全文获取类型
收费全文 | 5999篇 |
免费 | 454篇 |
国内免费 | 240篇 |
专业分类
化学 | 1137篇 |
晶体学 | 23篇 |
力学 | 925篇 |
综合类 | 81篇 |
数学 | 3489篇 |
物理学 | 1038篇 |
出版年
2024年 | 16篇 |
2023年 | 72篇 |
2022年 | 103篇 |
2021年 | 123篇 |
2020年 | 149篇 |
2019年 | 161篇 |
2018年 | 150篇 |
2017年 | 167篇 |
2016年 | 193篇 |
2015年 | 160篇 |
2014年 | 254篇 |
2013年 | 569篇 |
2012年 | 283篇 |
2011年 | 305篇 |
2010年 | 232篇 |
2009年 | 356篇 |
2008年 | 376篇 |
2007年 | 390篇 |
2006年 | 293篇 |
2005年 | 261篇 |
2004年 | 249篇 |
2003年 | 182篇 |
2002年 | 176篇 |
2001年 | 162篇 |
2000年 | 155篇 |
1999年 | 129篇 |
1998年 | 137篇 |
1997年 | 112篇 |
1996年 | 106篇 |
1995年 | 75篇 |
1994年 | 72篇 |
1993年 | 57篇 |
1992年 | 69篇 |
1991年 | 36篇 |
1990年 | 34篇 |
1989年 | 34篇 |
1988年 | 21篇 |
1987年 | 29篇 |
1986年 | 29篇 |
1985年 | 16篇 |
1984年 | 28篇 |
1983年 | 17篇 |
1982年 | 22篇 |
1981年 | 19篇 |
1980年 | 21篇 |
1979年 | 21篇 |
1978年 | 17篇 |
1977年 | 12篇 |
1976年 | 17篇 |
1973年 | 8篇 |
排序方式: 共有6693条查询结果,搜索用时 15 毫秒
101.
We investigate which types of asymptotic distributions can be generated by the knots of convergent sequences of interpolatory integration rules. It will turn out that the class of all possible distributions can be described exactly, and it will be shown that the zeros of polynomials that are orthogonal with respect to varying weight functions are good candidates for knots of integration rules with a prescribed asymptotic distribution.Research supported by the Deutsche Forschungsgemeinschaft (AZ: Sta 299/4-2). 相似文献
102.
介绍超大规模集成电路(VLSI)波导(?)互连技术的最新进展,并预测其发展方向,以及如阿解决存在的实际问题。 相似文献
103.
Mark C. Veraar 《Proceedings of the American Mathematical Society》2007,135(5):1477-1486
In this paper we prove the equivalence of decoupling inequalities for stochastic integrals and one-sided randomized versions of the UMD property of a Banach space as introduced by Garling.
104.
Contingent epiderivatives and set-valued optimization 总被引:24,自引:0,他引:24
In this paper we introduce the concept of the contingent epiderivative for a set-valued map which modifies a notion introduced by Aubin [2] as upper contingent derivative. It is shown that this kind of a derivative has important properties and is one possible generalization of directional derivatives in the single-valued convex case. For optimization problems with a set-valued objective function optimality conditions based on the concept of the contingent epiderivative are proved which are necessary and sufficient under suitable assumptions. 相似文献
105.
林支桂 《数学物理学报(B辑英文版)》1998,(3)
1IntroductionInthispaper,weconsidertheinitial-boundaryvalueproblem,where"o(x)isnon-negativesmoothfunctionsatisfying"o.(0)=0,"o.(1)=1'Whenconsideringtheblow-upofsolution,thefollowingproblemarisenaturally:Doesblow-upoccur?Howdoesthesolutionapproachtheblow-uptime'!Andwilersisthehotspotlocated(blow-upset)?WelookattheheatequationwithanonlillearboundaryconditiollHerefiisaboundeddomaininR",p>1isarealnumber.IthasbeenknownforalongtimethattheDroblelil(1.1).(1.2)withAL(~,0)--'no(x)doesnothaveaglobals… 相似文献
106.
本文讨论定义于Banach空间的多目标数学规划,得到一些ε-最优解和(弱)有效解的必要条件,充分条件和必要充分条件。 相似文献
107.
A. M. Popov 《Mathematical Notes》1998,64(3):377-381
For operators corresponding to systems ofμth-order difference-differential equations of neutral type, necessary and sufficient conditions for potentiality with respect
to the classical bilinear form are obtained. These results are applied to first-order quasilinear systems.
Translated fromMatematicheskie Zametki, Vol. 64, No. 3, pp. 437–442, September, 1998.
The author wishes to express his thanks to V. M. Savchin for fruitful discussions and useful remarks. 相似文献
108.
A test statistic is developed that checks the validity of the extreme value conditions without specifiying the shape parameter of the limiting extreme value distribution. 相似文献
109.
We consider a four-dimensional generalization of Hess–Appel’rot system and costruct its Lax pair. Both classical and algebro-geometric integration procedure are proceeded. The algebro-geometric integration is based on deep facts from geometry of Prym varieties such as the Mumford relation and Mumford-Dalalyan theory. The integration is similar to the integration of Lagrange bitop which has recetly been performed by the authors. 相似文献
110.
This paper considers an optimal boundary control problem fora hyperbolic system in which constant time lags appear in thestate equation and in the boundary condition simultaneously.Making use of Lion's scheme, necessary and sufficient conditionsof optimality for the Neumann problem are derived. 相似文献