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31.
After light irradiation of oil films on water surface the autoxidation process has been found to be of nonsteady auto-oscillatory character, which can be observed in rate oscillations of O2 absorption. Also recorded have been intensity oscillations of the EPR signal from the radical counter added into an oil sample. Complex dynamics of autoxidation can be due to an autocatalytic process involving the participation of peroxides accumulated in oil during photooxidation., , , , O2. , , . , , . 相似文献
32.
Conclusions On the basis of measurements of values of in liquid hydrocarbons, it has been shown that the path length before localization of a photoliberated electron increases with increasing mobility of the excess electron, from approximately 40 Å (methylcyclohexane) to 200 Å (isooctane). In a liquid with10–2 cm2/V·sec (methylcyclohexane, hexane), the localization takes place before or immediately after thermalization of the electron. In a liquid with>10–1 cm2/V·sec, the electron passes through the main part of its path before localization, being in thermal equilibrium with the medium.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2198–2203, October, 1985. 相似文献
33.
34.
V. M. Gul'ko N. F. Kolomiets B. V. Mikhailenko A. N. Paranich K. I. Yakovlev 《Russian Physics Journal》1991,34(11):977-980
An orbitron-type ion source is considered, with a cylindrical cathode and two wire anodes, operating at hydrogen pressures of 0.07–0.5 Pa with a firing voltage of 1–5 kV and mean discharge current of several mA. In pulsed high-current operation, a peak current of 25 A can be achieved with 2–3-sec pulses. The ion current is extracted through two longitudinal slits in the cathode and reaches 30% of the discharge current. The source performance is analyzed as a function of the gas pressure and geometrical parameters.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 35–39, November, 1991. 相似文献
35.
V. é. Zakhs I. P. Yakovlev N. A. Smorygo V. A. Gindin B. A. Ivin 《Chemistry of Heterocyclic Compounds》1987,23(3):325-332
1H,13C NMR, IR, and UV spectra have been studied for solutions of a number of potentially tautomeric 2-aryl-1,3-oxazine-4,6-diones and their 5-methyl substituted analogs with variation of substituent at the para position of the benzene ring, as well as compounds with a fixed structure that simulates possible tautomeric forms. The data have been compared with the results of quantum chemical calculations carried out in SSO MO LCAO approximation by the CNO, CNDO/2, and MPNDO/3 methods. In DMSO and THF solution the test compounds exist predominantly as 2-aryl-4-hydroxy-6H-1,3-oxazin-6-ones. The para substituent in the benzene ring does not affect the composition of the tautomer mixture significantly.For Communication 61, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 386–394, March, 1987. 相似文献
36.
K. L. Makovetskii V. A. Yakovlev T. G. Golenko G. N. Bondarenko 《Polymer Science Series B》2006,48(2):61-65
It was shown that branches can be incorporated into linear chains of cis-1,4-polybutadiene produced in the presence of neodymium catalysts. Branched polymers were prepared through the copolymerization of butadiene and a low-molecular-mass polybutadiene macromonomer containing a system of conjugated C=C bonds at chain ends. The incorporation of macromonomer units into the polymer chain was confirmed by the IR spectroscopic analysis of macromonomer-perdeuterobutadiene copolymers. 相似文献
37.
A. G. Kozlovskii K. A. Koshcheenko M. U. Arinbasarov T. G. Baklashova V. M. Adanin G. I. Yakovlev 《Russian Chemical Bulletin》1975,24(5):1061-1063
Conclusions The isolation of an unknown intermediary in the microbiological transformation of indole-3-acetic acid to 4-hydroxyindole-3-acetic acid may help us to determine the structure of 4-hydroxyindole-3-acetic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1155–1158, May, 1975.The authors express their gratitude to G. K. Skryabin and M. N. Kolosov for assistance in carrying out the present work. 相似文献
38.
It is proved that if M is a profinitely generated -module which is free as a module over the ring of p-adic integers, then M is determined up to free direct factors by its homology. This result generalizes the theorem on homological determinacy of p-adic representations of a cyclic group [Ref. Zh. Mat., 3A, 318 (1971)].Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeieniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 64, pp. 104–126, 1976. 相似文献
39.
40.
G. A. Sosnin O. O. Mironenko P. M. Eletskii R. G. Kukushkin Yu. K. Gulyaeva O. A. Bulavchenko E. Yu. Gerasimov A. A. Saraev V. V. Kaichev E. V. Khramov V. A. Yakovlev 《Journal of Structural Chemistry》2018,59(6):1308-1316
XRD, TEM, EXAFS/XANES methods are first used to study the structure and morphology of Mocontaining phases of carbon residues of heavy oil refining during catalytic steam cracking, catalytic cracking without water, and hydrocracking. According to the results obtained from physical and chemical studies of Mo-based catalytic phases, the reaction medium affects structural features of Mo-containing phases, e.g. the amount of oxide and sulphide forms, the particle size, and particle morphology. 相似文献