全文获取类型
收费全文 | 5329篇 |
免费 | 338篇 |
国内免费 | 385篇 |
专业分类
化学 | 170篇 |
晶体学 | 3篇 |
力学 | 314篇 |
综合类 | 64篇 |
数学 | 4635篇 |
物理学 | 866篇 |
出版年
2024年 | 9篇 |
2023年 | 68篇 |
2022年 | 68篇 |
2021年 | 86篇 |
2020年 | 131篇 |
2019年 | 146篇 |
2018年 | 115篇 |
2017年 | 114篇 |
2016年 | 111篇 |
2015年 | 116篇 |
2014年 | 278篇 |
2013年 | 489篇 |
2012年 | 254篇 |
2011年 | 311篇 |
2010年 | 285篇 |
2009年 | 429篇 |
2008年 | 417篇 |
2007年 | 390篇 |
2006年 | 289篇 |
2005年 | 229篇 |
2004年 | 215篇 |
2003年 | 225篇 |
2002年 | 180篇 |
2001年 | 135篇 |
2000年 | 128篇 |
1999年 | 139篇 |
1998年 | 113篇 |
1997年 | 125篇 |
1996年 | 100篇 |
1995年 | 62篇 |
1994年 | 71篇 |
1993年 | 36篇 |
1992年 | 30篇 |
1991年 | 24篇 |
1990年 | 15篇 |
1989年 | 12篇 |
1988年 | 12篇 |
1987年 | 7篇 |
1986年 | 11篇 |
1985年 | 19篇 |
1984年 | 4篇 |
1983年 | 7篇 |
1982年 | 5篇 |
1981年 | 7篇 |
1980年 | 12篇 |
1978年 | 4篇 |
1977年 | 7篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1973年 | 3篇 |
排序方式: 共有6052条查询结果,搜索用时 93 毫秒
101.
Jun Hu Zhong-Ci Shi 《计算数学(英文版)》2006,24(1):1-8
We consider the quadrilateral Q1 isoparametric element and establish an optimal error estimate in H^1 norm for the interpolation operator under a weaker mesh condition which admits anisotropic quadrilaterals and allows the quadrilateral to become a regular triangle in the sense of maximum angle condition [5, 11]. 相似文献
102.
关于一类空间齐次推广的耗散碰撞Boltzmann方程Cauchy问题 ,对于一般的初始条件得到了正古典解的存在唯一性 . 相似文献
103.
Nest代数上的在零点广义可导映射 总被引:4,自引:0,他引:4
设A为B(H)的子代数, 是A到B(H)的线性映射,我们说 在0点广义可导(广义双边可导),如果对任意的S,T∈A且ST=0(ST=0或TS=0),有 (ST)= (S)T+S (T)-S (I)T.本文主要得到如下结果:(1)有限Nest代数上的每个范数拓扑连续的在0点广义可导的线性映射是广义内导子;(2)若N是完备Nest且H_ H,则algN上的每个范数拓扑连续的在0点广义双边可导的线性映射是广义内导子. 相似文献
104.
Let D be a simply laced Dynkin diagram of rank r whose affinization has the shape of a star (i.e., D4,E6,E7,E8). To such a diagram one can attach a group G whose generators correspond to the legs of the affinization, have orders equal to the leg lengths plus 1, and the product of the generators is 1. The group G is then a 2-dimensional crystallographic group: G=Z??Z2, where ? is 2, 3, 4, and 6, respectively. In this paper, we define a flat deformation H(t,q) of the group algebra C[G] of this group, by replacing the relations saying that the generators have prescribed orders by their deformations, saying that the generators satisfy monic polynomial equations of these orders with arbitrary roots (which are deformation parameters). The algebra H(t,q) for D4 is the Cherednik algebra of type C∨C1, which was studied by Noumi, Sahi, and Stokman, and controls Askey-Wilson polynomials. We prove that H(t,q) is the universal deformation of the twisted group algebra of G, and that this deformation is compatible with certain filtrations on C[G]. We also show that if q is a root of unity, then for generic t the algebra H(t,q) is an Azumaya algebra, and its center is the function algebra on an affine del Pezzo surface. For generic q, the spherical subalgebra eH(t,q)e provides a quantization of such surfaces. We also discuss connections of H(t,q) with preprojective algebras and Painlevé VI. 相似文献
105.
E.H. El Abdalaoui F. Parreau A.A. Prikhod'ko 《Annales de l'Institut Henri Poincaré (B) Probabilités et Statistiques》2006,42(6):671-681
It is shown that for any family of probability measures in Ornstein type constructions, the corresponding transformation has almost surely a singular spectrum. This is a new generalization of Bourgain's theorem [J. Bourgain, On the spectral type of Ornstein class one transformations, Israel J. Math. 84 (1993) 53–63], same result is proved for Rudolph's construction [D. Rudolph, An example of a measure-preserving map with minimal self-joining and applications, J. Anal. Math. 35 (1979) 97–122]. 相似文献
106.
Li CHEN Hui Zhao LIU 《数学学报(英文版)》2006,22(2):455-468
The existence and uniqueness of the generalized solution for a kind of nonparametric curvature flow problem are obtained. This kind of curvature flow problem describes the evolution of graphs with speed depending on the reciprocal of the Gauss curvature. 相似文献
107.
采用旋转锥镜相机,进行激光散斑剪切照相,研测缓慢变形物体的动态曲率和斜率。拍摄一张散斑图即可获得曲率和斜率动态变化的全过程。 相似文献
108.
《Expositiones Mathematicae》2022,40(4):894-909
It is well-known that differentiation of hypergeometric function multiplied by a certain power function yields another hypergeometric function with a different set of parameters. Such differentiation identities for hypergeometric functions have been used widely in various fields of applied mathematics and natural sciences. In this expository note, we provide a simple proof of the differentiation identities, which is based only on the definition of the coefficients for the power series expansion of the hypergeometric functions. 相似文献
109.
《Operations Research Letters》2022,50(1):1-7
Fisher linear discriminant analysis is a well-known technique for dimensionality reduction and classification. The method was first formulated in 1936 by Fisher. In this paper we concentrate on three different formulations of the multi-dimensional problem. We provide a mathematical explanation why two of the formulations are equivalent and prove that this equivalency can be extended to a broader class of objective functions. The second contribution is a rate of convergence of a fixed point method for solving the third model. 相似文献
110.
The authors study rotational hypersurfaces with constant Gauss-Kronecker curvature in Rn. They solve the ODE associated with the generating curve of such hypersurface using integral expressions and obtain several geometric properties of such hypersurfaces. In particular, they discover a class of non-compact rotational hypersurfaces with constant and negative Gauss-Kronecker curvature and finite volume, which can be seen as the higher-dimensional generalization of the pseudo-sphere. 相似文献