全文获取类型
收费全文 | 7874篇 |
免费 | 668篇 |
国内免费 | 1074篇 |
专业分类
化学 | 83篇 |
力学 | 220篇 |
综合类 | 182篇 |
数学 | 7922篇 |
物理学 | 1209篇 |
出版年
2024年 | 14篇 |
2023年 | 76篇 |
2022年 | 84篇 |
2021年 | 120篇 |
2020年 | 170篇 |
2019年 | 224篇 |
2018年 | 221篇 |
2017年 | 230篇 |
2016年 | 252篇 |
2015年 | 170篇 |
2014年 | 377篇 |
2013年 | 596篇 |
2012年 | 322篇 |
2011年 | 460篇 |
2010年 | 449篇 |
2009年 | 627篇 |
2008年 | 586篇 |
2007年 | 624篇 |
2006年 | 523篇 |
2005年 | 469篇 |
2004年 | 394篇 |
2003年 | 417篇 |
2002年 | 380篇 |
2001年 | 249篇 |
2000年 | 285篇 |
1999年 | 274篇 |
1998年 | 230篇 |
1997年 | 214篇 |
1996年 | 134篇 |
1995年 | 68篇 |
1994年 | 65篇 |
1993年 | 38篇 |
1992年 | 35篇 |
1991年 | 23篇 |
1990年 | 16篇 |
1989年 | 18篇 |
1988年 | 19篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 15篇 |
1984年 | 26篇 |
1983年 | 14篇 |
1982年 | 23篇 |
1981年 | 14篇 |
1980年 | 20篇 |
1979年 | 11篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 3篇 |
1936年 | 4篇 |
排序方式: 共有9616条查询结果,搜索用时 15 毫秒
991.
992.
Banach空间二阶非线性奇异微分方程的解 总被引:11,自引:0,他引:11
周友明 《数学物理学报(A辑)》2000,20(2):181-186
文中讨论了Banach空间中一类右端具有奇异性的二阶非线性微分方程的边值问题,利用不动点方法,获得了该边值问题解的存在性定理.最后还给出了相应的例子. 相似文献
993.
《Journal of the Egyptian Mathematical Society》2014,22(1):36-44
By making use of the principle of subordination between analytic functions and the generalized fractional differintegral operator, we introduce and investigate some new subclasses of p-valently analytic functions in the open unit disk. Such results as inclusion relationships, integral-preserving properties, convolution properties, subordination and superordination properties, and sandwich theorems for these classes are derived. 相似文献
994.
《佛山科学技术学院》2014,6(4):435-450
In the present paper, self-adjoint operator and completely continuous operator on soft inner product spaces have been introduced and some basic properties of such operators are studied. 相似文献
995.
The present paper extends to higher degrees the well-known separation theorem decomposing a shift in the increasing convex order into a combination of a shift in the usual stochastic order followed by another shift in the convex order. An application in decision making under risk is provided to illustrate the interest of the result. 相似文献
996.
Finite Difference/Collocation Method for Two-Dimensional Sub-Diffusion Equation with Generalized Time Fractional Derivative 下载免费PDF全文
Qinwu Xu & Zhoushun Zheng 《数学研究》2014,47(2):173-189
In this paper, we propose a finite difference/collocation method for two-dimensional time fractional diffusion equation with generalized fractional operator. The main purpose of this paper is to design a high order numerical scheme for the new generalized time fractional diffusion equation. First, a finite difference approximation formula is derived for the generalized time fractional derivative, which is verified with order $2-\alpha$ $(0<\alpha<1)$. Then, collocation method is introduced for the two-dimensional space approximation. Unconditional stability of the scheme is proved. To make the method more efficient, the alternating direction implicit method is introduced to reduce the computational cost. At last, numerical experiments are carried out to verify the effectiveness of the scheme. 相似文献
997.
AbstractIn the present paper, we summarize the recent literature concerning the spectrum and fine spectrum with respect to Goldberg’s classification of some operators represented by an infinite matrix over certain sequence spaces. 相似文献
998.
Kyung-Tae Kang 《Linear and Multilinear Algebra》2013,61(2):241-247
We obtain some characterizations of linear operators that preserve the term rank of Boolean matrices. That is, a linear operator over Boolean matrices preserves the term rank if and only if it preserves the term ranks 1 and k(≠1) if and only if it preserves the term ranks 2 and l(≠2). Other characterizations of term rank preservers are given. 相似文献
999.
1000.