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981.
Suguru Motokucho Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2007,45(19):4459-4464
A five‐membered cyclic dithiocarbonate having phenylcarbamate moiety 1 underwent cationic ring‐opening polymerization by using methyl trifluoromethanesulfonate as an initiator in nitrobenzene at 60 °C. Both of the corresponding first‐order kinetic plot and conversion‐molecular weight plot showed linearity to suggest the living fashion of the polymerization, which was then supported by two‐stage polymerization experiment. The living fashion as well as the regioselective formation of the repeating unit suggested significant contribution of the neighboring group participation of the carbamate group to form a stabilized cationic propagating end, of which structure was confirmed by performing an equimolar reaction of 1 and methyl trifluoromethanesulfonate with analyzing the resulting species by NMR spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4459–4464, 2007 相似文献
982.
设F是一个特征2且至少含有5个元素的域,n≥2是一个正整数.令Mn(F)和Tn(F)分别F上的全矩阵空间和上三角矩阵空间.我们首先刻划从Tn(F)到Mn(F)的保矩阵群逆的所有线性单射,由此从Tn(F)到自身的所有保矩阵群逆的线性双射被刻划. 相似文献
983.
E. I. Timoshenko 《Algebra and Logic》2006,45(4):254-260
It is proved that test rank of a free solvable non-Abelian group of finite rank is 1 less than the rank of that group. This
gives the answer to Question 14.88 posed in the Kourovka Notebook by Fine and Shpilrain, asking whether or not a free solvable
group of rank 2 and solvability index n ≥ 3 has test elements.
Supported by RFBR grant No. 05-01-00292.
__________
Translated from Algebra i Logika, Vol. 45, No. 4, pp. 447–457, July–August, 2006. 相似文献
984.
985.
We explore analogues of o‐minimality and weak o‐minimality for circularly ordered sets. Much of the theory goes through almost unchanged, since over a parameter the circular order yields a definable linear order. Working over ?? there are differences. Our main result is a structure theory (with infinitely many doubly transitive examples related to Jordan permutation groups) for ?0‐categorical weakly circularly minimal structures. There is a 5‐homogeneous (or ‘5‐indiscernible’) example which is not 6‐homogeneous, but any example which is k‐homogeneous for some k ≥ 6 is k‐homogeneous for all k. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
986.
We show that every unitary representation π of a connected Lie group G is characterized up to quasi-equivalence by its complete moment set.Moreover, irreducible unitary representations π of G are characterized by their moment sets. 相似文献
987.
988.
HUANG Xiaojun 《中国科学A辑(英文版)》2006,49(11):1441-1450
In this paper, we discuss some recent studies on the complex structure of an isolated normal singularity by using the information
from its link. We also give some open problems to be further pursued.
Dedicated to Professor Sheng GONG on the occasion of his 75th birthday 相似文献
989.
990.
A finite group G is said to be recognizable by spectrum, i.e., by the set of element orders, if every finite group H having the same spectrum as G is isomorphic to G. We prove that the simple linear groups L
n
(2k) are recognizable by spectrum for n = 2m ≥ 32.Original Russian Text Copyright © 2005 Vasil’ev A. V. and Grechkoseeva M. A.The authors were supported by the Russian Foundation for Basic Research (Grant 05-01-00797), the State Maintenance Program for the Leading Scientific Schools of the Russian Federation (Grant NSh-2069.2003.1), the Program “ Development of the Scientific Potential of Higher School” of the Ministry for Education of the Russian Federation (Grant 8294), the Program “Universities of Russia” (Grant UR.04.01.202), and a grant of the Presidium of the Siberian Branch of the Russian Academy of Sciences (No. 86-197).__________Translated from Sibirskii Matematicheskii Zhurnal, Vol. 46, No. 4, pp. 749–758, July–August, 2005. 相似文献