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981.
Contiguous operators for a two-parameter analogue of hypergeometric series are constructed. These represent a two-parameter quantum enveloping algebra introduced by Takeuchi. 相似文献
982.
983.
Large sets of disjoint group‐divisible designs with block size three and type 2n41 were first studied by Schellenberg and Stinson because of their connection with perfect threshold schemes. It is known that such large sets can exist only for n ≡0 (mod 3) and do exist for all odd n ≡ (mod 3) and for even n=24m, where m odd ≥ 1. In this paper, we show that such large sets exist also for n=2k(3m), where m odd≥ 1 and k≥ 5. To accomplish this, we present two quadrupling constructions and two tripling constructions for a special large set called *LS(2n). © 2002 Wiley Periodicals, Inc. J Combin Designs 11: 24–35, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jcd.10032 相似文献
984.
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
985.
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
986.
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
987.
We study combinatorial properties of the alternating subgroup of a Coxeter group, using a presentation of it due to Bourbaki. 相似文献
988.
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
989.
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
990.
Hao ZHAO Wen Huai SHEN 《数学学报(英文版)》2007,23(12):2145-2154
In general category, the group of self-equivalences of sum object can decompose as the product of its two subgroups under certain conditions and also several split short exact sequences are obtained. Subsequently, we apply the above results to the category of space under a space and get some results which are dual to those in fibrewise category. 相似文献