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991.
CH2?CHCH2CpTiCl3 (1), CH2?CHCH2CH2CpTiCl3 (2) and CH3CH2CH3CpTiCl3 (3) have been synthesized and characterized. The influence of the alkenyl substituent groups on the catalyst activities in the syndiotactic polymerization of styrene was investigated. The catalyst activities decreased in the order CH2?CHCH2CH2CpTiCl3 > CH3CH2CH2CH2CpTiCl3 > CH3CH2CH2CpTiCl3 > CH2?CHCH2CpTiCl3 (Cp?C5H4). By using complex 1, the dependence of the activity on the concentration of methylaluminoxane, triisobutylaluminum and diisobutylaluminum hydride was investigated. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
992.
We follow the group representation theory approach to define causal operators on Banach modules and present some of their spectral properties. 相似文献
993.
We prove the existence of infinite subgroups with nontrivial locally finite radicals and of locally finite subgroups in the groups with almost finite almost solvable elements of prime orders and in the groups with generally finite elements. 相似文献
994.
We study combinatorial properties of the alternating subgroup of a Coxeter group, using a presentation of it due to Bourbaki. 相似文献
995.
For a compact connected group G, in a compact free G-space M every closed subset is the fixed point set of an autohomeomorphism if the weight of M is not bigger than that of G. In a compact group with nonsingleton components, every closed subset is the fixed point set of an autohomeomorphism if and only if the weight of the whole group is not bigger than that of the component of the identity. 相似文献
996.
R. I. Grigorchuk 《Mathematical Notes》1996,60(3):274-282
The paper is devoted to the study of weights on groups. A connection between weight functions and harmonic functions is established.
A relationship between the weight theory on groups with the “Tychonoff property” and the theory of bounded cohomology is presented.
It is proved that the Beurling algebraℓ1 (G, ω) constructed for the weightω is amenable if and only if the groupG is amenable and the weightω is equivalent to a multiplicative characterχ:G→ℝ+.
Translated fromMatematicheskie Zametki, Vol. 60, No. 3, pp. 448–460, September, 1996.
This research was partially supported by the Russian Foundation for Basic Research under grant No. 96-01-00974 and by the
INTAS Foundation under grant No. 94-3420. 相似文献
997.
一类量子环面李代数的自同构群 总被引:3,自引:0,他引:3
=C_q[x_1~(±1),x_2~(±1)]为复数域上的非交换环面结合代数,A=\C,Der为的导子李代数.本文研究李代数L_q=DerA的自同构群Aut L_q. 相似文献
998.
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
999.
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
1000.
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