全文获取类型
收费全文 | 6314篇 |
免费 | 508篇 |
国内免费 | 904篇 |
专业分类
化学 | 2691篇 |
晶体学 | 26篇 |
力学 | 469篇 |
综合类 | 84篇 |
数学 | 3375篇 |
物理学 | 1081篇 |
出版年
2024年 | 11篇 |
2023年 | 72篇 |
2022年 | 110篇 |
2021年 | 146篇 |
2020年 | 175篇 |
2019年 | 186篇 |
2018年 | 179篇 |
2017年 | 181篇 |
2016年 | 206篇 |
2015年 | 175篇 |
2014年 | 281篇 |
2013年 | 507篇 |
2012年 | 283篇 |
2011年 | 321篇 |
2010年 | 274篇 |
2009年 | 394篇 |
2008年 | 424篇 |
2007年 | 435篇 |
2006年 | 408篇 |
2005年 | 333篇 |
2004年 | 316篇 |
2003年 | 300篇 |
2002年 | 284篇 |
2001年 | 243篇 |
2000年 | 269篇 |
1999年 | 164篇 |
1998年 | 163篇 |
1997年 | 148篇 |
1996年 | 133篇 |
1995年 | 122篇 |
1994年 | 90篇 |
1993年 | 75篇 |
1992年 | 63篇 |
1991年 | 53篇 |
1990年 | 32篇 |
1989年 | 15篇 |
1988年 | 26篇 |
1987年 | 24篇 |
1986年 | 20篇 |
1985年 | 17篇 |
1984年 | 18篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1981年 | 7篇 |
1980年 | 8篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1976年 | 5篇 |
1959年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有7726条查询结果,搜索用时 0 毫秒
1.
本文首先将文[1]中的BLD映射推广为弱(L1,L2)-BLD映射,并证明了如下正则性结果:存在两个可积指数 P1=P1(n,L1,L2)<n<q1=q1(n,L1,L2),使得对任意弱(L1,L2)-BLD映射f∈(Ω,Rn),都有f∈(Ω,Rn),即f为(L1,L2)-BLD映射. 相似文献
2.
M. Castagnino R. Id Betan R. Laura 《International Journal of Theoretical Physics》2003,42(10):2423-2439
By extending the notion of mixed states to functionals acting on the space of observables with diagonal singularity we obtain a well-defined complex spectral decomposition of the time evolution for a quantum decaying system. In this formalism, generalized Gamow states are obtained with well-defined physical properties. 相似文献
3.
Hubert Grudziński 《Reports on Mathematical Physics》2004,53(2):317-328
The eigenvalues and eigenfunctions of an elementary 3-fermion 2-body operator 3P2g∧I1A3∑1≤i≤j≤3P2g(i, j)A3 acting on a 3-particle antisymmetric finite-dimensional Hilbert space have been found. Here Pg2 denotes the projection operator onto a 2-particle antisymmetric function g2, while A3 denotes the 3-particle antisymmetrizing operator. 相似文献
4.
Mats Gyllenberg 《Journal of Differential Equations》2004,205(1):50-76
For time-periodic dissipative and irreducible type-K competitive Kolmogorov systems, it is proved that there is a canonically defined countable family F of unordered, disjoint invariant sets with the property that, for every persistent trajectory whose ω-limit set is not a cycle, there exists a unique trajectory in some element of F such that these two trajectories are asymptotic and the corresponding points in these two trajectories are K-related. 相似文献
5.
Takeshi Murashige Hideo Fujikake Hiroto Sato Hiroshi Kikuchi Taiichiro Kurita Fumio Sato 《Optical Review》2004,11(6):349-352
We have confirmed light diffraction of aligned polymer fibers obtained by a phase separation of an anisotropic-phase solution of liquid crystal and polymer. He—Ne laser light passing through the polymer fibers was scattered in the axis vertical to the fibers, and had two peaks of light intensity symmetrical to the center of the transmitting laser spot. The two peaks were found to be caused by light diffraction due to the periodic polymer-fiber dispersion because the peaks corresponded to values calculated by intervals between the fibers. The periodical fiber networks are considered to be formed by anisotropic spinodal decomposition. This effect can be used to measure the dispersion order of the polymer fibers. © 2004 The Optical Society of Japan 相似文献
6.
This paper presents a unified analysis of decomposition algorithms for continuously differentiable optimization problems defined on Cartesian products of convex feasible sets. The decomposition algorithms are analyzed using the framework of cost approx imation algorithms. A convergence analysis is made for three decomposition algorithms: a sequential algorithm which extends the classical Gauss-Seidel scheme, a synchronized parallel algorithm which extends the Jacobi method, and a partially asynchronous parallel algorithm. The analysis validates inexact computations in both the subproblem and line search phases, and includes convergence rate results. The range of feasible step lengths within each algorithm is shown to have a direct correspondence to the increasing degree of parallelism and asynchronism, and the resulting usage of more outdated information in the algorithms. 相似文献
7.
A complete study of the spectrum of a finite-dimensional Bose operator is carried out in the paper. The cases in which the
spectrum is discrete or continuous are studied.
Translated fromMatematicheskie Zametki, Vol. 61, No. 6, pp. 835–854, June, 1997.
Translated by A. M. Chebotarev 相似文献
8.
H. R. Ebrahimi-Vishki M. A. Pourabdollah 《Proceedings of the American Mathematical Society》1997,125(7):2171-2174
The purpose of this paper is to introduce an algebra of functions on a semitopological semigroup and to study these functions from the point of view of universal semigroup compactification. We show that the corresponding semigroup compactification of this algebra is universal with respect to the property of being a nilpotent group.
9.
本文给出了Banach空间广义分解定理的一个初等证明,并利用它来证明两个对称不等式.这是首次在Banach空间获得这样的不等式. 相似文献
10.
J. MALINEN O. NEVANLINNA V. TURUNEN Z. YUAN 《数学学报(英文版)》2007,23(4):745-748
Let T be a bounded linear operator in a Banach space, with σ(T)={1}. In 1983, Esterle-Berkani' s conjecture was proposed for the decay of differences (I - T) T^n as follows: Eitheror lim inf (n→∞(n+1)||(I-T)T^n||≥1/e or T = I. We prove this claim and discuss some of its consequences. 相似文献