全文获取类型
收费全文 | 379篇 |
免费 | 15篇 |
国内免费 | 47篇 |
专业分类
化学 | 4篇 |
综合类 | 6篇 |
数学 | 424篇 |
物理学 | 7篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2020年 | 9篇 |
2019年 | 11篇 |
2018年 | 11篇 |
2017年 | 20篇 |
2016年 | 7篇 |
2015年 | 5篇 |
2014年 | 13篇 |
2013年 | 97篇 |
2012年 | 5篇 |
2011年 | 16篇 |
2010年 | 11篇 |
2009年 | 33篇 |
2008年 | 17篇 |
2007年 | 19篇 |
2006年 | 16篇 |
2005年 | 23篇 |
2004年 | 15篇 |
2003年 | 16篇 |
2002年 | 9篇 |
2001年 | 16篇 |
2000年 | 11篇 |
1999年 | 10篇 |
1998年 | 7篇 |
1997年 | 14篇 |
1996年 | 6篇 |
1995年 | 3篇 |
1994年 | 2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441条查询结果,搜索用时 15 毫秒
81.
Brent Kerby 《代数通讯》2013,41(12):5087-5103
In 1993, Muzychuk [23] showed that the rational Schur rings over a cyclic group Z n are in one-to-one correspondence with sublattices of the divisor lattice of n, or equivalently, with sublattices of the lattice of subgroups of Z n . This can easily be extended to show that for any finite group G, sublattices of the lattice of characteristic subgroups of G give rise to rational Schur rings over G in a natural way. Our main result is that any finite group may be represented as the (algebraic) automorphism group of such a rational Schur ring over an abelian p-group, for any odd prime p. In contrast, over a cyclic group the automorphism group of any Schur ring is abelian. We also prove a converse to the well-known result of Muzychuk [24] that two Schur rings over a cyclic group are isomorphic if and only if they coincide; namely, we show that over a group which is not cyclic, there always exist distinct isomorphic Schur rings. 相似文献
82.
Maria V. Milentyeva 《代数通讯》2013,41(4):1141-1154
We obtain the functions that bound the dimensions of finite dimensional nilpotent associative or Lie algebras of class 2 over an algebraically closed field in terms of the dimensions of their commutative subalgebras. As a result, we also compute a similar function for complex nilpotent Lie groups of class 2. 相似文献
83.
Peter V. Danchev 《代数通讯》2013,41(4):1461-1463
We show that in the article of Cutler and Missel (1984) there is, in fact, an example of an essentially finitely indecomposable (e.f.i.) abelian p-group which is not thick, and which can be chosen even to be separable, thus answering once again in the negative Irwin's conjecture that the e.f.i. p-groups are precisely the thick ones and that was already resolved in Dugas and Irwin (1992). 相似文献
84.
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
85.
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
86.
87.
88.
假设$\tau$是一个子群算子, $H$是有限群$G$的一个$p$-子群. 令 $\bar{G}=G/H_{G}$且$\bar{H}=H/H_{G}$, 如果$\bar{G}$有一个次正规子群$\bar{T}$ 和一个包含于$\bar{H}$ 的$\tau$-子群$\bar{S}$满足$\bar{G}=\bar{H}\bar{T}$且$\bar{H}\cap\bar{T}\leq \bar{S}\Phi(\bar{H})$, 就称$H$是$G$的一个$\Phi$-$\tau$- 可补子群. 文章通过讨论群$G$的准素数子群的$\Phi$-$\tau$-可补性给出了超循环嵌入和$p$-幂零性的一些新的特征. 相似文献
89.
极大子群的性质对有限群结构的影响 总被引:1,自引:0,他引:1
设H为有限群G的一个子群。称H在G中是s-半正规的,若对任意的素数p||G|,只要(p,|H|)=1,就有PH=HP,其中P∈Sylp(G);称H在G中是c-可补的,若存在G的子群N,使得G=HN且H∩N≤HG=CoreG(H)。证明了下面定理设F是一个包含超可解群类U的饱和群系,H△G,且G/H∈F。则G∈F,若下列条件之一成 相似文献
90.