全文获取类型
收费全文 | 395181篇 |
免费 | 3067篇 |
国内免费 | 1251篇 |
专业分类
化学 | 178438篇 |
晶体学 | 5468篇 |
力学 | 21501篇 |
综合类 | 2篇 |
数学 | 76249篇 |
物理学 | 117841篇 |
出版年
2020年 | 1795篇 |
2019年 | 2072篇 |
2018年 | 18885篇 |
2017年 | 19434篇 |
2016年 | 12383篇 |
2015年 | 4104篇 |
2014年 | 4289篇 |
2013年 | 11596篇 |
2012年 | 14897篇 |
2011年 | 29500篇 |
2010年 | 17584篇 |
2009年 | 17925篇 |
2008年 | 23936篇 |
2007年 | 28922篇 |
2006年 | 8758篇 |
2005年 | 15537篇 |
2004年 | 11559篇 |
2003年 | 11055篇 |
2002年 | 8310篇 |
2001年 | 7555篇 |
2000年 | 5886篇 |
1999年 | 4366篇 |
1998年 | 3744篇 |
1997年 | 3706篇 |
1996年 | 3580篇 |
1995年 | 3319篇 |
1994年 | 3091篇 |
1993年 | 3149篇 |
1992年 | 3406篇 |
1991年 | 3455篇 |
1990年 | 3253篇 |
1989年 | 3218篇 |
1988年 | 3293篇 |
1987年 | 3158篇 |
1986年 | 3046篇 |
1985年 | 4108篇 |
1984年 | 4277篇 |
1983年 | 3519篇 |
1982年 | 3864篇 |
1981年 | 3754篇 |
1980年 | 3636篇 |
1979年 | 3681篇 |
1978年 | 3916篇 |
1977年 | 3649篇 |
1976年 | 3874篇 |
1975年 | 3446篇 |
1974年 | 3564篇 |
1973年 | 3914篇 |
1972年 | 2378篇 |
1971年 | 1816篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Yu. K. Dem’yanovich 《Journal of Mathematical Sciences》2007,144(6):4548-4567
On a sequence of embedded nonuniform grids, chains of embedded spaces of minimal splines (not necessarily polynomial) are
constructed. The wavelet decomposition is given. The basis wavelets are compactly supported and admit simple analytic representation.
The corresponding decomposition and reconstruction formulas are derived. The variety of spaces under consideration is identified
with the variety of complete sequences of points of the direct product of an interval and a projective plane. Bibliography:
20 titles.
__________
Translated from Problemy Matematicheskogo Analiza, No. 35, 2007, pp. 15–31 相似文献
992.
993.
A base of the universal multiplicative envelope of the free Malcev superalgebra ℳ on one odd generator is constructed. Some
corollaries for skew-symmetric functions and central elements in free Malcev and free alternative algebras are obtained. Moreover,
a base of the Poisson-Malcev superalgebra of ℳ is constructed. As a corollary, a set of elements that spans the free alternative
superalgebra on one odd generator is obtained.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 10, No. 4, pp. 97–106, 2004. 相似文献
994.
Guang-hua DONG~ Yan-pei LIU Department of Mathematics School of Science Beijing Jiaotong University Beijing China 《中国科学A辑(英文版)》2007,50(11):1563-1570
In this paper,we provide a new class of up-embeddable graphs,and obtain a tight lower bound on the maximum genus of a class of 2-connected pseudographs of diameter 2 and of a class of diameter 4 multi-graphs.This extends a result of Skoviera. 相似文献
995.
Yakov Varshavsky 《Geometric And Functional Analysis》2007,17(1):271-319
The goal of this paper is to generalize a theorem of Fujiwara (Deligne’s conjecture) to the situation appearing in a joint
work [KV] with David Kazhdan on the global Langlands correspondence over function fields. Moreover, our proof is more elementary
than the original one and stays in the realm of ordinary algebraic geometry, that is, does not use rigid geometry. We also
give a proof of the Lefschetz–Verdier trace formula and of the additivity of filtered trace maps, thus making the paper essentially
self-contained.
The work was supported by the Israel Science Foundation (Grant No. 555/04)
Received: May 2005 Accepted: August 2005 相似文献
996.
997.
It is demonstrated theoretically that the initial (both elastic and viscous) magnetic susceptibility components for nanocrystalline
magnets caused by the processes of rotations (in the region of linear response) have resonant rather than relaxation character
typical already for the susceptibility component caused by displacements of domain boundaries.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 88–92, June, 2007. 相似文献
998.
Ji-hong SU & Yi-cai ZHAO LMAM Department of Mathematics Jinan University Guangzhou China 《中国科学A辑(英文版)》2007,50(4):495-502
Let X be a smooth projective variety of dimension 2k-1 (k≥3) over the complex number field. Assume that fR: X→Y is a small contraction such that every irreducible component Ei of the exceptional locus of fR is a smooth subvariety of dimension k. It is shown that each Ei is isomorphic to the k-dimensional projective space Pk, the k-dimensional hyperquadric surface Qk in Pk 1, or a linear Pk-1-bundle over a smooth curve. 相似文献
999.
1000.
René Meziat Diego Patiño Pablo Pedregal 《Computational Optimization and Applications》2007,38(1):147-171
We propose an alternative method for computing effectively the solution of non-linear, fixed-terminal-time, optimal control
problems when they are given in Lagrange, Bolza or Mayer forms. This method works well when the nonlinearities in the control
variable can be expressed as polynomials. The essential of this proposal is the transformation of a non-linear, non-convex
optimal control problem into an equivalent optimal control problem with linear and convex structure. The method is based on
global optimization of polynomials by the method of moments. With this method we can determine either the existence or lacking
of minimizers. In addition, we can calculate generalized solutions when the original problem lacks of minimizers. We also
present the numerical schemes to solve several examples arising in science and technology. 相似文献