全文获取类型
收费全文 | 1874篇 |
免费 | 59篇 |
国内免费 | 17篇 |
专业分类
化学 | 1048篇 |
晶体学 | 14篇 |
力学 | 61篇 |
数学 | 522篇 |
物理学 | 305篇 |
出版年
2023年 | 11篇 |
2022年 | 86篇 |
2021年 | 83篇 |
2020年 | 62篇 |
2019年 | 56篇 |
2018年 | 68篇 |
2017年 | 40篇 |
2016年 | 84篇 |
2015年 | 76篇 |
2014年 | 78篇 |
2013年 | 135篇 |
2012年 | 125篇 |
2011年 | 145篇 |
2010年 | 96篇 |
2009年 | 82篇 |
2008年 | 103篇 |
2007年 | 80篇 |
2006年 | 93篇 |
2005年 | 73篇 |
2004年 | 66篇 |
2003年 | 38篇 |
2002年 | 54篇 |
2001年 | 20篇 |
2000年 | 25篇 |
1999年 | 16篇 |
1998年 | 15篇 |
1997年 | 16篇 |
1996年 | 14篇 |
1995年 | 10篇 |
1994年 | 12篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1991年 | 11篇 |
1990年 | 10篇 |
1989年 | 7篇 |
1988年 | 7篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有1950条查询结果,搜索用时 15 毫秒
1.
2.
Tomasz Przebinda 《Journal of Functional Analysis》2018,274(5):1284-1305
We relate the distribution characters and the wave front sets of unitary representation for real reductive dual pairs of type I in the stable range. 相似文献
3.
Based on computer simulations, Kauffman (Physica D, 10, 145-156, 1984) made several generalizations about a random Boolean cellular automaton which he invented as a model of cellular metabolism. Here we give the first rigorous proofs of two of Kauffman's generalizations: a large fraction of vertices stabilize quickly, consequently the length of cycles in the automaton's behavior is small compared to that of a random mapping with the same number of states; and reversal of the states of a large fraction of the vertices does not affect the cycle to which the automaton moves. 相似文献
4.
Tomasz Luczak 《Random Structures and Algorithms》1991,2(4):421-439
Let G(n, M) be a graph chosen at random from the family of all labelled graphs with n vertices and M(n) = 0.5n + s(n) edges, where s3(n)n?2→∞ but s(n) = o(n). We find the limit distribution of the length of shortest cycle contained in the largest component of G(n, M), as well as of the longest cycle outside it. We also describe the block structure of G(n, M) and derive from this result the limit probability that G(n, M) contains a cycle with a diagonal. Finally, we show that the probability tending to 1 as n-→∞ the length of the longest cycle in G(n, M) is of the order s2(n)/n. 相似文献
5.
6.
7.
Sharp upper and lower bounds are obtained for the reliability functions and the expectations of lifetimes of coherent systems based on dependent exchangeable absolutely continuous components with a given marginal distribution function, by use of the concept of Samaniego's signature. We first show that the distribution of any coherent system based on exchangeable components with absolutely continuous joint distribution is a convex combination of distributions of order statistics (equivalent to the k-out-of-n systems) with the weights identical with the values of the Samaniego signature of the system. This extends the Samaniego representation valid for the case of independent and identically distributed components. Combining the representation with optimal bounds on linear combinations of distribution functions of order statistics from dependent identically distributed samples, we derive the corresponding reliability and expectation bounds, dependent on the signature of the system and marginal distribution of dependent components. We also present the sequences of exchangeable absolutely continuous joint distributions of components which attain the bounds in limit. As an application, we obtain the reliability bounds for all the coherent systems with three and four exchangeable components, expressed in terms of the parent marginal reliability function and specify the respective expectation bounds for exchangeable exponential components, comparing them with the lifetime expectations of systems with independent and identically distributed exponential components. 相似文献
8.
Tomasz Stawski Janusz Szklarzewicz Krzysztof Lewiński 《Transition Metal Chemistry》2006,31(3):353-361
The single crystal X-ray structure of (AsPh4)[W(bpy)(CN)6] is described. The structure of octa- and hepta-coordinated intermediates of substitutional photolysis of [Mo(CN)8]4− ion in aqueous media were determined by performing semi-empirical calculations. On the basis of obtained results as well
as on empirical data the photolysis scheme has been postulated. 相似文献
9.
Tomasz Rolski 《Probability Theory and Related Fields》1990,84(1):27-37
Summary We discuss in this paper a non-homogeneous Poisson process A driven by an almost periodic intensity function. We give the stationary version A
* and the Palm version A
0 corresponding to A
*. Let (T
i
,i) be the inter-point distance sequence in A and (T
i
0
,i) in A
0. We prove that forj, the sequence (T
i+j,i) converges in distribution to (T
i
0
,i). If the intensity function is periodic then the convergence is in variation. 相似文献
10.
Let (E, ¦·¦) be a uniformly convex Banach space with the modulus of uniform convexity of power type. Let be the convolution of the distribution of a random series inE with independent one-dimensional components and an arbitrary probability measure onE. Under some assumptions about the components and the smoothness of the norm we show that there exists a constant such that |{·<t}–{·+r<t}|r
q
, whereq depends on the properties of the norm. We specify it in the case ofL
spaces, >1. 相似文献