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991.
Gert E. V. Zubets O. V. Shishonok M. V. Torgashov V. I. Kaputskii F. N. 《Russian Journal of Applied Chemistry》2003,76(4):595-599
The capability of cotton and wood cellulose in the common and microcrystalline forms to transform into cellulose-II under the action of 68-69% HNO3 was studied. The influence of temperature on the course of the phase transition in cellulose samples differing in origin and morphological structure and the dynamics of concomitant hydrolytic degradation and esterification of these materials were studied. 相似文献
992.
Makhmudova N. K. Kadyrova Z. Ch. Del'yaridi E. A. Sharipov Kh. T. 《Russian Journal of Coordination Chemistry》2003,29(2):93-98
The crystal structure of a complex of pyrazinecarbohydroxamic acid (PHA) with Mo(VI) has been studied by X-ray diffraction analysis. The PHA molecule enters the complex composition as the enole tautomeric form. The branched intermolecular bonds form a strong three-dimensional framework with cavities filled with water molecules. 相似文献
993.
Matsura V. A. Potekhin V. V. Platonov V. V. Tatsenko O. M. Ukraintsev V. B. Khokhryakov K. A. 《Russian Journal of General Chemistry》2003,73(12):1900-1903
Kinetic regularities of hydrogenation, oxidation with oxygen, and condensation of allyl alcohol in the presence of colloid palladium in situ were revealed. A mechanism of the reactions was proposed. 相似文献
994.
Lazareva T. G. Yakovleva O. V. Shinkareva E. V. 《Russian Journal of Applied Chemistry》2002,75(10):1692-1695
Rheological and electrical properties of polyvinyl alcohol solutions containing copper(II) and cobalt(II) chlorides are studied. Anomalous behavior of these properties is associated with complex formation, depending on the component ratio and temperature. 相似文献
995.
Sal'keeva L. K. Nurmagambetova M. T. Kurmanaliev O. Sh. 《Russian Journal of General Chemistry》2002,72(12):1955-1955
Russian Journal of General Chemistry - 相似文献
996.
Shul'ga Yu. M. Chernushevich I. V. Dzhardimalieva G. I. Roshchupkina O. S. Dodonov A. F. Pomogailo A. D. 《Russian Chemical Bulletin》1994,43(6):983-987
Russian Chemical Bulletin - The monomer [Cr3O(OCOCH=CH2)6]OH was produced by reaction of acrylic acid with fresh chromium hydroxide. This monomer was investigated by a number of physicochemical... 相似文献
997.
A. V. Borovkov Yu. N. Brusil'tsev A. O. Doroshenko 《Theoretical and Experimental Chemistry》1993,28(4):269-273
An investigation was carried out of the spectral-luminescent and acid-base properties at the stage of formation of the hydrogen bond and during the protonation of compounds with annelated aromatic and heterocyclic rings, obtained by introduction of bridging groups -CH=CH- (I), -CH=N- (II) and -CO-N(CH3)-(III) in the 4- and 2-positions of the molecules of 4-substituted derivatives of 2,5-diphenyloxazole. The nature of the reaction center was estabished, and an analysis was carried out of its sensitivity to the electronic influence of the substituents, and the reasons for the observed differences in the properties of compounds of various reaction series are discussed. A comparative analysis of the fluorescent properties of the neutral and protonated forms of the oxazole derivatives studied was made and the conclusion that the generation is possible of laser emission by the protonated forms of compounds of the reaction series (I) was confirmed.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, No. 4, pp. 343–349, July–August, 1992. 相似文献
998.
M. F. Budyka G. V. Zakharova O. D. Laukhina M. V. Alfimov 《Russian Chemical Bulletin》1992,41(9):1589-1596
The reaction of the photochemical synthesis of 2,7-dimethylacridine from di(para-tolyl)amine and bromoform was studied utilizing the method of microsecond impulse photolysis. The proposed new scheme for the formation of acridine assumes the recombination of the primary alkyl radicals at the nitrogen atom of the cation radical and/or the radical of the amine as the main route of the reaction. The data obtained indicate the common character of the nature of some intermediate stages and the structures of the intermediates in the photochemical formation of acridine compounds and triphenylmethane dyes from aromatic amines and halogenomethanes.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2044–2052, September, 1992. 相似文献
999.
O. A. Luk'yanov I. A. Savost'yanova V. P. Gorelik N. I. Shlykova V. A. Tartakovskii 《Russian Chemical Bulletin》1992,41(8):1395-1399
Silver and mercury salts of nitro compounds react with bromo- or chloroadamantanes with the formation of products of C- and/or O-alkylation, the ratio of which depends on the structure of the initial reactants. The direct experimental evidence of nitronic esters to be isomerized into nitro derivatives and of their role as intermediates in the formation of the nitro derivatives in the alkylation of nitro compounds has been presented for the first time.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiva Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1798–1803, August, 1992. 相似文献
1000.
S. Y. Cho O. D. Awh Y. J. Chung Y. S. Chung 《Journal of Radioanalytical and Nuclear Chemistry》1997,217(1):107-109
A nondestructive instrumental neutron activation technique was used to analyze human hair samples collected from people living in metropolitan and rural areas in Korea. Samples were also collected from factory workers and cancer patients. Hair from metropolitan area residents contain higher concentrations of Ca, Mg, Zn, Cu, Na, Br, Mn, I and S than rural area residents. Concentrations of I and S from cancer patients, Mg, Zn, Al, Na, Mn and As from glassware workers were relatively higher. The results show that the trace element concentrations of the hair are possibly related to the trace element concentrations in the body. 相似文献