全文获取类型
收费全文 | 2825篇 |
免费 | 377篇 |
国内免费 | 417篇 |
专业分类
化学 | 304篇 |
晶体学 | 19篇 |
力学 | 350篇 |
综合类 | 79篇 |
数学 | 1903篇 |
物理学 | 964篇 |
出版年
2024年 | 5篇 |
2023年 | 20篇 |
2022年 | 32篇 |
2021年 | 53篇 |
2020年 | 57篇 |
2019年 | 55篇 |
2018年 | 57篇 |
2017年 | 70篇 |
2016年 | 68篇 |
2015年 | 65篇 |
2014年 | 97篇 |
2013年 | 303篇 |
2012年 | 114篇 |
2011年 | 140篇 |
2010年 | 122篇 |
2009年 | 134篇 |
2008年 | 190篇 |
2007年 | 196篇 |
2006年 | 184篇 |
2005年 | 144篇 |
2004年 | 148篇 |
2003年 | 170篇 |
2002年 | 147篇 |
2001年 | 148篇 |
2000年 | 141篇 |
1999年 | 117篇 |
1998年 | 135篇 |
1997年 | 92篇 |
1996年 | 79篇 |
1995年 | 61篇 |
1994年 | 66篇 |
1993年 | 34篇 |
1992年 | 26篇 |
1991年 | 21篇 |
1990年 | 28篇 |
1989年 | 15篇 |
1988年 | 14篇 |
1987年 | 13篇 |
1986年 | 12篇 |
1985年 | 3篇 |
1984年 | 23篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1978年 | 2篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1959年 | 1篇 |
1936年 | 2篇 |
排序方式: 共有3619条查询结果,搜索用时 640 毫秒
11.
M. A. Efendiev J. Fuhrmann S. V. Zelik 《Mathematical Methods in the Applied Sciences》2004,27(8):907-930
For the Boussinesq approximation of the equations of coupled heat and fluid flow in a porous medium we show that the corresponding system of partial differential equations possesses a global attractor. We give lower and upper bounds of the Hausdorff dimension of the attractor depending on a physical parameter of the system, namely the Rayleigh number of the flow. Numerical experiments confirm the theoretical findings and raise new questions on the structure of the solutions of the system. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
12.
13.
A. Debussche 《Journal de Mathématiques Pures et Appliquées》1998,77(10):967-988
The notion of random attractor for a dissipative stochastic dynamical system has recently been introduced. It generalizes the concept of global attractor in the deterministic theory. It has been shown that many stochastic dynamical systems associated to a dissipative partial differential equation perturbed by noise do possess a random attractor. In this paper, we prove that, as in the case of the deterministic attractor, the Hausdorff dimension of the random attractor can be estimated by using global Lyapunov exponents. The result is obtained under very natural assumptions. As an application, we consider a stochastic reaction-diffusion equation and show that its random attractor has finite Hausdorff dimension. 相似文献
14.
Gr-凝聚环的分次FP-内射维数 总被引:4,自引:0,他引:4
引进了分次FP-内射维数,对Gr-凝聚环的分次FP-内射维数作了刻划,将Stentrom等人的若干工作推广到分次环上. 相似文献
15.
Understanding of the basic nature of arc root fluctuation is still one of the unsolved problems in thermal arc plasma physics.
It has direct impact on myriads of thermal plasma applications being implemented at present. Recently, chaotic nature of arc
root behavior has been reported through the analysis of voltages, acoustic and optical signals which are generated from a
hollow copper electrode arc plasma torch. In this paper we present details of computations involved in the estimation process
of various dynamic properties and show how they reflect chaotic behavior of arc root in the system. 相似文献
16.
O. Yu. Dashkova 《Algebra and Logic》2007,46(5):297-302
We are concerned with infinite-dimensional locally soluble linear groups of infinite central dimension that are not soluble
A3-groups and all of whose proper subgroups, which are not soluble A3-groups, have finite central dimension. The structure of groups in this class is described. The case of infinite-dimensional
locally nilpotent linear groups satisfying the specified conditions is treated separately. A similar problem is solved for
infinite-dimensional locally soluble linear groups of infinite fundamental dimension that are not soluble A3-groups and all of whose proper subgroups, which are not soluble A3-groups, have finite fundamental dimension.
__________
Translated from Algebra i Logika, Vol. 46, No. 5, pp. 548–559, September–October, 2007. 相似文献
17.
D. V. Artamonov 《Mathematical Notes》2007,81(5-6):573-589
A natural criterion for dimensional full-valuedness of locally compact spaces with finitely generated local homology is given. 相似文献
18.
19.
20.