全文获取类型
收费全文 | 9273篇 |
免费 | 263篇 |
国内免费 | 231篇 |
专业分类
化学 | 1560篇 |
晶体学 | 69篇 |
力学 | 44篇 |
综合类 | 20篇 |
数学 | 6868篇 |
物理学 | 1206篇 |
出版年
2023年 | 40篇 |
2022年 | 58篇 |
2021年 | 68篇 |
2020年 | 79篇 |
2019年 | 196篇 |
2018年 | 180篇 |
2017年 | 119篇 |
2016年 | 105篇 |
2015年 | 162篇 |
2014年 | 250篇 |
2013年 | 414篇 |
2012年 | 316篇 |
2011年 | 530篇 |
2010年 | 449篇 |
2009年 | 586篇 |
2008年 | 588篇 |
2007年 | 674篇 |
2006年 | 522篇 |
2005年 | 344篇 |
2004年 | 291篇 |
2003年 | 278篇 |
2002年 | 261篇 |
2001年 | 201篇 |
2000年 | 198篇 |
1999年 | 244篇 |
1998年 | 247篇 |
1997年 | 210篇 |
1996年 | 197篇 |
1995年 | 246篇 |
1994年 | 209篇 |
1993年 | 205篇 |
1992年 | 177篇 |
1991年 | 104篇 |
1990年 | 103篇 |
1989年 | 128篇 |
1988年 | 74篇 |
1987年 | 62篇 |
1986年 | 60篇 |
1985年 | 87篇 |
1984年 | 77篇 |
1983年 | 56篇 |
1982年 | 73篇 |
1981年 | 49篇 |
1980年 | 52篇 |
1979年 | 47篇 |
1978年 | 56篇 |
1977年 | 28篇 |
1976年 | 29篇 |
1975年 | 12篇 |
1974年 | 10篇 |
排序方式: 共有9767条查询结果,搜索用时 15 毫秒
21.
S. Pumplün 《manuscripta mathematica》1998,97(1):93-108
For a Brauer–Severi variety X over a field k of characteristic not two, every symmetric bilinear space over X up to Witt equivalence is defined over k.
Received: 2 February 1998 相似文献
22.
23.
We shall give a direct proof of the independence result of a Buchholz style-Hydra Game on labeled finite trees. We shall
show that Takeuti-Arai's cut-elimination procedure of and of the iterated inductive definition systems can be directly expressed by the reduction rules of Buchholz's Hydra Game.
As a direct corollary the independence result of the Hydra Game follows.
Received: August 23, 1994 / Revised: July 24, 1995 and May 9, 1996 相似文献
24.
Modifying complex plane rotations, we derive a new Jacobi-type algorithm for the Hermitian eigendecomposition, which uses only real arithmetic. When the fast-scaled rotations are incorporated, the new algorithm brings a substantial reduction in computational costs. The new method has the same convergence properties and parallelism as the symmetric Jacobi algorithm. Computational test results show that it produces accurate eigenvalues and eigenvectors and achieves great reduction in computational time.The work of this author was supported in part by the National Science Foundation grant CCR-8813493 and by the University of Minnesota Army High Performance Computing Research Center contract DAAL 03-89-C-0038.The work of this author was supported in part by the University of Minnesota Army High Performance Computing Research Center contract DAAL 03-89-C-0038. 相似文献
25.
Summary. We study a diffusion model of an interacting particles system with general drift and diffusion coefficients, and electrostatic
inter-particles repulsion. More precisely, the finite particle system is shown to be well defined thanks to recent results
on multivalued stochastic differential equations (see [2]), and then we consider the behaviour of this system when the number
of particles goes to infinity (through the empirical measure process). In the particular case of affine drift and constant diffusion coefficient,
we prove that a limiting measure-valued process exists and is the unique solution of a deterministic PDE. Our treatment of
the convergence problem (as ) is partly similar to that of T. Chan [3] and L.C.G. Rogers - Z. Shi [5], except we consider here a more general case allowing
collisions between particles, which leads to a second-order limiting PDE.
Received: 5 August 1996 / In revised form: 17 October 1996 相似文献
26.
27.
H. Stetkær 《Aequationes Mathematicae》1997,54(1-2):144-172
Summary We produce complete solution formulas of selected functional equations of the formf(x +y) ±f(x + σ (ν)) = Σ
I
2
=1
g
l
(x)h
l
(y),x, y∈G, where the functionsf,g
1,h
1 to be determined are complex valued functions on an abelian groupG and where σ:G→G is an involution ofG. The special case of σ=−I encompasses classical functional equations like d’Alembert’s, Wilson’s first generalization of it, Jensen’s equation and
the quadratic equation. We solve these equations, the equation for symmetric second differences in product form and similar
functional equations for a general involution σ. 相似文献
28.
29.
Kevin Houston 《Inventiones Mathematicae》2002,147(3):471-485
The disentanglement of certain augmentations is shown to be the topological join of a disentanglement and a Milnor fibre.
The kth disentanglement of a finite map is defined and for corank 1 maps from ℂ
n
to ℂ
n
+1 it is shown that they are homotopically equivalent to a wedge of spheres. Applications to the Mond conjecture are given.
Oblatum 24-VII-2000 & 5-VII-2001?Published online: 12 October 2001 相似文献
30.