全文获取类型
收费全文 | 585841篇 |
免费 | 4944篇 |
国内免费 | 1480篇 |
专业分类
化学 | 274326篇 |
晶体学 | 8428篇 |
力学 | 32882篇 |
综合类 | 3篇 |
数学 | 99923篇 |
物理学 | 176703篇 |
出版年
2021年 | 4529篇 |
2020年 | 5186篇 |
2019年 | 6039篇 |
2018年 | 18191篇 |
2017年 | 17882篇 |
2016年 | 17250篇 |
2015年 | 7276篇 |
2014年 | 11017篇 |
2013年 | 22910篇 |
2012年 | 22124篇 |
2011年 | 31319篇 |
2010年 | 21541篇 |
2009年 | 21762篇 |
2008年 | 26344篇 |
2007年 | 28157篇 |
2006年 | 18691篇 |
2005年 | 17693篇 |
2004年 | 16767篇 |
2003年 | 15683篇 |
2002年 | 14755篇 |
2001年 | 13998篇 |
2000年 | 11079篇 |
1999年 | 8287篇 |
1998年 | 7461篇 |
1997年 | 7218篇 |
1996年 | 6935篇 |
1995年 | 6046篇 |
1994年 | 6039篇 |
1993年 | 6200篇 |
1992年 | 6325篇 |
1991年 | 6698篇 |
1990年 | 6448篇 |
1989年 | 6413篇 |
1988年 | 6141篇 |
1987年 | 6092篇 |
1986年 | 5671篇 |
1985年 | 7226篇 |
1984年 | 7648篇 |
1983年 | 6236篇 |
1982年 | 6709篇 |
1981年 | 6332篇 |
1980年 | 6031篇 |
1979年 | 6470篇 |
1978年 | 6658篇 |
1977年 | 6621篇 |
1976年 | 6778篇 |
1975年 | 6238篇 |
1974年 | 6145篇 |
1973年 | 6346篇 |
1972年 | 4877篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
We obtain upper bounds for the tail distribution of the first nonnegative sum of a random walk and for the moments of the overshoot over an arbitrary nonnegative level if the expectation of jumps is positive and close to zero. In addition, we find an estimate for the expectation of the first ladder epoch. 相似文献
122.
123.
124.
Julio Castellanos 《Mathematische Zeitschrift》2002,239(4):777-802
We consider complete ideals supported on finite sequences of infinitely near points, in regular local rings with dimensions
greater than two. We study properties of factorizations in Lipman special *-simple complete ideals. We relate it to a type
of proximity, linear proximity, of the points, and give conditions in order to have unique factorization. Several examples
are presented.
Received: 2 February 2000 / in final form: 14 March 2001 / Published online: 18 January 2002 相似文献
125.
By using the method of generalized conjugation problems, we propose a numerical scheme for investigation of the redistribution of temperature stresses in a piecewise-homogeneous cylindrical shell caused by a longitudinal crack. This scheme is based on systems of integral equations (some of them are singular) to determine the unknown jumps of integral characteristics of the disturbed temperature field and displacements and their derivatives on the line of a crack and on the interface as well as the derivatives of these integral characteristics with respect to the longitudinal coordinate at the interface. 相似文献
126.
127.
Ricardo Celorrio Vı́ctor Domínguez Francisco-Javier Sayas 《Comptes Rendus Mathematique》2002,334(10):923-926
In this work we study the solution of Laplace's equation in a domain with holes by an iteration consisting of splitting the problem in an exterior one, around the holes, plus an interior problem in the unholed domain. We show the existence of a decomposition of the solution when the exterior problem is represented by means of a single-layer protential. Also, for the three-dimensional case and with some adjustments for the two-dimensional case, we prove convergence of the method by writing the iteration as a Jacobi iteration for an operator equation and studying the spectrum of the iteration operator. To cite this article: R. Celorrio et al., C. R. Acad. Sci. Paris, Ser. I 334 (2002) 923–926. 相似文献
128.
129.
P. Adamson 《Optics & Laser Technology》2002,34(7):561-568
The differential reflection characteristics for ultrathin inhomogeneous dielectric film on absorbing substrate are investigated in the long-wavelength approximation. The obtained first-order expressions for differential reflectivity and changes in the ellipsometric angles caused by ultrathin layer are of immediate interest to the solution of the inverse problem. The method to determine the averaged values (not the realistic profile) of refractive index for inhomogeneous nanometric films are shown. The novel possibilities for determining the dielectric constant and thickness of nanoscale homogeneous films by the differential ellipsometric and reflectivity measurements are developed, and a simple method to estimate whether the nanometric film is homogeneous or not is also discussed. 相似文献
130.
Claudia-Elisabeth Wulz 《Czechoslovak Journal of Physics》2002,52(3):C155-C170
The principal physics goals of the Compact Muon Solenoid experiment under construction at the Large Hadron Collider at CERN in Geneva are reviewed. Procedures to search for the Standard Model Higgs boson, supersymmetric Higgses and other supersymmetric particles are described. 相似文献