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951.
V. B. Sokolov A. N. Chekhlov T. A. Epishina I. V. Martynov 《Russian Chemical Bulletin》1992,41(2):236-240
The O-(arylcarbamoyl)butyrhydroximoyl chlorides were synthesized, and the x-ray structural analysis (XSA) of one of them — O-(o-tolylcarbamoyl)butyrhydroximoyl chloride — was performed. It was established from the data of the XSA and the PMR spectra that all synthesized compounds are the Z isomers.Institute of Physiologically Active Substances, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 315–319, February, 1992. 相似文献
952.
Alexandre N. Carvalho German Lozada-Cruz 《Journal of Mathematical Analysis and Applications》2007,325(2):1216-1239
We obtain existence of asymptotically stable nonconstant equilibrium solutions for semilinear parabolic equations with nonlinear boundary conditions on small domains connected by thin channels. We prove the convergence of eigenvalues and eigenfunctions of the Laplace operator in such domains. This information is used to show that the asymptotic dynamics of the heat equation in this domain is equivalent to the asymptotic dynamics of a system of two ordinary differential equations diffusively (weakly) coupled. The main tools employed are the invariant manifold theory and a uniform trace theorem. 相似文献
953.
954.
955.
A. F. Semenchev V. G. Gavrilyachenko E. M. Kuznetsova E. N. Sklyarova 《Physics of the Solid State》2006,48(6):1146-1148
The details of the mechanical effects (twinning and microcracking) are clarified at various stages of dynamic fatigue of PbTiO3 crystals using a polarization microscope and selective etching. 相似文献
956.
S. N. Vdovichev B. A. Gribkov S. A. Gusev V. L. Mironov D. S. Nikitushkin A. A. Fraerman V. B. Shevtsov 《Physics of the Solid State》2006,48(10):1902-1905
The statistics of left-and right-handed vortical magnetization states in a system of submicron-sized ferromagnetic disks is studied experimentally. Lattices of elliptic cobalt particles with a planar size of 750 × 450 nm and a thickness of 25 nm were formed using high-resolution electronic lithography. To visualize the magnetization distributions in the disks, magnetic force microscopy was used. The experimental results indicate the conservation of magnetic chiral symmetry in cobalt ferromagnetic particles of the above size and shape. 相似文献
957.
V. N. Esenin A. A. Stepanov L. I. Denisovich 《Russian Journal of Applied Chemistry》2006,79(12):1957-1963
Electrochemical procedure for express evaluation of the corrosion effect of aqueous glycol solutions on the metallic construction materials for cooling systems was studied. This procedure was used to develop new coolant formulations. 相似文献
958.
Treatment of aliphatic and aromatic aldehydes with chiral amines and trimethylsilyl cyanide in the absence or in the presence
of Lewis acids (including lithium perchlorate) under solvent-free conditions afforded the corresponding α-aminonitriles in
good yields and with a diastereoselectivity of 68 to 86%.
Published in Russian in Zhurnal Organicheskoi Khimii, 2006, Vol. 42, No. 1, pp. 56–59.
The text was submitted by the authors in English. 相似文献
959.
Role of readily hydrolyzable polysaccharides of larch wood in production of board materials is studied. 相似文献
960.
A generalized inverse problem for the identification of the absorption coefficient for a hyperbolic system is considered. The well-posedness of the problem is examined. It is proved that the regular part of the solution is an L 2 function, which reduces the inverse problem to minimizing the error functional. The gradient of the functional is determined in explicit form from the adjoint problem, and approximate formulas for its calculation are derived. A regularization algorithm for the solution of the inverse problem is considered. Numerical results obtained for various excitation sources are displayed. 相似文献