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241.
A. N. Dmitrievskii A. A. Pribylov N. A. Skibitskaya L. A. Zekel’ A. P. Kubyshkin M. Ya. Shpirt 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(7):1099-1104
Isotherms of sorption of butane, propane, ethane, methane, and carbon dioxide on an asphaltene sample of known elemental composition were measured. The effect of the pressure and temperature on the shape the sorption isotherms for all the adsorption systems studied was examined. The values of the initial heat of sorption were determined and compared to the energies of interaction of the molecules with asphaltene. The results obtained suggest that asphaltene is a swellable amorphous sorbent. 相似文献
242.
Dzhemilev U. M. Ibragimov A. G. Khafizova L. O. Khalilov L. M. Vasil"ev Yu. V. Tomilov Yu. V. 《Russian Chemical Bulletin》2001,50(2):297-299
1-Ethyl-2,3-fullerenoaluminacyclopropanes (EtAl)n(2-C60) were synthesized by the reaction of fullerene C60 with an excess of EtAlCl2 in the presence of Mg and using Cp2TiCl2 as the catalyst in a THF--toluene solution at 20 °C. Deuterolysis of fullerenoaluminacyclopropanes afforded a mixture of deuteriofullerenes C60Dm, where m = 6--12. 相似文献
243.
A. I. Men’shikova T. G. Evseeva K. S. Inkin Yu. O. Skurkis S. S. Ivanchev 《Russian Journal of Applied Chemistry》2006,79(10):1660-1665
Emulsion copolymerization of methyl methacrylate and N-vinylformamide in the presence of azo initiators and dextran as a polymeric stabilizer was analyzed with the aim to prepare monodisperse polymer microspheres with a polyfunctional surface. Hydrolysis of comonomer units and cationic groups of the initiator residues in the surface layer of the particles to give amphoteric surfaces containing carboxy and amino groups was studied. The optimal conditions of formation of monodisperse microspheres with diameter varied in the 340–660 nm range and the conditions of their hydrolysis, which allow direct control of the amount and nature of functional groups on their surface, were found. 相似文献
244.
I. L. Glazko O. P. Gur’yanova S. V. Levanova S. A. Kozlova N. S. Neiman 《Russian Journal of Applied Chemistry》2005,78(6):950-954
A procedure was developed for preparing a plasticizer for polyvinyl chloride compounds from the fraction of dioxane alcohols. The main physicochemical properties of the new plasticizer were determined. Items prepared from formulations containing the new plasticizer were fabricated and tested in laboratory.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 6, 2005, pp. 972–976.Original Russian Text Copyright © 2005 by Glazko, Gur’yanova, Levanova, Kozlova, Neiman. 相似文献
245.
O. V. Firsova T. S. Dolgushina V. A. Polukeev E. M. Ioannisyan V. E. Zavodnik A. I. Stash V. K. Bel’skii V. A. Galishev 《Russian Journal of Organic Chemistry》2005,41(5):762-768
Reactions of thiazoline-2-thione with C,N-disubstituted nitrile imines were investigated. The reaction products are substituted 2-(1,3,4-thiadiazol-2-ylideneamino)ethanethiols and bis[2-(1,3,4-thiadiazol-2-ylideneamino)ethyl] disulfides. The reaction of thiazoline-2-thione with a double excess of nitrile imine did not considerably change the process route. The structure of compounds obtained was proved by X-ray diffraction analysis. A presumable scheme is given describing the formation of compounds obtained.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 776–782.Original Russian Text Copyright © 2005 by Firsova, Dolgushina, Polukeev, Ioannisyan, Zavodnik, Stash, Bel’skii, Galishev. 相似文献
246.
S. N. Pod’‘yachev S. V. Bukharov I. A. Litvinov V. I. Morozov A. T. Gubaidullin G. N. Nugumanova N. A. Mukmeneva 《Russian Journal of General Chemistry》2004,74(11):1651-1657
Copper(II) 3-(3,5-di-tert-butyl-4-hydroxybenzyl)acetylacetonate was prepared, and its molecular and crystal structure were determined by single crystal X-ray diffraction. There are two crystallographically independent molecules of the complex in the crystal. In the first molecule, the square planar coordination of Cu(II) is virtually ideal, and in the second molecule it is somewhat distorted. On the whole, the conformations of the independent molecules are similar. The ESR spectrum of the polycrystalline complex suggests magnetic coupling of the Cu atoms and magnetic ordering. In solution in coordination-inert toluene, heating increases the contribution of tetrahedral distortions. In ethanol, the solvent molecule additionally coordinates at the axial positions of the complex.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1775–1781.Original Russian Text Copyright © 2004 by Podyachev, Bukharov, Litvinov, Morozov, Gubaidullin, Nugumanova, Mukmeneva.This revised version was published online in April 2005 with a corrected cover date. 相似文献
247.
N. S. Shaglaeva O. V. Lebedeva Yu. N. Pozhidaev R. G. Sultangareev S. S. Bochkareva L. A. Es’kova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(3):335-338
Hybrid organoinorganic composites insoluble in water and organic solvents were prepared by the hydrolysis of tetraethoxysilane in the presence of poly-1-vinylpyrazole, poly-1-vinylimidazole, and poly-4-vinylpyridine. The composition of the composites was determined by the nature of the polymeric nitrogen base and hydrolysis conditions. The composites synthesized showed high sorption activity in the extraction of the [PdCl4]2?, [PtCl6]2?, and [AuCl4]? ions from hydrochloric acid solutions. 相似文献
248.
A. M. Genaev G. E. Sal’nikov V. G. Shubin 《Russian Journal of Organic Chemistry》2007,43(8):1134-1138
By DFT method energy barriers were calculated for carousel rearrangements of bicyclo[3.1.0]hexenyl, cyclobutenyl, and homotropylium cations. A plausible agreement between calculated and experimental findings was found. 相似文献
249.
A study was carried out on the composition and nature of the stabilizing additive on the activity of nickel-containing composites
based on zirconia in the methane steam conversion. The methane conversions were 91–99% on Ni/ZrO2(Y, Sc, Ce) at 700–800 °C. 相似文献
250.