全文获取类型
收费全文 | 2411篇 |
免费 | 174篇 |
国内免费 | 154篇 |
专业分类
化学 | 185篇 |
晶体学 | 5篇 |
力学 | 265篇 |
综合类 | 28篇 |
数学 | 1599篇 |
物理学 | 657篇 |
出版年
2024年 | 2篇 |
2023年 | 36篇 |
2022年 | 45篇 |
2021年 | 59篇 |
2020年 | 61篇 |
2019年 | 81篇 |
2018年 | 81篇 |
2017年 | 69篇 |
2016年 | 67篇 |
2015年 | 63篇 |
2014年 | 119篇 |
2013年 | 267篇 |
2012年 | 87篇 |
2011年 | 108篇 |
2010年 | 108篇 |
2009年 | 152篇 |
2008年 | 171篇 |
2007年 | 167篇 |
2006年 | 125篇 |
2005年 | 91篇 |
2004年 | 120篇 |
2003年 | 95篇 |
2002年 | 86篇 |
2001年 | 60篇 |
2000年 | 57篇 |
1999年 | 51篇 |
1998年 | 55篇 |
1997年 | 40篇 |
1996年 | 32篇 |
1995年 | 23篇 |
1994年 | 36篇 |
1993年 | 14篇 |
1992年 | 23篇 |
1991年 | 14篇 |
1990年 | 9篇 |
1989年 | 12篇 |
1987年 | 9篇 |
1986年 | 7篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有2739条查询结果,搜索用时 15 毫秒
101.
102.
61. IntroductionLet P be a submanifold of an n-dimensional riemannian manifold AI. Expressions fOrthe kth integrated mean curvatures, M^P(t), (i. e. the integral of tho kth mcan curvature,k = 0, 1,' l n -- l), of a tubular hypersurface P of radius t about P, in terms of theRiemann curvature tensor of P. are calculated when AI is Euclidean or a rank one symmetricspace[5'13"1. Moreover, when P is a closed convex hypersurface of thc n-dimensional spaceof constant curvature A', Santal6 has… 相似文献
103.
We construct the intertwining operator superalgebras and vertex tensor categories for the superconformal unitary minimal models and other related models.
104.
E. Vasserot 《Compositio Mathematica》2002,131(1):51-60
It was proved by Ginzburg, Mirkovic and Vilonen that the G(O)-equivariant perverse sheaves on the affine Grassmannian of a connected reductive group G form a tensor category equivalent to the tensor category of finite dimensional representations of the dual group G
. In this paper we construct explicitly the action of G
on the global cohomology of a perverse sheaf. 相似文献
105.
The spaces of linear differential operators
acting on -densities on
and the space
of functions on
which are polynomial on the fibers are not isomorphic as modules over the Lie algebra Vect (n) of vector fields of n. However, these modules are isomorphic as sl(n + 1,)-modules where
is the Lie algebra of infinitesimal projective transformations. In addition, such an
-equivariant bijection is unique (up to normalization). This leads to a notion of projectively equivariant quantization and symbol calculus for a manifold endowed with a (flat) projective structure. We apply the
-equivariant symbol map to study the
of kth-order linear differential operators acting on -densities, for an arbitrary manifold M and classify the quotient-modules
. 相似文献
106.
107.
JianHuaSUN 《数学学报(英文版)》2005,21(1):65-80
In this paper we study the singularity at the origin with three-fold zero eigenvalue forsymmetric vector fields with nilpotent linear part and 3-jet C^∞-equivalent to y δ/δx zδ/δy ax^2yδ/δz with a≠0. We first obtain several subfamilies of the symmetric versal unfoldings of this singularityby using the normal form and blow-up methods under some conditions, and derive the local and global bifurcation behavior, then prove analytically the existence of the Sil‘nikov homoclinic bifurcation for some subfamilies of the symmetric versal unfoldings of this singularity, by using the generalized Mel‘nikov methods of a homoclinic orbit to a hyperbolic or non-hyperbolic equilibrium in a highdimensional space. 相似文献
108.
Null isotropy in a spacetime is defined. The relation of null isotropy to the constant curvature and infinitesimal spatial
isotropy is investigated. The influence of null isotropy on conjugate points along null geodesics and curvature singularities
is investigated. 相似文献
109.
Recent development brings new results on the interplay of states on operator algebras and axiomatics of quantum mechanics.
Neither hidden space in the sense of Kochen and Specker nor approximate hidden variables exist on von Neumann algebras. Tracial
properties of states are connected with dispersions. The axioms on composite systems simplify to state extension properties. 相似文献
110.
I. Haysak Yu. Fekete V. Morokhovych S. Chalupka M. Salak 《Czechoslovak Journal of Physics》2005,55(5):541-554
Based on the numeric solution of a system of coupled channels for vector mesons (S-and D-waves mixing)and for tensor mesons (P- and F- waves mixing) mass spectrum and wave functions of a family of vector mesons q
in triplet states a e obtained. The calculations are performed using a well-known Cornell potential with a mixed Lorentz- structure of the confinement term. The spin-dependent part of the potential is taken from the Breit-Fermi approach.The effect of irregular terms of the potential is considered within the framework of the perturbation theory and/or of the configuration interaction approach, modified for a system of coupled equations. It is shown that even a small integral contribution of the D-wave to the total wave function of q
system is very impotant for the calculation of certain characteristics of the meson states. 相似文献