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191.
We consider the inverse problem of source identification for the heat conduction problem. The neoclassical formulation of
the direct problem with integral boundary condition is used. Conditions for unique solvability of the inverse problem are
obtained.
__________
Translated from Prikladnaya Matematika i Informatika, No. 23, pp. 36–50, 2006. 相似文献
192.
We examine both theoretically and experimentally the possibility of miniaturization of planar microstrip dipole antennas of
small electric dimensions. The antennas are made from high-temperature superconductors. The dependence of the matching conditions
and the bandwidth on the design and geometrical features of the antennas is analyzed. It is shown that a superconductor antenna
of size L≅(0.05–0.1)λ can have about 100% efficiency and a bandwidth of 0.2–2%. We propose a miniature microstrip antenna
of dimensions 11 mm×11 mm for the frequency band 1.3 GHz. Measurements of the radio characteristics of the copper mockup of
the antenna confirmed the efficiency of the optimization.
Radiophysical Research Institute, Institute of Physics of Microstructures of the Russian Academy of Sciences, Nizhny Novgorod,
Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 42, No. 2, pp. 158–167, February 1999. 相似文献
193.
Semenov V. E. Mikhailov A. S. Romanova E. S. Voloshina A. D. Kulik N. V. Uraleva S. Yu. Kozlov A. V. Latypov Sh. K. Reznik V. S. 《Russian Journal of General Chemistry》2009,79(1):134-137
Russian Journal of General Chemistry - Reactions of pyrimidinophanes containing two 6-methylthiocytosine and one 6-methyluracil fragments with methyl p-toluenesulfonate gave amphiphilic macrocyclic... 相似文献
194.
V. A. Mamedov L. V. Mustakimova A. T. Gubaidullin S. V. Vdovina I. A. Litvinov V. S. Reznik 《Chemistry of Heterocyclic Compounds》2006,42(9):1229-1232
Acid-catalyzed cyclocondensation in a three component system of dichloromethylacetylbenzoylmethanes, urea, and aromatic aldehydes
occurred regio-and stereoselectively to give polyfunctional derivatives of perhydropyrimidine.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, 1414–1417, September, 2006. 相似文献
195.
A.I. Titov B. Kämpfer B.L. Reznik 《The European Physical Journal A - Hadrons and Nuclei》2000,7(4):543-557
We analyze the production of φ mesons in πN and NN reactions in the near-threshold region, using throughout the conventional “non-strange” dynamics based on such processes
which are allowed by the non-ideal ω-φ mixing. We show that the occurrence of the direct φNN interaction may show up in different unpolarized and polarization observables in πN→Nφ reactions. We find a strong non-trivial difference between observables in the reactions pp→ppφ and pn→pnφ caused by the different role of the spin singlet and triplet states in the entrance channel. A series of predictions for
the experimental study of this effect is presented.
Received: 27 January 2000 相似文献
196.
V. E. Semenov A. E. Nikolaev L. F. Galiullina O. A. Lodochnikova I. A. Litvinov A. P. Timosheva V. E. Kataev Yu. Ya. Efremov D. R. Sharafutdinova A. V. Chernova Sh. K. Latypov V. S. Reznik 《Russian Chemical Bulletin》2006,55(3):559-568
The reactions of 1,3-bis(5-bromopentyl)-5-methyl-or 1,3-bis(5-bromopentyl)-6-methyl-uracil with benzylamine afforded pyrimidinophanes
containing the nitrogen atom in the polymethylene bridge. Single-crystal X-ray diffraction study and NMR and UV spectroscopic
study in solution demonstrated that the phenyl and uracil fragments in the macrocycles are in spatial proximity. Unlike the
known macrocycles containing the pyrimidine ring, the pyrimidinophanes under study are conformationally rigid.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 539–547, March, 2006. 相似文献
197.
198.
Fattakhov S. G. Solov'eva S. E. Efremov Yu. Ya. Rizvanov I. Kh. Reznik V. S. 《Russian Journal of General Chemistry》2001,71(3):469-470
Mannich reaction of 1,3-bis[4-(2-mercaptomethylphenoxy)butyl]-6-methyl-1,2,3,4-tetrahydropyrimidine-2,4-dione, formaldehyde, and N-benzylamine afforded a 24-membered macrocyclic compound containing an uracil fragment, 1,3-(11-benzyl-6,7:15,16-dibenzo-5,17-dioxa-9,13-dithia-11-aza-6,15-heneicosadiene-1,21-diyl)-6-methyl-1,2,3,4-tetrahydropyrimidine-2,4-dione. 相似文献
199.
200.