全文获取类型
收费全文 | 6781篇 |
免费 | 850篇 |
国内免费 | 671篇 |
专业分类
化学 | 313篇 |
晶体学 | 1篇 |
力学 | 805篇 |
综合类 | 174篇 |
数学 | 5728篇 |
物理学 | 1281篇 |
出版年
2024年 | 13篇 |
2023年 | 58篇 |
2022年 | 94篇 |
2021年 | 103篇 |
2020年 | 158篇 |
2019年 | 161篇 |
2018年 | 206篇 |
2017年 | 235篇 |
2016年 | 249篇 |
2015年 | 163篇 |
2014年 | 271篇 |
2013年 | 595篇 |
2012年 | 308篇 |
2011年 | 371篇 |
2010年 | 347篇 |
2009年 | 400篇 |
2008年 | 480篇 |
2007年 | 444篇 |
2006年 | 435篇 |
2005年 | 392篇 |
2004年 | 350篇 |
2003年 | 308篇 |
2002年 | 315篇 |
2001年 | 226篇 |
2000年 | 252篇 |
1999年 | 192篇 |
1998年 | 178篇 |
1997年 | 163篇 |
1996年 | 115篇 |
1995年 | 132篇 |
1994年 | 86篇 |
1993年 | 83篇 |
1992年 | 62篇 |
1991年 | 46篇 |
1990年 | 52篇 |
1989年 | 34篇 |
1988年 | 22篇 |
1987年 | 22篇 |
1986年 | 24篇 |
1985年 | 19篇 |
1984年 | 20篇 |
1983年 | 9篇 |
1982年 | 19篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1978年 | 14篇 |
1977年 | 13篇 |
1974年 | 7篇 |
1973年 | 7篇 |
排序方式: 共有8302条查询结果,搜索用时 15 毫秒
11.
Equilibrium Problems with Applications to Eigenvalue Problems 总被引:5,自引:0,他引:5
In this paper, we consider equilibrium problems and introduce the concept of (S)+ condition for bifunctions. Existence results for equilibrium problems with the (S)+ condition are derived. As special cases, we obtain several existence results for the generalized nonlinear variational inequality studied by Ding and Tarafdar (Ref. 1) and the generalized variational inequality studied by Cubiotti and Yao (Ref. 2). Finally, applications to a class of eigenvalue problems are given. 相似文献
12.
P.A. Grillet 《Acta Mathematica Hungarica》2005,106(4):301-315
Summary Three weak variants of compactness which lie strictly between compactness and quasicompactness, are introduced. Their basic properties are studied. The interplay with mapping and their direct and inverse preservation under mappings are investigated. In the process three decompositions of compactness are observed. 相似文献
13.
14.
本文考察了包括平面上的各种广义 Cantor集 ,Sierpinski集和包括某些连续不可微曲线在内的广义 Sierpinski集 .由相似变换 ,导出了它们的级数表达式 ,并利用它和字符串空间的对应关系 ,计算出它们的Hausdorff维数 相似文献
15.
CONG Fuzhong & LI YongSchool of Mathematics Information Science Shandong Institute of Business Technology Yantai China Office of Mathematics Changchun Flight Academy of the Air Force Changchun China Department of Mathematics Jilin University Changchun China 《中国科学A辑(英文版)》2004,47(5):675-686
An effective stability result for generalized Hamiltonian systems is obtained by applying the simultaneous approximation technique due to Lochak. Among these systems, dimensions of action variables and angle variables might be distinct. 相似文献
16.
令H是有限维Hopf代数,A是左H-模代数。本文证明了A是Gorenstein代数的充分必要条件。A^H也是Gorenstein代数的条件。它是Enochs EE,GarciaJJ和del RioA关于群作用相应的理论的推广,同时给出A/A^H是Frobenius扩张的条件。 相似文献
17.
18.
We study initial boundary value problems for linear scalar evolutionpartial differential equations, with spatial derivatives ofarbitrary order, posed on the domain {t > 0, 0 < x <L}. We show that the solution can be expressed as an integralin the complex k-plane. This integral is defined in terms ofan x-transform of the initial condition and a t-transform ofthe boundary conditions. The derivation of this integral representationrelies on the analysis of the global relation, which is an algebraicrelation defined in the complex k-plane coupling all boundaryvalues of the solution. For particular cases, such as the case of periodic boundaryconditions, or the case of boundary value problems for even-orderPDEs, it is possible to obtain directly from the global relationan alternative representation for the solution, in the formof an infinite series. We stress, however, that there existinitial boundary value problems for which the only representationis an integral which cannot be written as an infinite series.An example of such a problem is provided by the linearized versionof the KdV equation. Similarly, in general the solution of odd-orderlinear initial boundary value problems on a finite intervalcannot be expressed in terms of an infinite series. 相似文献
19.
20.
For vector quasivariational inequalities involving multifunctions in topological vector spaces, an existence result is obtained without a monotonicity assumption and with a convergence assumption weaker than semicontinuity. A new type of quasivariational inequality is proposed. Applications to quasicomplementarity problems and traffic network equilibria are considered. In particular, definitions of weak and strong Wardrop equilibria are introduced for the case of multivalued cost functions. 相似文献