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341.
I. V. Tatarinova L. V. Morozova M. V. Markova A. M. Vasil’tsov A. V. Ivanov G. F. Myachina S. S. Khutsishvili A. I. Mikhaleva B. A. Trofimov 《Polymer Science Series B》2011,53(3-4):125-131
Polyfunctional reactive copolymers of N-vinylpyrrole-2-carbaldehydes with styrene, N-vinylpyrrolidone, and ethylene glycol vinyl glycidyl ether are synthesized in the presence of AIBN (2 wt %, 80°C, 50 h) with a yield of up to 98% and a molecular mass of up to 4800. The copolymers show paramagnetic behavior (N = 2.0 × 1015?2.0 × 1017 g?1) and possess the properties of organic semiconductors (σ = 0.9 × 10?11–2.8 × 10?7 S/cm after doping with I2). 相似文献
342.
B. A. Trofimov M. V. Markova L. V. Morozova A. I. Mikhaleva E. Yu. Shmidt N. V. Zorina Sang Heon Hyun 《Polymer Science Series B》2010,52(3-4):193-197
Polymers of 1,4-bis[2-(N-vinyl)pyrrolyl]benzene with free N-vinyl groups in side chains are synthesized in the presence of AIBN (2–5 wt %, 70°C) with a yield of up to 34% and a molecular mass of up to 11.5 × 103. In the presence of cationic catalysts (Me3SiCl, the LiBF4-dimethoxyethane system, and BF3 · OEt2), 1,4-bis[2-(N-vinyl)pyrrolyl]benzene gives macromolecules with alternating 1,2-pyrrolene and ethylidene units in the backbone with yields of 80, 44, and 33%, respectively. The polymers demonstrate paramagnetic and luminescent properties. 相似文献
343.
Lyubov' N. Sobenina Vladislav N. Drichkov Al'bina I. Mikhaleva Olga V. Petrova Igor A. Ushakov Boris A. Trofimov 《Tetrahedron》2005,61(20):4841-4849
5-Amino-3-(pyrrol-2-yl)isoxazoles were selectively prepared by the reaction of 2-(2,2-dicyano-1-ethylthioethenyl)pyrroles with hydroxylamine in methanol. Under analogous conditions, 2-(2-carbamoyl-2-cyano-1-ethylthioethenyl) pyrroles with hydroxylamine gave 5-aminoisoxazoles and their structural isomers, 3-aminoisoxazoles (3-5% yield). The latter were selectively prepared by reacting 2-(2-carbamoyl-2-cyano-1-ethylthioethenyl)pyrroles with hydroxylamine in the presence of aqueous NaOH and from the products of intramolecular cyclization of 2-(2-carbamoyl-2-cyano-1-ethylthioethenyl)pyrroles, 1-ethylthio-3-iminopyrrolizines and hydroxylamine. 相似文献
344.
Boris A. Trofimov Prof. Elena Yu. Schmidt Dr. Igor' A. Ushakov Dr. Nadezhda V. Zorina Dr. Elena V. Skital'tseva Nadezhda I. Protsuk Dr. Al'bina I. Mikhaleva Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(28):8516-8521
Alkylaryl‐ and alkylheteroarylketones, including those with condensed aromatic moieties, are readily vinylated with arylacetylenes (KOH/DMSO, 100 °C, 1 h) to give regio‐ and stereoselectively the (E)‐β‐γ‐ethylenic ketones ((E)‐3‐buten‐1‐ones) in 61–84 % yields and with approximately 100 % stereoselectivity. This vinylation represents a new C(sp3)? C(sp2) bond‐forming reaction of high synthetic potential. 相似文献
345.
K. Yu. Bogachev M. Yu. Mikhaleva I. G. Gorelov 《Moscow University Mathematics Bulletin》2010,65(4):156-160
The algebraic multilevel method AMG is compared with the method BICGSTAB+ILU on a model problem with a strong anisotropy. The method AMG was used as a part of the method CPR for solution of the filtration problems of a viscous compressible fluid flow in porous media. The algorithm CPR+AMG is compared with CPR+ILU on the base of this problem. The work of the CPR+AMG is analyzed by solving the problem for a model oil field. 相似文献
346.
S. V. Stovbun S. N. Nikol’skii V. P. Mel’nikov M. G. Mikhaleva Ya. A. Litvin A. N. Shchegolikhin D. V. Zlenko V. A. Tverdislov D. S. Gerasimov A. D. Rogozin 《Russian Journal of Physical Chemistry B, Focus on Physics》2016,10(2):245-259
The physical mechanisms responsible for the kinetics of nitration of cellulose raw materials of different origin have been studied. It has been shown that the main nitration rate-limiting factor is the speed of untwisting of supercoiled cellulose fibers. This process limits the penetration of nitrating agents into microcrystalline regions and, thus, the total reaction rate. The constructed physical model provides an adequate explanation of all the experimentally observed features of the cellulose nitration process, particularly as a function of cellulose origin (cotton, flax, wood) and preparation/treatment methods (sulfite, sulfate, bleached, refined with sulfurous or boric acids or acetone). The theoretical results have been tested in practice. 相似文献
347.
348.