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1.
We study a fourth-order differential operator with matrix coefficients whose domain is determined by the Dirichlet boundary conditions. An asymptotics of the weighted average of the eigenvalues of this operator is obtained in the general case. As a consequence of this result, we present the asymptotics of the eigenvalues in several special cases. The obtained results significantly improve the already known asymptotic formulas for the eigenvalues of a one-dimensional fourth-order differential operator. 相似文献
2.
Polyakov K. M. Mordkovich N. N. Safonova T. N. Antipov A. N. Okorokova N. A. Dorovatovskii P. V. Veiko V. P. 《Crystallography Reports》2021,66(5):786-790
Crystallography Reports - Crystals of mutants of uridine phosphorylase from Shewanella oneidensis MR-1 at the active-site threonine residue were obtained, and the three-dimensional structures of... 相似文献
3.
Mathematical Notes - 相似文献
4.
I. V. Polyakov A. A. Moskovskii M. G. Khrenova A. V. Nemukhin 《Moscow University Chemistry Bulletin》2013,68(2):77-79
Ab initio approaches of quantum chemistry, including the fragment molecular orbital (FMO) method, as well as the multiconfigurational quasidegenerate perturbation theory (XMCQDPT2) and time-dependent density functional theory (TD DFT) were applied to compute optical spectra of a polyene dye molecule on the surface of titanium dioxide. 相似文献
5.
R. S. Borisov A. I. Polyakov L. A. Medvedeva N. I. Guranova L. G. Voskressensky 《Russian Chemical Bulletin》2012,61(8):1609-1615
Tetrazolo[1,5-a][1,4]benzodiazepines were obtained by an efficient azide five-centered four-component Ugi reaction, which used ketones, sodium azide, ammonium chloride, and the corresponding isonitrile. Scope and limitations of this multi-component reaction were considered. 相似文献
6.
K.?P.?PolyakovEmail author V.?V.?Polyakov V.?A.?Seredkin G.?S.?Patrin 《Bulletin of the Russian Academy of Sciences: Physics》2015,79(6):752-754
The results from investigating the magnetic and magneto-optical properties of Fe–Ti–O composite films with compositions above the percolation threshold, prepared via a solid-phase reaction with oxygen exchange in layered FeO/Ti structures, are presented. Features of the magneto-optical spectra of prepared films are compared to the spectra of continuous metal films. 相似文献
7.
A. N. Polyakov M. Noltemeyer T. Hempel J. Christen M. A. Stepovich 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(9):970-973
The use of time-of-flight cathodoluminescence measurements in the studies of semiconductor samples partially covered with a light-absorbing mask of special geometry in order to obtain new quantitative information about the properties of materials is shown. The values of the exciton diffusion coefficient are determined from the results obtained in an experimental study of gallium nitride. 相似文献
8.
9.
We discover that some unstable vacua have long memory. By that we mean that even in the theories containing only massive particles, there are correllators and expectation values which grow with time. We examine the cases of instabilities caused by the constant electric fields, expanding and contracting universes and, most importantly, the global de Sitter space. In the last case the interaction leads to a remarkable UV/IR mixing and to a large back reaction. This gives reasons to believe that the cosmological constant problem could be resolved by the infrared physics. 相似文献
10.
T. N. Gerasimenko V. I. Ivanov P. A. Polyakov Yu. V. Popov 《Journal of Mathematical Sciences》2011,172(6):761-769
Using the conformal-mapping technique, we have found analytical solutions of the current-distribution problem for different configurations of plain conductors. 相似文献