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   14904篇
  免费   1123篇
  国内免费   768篇
化学   1448篇
晶体学   21篇
力学   868篇
综合类   216篇
数学   12234篇
物理学   2008篇
  2023年   82篇
  2022年   131篇
  2021年   200篇
  2020年   225篇
  2019年   260篇
  2018年   264篇
  2017年   359篇
  2016年   387篇
  2015年   284篇
  2014年   645篇
  2013年   955篇
  2012年   802篇
  2011年   691篇
  2010年   672篇
  2009年   882篇
  2008年   957篇
  2007年   1011篇
  2006年   796篇
  2005年   731篇
  2004年   599篇
  2003年   541篇
  2002年   571篇
  2001年   506篇
  2000年   458篇
  1999年   422篇
  1998年   348篇
  1997年   316篇
  1996年   317篇
  1995年   298篇
  1994年   220篇
  1993年   206篇
  1992年   203篇
  1991年   180篇
  1990年   139篇
  1989年   106篇
  1988年   113篇
  1987年   91篇
  1986年   106篇
  1985年   136篇
  1984年   109篇
  1983年   34篇
  1982年   69篇
  1981年   54篇
  1980年   50篇
  1979年   47篇
  1978年   58篇
  1977年   60篇
  1976年   34篇
  1975年   15篇
  1974年   16篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Understanding the solution of a problem may require the reader to have background knowledge on the subject. For instance, finding an integer which, when divided by a nonzero integer leaves a remainder; but when divided by another nonzero integer may leave a different remainder. To find a smallest positive integer or a set of integers following the given conditions, one may need to understand the concept of modulo arithmetic in number theory. The Chinese Remainder Theorem is a known method to solve these types of problems using modulo arithmetic. In this paper, an efficient remainder rule has been proposed based on basic mathematical concepts. These core concepts are as follows: basic remainder rules of divisions, linear equation in slope intercept form, arithmetic progression and the use of a graphing calculator. These are easily understood by students who have taken prealgebra or intermediate algebra.  相似文献   
62.
《Mathematische Nachrichten》2017,290(16):2560-2566
In this paper, we describe a second main theorem of holomorphic curves in , of hyper‐order strictly less than 1, that involves a general linear operator . As an application, we derive a truncated second main theorem of degenerate holomorphic curves of hyper‐order strictly less than 1 using Nochka weights.  相似文献   
63.
Assume a fixed point vVG can be separated from zero by a homogeneous invariant f∈𝕜[V]G of degree prd, where p>0 is the characteristic of the ground field 𝕜 and p,d are coprime. We show that then v can also be separated from zero by an invariant of degree pr, which we obtain explicitly from f. It follows that the minimal degree of a homogeneous invariant separating v from zero is a p-power.  相似文献   
64.
65.
This paper is concerned with Hölder continuity of the solution to a saddle point problem. Some new su?cient conditions for the uniqueness and Hölder continuity of the solution for a perturbed saddle point problem are established. Applications of the result on Hölder continuity of the solution for perturbed constrained optimization problems are presented under mild conditions. Examples are given to illustrate the obtained results.  相似文献   
66.
This paper presents a nonmonotone inexact Newton-type method for the extended linear complementarity problem (ELCP). We first reformulate the optimization system of the ELCP problem into a system of smoothed equations. Then we solve this system by a nonmonotone inexact Newton-type algorithm. The global convergence is obtained and numerical tests for some classes of ELCP include linear complementarity, horizontal linear complementarity, and generalized linear complementarity problems are also given to show the e?ciency of the proposed algorithm.  相似文献   
67.
68.
In [1 Bannai, E. (1991). Subschemes of some association schemes. J. Algebra 14:167188.[Crossref], [Web of Science ®] [Google Scholar]], Bannai presents a fusion condition and uses this to consider central Schur rings (S-rings) over the simple groups PSL(2,q) where q is a prime power. In this paper, we concretely describe all such S-rings in terms of symmetric S-rings over cyclic groups. The final section discusses counting these.  相似文献   
69.
We investigate the correctness of the initial boundary value problem of longitudinal impact on a piecewise‐homogeneous semi‐infinite bar consisting of a semi‐infinite elastic part and finite length visco‐elastic part whose hereditary properties are described by linear integral relations with an arbitrary difference kernel. Introducing nonstationary regularization in boundary conditions and in the contact conditions, the well‐posedness of the considered problem is proved. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
70.
Synchronization of complex networks with time‐varying coupling matrices is studied in this paper. Two kinds of time‐varying coupling are taken into account. One is the time‐varying inner coupling in the node state space and the other is the time‐varying outer coupling in the network topology space. By respectively setting linear controllers and adaptive controllers, time‐varying complex networks can be synchronized to a desired state. Meanwhile, different influences of the control parameters of linear controllers and adaptive controllers on the synchronization have also been investigated. Based on the Lyapunov function theory, we construct appropriate positive‐definite functions, and several sufficient synchronization criteria are obtained. Numerical simulations further illustrate the effectiveness of conclusions. Copyright © 2017 John Wiley & Sons, Ltd.  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