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1.
I. V. Denisova O. A. Ladyzhenskaya G. A. Seregin N. N. Uraltseva E. V. Frolova 《Journal of Mathematical Sciences》2005,130(4):4775-4779
Bibliography: 42 titles.__________Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 306, 2003, pp. 7–15. 相似文献
2.
3.
We prove estimates in weighted Hölder norms for a solution to the model linear problem related with the one-phase Stefan problem with a small multiplier ε at time derivative in the heat equation. These estimates are uniform with respect to parameter ε and are significant in justification of passage to the limit in the one-phase Stefan problem as the specific heat tends to zero. Bibliography: 8 titles. 相似文献
4.
A. A. Bredikhin V. A. Kirillovich L. V. Frolova A. N. Vereshchagin 《Russian Chemical Bulletin》1989,38(12):2476-2479
The ellipsoid of polarizability of the chloroformate fragment ClC(O)O has principle semiaxes b1=3.64, b2=5.34, b3=3.81 Å3; the angle between b1 and the C=0 bond is 24.5°. Aromatic chloroformates in solutions exist in conformations with cisoid position of the C=O and O-R bonds and the phenoxyl fragment in aromatic chloroformates deviates from the plane of the molecule.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2704–2708, December, 1989.The authors wish to thank S. G. Vul'fson for assistance in measuring the depolarization of Rayleigh light scattering. 相似文献
5.
E. N. Adamenko L. L. Frolova M. V. Panteleeva A. V. Kuchin 《Chemistry of Natural Compounds》2007,43(1):59-62
Optically active camphordihydro-2,3-pyrazine and camphorquinoxaline were prepared from camphoroquinone enantiomers. It was
shown that (1S,4R)-(+)-camphoroquinone was formed by oxidation of (1S,3R, 4R)-(−)-3-bromocamphor and (1R,4S)-(−)-camphoroquinone from (1R,3S, 4S)-(+)-3-bromocamphor, respectively. Camphor anhydride was a side product (6–10%) of the reaction.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–52, January–February, 2007. 相似文献
6.
O. S. Kukovinets T. I. Zvereva V. G. Kasradze F. Z. Galin L. L. Frolova A. V. Kuchin L. V. Spirikhin M. I. Abdullin 《Chemistry of Natural Compounds》2006,42(2):216-218
An effective method was proposed for synthesizing (+)-cis-1R-acetoxymethyl-3-isopropenyl-2,2-dimethylcyclobutane, a pheromone of the citrus mealybug, based on ozonolysis of verbenone
that led in one step to the key synthon 1R,3S-3-acetyl-2,2-dimethylcyclobutanecarboxylic acid.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 179–180, March–April, 2006. 相似文献
7.
Elena V. Frolova M. Ivanovskaya V. Sadykov G. Alikina A. Lukashevich S. Neophytides 《Progress in Solid State Chemistry》2005,33(2-4):317-325
Structural peculiarities of Ce–Zr–La–O and Ce–Zr–La–O/Ru samples in mean of catalytic properties are compared. The samples (Ce:Zr = 1:1, La = 10÷30 mol.%, Ru = 1.5 wt.%) were obtained by sol–gel method (X-samples) and co-precipitation (P-samples). It is shown that Ce0.45Zr0.45La0.1O2−δ/Ru X-samples are characterized by high thermal stability and the highest catalytic activity in partial methane oxidation reaction. According to XRD, BET, FTIR, EPR and XPS data it is concluded that the difference in the samples catalytic activity is caused by various disposition of Ru-containing phase on the support surface. The distinction in the dimension of Ru-containing particles (3D or 2D) is conditioned by structural peculiarities of Ce0.45Zr0.45La0.1O2−δ and Ce0.35Zr0.35La0.3O2−δ P- and X-samples. 相似文献
8.
The explicit solution of the equation u=f in a plane infinite angle, satisfying on one side of the angle a Neumann condition and on the other one the condition u/n + hu/r + u= (/r is the tangential derivative, C, 0), is constructed and estimated in weighted Sobolev spaces. The obtained estimates are sharp with respect to the differential order and are uniform with respect to . The construction of the solution reduces to the investigation of a finite difference equation in the complex plane, arising after a Mellin transform.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 182, pp. 149–167, 1990. 相似文献
9.
An efficient synthesis of 6-alkyl-3-cyano-2(1H)-pyridinethiones by the reactions of the sodium salts of -ketoaldehydes with cyanothioacetamide was developed. Pyridinethiones undergo selectiveS-alkylation with haloacetonitriles and haloacetophenones followed by cyclization to the corresponding thieno[2,3-b]pyridines.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 727–731, April, 1995.This study was financially supported by the Russian Foundation for Basic Research (Project No. 94-03-08-823). 相似文献
10.
5-Substituted 3-cyano-4,6-dimethylpyridine-2(lH)-thiones were synthesized by the re action of a-substituted -diketones with cyanothioacetamide in the presence of triethyl amine. The compounds synthesized were converted into thieno[2,3-blpyridines by treatment with organic halides and KOH.Translated fromlzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2719–2721, November, 1996. 相似文献