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981.
T. V. Gubaidulina N. I. Chistyakova V. S. Rusakov 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(9):1269-1272
Natural and synthetic layered iron hydroxysulfides: tochilinite and valleriite, have been investigated by Mössbauer spectroscopy. Tochilinite, magnetite, troilite, and pyrite phases were found in the products of tochilinite synthesis under different conditions. The relative contents of the phases found are determined as functions of the relative magnesium content in the initial mixture. Crystallochemical identification of the 57Fe subspectra of valleriite has been performed. 相似文献
982.
It is shown that several parameters of the near-field interaction of particles effectively control the reflectance of the interface between vacuum and a semi-infinite medium in a structured monolayer of nanoparticles, changing it from 0 to 1. The formulas derived for the electric field amplitudes inside and outside the nanostructural layer take into account the periodic arrangement of nanoparticles. The ideal blooming condition of the boundary of the underlying medium is derived, under which the reflectance of the interface tends to zero in a wide range of wavelengths in the visible optical range. 相似文献
983.
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
984.
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
985.
986.
987.
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
988.
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
989.
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
990.
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