全文获取类型
收费全文 | 9443篇 |
免费 | 884篇 |
国内免费 | 1198篇 |
专业分类
化学 | 107篇 |
力学 | 395篇 |
综合类 | 204篇 |
数学 | 9345篇 |
物理学 | 1474篇 |
出版年
2024年 | 16篇 |
2023年 | 95篇 |
2022年 | 111篇 |
2021年 | 139篇 |
2020年 | 212篇 |
2019年 | 260篇 |
2018年 | 260篇 |
2017年 | 282篇 |
2016年 | 305篇 |
2015年 | 207篇 |
2014年 | 446篇 |
2013年 | 726篇 |
2012年 | 398篇 |
2011年 | 542篇 |
2010年 | 516篇 |
2009年 | 719篇 |
2008年 | 687篇 |
2007年 | 725篇 |
2006年 | 645篇 |
2005年 | 568篇 |
2004年 | 464篇 |
2003年 | 501篇 |
2002年 | 468篇 |
2001年 | 312篇 |
2000年 | 350篇 |
1999年 | 322篇 |
1998年 | 279篇 |
1997年 | 265篇 |
1996年 | 168篇 |
1995年 | 87篇 |
1994年 | 75篇 |
1993年 | 49篇 |
1992年 | 44篇 |
1991年 | 31篇 |
1990年 | 23篇 |
1989年 | 18篇 |
1988年 | 20篇 |
1987年 | 11篇 |
1986年 | 5篇 |
1985年 | 17篇 |
1984年 | 34篇 |
1983年 | 14篇 |
1982年 | 28篇 |
1981年 | 16篇 |
1980年 | 23篇 |
1979年 | 12篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1936年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
161.
H. Petersson 《Acta Mathematica Hungarica》2003,100(1-2):69-81
The PDE-preserving operators O on the space of nuclearly entire functions of bounded type HNb(E) on a Banach space E are characterized. An operator is PDE-preserving when it preserves homogenous solutions to homogeneous convolution equations.
We establish a one to one correspondence between O and a set Σ of sequences of entire functionals, i.e. exponential type functions. In this way, algebraic structures on Σ,
such as ring structures, can be carried over to O and vice versa. In particular, it follows that O is a non-commutative ring (algebra) with unity with respect to composition and the convolution operators form a commutative
subring (subalgebra). We discuss range and kernel properties, for the operators in O, and characterize the projectors (onto polynomial spaces) in O by determining the corresponding elements in Σ.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
162.
含k-次增生算子的Ishikawa迭代的收敛性问题 总被引:9,自引:0,他引:9
主要研究了非线性方程x Tx=f的Ishikawa迭代解.其中T为k-次增生的或增生的,并在一致光滑和任意的实Banach空间分别研究了上述方程的带误差的Ishikawa迭代解,从而推广了已知的一些结果。 相似文献
163.
Bao Tong Cui Maoan Han Huizhong Yang 《Journal of Computational and Applied Mathematics》2005,180(2):365-375
This paper deals with the oscillation problems of delay hyperbolic systems with impulses. Some sufficient conditions for oscillations of impulsive delay hyperbolic systems with Robin boundary conditions are obtained and the criteria of oscillation of the systems are established. 相似文献
164.
A specific quantum Lax operator, forming a quantum U
q
(sl
n) chain, is suggested. The intertwining R
L
L relation is proved. The invariant local 2+1-dimensional reformulation of the auxiliary linear problem for the L-operator is discussed. 相似文献
165.
In previous work, a probabilistic approach to controlling difficulties of density in hyperbolic space led to a workable notion of optimal density for packings of bodies. In this paper we extend an ergodic theorem of Nevo to provide an appropriate definition of those packings to be considered optimally dense. Examples are given to illustrate various aspects of the density problem, in particular the shift in emphasis from the analysis of individual packings to spaces of packings. 相似文献
166.
Daeyong Kim 《Geometriae Dedicata》2004,106(1):51-78
In this paper, we give analogue of Jörgensen's inequality for nonelementary groups of isometries of complex hyperbolic 2-space generated by two elements, one of which is either loxodromic or boundary elliptic for the same group of isometries of quaternionic hyperbolic 2-space. And we give a sufficient condition for a nonelementary subgroup of isometries of quaternionic hyperbolic 2-space generated by two elements one of which is parabolic not to be discrete. 相似文献
167.
Based on the previously developed technique using the Laplace transformation of distributions with compact support, we calculate the Hochschild cohomologies of the algebra of smooth functions on a finite-dimensional real vector space with coefficients in the adjoint representation. 相似文献
168.
Zhangjian Hu 《Journal of Mathematical Analysis and Applications》2004,296(2):435-454
We define an extended Cesàro operator Tg with holomorphic symbol g in the unit ball B of Cn. For a large class of weights w we characterize those g for which Tg is bounded (or compact) from Bergman space Lpa,w(B) to Lqa,w(B), 0<p,q<∞. In addition, we obtain some results about equivalent norms, the norm of point evaluation functionals, and the interpolation sequences on Lpa,w(B). 相似文献
169.
无界区域R1上推广的B-BBM方程的整体吸引子 总被引:4,自引:0,他引:4
本文研究了无界区域R^1上推广的B—BBM方程的长时间动力学行为,证明了该方程整体吸引子的存在性. 相似文献
170.
We provide a new and short proof for Rockafellar's characterization of maximal monotone operators in reflexive Banach spaces based on S. Fitzpatrick's function and a technique used by R. S. Burachik and B. F. Svaiter for proving their result on the representation of a maximal monotone operator by convex functions.