全文获取类型
收费全文 | 3161篇 |
免费 | 17篇 |
国内免费 | 13篇 |
专业分类
化学 | 44篇 |
晶体学 | 1篇 |
力学 | 38篇 |
综合类 | 11篇 |
数学 | 3008篇 |
物理学 | 89篇 |
出版年
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 9篇 |
2014年 | 5篇 |
2013年 | 91篇 |
2012年 | 122篇 |
2011年 | 21篇 |
2010年 | 23篇 |
2009年 | 709篇 |
2008年 | 583篇 |
2007年 | 398篇 |
2006年 | 144篇 |
2005年 | 123篇 |
2004年 | 124篇 |
2003年 | 153篇 |
2002年 | 289篇 |
2001年 | 307篇 |
2000年 | 62篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1991年 | 1篇 |
1985年 | 4篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有3191条查询结果,搜索用时 15 毫秒
991.
I. Fonseca G. Leoni R. Paroni 《Calculus of Variations and Partial Differential Equations》2003,17(3):283-309
It is proved that if , with p > 1, if is bounded in , , and if in then provided is 2-quasiconvex and satisfies some appropriate growth and continuity condition. Characterizations of the 2-quasiconvex envelope
when admissible test functions belong to BHp are provided.
Received: 10 October 2001 / Accepted: 8 May 2002 / Published online: 17 December 2002 相似文献
992.
993.
O. Gonzalez J.H. Maddocks F. Schuricht H. von der Mosel 《Calculus of Variations and Partial Differential Equations》2002,14(1):29-68
Many different physical systems, e.g. super-coiled DNA molecules, have been successfully modelled as elastic curves, ribbons
or rods. We will describe all such systems as framed curves, and will consider problems in which a three dimensional framed curve has an associated energy that is to be minimized subject
to the constraint of there being no self-intersection. For closed curves the knot type may therefore be specified a priori.
Depending on the precise form of the energy and imposed boundary conditions, local minima of both open and closed framed curves
often appear to involve regions of self-contact, that is, regions in which points that are distant along the curve are close
in space. While this phenomenon of self-contact is familiar through every day experience with string, rope and wire, the idea
is surprisingly difficult to define in a way that is simultaneously physically reasonable, mathematically precise, and analytically
tractable. Here we use the notion of global radius of curvature of a space curve in a new formulation of the self-contact
constraint, and exploit our formulation to derive existence results for minimizers, in the presence of self-contact, of a
range of elastic energies that define various framed curve models. As a special case we establish the existence of ideal shapes of knots.
Received: 19 January 2001 / Accepted: 23 January 2001 / Published online: 23 April 2001 相似文献
994.
Let R be a discrete nonsingular equivalence relation on a standard probability space , and let V be an ergodic strongly asymptotically central automorphism of R. We prove that every V-invariant cocycle with values in a Polish group G takes values in an abelian subgroup of G.
The hypotheses of this result are satisfied, for example, if A is a finite set, a closed, shift-invariant subset, V is the shift, μ a shift-invariant and ergodic probability measure on X, the two-sided tail-equivalence relation on X, a shift-invariant subrelation which is μ-nonsingular, and a shift-invariant cocycle.
(Received 15 September 2001) 相似文献
995.
An alternative proof of the convergence to self-similar profiles for solutions to the Smoluchowski coagulation equation with
constant coagulation kernel is provided. In contrast to the previous approaches which rely on the Laplace transform, a dynamical
systems approach is used on the equation written in self-similar variables, for which several Liapunov functionals are identified. 相似文献
996.
A subgroup of a finite group G is said to be S-quasinormal in G if it permutes with every Sylow subgroup of G. In this paper we give a characterization of a finite group G under the assumption that every subgroup of the generalized Fitting subgroup of prime order is S-quasinormal in G. 相似文献
997.
We consider local minimizers a domain in , of the variational integral with integrand f of upper (lower) growth rate q (s). We show using a lemma due to Frehse and Seregin that u has H?lder continuous first derivatives provided that .
Received: 2 October 2001 / Accepted: 25 October 2001 / Published online: 28 February 2002 相似文献
998.
Finding Einstein solvmanifolds by a variational method 总被引:2,自引:0,他引:2
Jorge Lauret 《Mathematische Zeitschrift》2002,241(1):83-99
We use a variational approach to prove that any nilpotent Lie algebra having a codimension-one abelian ideal, and anyone
of dimension , admits a rank-one solvable extension which can be endowed with an Einstein left-invariant riemannian metric. A curve of
-dimensional Einstein solvmanifolds is also given.
Received: 29 May 2001; in final form: 4 October 2001 / Published online: 4 April 2002 相似文献
999.
M. Guidorzi 《manuscripta mathematica》2002,107(1):25-41
We prove partial regularity of minimizers of some polyconvex functionals. In particular our results include models such as
∫Ω
a(x,u)(|Du|2+| det Du|2), where a is a bounded H?lder continuous function, such that a(x,u)≥c for some positive constant c.
Received: 2 January 2001 / Revised version: 30 August 2001 相似文献
1000.
Atsushi Noma 《Mathematische Annalen》2002,322(1):69-74
Recall that a projective curve in with ideal sheaf is said to be n-regular if for every integer and that in this case, it is cut out scheme-theoretically by equations of degree at most n. The purpose here is to show that an irreducible, reduced, projective curve of degree d and large arithmetic genus satisfies a smaller regularity bound than the optimal one . For example, if then a curve is -regular unless it is embedded by a complete linear system of degree .
Received: 29 May 2000 / Published online: 24 September 2001 相似文献