首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2645篇
  免费   101篇
  国内免费   192篇
化学   7篇
力学   74篇
综合类   39篇
数学   2578篇
物理学   240篇
  2023年   27篇
  2022年   13篇
  2021年   39篇
  2020年   27篇
  2019年   55篇
  2018年   49篇
  2017年   60篇
  2016年   44篇
  2015年   47篇
  2014年   81篇
  2013年   201篇
  2012年   86篇
  2011年   96篇
  2010年   85篇
  2009年   143篇
  2008年   190篇
  2007年   181篇
  2006年   140篇
  2005年   130篇
  2004年   102篇
  2003年   113篇
  2002年   135篇
  2001年   86篇
  2000年   104篇
  1999年   75篇
  1998年   77篇
  1997年   79篇
  1996年   53篇
  1995年   57篇
  1994年   34篇
  1993年   31篇
  1992年   30篇
  1991年   22篇
  1990年   28篇
  1989年   17篇
  1988年   20篇
  1987年   20篇
  1986年   14篇
  1985年   19篇
  1984年   17篇
  1983年   7篇
  1982年   21篇
  1981年   16篇
  1980年   10篇
  1979年   14篇
  1978年   9篇
  1977年   15篇
  1976年   8篇
  1975年   3篇
  1974年   3篇
排序方式: 共有2938条查询结果,搜索用时 312 毫秒
21.
In this paper, we review and unify some classes of generalized convex functions introduced by different authors to prove minimax results in infinite-dimensional spaces and show the relations between these classes. We list also for the most general class already introduced by Jeyakumar (Ref. 1) an elementary proof of a minimax result. The proof of this result uses only a finite-dimensional separa- tion theorem; although this minimax result was already presented by Neumann (Ref. 2) and independently by Jeyakumar (Ref. 1), we believe that the present proof is shorter and more transparent.  相似文献   
22.
23.
A logarithmic Sobolev trace inequality is derived. Bounds on the best constant for this inequality from above and below are investigated using the sharp Sobolev inequality and the sharp logarithmic Sobolev inequality.

  相似文献   

24.
We show by general considerations that it is not possible to test violation of the existing versions of Bell’s inequality in entangled neutral kaons system using experimentally accessible thin regenerators. We point out the loophole in the recent argument (A Bramon and M Nowakowski, Phys. Rev. Lett. 83, 1 (1999)) that claimed such a test to be possible.  相似文献   
25.
We provide some inequalities and integral inequalities connected to the Jensen-Hadamard inequalities for convex functions. In particular, we give some refinements to these inequalities. Some natural applications and further extensions are given.
Sunto Forniamo alcune diseguaglianze e diseguaglianze integrali connesse alle dise-gueglianze di Jensen-Hadamard per funzioni convesse. In particolare, diamo qualche miglioramento di queste diseguaglianze. Alcune applicazioni naturali ed ulteriori estensioni sono date.
  相似文献   
26.
We propose general variational inclusion problems which are slightly different from corresponding problems considered in several recent papers in the literature and show that they are advantageous. Sufficient conditions for the solution existence are established. As applications we derive consequences for several special cases of variational inclusion problems, quasioptimization problems, equilibrium problems and implicit variational inequalities and show that they improve the results of some recent existing papers.  相似文献   
27.
This paper deals with a model of time-dependent double diffusive convection in Darcy flow. In particular it is concerned with the spatial decay of solutions when the flow is confined to a semi-infinite cylinder. Decay bounds for an energy expression are derived.  相似文献   
28.
本文研究了独立随机变量之和的绝对矩的几个性质, 其中包括$\ep|X+Y|-\ep|X-Y|$的表达式, 这里$X$和$Y$是相互独立的随机变量.  相似文献   
29.
The BCQ and the Abadie CQ for infinite systems of convex inequalities in Banach spaces are characterized in terms of the upper semi-continuity of the convex cones generated by the subdifferentials of active convex functions. Some relationships with other constraint qualifications such as the CPLV and the Slate condition are also studied. Applications in best approximation theory are provided.  相似文献   
30.
Sedimentation and erosion processes in sedimentary basins can be modeled by a parabolic equation with a limiter on the fluxes and a constraint on the time variation.This limiter happens to satisfy a stationary scalar hyperbolic inequality,within a constraint,for which the authors prove the existence and the uniqueness of the solution.Actually,this solution is shown to be the maximal element of a convenient convex set of functions.The existence proof is obtained thanks to the use of a numerical scheme.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号