全文获取类型
收费全文 | 2237篇 |
免费 | 70篇 |
国内免费 | 4篇 |
专业分类
化学 | 1458篇 |
晶体学 | 5篇 |
力学 | 112篇 |
数学 | 343篇 |
物理学 | 393篇 |
出版年
2023年 | 20篇 |
2022年 | 47篇 |
2021年 | 69篇 |
2020年 | 40篇 |
2019年 | 43篇 |
2018年 | 37篇 |
2017年 | 32篇 |
2016年 | 73篇 |
2015年 | 66篇 |
2014年 | 64篇 |
2013年 | 108篇 |
2012年 | 129篇 |
2011年 | 164篇 |
2010年 | 66篇 |
2009年 | 67篇 |
2008年 | 131篇 |
2007年 | 125篇 |
2006年 | 120篇 |
2005年 | 95篇 |
2004年 | 76篇 |
2003年 | 65篇 |
2002年 | 90篇 |
2001年 | 31篇 |
2000年 | 23篇 |
1999年 | 28篇 |
1998年 | 21篇 |
1997年 | 27篇 |
1996年 | 54篇 |
1995年 | 31篇 |
1994年 | 19篇 |
1993年 | 32篇 |
1992年 | 17篇 |
1991年 | 12篇 |
1990年 | 15篇 |
1989年 | 18篇 |
1988年 | 17篇 |
1987年 | 20篇 |
1986年 | 11篇 |
1985年 | 13篇 |
1984年 | 12篇 |
1983年 | 9篇 |
1982年 | 9篇 |
1980年 | 9篇 |
1979年 | 13篇 |
1978年 | 19篇 |
1977年 | 14篇 |
1976年 | 15篇 |
1975年 | 7篇 |
1973年 | 7篇 |
1972年 | 10篇 |
排序方式: 共有2311条查询结果,搜索用时 16 毫秒
1.
Marco Biroli Silvia Mataloni Michele Matzeu 《NoDEA : Nonlinear Differential Equations and Applications》2005,12(3):295-321
Some stability results for Mountain Pass and Linking type solutions of semilinear problems involving a very general class
of Dirichlet forms are stated. The non linear terms are supposed to have a suitable superlinear growth and the family of Dirichlet
forms is required to be dominated from below and from above by a fixed diffusion type form. Some concrete examples are also
given. 相似文献
2.
Ultrathin epitaxial Fe films on Cu(1 0 0) with perpendicular magnetization have been used as templates for the preparation of FCC Fe/Cu/Fe trilayers. The magnetic anisotropy and the coupling of these films have been studied by in-situ magneto optical Kerr effect measurements and Kerr microscopy. The magnetic coupling of both Fe layers is found to be dominated by magnetostatic interaction. Adsorbate-induced spin reorientation in the top layer also causes spin reorientation in the bottom layer. The governing role of the Fe-vacuum interface for the magnetism of the whole trilayer is demonstrated. 相似文献
3.
4.
In this paper we give necessary and sufficient conditions for the existence of a C>
0-semigroup in L
1(I) (I real interval) generated by a second-order differential operator when suitable boundary conditions at the endpoints are imposed. 相似文献
5.
We deal with the problem of determining an inclusion within an electrostatic conductor from boundary measurements. Under mild a priori assumptions we establish optimal stability estimates. Measurements are performed on a portion of the boundary of the conductor. 相似文献
6.
7.
Peter Enders 《Optical and Quantum Electronics》1989,21(3):167-181
The small-signal analysis of a simple model of three rate equations is performed rigorously by means of both the Routh-Hurwitz theorem and Descartes' sign rule, and the relationship between bistable behaviour and self-sustained pulsations (SSPs) is investigated. Because one eigenvalue of the Jacobian of the model system is always negative, small-amplitude, sinusoidal SSPs can be described in terms of Haken's dressed-mode variables on a two-dimensional centre manifold. Possible simplifications for the switching modelling are also mentioned. 相似文献
8.
Alberto Caprara Andrea Lodi Silvano Martello Michele Monaci 《Discrete Optimization》2006,3(4):317-326
We address the problem of packing a given set of rectangles into the minimum size square. We consider three versions of the problem, arising when the rectangles (i) are squares; (ii) have a fixed orientation; (iii) can be rotated by 90. For each case we study lower bounds, and analyze their worst-case performance ratio. In addition, we evaluate through computational experiments their average performance on instances from the literature. 相似文献
9.
Nicola Fusco Michele Gori Francesco Maggi 《NoDEA : Nonlinear Differential Equations and Applications》2006,13(4):425-433
An approximation theorem for families of weakly coercive convex functions by means of countably many smooth families of convex
functions is proved. As a consequence, the classical “three-fold” lower semicontinuity theorem for integral functionals of
the Calculus of Variations by James Serrin is unified in one single statement. 相似文献
10.
A path-integral molecular dynamics technique for strongly interacting atoms using ab initio potentials derived from density functional theory is implemented. This allows the efficient inclusion of nuclear quantum dispersion in ab initio simulations at finite temperatures. We present an application to the quantum cluster H
5
+
. 相似文献