全文获取类型
收费全文 | 2706篇 |
免费 | 167篇 |
国内免费 | 255篇 |
专业分类
化学 | 109篇 |
晶体学 | 2篇 |
力学 | 270篇 |
综合类 | 62篇 |
数学 | 2261篇 |
物理学 | 424篇 |
出版年
2024年 | 3篇 |
2023年 | 17篇 |
2022年 | 28篇 |
2021年 | 48篇 |
2020年 | 59篇 |
2019年 | 57篇 |
2018年 | 59篇 |
2017年 | 72篇 |
2016年 | 59篇 |
2015年 | 62篇 |
2014年 | 103篇 |
2013年 | 204篇 |
2012年 | 71篇 |
2011年 | 99篇 |
2010年 | 104篇 |
2009年 | 140篇 |
2008年 | 190篇 |
2007年 | 193篇 |
2006年 | 169篇 |
2005年 | 193篇 |
2004年 | 131篇 |
2003年 | 147篇 |
2002年 | 140篇 |
2001年 | 104篇 |
2000年 | 102篇 |
1999年 | 91篇 |
1998年 | 97篇 |
1997年 | 72篇 |
1996年 | 46篇 |
1995年 | 46篇 |
1994年 | 32篇 |
1993年 | 26篇 |
1992年 | 24篇 |
1991年 | 20篇 |
1990年 | 14篇 |
1989年 | 19篇 |
1988年 | 7篇 |
1987年 | 11篇 |
1986年 | 6篇 |
1985年 | 13篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 10篇 |
1981年 | 9篇 |
1980年 | 10篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有3128条查询结果,搜索用时 250 毫秒
141.
K. Varadarajan 《Proceedings Mathematical Sciences》2000,110(2):133-136
Define a ringA to be RRF (respectively LRF) if every right (respectively left)A-module is residually finite. We determine the necessary and sufficient conditions for a formal triangular matrix ring
to be RRF (respectively LRF). Using this we give examples of RRF rings which are not LRF. 相似文献
142.
时滞惯性流形及近似时滞惯性流形族 总被引:7,自引:0,他引:7
时滞惯性流形是对耗散系统惯性流形、近似惯性流形的最新发展,它基于对 大小涡分量间相互作用更细致的观察,即改变了惯性流形和近似惯性流形方法中大小 涡分量间相互作用为瞬时行为的隐含假定,而认为这种作用与系统的历史相关的.本 文结出了一类耗散系统时滞惯性流形的存在性证明,由于其存在性不需要“谱间隔条 件”保证,因而时滞惯性流形是广泛存在的.随后我们引出了一类离散的时滞惯性流 形,并在此基础上构造了一种近似时滞惯性流形族,分别给出了它们近似时滞惯性流 形的误差估计,结果显示这种新方法为构造稳定和高精度的算法提供了可能. 相似文献
143.
Large volume growth and finite topological type 总被引:5,自引:0,他引:5
D. Ordway B. Stephens D. G. Yang 《Proceedings of the American Mathematical Society》2000,128(4):1191-1196
It is shown in this paper that a complete noncompact -dimensional Riemannian manifold with nonnegative Ricci curvature, sectional curvature bounded from below, and large volume growth is of finite topological type provided that the volume growth rate of the complement of the cone of rays from a fixed base point is less than .
144.
通过对有限紧致空间中辐射场的研究来讨论腔中的原子-辐射场耦合系统. 利用T(1)×SO(4)群的表示, 给出了辐射场的单粒子波函数以及相应的色散关系. 由此详细讨论了紧致空间中辐射场的玻色-爱因斯坦统计. 发现其性质与空间的几何性质(曲率半径)有显著的依赖关系, 并表现与通常黑体辐射系统的显著差异. 相似文献
145.
The one-dimensional totally asymmetric simple exclusion process (TASEP) is considered. We study the time evolution property
of a tagged particle in the TASEP with the step initial condition. Calculated is the multi-time joint distribution function
of its position. Using the relation of the dynamics of the TASEP to the Schur process, we show that the function is represented
as the Fredholm determinant. We also study the scaling limit. The universality of the largest eigenvalue in the random matrix
theory is realized in the limit. When the hopping rates of all particles are the same, it is found that the joint distribution
function converges to that of the Airy process after the time at which the particle begins to move. On the other hand, when
there are several particles with small hopping rate in front of a tagged particle, the limiting process changes at a certain
time from the Airy process to the process of the largest eigenvalue in the Hermitian multi-matrix model with external sources. 相似文献
146.
Tiexiang Li 《Journal of Mathematical Analysis and Applications》2010,369(1):245-257
In this paper, we study the decomposition of the Nehari manifold via the combination of concave and convex nonlinearities. Furthermore, we use this result and the Ljusternik-Schnirelmann category to prove that the existence of multiple positive solutions for a Dirichlet problem involving critical Sobolev exponent. 相似文献
147.
V. P. Burichenko 《Algebra and Logic》2008,47(6):384-394
Let G = SL(n, q), where q is odd, V be a natural module over G, and L = S2(V) be its symmetric square. We construct a 2-cohomology group H2(G, L). The group is one-dimensional over F
q if n = 2 and q ≠ 3, and also if (n, q) = (4, 3). In all other cases H2(G, L) = 0. Previously, such groups H2(G, L) were known for the cases where n = 2 or q = p is prime. We state that H2(G, L) are trivial for n ⩾ 3 and q = pm, m ⩾ 2. In proofs, use is made of rather elementary (noncohomological) methods.
__________
Translated from Algebra i Logika, Vol. 47, No. 6, pp. 687–704, November–December, 2008. 相似文献
148.
Spectra of finite linear and unitary groups 总被引:1,自引:0,他引:1
A. A. Buturlakin 《Algebra and Logic》2008,47(2):91-99
The spectrum of a finite group is the set of its element orders. An arithmetic criterion determining whether a given natural
number belongs to a spectrum of a given group is furnished for all finite special, projective general, and projective special
linear and unitary groups.
Supported by RFBR (grant Nos. 08-01-00322 and 06-01-39001) and by the Council for Grants (under RF President) and State Aid
of Leading Scientific Schools (project NSh-344.2008.1).
__________
Translated from Algebra i Logika, Vol. 47, No. 2, pp. 157–173, March–April, 2008. 相似文献
149.
This article generalizes the formulas of Gauss-Ostrogradskii type for semibasic vector fields from Riemannian manifolds to real Finsler manifolds and obtains some formulas of Gauss-Ostrogradskii type for Finsler vector fields which are expressed in terms of the vertical and horizontal derivatives of the Cartan connection in real Finsler manifolds. 相似文献