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1.
The steady-state two-phase flow non-linear equation is considered in the case when one of phases has low effective permeability in some periodic set, while on the complementary set it is high; the second phase has no contrast of permeabilities in different zones. A homogenization procedure gives the homogenized model with macroscopic effective permeability of the second phase depending on the gradient and on the second order derivatives of the macroscopic pressure of the first phase. This effect cannot be obtained by classical (one small parameter) homogenization. To cite this article: G.P. Panasenko, G. Virnovsky, C. R. Mecanique 331 (2003). 相似文献
2.
We consider the problem of solving the integral form of the radiative transfer equation in an atmosphere with optical thickness τ0?1. We propose two methods transforming this problem to a finite set of the independent problems of the same type set in an atmosphere with optical thickness much less then τ0. The error estimates are derived. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
3.
O. M. Radul M. Z. Krimer O. N. Rebrova V. N. Biyushkin I. V. Feofanova A. A. Panasenko 《Russian Chemical Bulletin》1993,42(3):522-527
The rearrangement of enol acylates of aryl 1H-1, 2, 4-triazol-1-ylmethyl ketones at 140–150°C in acetic anhydride is studied. The migration of the acyl group to the C(5) atom of the heterocycle is found to be intramolecular. The characteristics of the original and final products are presented. X-ray structural studies of the enol acetates of 2, 4-dichlorophenyl 1H-1, 2, 4-triazol-1-ylmethyl ketone and 2, 4-dichlorophenyl 5-acetyl-1H-1, 2, 4-triazol-1-ylmethyl ketone are carried out.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 560–564, March, 1993. 相似文献
4.
A. A. Panasenko L. V. Spirikhin B. V. Flekhter G. A. Tolstikov 《Russian Chemical Bulletin》1984,33(11):2287-2290
Conclusions The1H and13C NMR spectra were studied for 2,3,4-trisubstituted sulfolanes and the isomerism of these compounds was determined, The use of chemical shift information is more convenient to determine the isomerism of polysubstituted cyclic compounds by PMR spectroscopy, while use of the direct carbon-proton coupling constants is more convenient for this problem when employing13C NMR spectroscopy.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2498–2501, November 1984. 相似文献
5.
L. M. Khalilov L. A. Baltina L. V. Spirikhin E. V. Vasil'eva R. M. Kondratenko A. A. Panasenko G. A. Tolstikov 《Chemistry of Natural Compounds》1990,25(4):426-430
Details of the13C NMR spectra of glycyrrhizic acid and four of its derivatives are given, and on their basis the configurations of the anomeric centers of the carbohydrate chain have been redetermined and the -configuration of the C-1 carbon atom has been suggested.Institute of Chemistry, Bashkir Scientific Center, Urals Branch, USSR Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 500–505, July–August, 1989. 相似文献
6.
L. M. Khalilov V. S. Sultanova E. V. Vasil'eva L. V. Spirikhin I. P. Baikova S. N. Lakeev F. Z. Galin G. A. Tolstikov A. A. Panasenko 《Chemistry of Natural Compounds》1989,24(4):491-497
The structures have been established and the stereochemical assignments have been made of eight pairs of diastereomers and three quartets of stereoisomers of esters of 2,2-dialkylspiro[cyclopropane-3,3-indene]-1-carboxylic acids of the pyrethroid series by the methods of13C NMR spectroscopy using the shift reagent Eu(fod)3. Criteria have been found for assigning the stereoisomers on the basis of the characteristic values of the13C NMR chemical shifts of the signals of the methyl groups at C-2 for determining configuration of the substituents of the cyclopropane moiety of the molecule and of the C-2 signal itself for identifying isomers with respect to the side chain of the pyrethroid molecule. Criteria are proposed for identifying stereoisomers from the chemical shifts of the protons of the gem-dimethyl groups at C-2 in the1H NMR spectra.Institute of Chemistry, Bashkir Branch, Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 577–583, July–August, 1988. 相似文献
7.
L. M. Khalilov O. V. Shitikova A. A. Gimaev R. I. Khusnutdinov U. M. Dzhemilev A. A. Panasenko G. A. Tolstikov 《Russian Chemical Bulletin》1990,39(9):1792-1796
13C NMR spectra have been obtained for six isomers of bicyclo[2.2.1]heptadiene (norbornadiene) trimers, and a complete stereochemical assignment of these isomers has been made by means of a computer-assisted calculation of chemical shifts.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1973–1978, September, 1990. 相似文献
8.
L. M. Khalilov O. V. Shitikova V. S. Sultanova V. A. Dokichev C. Z. Sultanov A. A. Panasenko U. M. Dzhemilev G. A. Tolstikov 《Russian Chemical Bulletin》1990,39(3):481-484
The13C NMR spectra of 15 spirocyclopropane derivatives in the (C7)-norbornane series have been investigated, signal assignments made, and the stereochemistry of isomeric products has been determined. It was found that the methylene group signals in the cyclopropane fragment may be used as criteria in making the stereochemical assignments.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 555–559, March, 1990. 相似文献
9.
L. M. Khalilov O. V. Shitikova R. I. Khusnutdinov Z. S. Muslimov U. M. Dzhemilev A. A. Panasenko G. A. Tolstikov 《Russian Chemical Bulletin》1990,39(3):484-488
The structures of the dimerization products of spiro(bicyclo[2.2.1]hepta-2,5-diene-7,1-cyclopropane) have been solved using13C NMR spectroscopy and their stereochemical assignments made. The methylene carbon atom signals for the spirocyclopropane fragment can be used as diagnostic signals in making the stereochemical assignments.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 559–564, March, 1990. 相似文献
10.
A. A. Panasenko A. F. Kaprosh M. A. Rekhter E. P. Styngach M. Z. Krimer G. N. Grushetskaya 《Russian Chemical Bulletin》1994,43(3):391-394
13C NMR spectra (20 and 75 MHz, in DMSO-d6) of a series of 1,3-diaryl-3-(1H-1,2,4-triazol-1-yl)- and 1,3-diaryl-2-(1H-1,2,4-triazol-1-yl)prop-2-en-1-ones were registered. It was shown that the chemical shifts of both the carbon atom of the alkene group and C(3) reflect regio- and stereoisomerism of these compounds. Taking this into account the isomeric structures of several 1,3-diaryl-3-(1H-1,2,4-triazol-1-yl)prop-2-en-1-ones were identified and the configurations relative to the double bond of a number of 1,3-diaryl-2-(1H-1,2,4-triazol-1-yl)prop-2-en-1-ones were determined. 相似文献