全文获取类型
收费全文 | 7586篇 |
免费 | 458篇 |
国内免费 | 733篇 |
专业分类
化学 | 418篇 |
晶体学 | 6篇 |
力学 | 386篇 |
综合类 | 135篇 |
数学 | 3066篇 |
物理学 | 801篇 |
综合类 | 3965篇 |
出版年
2024年 | 15篇 |
2023年 | 52篇 |
2022年 | 106篇 |
2021年 | 104篇 |
2020年 | 125篇 |
2019年 | 120篇 |
2018年 | 124篇 |
2017年 | 153篇 |
2016年 | 172篇 |
2015年 | 178篇 |
2014年 | 323篇 |
2013年 | 389篇 |
2012年 | 406篇 |
2011年 | 473篇 |
2010年 | 357篇 |
2009年 | 488篇 |
2008年 | 450篇 |
2007年 | 550篇 |
2006年 | 497篇 |
2005年 | 454篇 |
2004年 | 389篇 |
2003年 | 381篇 |
2002年 | 292篇 |
2001年 | 271篇 |
2000年 | 233篇 |
1999年 | 223篇 |
1998年 | 213篇 |
1997年 | 180篇 |
1996年 | 155篇 |
1995年 | 127篇 |
1994年 | 115篇 |
1993年 | 113篇 |
1992年 | 100篇 |
1991年 | 82篇 |
1990年 | 73篇 |
1989年 | 65篇 |
1988年 | 47篇 |
1987年 | 28篇 |
1986年 | 22篇 |
1985年 | 25篇 |
1984年 | 14篇 |
1983年 | 13篇 |
1982年 | 14篇 |
1981年 | 11篇 |
1980年 | 14篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1977年 | 7篇 |
1976年 | 8篇 |
1973年 | 3篇 |
排序方式: 共有8777条查询结果,搜索用时 421 毫秒
91.
THE SCHWARZIAN DERIVATIVE IN SEVERAL COMPLEX VARIABLES(II) 总被引:1,自引:0,他引:1
THESCHWARZIANDERIVATIVEINSEVERALCOMPLEXVARIABLES(II)GONGSHENGYUQIHUANGZHENGXUEANManuscriptreceivedAugust30,1996.De... 相似文献
92.
本文研究弱一致Opial条件的性质;弱一致Opial条件与弱一致Opial条件的对偶性;证明当对偶空间有弱一致Opial条件时该Banach空间具有不动点性. 相似文献
93.
A problem in extremal quasiconformal extensions 总被引:2,自引:0,他引:2
Yi Qi 《中国科学A辑(英文版)》1998,41(11):1135-1141
A constantK
0
(m)
(h) is introduced for every quasisymmetric mappingh of the unit circle and every integerm≥4 which contains the constantK
0(h) (indicated by the change in module of the quadrilaterals with vertices on the circle) as a special case. A necessary and
sufficient condition is established forK
0
(m)
(h) =K
1(h). It is shown that there are infinitely many quasisymmetric mappings of the unit circle having the property thatK
0
(m)
(h)<K
1(h), wherek
1(h) is the maximal dilatation ofh. 相似文献
94.
在集值映射空间中引入了四种图象拓扑,给出它们之间的关系,并在点紧致连续映射空间上证明了其中两种拓扑之间的等价关系. 相似文献
95.
罗元松 《四川大学学报(自然科学版)》2003,40(1):33-35
在Banach空间的框架下,研究了有限族非扩张映象隐迭代程序的收敛性,其结果不仅改进和发展了最新的有关结果,而且也肯定地回答了Xu提出的一个公开问题。 相似文献
96.
L. Mosher 《Commentarii Mathematici Helvetici》1997,72(1):16-29
The quotient of a biautomatic group by a subgroup of the center is shown to be biautomatic. The main tool used is the Neumann-Shapiro
triangulation of S
n-1, associated to a biautomatic structure on . Among other applications, a question of Gersten and Short is settled by showing that direct factors of biautomatic groups
are biautomatic.
Received: October 4, 1994 相似文献
97.
98.
Heng-You Lan 《Journal of Mathematical Analysis and Applications》2007,327(1):481-493
In this paper, we introduce and study a new system of nonlinear A-monotone multivalued variational inclusions in Hilbert spaces. By using the concept and properties of A-monotone mappings, and the resolvent operator technique associated with A-monotone mappings due to Verma, we construct a new iterative algorithm for solving this system of nonlinear multivalued variational inclusions associated with A-monotone mappings in Hilbert spaces. We also prove the existence of solutions for the nonlinear multivalued variational inclusions and the convergence of iterative sequences generated by the algorithm. Our results improve and generalize many known corresponding results. 相似文献
99.
The subject of spectral distribution methods where one derives and applies the locally smoothed forms of observables in nuclei
is briefly reviewed. It is well understood that the local forms (with respect to energy) of the level density function, expectation
values and strength densities are Gaussian, linear (or ratio of Gaussians) and a bivariate Gaussian respectively. To accomodate
symmetries in the above forms, one has to deal with multivariate distributions in general; for example the angular-momentum
(J) decomposition leads to a bivariate Gaussian form for the level density. These results extend to indefinitely large spaces
by method of partitioning and they generate convolution forms. The origin of these remarkable spectral properties is discussed
and shell model examples are given to substantiate their applicability to nuclear systems. Spectral distribution theory is
a practical, usable theory because the smoothed forms are defined in terms of traces of low particle-rank operators, and the
trace information propagates. Finally we discuss the application of the spectral methods for a wide range of nuclear problems;
these include binding energies, orbit occupancies, electromagnetic andβ-decay sum rule quantities, analysis of operators, symmetry breaking, numerical level densities, and determination of bounds
on time-reversal non-invariant part of nucleon-nucleon interaction. 相似文献
100.
设T是m-增生算子,I是恒等映射.本文通过一个反例说明(T+λI)-1(λ>0)不一定是非扩张映射. 相似文献