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   1133篇
  免费   103篇
  国内免费   135篇
化学   30篇
力学   32篇
综合类   13篇
数学   1267篇
物理学   29篇
  2024年   3篇
  2023年   22篇
  2022年   14篇
  2021年   28篇
  2020年   51篇
  2019年   60篇
  2018年   54篇
  2017年   52篇
  2016年   45篇
  2015年   39篇
  2014年   63篇
  2013年   135篇
  2012年   51篇
  2011年   38篇
  2010年   41篇
  2009年   57篇
  2008年   74篇
  2007年   70篇
  2006年   56篇
  2005年   50篇
  2004年   33篇
  2003年   48篇
  2002年   48篇
  2001年   28篇
  2000年   30篇
  1999年   41篇
  1998年   25篇
  1997年   33篇
  1996年   10篇
  1995年   19篇
  1994年   10篇
  1993年   7篇
  1992年   3篇
  1991年   3篇
  1990年   4篇
  1989年   2篇
  1987年   1篇
  1986年   1篇
  1985年   5篇
  1984年   6篇
  1983年   2篇
  1982年   2篇
  1981年   1篇
  1979年   2篇
  1978年   2篇
  1977年   2篇
排序方式: 共有1371条查询结果,搜索用时 62 毫秒
81.
In this paper, we study error bounds for lower semicontinuous functions defined on Banach space and linear regularity for finitely many closed subset in Banach spaces. By using Clarke's subd- ifferentials and Ekeland variational principle, we establish several sufficient conditions ensuring error bounds and linear regularity in Banach spaces.  相似文献   
82.
For Ω a bounded subset of R n,n 2,ψ any function in Ω with values in R∪{±∞}andθ∈W1,(q i)(Ω),let K(q i)ψ,θ(Ω)={v∈W1,(q i)(Ω):vψ,a.e.and v-θ∈W1,(q i)0(Ω}.This paper deals with solutions to K(q i)ψ,θ-obstacle problems for the A-harmonic equation-divA(x,u(x),u(x))=-divf(x)as well as the integral functional I(u;Ω)=Ωf(x,u(x),u(x))dx.Local regularity and local boundedness results are obtained under some coercive and controllable growth conditions on the operator A and some growth conditions on the integrand f.  相似文献   
83.
We prove that the regularity of a vertex operator superalgebra can be reduced to the semisimplicity of the category of its weak modules.Moreover,the rationality can be replaced by requiring that each 1/2Z+-graded module is a direct sum of irreducible weak modules.  相似文献   
84.
85.
86.
87.
ABSTRACT

A simple analytical expression is derived to calculate the thermal pressure coefficients of liquid alkali metals. First, a modified linear isothermal regularity is applied to calculate the thermal pressure coefficients for caesium (Cs) and rubidium (Rb) in different thermodynamic states. The results obtained show that the calculated thermal pressure coefficients increase with increase in the density and decrease in the temperature. The extent of deviation between the calculated thermal pressure coefficients from the modified regularity and experimental values reduce remarkably with respect to those obtained from the primary isothermal regularity. Secondly, the thermal pressure coefficients are determined by the accurate dense fluid theory for a hard-sphere system. A comparative study of the predicted thermal pressure coefficients for both Cs and Rb shows that the results obtained by the isothermal regularity theory are closer to the experimental data with respect to the ones obtained from the statistical thermodynamic method.  相似文献   
88.
We consider a coupled system describing nonlinear Darcy flows with temperature dependent viscosity and with viscous heating. We first establish existence, uniqueness, and regularity of the weak solution of the system of equations. Next, we decouple the coupled system by a fixed point algorithm and propose its finite element approximation. Finally, we present convergence analysis with an error estimate between continuous solution and its iterative finite element approximation.© 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010  相似文献   
89.
In this paper, we exclude the possibility of existence of a singular solution of the selfsimilar type proposed by Jean Leray More precisely, using a slightly stronger hypothesis we give a simpler proof to the analogous result established by J. Ne?as, M. Rú?i?ka and V. ?verák. We also discuss the possible existence of a singular solution of pseudo-selfsimilar type.  相似文献   
90.
An analogue of the Kunz–Frobenius criterion for the regularity of a local ring in a positive characteristic is established for general commutative semigroup rings.  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