全文获取类型
收费全文 | 299篇 |
免费 | 8篇 |
国内免费 | 39篇 |
专业分类
化学 | 4篇 |
综合类 | 6篇 |
数学 | 328篇 |
物理学 | 8篇 |
出版年
2023年 | 2篇 |
2022年 | 5篇 |
2020年 | 8篇 |
2019年 | 9篇 |
2018年 | 8篇 |
2017年 | 17篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 11篇 |
2013年 | 81篇 |
2012年 | 4篇 |
2011年 | 15篇 |
2010年 | 9篇 |
2009年 | 26篇 |
2008年 | 15篇 |
2007年 | 10篇 |
2006年 | 10篇 |
2005年 | 18篇 |
2004年 | 12篇 |
2003年 | 13篇 |
2002年 | 7篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 6篇 |
1998年 | 6篇 |
1997年 | 10篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1959年 | 2篇 |
排序方式: 共有346条查询结果,搜索用时 15 毫秒
41.
42.
It is proved that in many cases of interest the actions of groups on rooted trees can be recovered from the structure of the groups. The results apply to most of the groups introduced by the first author and to the Gupta–Sidki groups; they are proved in the wider context of branch groups satisfying two natural conditions. 相似文献
43.
Let be a field of positive characteristic and the group algebra of a group . It is known that, if is Lie nilpotent, then its upper (and lower) Lie nilpotency index is at most , where is the order of the commutator subgroup. The authors previously determined those groups for which this index is maximal and here they determine the groups for which it is `almost maximal', that is, it takes the next highest possible value, namely .Presented by V. Dl a b.Dedicated to Professor Vjacheslav Rudko on his 65th birthday.The research was supported by OTKA No. T 037202, No. T 038059 and Italian National Research Project “Group Theory and Application.” 相似文献
44.
45.
The structure of finite non-nilpotent groups in which every 2-maximal subgroup permutes with every 3-maximal subgroup is described. 相似文献
46.
Following Rose, a subgroup H of a group G is called contranormal, if G = H G . In certain sense, contranormal subgroups are antipodes to subnormal subgroups. It is well known that a finite group is nilpotent if and only if it has no proper contranormal subgroups. However, for the infinite groups this criterion is not valid. There are examples of non-nilpotent infinite groups whose subgroups are subnormal; in paricular, these groups have no contranormal subgroups. Nevertheless, for some classes of infinite groups, the absence of contranormal subgroups implies the nilpotency of the group. The current article is devoted to the search of such classes. Some new criteria of nilpotency in certain classes of infinite groups have been established. 相似文献
47.
48.
In this article a class of subgroups of a finite group G, called Q-injectors, is introduced. If G is soluble, the Q-injectors are precisely the injectors of the Fitting sets. A characterization of nilpotent Q-injectors is given as well as a sufficient condition for the solubility of a finite group G, in terms of Q-injectors, which generalizes a well known result. 相似文献
49.
For a finite group G, let ψ(G) denote the sum of element orders of G. The aim of this article is to show that ψ(H) < ψ(A n ) for every proper subgroup H of the symmetric group of degree n, which is different from the alternating group A n . 相似文献
50.
Let W be a finite Coxeter group, P a parabolic subgroup of W, and N W (P) the normalizer of P in W. We prove that every element in N W (P) is strongly real in N W (P), and that every irreducible complex character of N W (P) has Frobenius-Schur indicator 1. 相似文献