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1.
Journal of Structural Chemistry - Atomic and electronic structures of cyclic organosilicon compound 9,9,10,10-tetraethynyl-9,10-dihydrodisilaanthracene are studied by the density functional theory.... 相似文献
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The influence of the sequence of Cu and Pd introduction into zeolite matrice when preparing Cu, Pd-zeolite catalysts on their acidity and degree of metal reduction was studied. The mutual influence of Cu and Pd on their reducibility was analyzed. The selectivity of Cu, Pd-zeolite catalysts in conversion of synthesis gas to different products was elucidated. 相似文献
4.
I. S. Vasil’chenko T. E. Shestakova V. N. Ikorskii T. A. Kuz’menko V. G. Vlasenko L. N. Divaeva A. S. Burlov A. I. Uraev I. V. Pirog G. S. Borodkin P. B. Chepurnoi I. G. Borodkina O. A. Beletskii O. A. Karpov I. E. Uflyand A. D. Garnovskii 《Russian Journal of Coordination Chemistry》2007,33(3):176-183
Azomethine derivatives of 1-amino-2-thiobenzimidazole (H2L) were synthesized and studied by IR and 1H NMR spectroscopy. Thiobenzimidazoline tautomeric form of these compounds was found to predominate in a solid state and DMSO solution. Novel mono-and binuclear metal chelates M(HL)2 and M2L2 (M = Ni(II), Cu(II), Co(II), Zn(II), Cd(II)) were synthesized on the basis of H2L derivatives and their composition and structures were established from IR, 1H NMR, EXAFS, and magnetochemical data. The composition of coordination sphere was shown to produce no effect on ferromagnetic exchange in binuclear Cu(II) complexes. 相似文献
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V. G. Luchina V. S. Marevtsev I. Yu. Sychev T. Ya. Vlasenko Yu. D. Khamchukov M. I. Cherkashin 《Russian Chemical Bulletin》1992,41(1):72-76
The photochromic properties of 1,3,3-trimethylspiro[indolin-2,3-3H-anthraceno[2,1-b][1,4]-oxazine] (SAO) in solutions of different polarity [n-BuOH and petroleum ether (PETh)] were studied. It was established that the quantum yield of the photocoloration AB and the energy of activation of the thermal decolorization Ea in the PETh depend on the temperature; this is not the case in n-BuOH. The luminescence properties of SAO were investigated. It was found that the spectrum of the excitation of the luminescence in PETh depends on the temperature. These features, as well as the slower thermal decolorization of the colored form of SAO in PETh by comparison with the solutions in n-BuOH, are explained by the presence of dimers of the SAO molecules in nonpolar media in the temperature range investigated (77–300 K), whereas the SAO molecules already occur in the monomeric state at 150 K in the polar n-BuOH.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Branch of the Institute of the Physics of Solids and Semiconductors, Academy of Sciences of Belarus, 211177 Vitebsk. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 93–98, January, 1992. 相似文献
7.
V. G. Luchina I. Yu. Sychev V. S. Marevtsev T. Ya. Vlasenko Yu. D. Khamchukov M. I. Cherkashin 《Russian Chemical Bulletin》1992,41(1):77-82
The influence of temperature and concentration on the spectral polarization properties of the luminescence and absorption of molecules of the original form of photochromic spiroanthrooxazine (SAO) in petroleum ether and polyethylene was investigated. It was shown that the long-wave part of the absorption spectra of the molecules is formed by at least two -*-type electronic transitions, the oscillators of which are mutually orthogonal. It is suggested that the SAO molecules form dimers in nonpolar media through dipole-dipole interaction, and at high concentrations they also form higher associates. Dimers stable in the ground state dissociate when excited to the second electronic transition with a rate constant of 1012–1013 s–1.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Department of the Institute of Solid-State Physics and Semiconductors, Academy of Sciences of Belarus, 211177 Vitebsk. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 99–106, January, 1992. 相似文献
8.
V. M. Vlasenko V. Ya. Volfson S. A. Soloviev G. F. Kalapusha 《Reaction Kinetics and Catalysis Letters》1979,11(2):179-182
1,1- (AH) ([AH]=6,9 /, 50°C). AH Wi/WO
3=0,40±0,16.
The kinetics and oxidation products of 1,1-diethoxyethane (AH) ozonolysis have been investigated at [AH]=6.9 mol/l and 50 °C. The initiation efficiency of radical oxidation by ozone is Wi/WO 3=0.40±0.16.相似文献
9.
R. P. Gura V. M. Vlasenko V. A. Kuznetsov V. V. Raksha 《Theoretical and Experimental Chemistry》1985,21(3):324-329
Weight-space and IR spectroscopic methods have been used to investigate the reaction of NO and N2O with the surface of a copper-chromium oxide catalyst in the form of copper chromite with a 20% excess of Cr2O3. Comparisons have been made between the relative reactivities of the different oxides (NO, N2O, O2) in oxidation of the Cu+ and Cuo surface centers. The role of these centers in oxidation of CO by oxygen and by nitrogen oxides is discussed.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 3, pp. 338–343, May–June, 1985. 相似文献