全文获取类型
收费全文 | 12812篇 |
免费 | 1231篇 |
国内免费 | 1633篇 |
专业分类
化学 | 992篇 |
晶体学 | 27篇 |
力学 | 738篇 |
综合类 | 358篇 |
数学 | 11089篇 |
物理学 | 2472篇 |
出版年
2024年 | 21篇 |
2023年 | 133篇 |
2022年 | 172篇 |
2021年 | 223篇 |
2020年 | 286篇 |
2019年 | 321篇 |
2018年 | 293篇 |
2017年 | 358篇 |
2016年 | 380篇 |
2015年 | 309篇 |
2014年 | 539篇 |
2013年 | 869篇 |
2012年 | 534篇 |
2011年 | 749篇 |
2010年 | 710篇 |
2009年 | 906篇 |
2008年 | 963篇 |
2007年 | 1031篇 |
2006年 | 824篇 |
2005年 | 791篇 |
2004年 | 605篇 |
2003年 | 658篇 |
2002年 | 560篇 |
2001年 | 466篇 |
2000年 | 517篇 |
1999年 | 438篇 |
1998年 | 423篇 |
1997年 | 335篇 |
1996年 | 260篇 |
1995年 | 143篇 |
1994年 | 155篇 |
1993年 | 92篇 |
1992年 | 81篇 |
1991年 | 62篇 |
1990年 | 57篇 |
1989年 | 35篇 |
1988年 | 40篇 |
1987年 | 26篇 |
1986年 | 20篇 |
1985年 | 47篇 |
1984年 | 45篇 |
1983年 | 17篇 |
1982年 | 34篇 |
1981年 | 23篇 |
1980年 | 24篇 |
1979年 | 30篇 |
1978年 | 15篇 |
1977年 | 17篇 |
1976年 | 10篇 |
1936年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
We consider two simple model systems describing effective repulsion in a nonideal Bose gas. The interaction Hamiltonians in these systems can be analytically represented as functions of the occupation number operators for modes with nonzero momenta (p0). One of these models contains an interaction term corresponding to repulsion of bosons with the mode p=0 and ensuring the thermodynamic superstability of the system; the other model does not contain such a term. We use the Bogoliubov–Dirac–Ginibre approximation and the method of correlation inequalities to prove that a Bose condensate can exist in these model systems. Because of the character of interaction, the condensate can be formed in the superstable case for any values of the spatial dimensions, temperature, and positive chemical potentials. 相似文献
912.
Shuhuang Xiang 《Journal of Mathematical Analysis and Applications》2004,290(1):310-315
Let X be a uniformly smooth infinite dimensional Banach space, and (Ω,Σ,μ) be a σ-finite measure space. Suppose that T:X→L∞(Ω,Σ,μ) satisfies
(1−ε)‖x‖?‖Tx‖?‖x‖,∀x∈X, 相似文献
913.
Javad Namazi 《Journal of Mathematical Analysis and Applications》2004,290(2):553-562
Let 1<p<∞, and k,m be positive integers such that 0(k−2m)pn. Suppose ΩRn is an open set, and Δ is the Laplacian operator. We will show that there is a sequence of positive constants cj such that for every f in the Sobolev space Wk,p(Ω), for all xΩ except on a set whose Bessel capacity Bk−2m,p is zero. 相似文献
914.
We study the problem of completely describing the domains that enjoy the generalized multiplicative inequalities of the embedding theorem type. We transfer the assertions for the Sobolev spaces L
p
1() to the function classes that result from the replacement of L
p
() with an ideal space of vector-functions. We prove equivalence of the functional and geometric inequalities between the norms of indicators and the capacities of closed subsets of . The most comprehensible results relate to the case of the rearrangement invariant ideal spaces. 相似文献
915.
We prove that the maximal Fej'er operator is not bounded on the real Hardy spaces H
1, which may be considered over
and
. We also draw corollaries for the corresponding Hardy spaces over
2 and
2.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
916.
Evgenia H. Papageorgiou Nikolaos S. Papageorgiou 《Proceedings of the American Mathematical Society》2004,132(2):429-434
In this paper we study a nonlinear periodic problem driven by the ordinary scalar p-Laplacian and with a Carathéodory nonlinearity. We establish the existence of at least two nontrivial solutions. Our approach is variational based on the smooth critical point theory and using the ``Second Deformation Theorem".
917.
Wlodzimierz Bryc Victor Kaftal 《Proceedings of the American Mathematical Society》2004,132(2):523-534
Bounds for non-commutative versions of two classical strong mixing coefficients for -Gaussian processes are found in terms of the angle between the underlying Hilbert spaces. As a consequence, we construct a -mixing -Gaussian stationary sequence with growth conditions on variances of partial sums. If classical processes with analogous properties were to exist, they would provide a counter-example to the Ibragimov conjecture.
918.
Tavan T. Trent 《Proceedings of the American Mathematical Society》2004,132(8):2429-2432
We find the maximal invariant subspaces for on -valued Bergman-type spaces.
919.
Albin L. Jones 《Proceedings of the American Mathematical Society》2004,132(8):2457-2460
We demonstrate that Martin's axiom for -centered notions of forcing implies the existence of a van der Waerden space that is not a Hindman space. Our proof is an adaptation of the one given by M. Kojman and S. Shelah that such a space exists if one assumes the continuum hypothesis to be true.
920.
Sergei V. Astashkin Lech Maligranda 《Proceedings of the American Mathematical Society》2004,132(10):2929-2938
We show that if is a rearrangement invariant space on that is an interpolation space between and and for which we have only a one-sided estimate of the Boyd index 1/p, 1 < p < \infty$">, then is an interpolation space between and . This gives a positive answer for a question posed by Semenov. We also present the one-sided interpolation theorem about operators of strong type and weak type .