic acid has been described.
Bezborodov V. S., Kauhanka M. M., Lapanik V. I.
Synthesis of novel mesomorphic compounds containing two 2-isoxazoline rings. pp. 75--80
Summary: The synthesis of new 2-isoxazoline derivatives with two isoxazoline rings has been described. Among those, four substances possess liquid crystal properties. The mesomorphic characteristics of these compounds are given.
Popova L. A., Jurashevich N. Ya., Knizhnikov V. A.
Synthesis of 1,4-substituted 3,3-dichloro-2-azetidinones. pp. 81--83
Summary: Reactions of leucin methyl ether with benzaldehyde derivatives leads to formation of the corresponding azomethynes (CH3)2CHCH2CH(COOCH3)N = CHR. 3,3-Trichloroazetidinones have been obtained by the reaction of the above azomethynes with trichloroacetyl chloride and subsequent reaction mixture treatment with triphenylphosphine. Structures of the compounds obtained have been confirmed by IR, NMR 'H spectra and elemental analysis.
Summary: Efficiency of extracellular P. piceum F-648 catalase and horseradish peroxidase binding with various co-precipitated and coal-mineral adsorbents including calcium, aluminum, magnesium and zinc phosphates and hydroxides. It has been shown that Ca3(PO4)2, oxyapatite, Ca3(PO4)2 + Mg(OH)2 (1:1), AlPO4 + Ca3(PO4)2 (1:3), Ca3(PO4)2 + coal (1-3:1), AlPO4 + coal (1:2) and Mg(OH)2 + coal (3.3:1) can be effectively used for catalase immobilization and its isolation from culture broth of Penicillium piceum F-648. The above adsorbents only poorly bind horseradish peroxidase in water, while basic alumina is an effective adsorbent for this enzyme.
Chemuha O. N.
Preparation and properties of human thyroid peroxidase immunoreactive recombinant fragment. pp. 92--97
Summary: The heterological expression system for a thyroid peroxidase recombinant fragment (rfTPO) have been developed, and conditions for rfTPO solubilization have been optimized. The immunoreactive rfTPO was purified by immunoaffinity chroma-tography. The obtained rfTPO was compared with native thyroid peroxidase (nTPO) by enzyme linked immunosorbent assay using autoantibodies and monoclonal antibodies to nTPO.
Summary: For the first time, widespread development of highly mineralized groundwaters and brines in the most ancient rocks of Belarus (high Proterozoic sedimentary formations and Archaean -- low Proterozoic crystalline basal rocks) has been established. The origin of high saline content in underground waters is not connected with surface pond evaporative concentration processes. The geochemical profile of brines makes it possible to consider them highly transformed ancient residual water condensates formed in heat metamorphism of primary sedimentary rocks under amphibolite and epidote-amphibolite phase.
Summary: A possibility of obtaining humic preparations with known physical and chemical characteristics has been studied. The solubility of HA fractions has been shown to result in increase of carboxylic and phenol function content on the surface of humic powdered sorbents. The process of organomineral HA complex formation starts when critical concentration of heavy metal ions in solution is reached.
Rudakovskaya T. G., Zhdanovich I. B., Shevchuk V. V., Rat'ko A. I., Minin A. V.
Technology of concrete treatment by impregnation compositions. pp. 114--117
Summary: The optimum technological parameters for concrete treatment by impregnating composition have been determined in order to attain their most efficient utilization for pavement impregnation.
Pishch I. V., Supichenko G. N., Kirdyashkina N. A., Martsynkyan S. A.
Corrosion stability of ceramic materials towards mineral acids. pp. 118--120
Summary: Chemical durability of ceramic materials synthesized at various temperatures, towards sulfuric, hydrochloric and nitric acid has been investigated. Influence of chemical and phase composition on chemical durability has been determined, the correlation between acid concentration and time and temperature factors in the process of ceramic destruction has been revealed.