全文获取类型
收费全文 | 5690篇 |
免费 | 141篇 |
国内免费 | 39篇 |
专业分类
化学 | 236篇 |
晶体学 | 22篇 |
力学 | 57篇 |
综合类 | 6篇 |
数学 | 5119篇 |
物理学 | 430篇 |
出版年
2023年 | 6篇 |
2022年 | 4篇 |
2021年 | 14篇 |
2020年 | 35篇 |
2019年 | 168篇 |
2018年 | 190篇 |
2017年 | 94篇 |
2016年 | 59篇 |
2015年 | 71篇 |
2014年 | 183篇 |
2013年 | 314篇 |
2012年 | 229篇 |
2011年 | 346篇 |
2010年 | 352篇 |
2009年 | 487篇 |
2008年 | 456篇 |
2007年 | 445篇 |
2006年 | 335篇 |
2005年 | 203篇 |
2004年 | 179篇 |
2003年 | 180篇 |
2002年 | 124篇 |
2001年 | 122篇 |
2000年 | 119篇 |
1999年 | 134篇 |
1998年 | 118篇 |
1997年 | 78篇 |
1996年 | 113篇 |
1995年 | 118篇 |
1994年 | 121篇 |
1993年 | 103篇 |
1992年 | 58篇 |
1991年 | 28篇 |
1990年 | 16篇 |
1989年 | 22篇 |
1988年 | 24篇 |
1987年 | 17篇 |
1986年 | 14篇 |
1985年 | 20篇 |
1984年 | 31篇 |
1983年 | 19篇 |
1982年 | 22篇 |
1981年 | 18篇 |
1980年 | 9篇 |
1979年 | 17篇 |
1978年 | 18篇 |
1977年 | 12篇 |
1976年 | 6篇 |
1975年 | 8篇 |
1974年 | 6篇 |
排序方式: 共有5870条查询结果,搜索用时 31 毫秒
1.
Liang Zhao 《Journal of Differential Equations》2019,266(9):5615-5624
In this paper, let be n-dimensional noncompact metric measure space which satisfies Poincaré inequality with some Ricci curvature condition. We obtain a Liouville theorem for positive weak solutions to weighted p-Lichnerowicz equation where are real constants. 相似文献
2.
3.
Sameerah Jamal 《Journal of Differential Equations》2019,266(7):4018-4026
A manifold that contains small perturbations will induce a perturbed partial differential equation. The partial differential equation that we select is the Poisson equation – in order to explore the interplay between the geometry of the manifold and the perturbations. Specifically, we show how the problem of symmetry determination, for higher-order perturbations, can be elegantly expressed via geometric conditions. 相似文献
4.
Peter Imkeller 《Probability Theory and Related Fields》1996,106(1):105-135
Summary. The analytic treatment of problems related to the asymptotic behaviour of random dynamical systems generated by stochastic
differential equations suffers from the presence of non-adapted random invariant measures. Semimartingale theory becomes accessible
if the underlying Wiener filtration is enlarged by the information carried by the orthogonal projectors on the Oseledets spaces
of the (linearized) system.
We study the corresponding problem of preservation of the semimartingale property and the validity of a priori inequalities
between the norms of stochastic integrals in the enlarged filtration and norms of their quadratic variations in case the random
element F enlarging the filtration is real valued and possesses an absolutely continuous law. Applying the tools of Malliavin’s calculus,
we give smoothness conditions on F under which the semimartingale property is preserved and a priori martingale inequalities are valid.
Received: 12 April 1995 / In revised form: 7 March 1996 相似文献
5.
M. Brokate D. Rachinskii 《NoDEA : Nonlinear Differential Equations and Applications》2006,13(4):385-411
The paper is concerned with the study of plasticity models described by differential equations with stop and play operators.
We suggest sufficient conditions for the global stability of a unique periodic solution for the scalar models and for the
vector models with biaxial inputs of a particular form, namely the sum of a uniaxial function and a constant term. For another
class of simple biaxial inputs, we present an example of the existence of unstable periodic solutions.
The paper was written during the research stay of D. Rachinskii at the Technical University Munich supported by the research
fellowship from the Alexander von Humboldt Foundation. His work was partially supported by the Russian Science Support Foundation, Russian Foundation for Basic Research (Grant No. 01-01-00146, 03-01-00258), and the Grants of the President of Russia (Grant No. MD-87.2003.01, NS-1532.2003.1). The support is gratefully acknowledged. 相似文献
6.
We consider normal ≡ Gaussian seemingly unrelated regressions (SUR) with incomplete data (ID). Imposing a natural minimal set of conditional independence constraints, we find a restricted SUR/ID model whose likelihood function and parameter space factor into the product of the likelihood functions and the parameter spaces of standard complete data multivariate analysis of variance models. Hence, the restricted model has a unimodal likelihood and permits explicit likelihood inference. In the development of our methodology, we review and extend existing results for complete data SUR models and the multivariate ID problem. 相似文献
7.
Balázs Szendröi 《Mathematische Zeitschrift》2002,240(2):233-241
This note shows that a certain toric quotient of the quintic Calabi-Yau threefold in provides a counterexample to a recent conjecture of Cox and Katz concerning nef cones of toric hypersurfaces.
Received: 8 February 2001; in final form: 17 September 2001 / Published online: 1 February 2002 相似文献
8.
9.
Franz-Viktor Kuhlmann 《Advances in Mathematics》2004,188(2):399-424
We consider the Zariski space of all places of an algebraic function field F|K of arbitrary characteristic and investigate its structure by means of its patch topology. We show that certain sets of places with nice properties (e.g., prime divisors, places of maximal rank, zero-dimensional discrete places) lie dense in this topology. Further, we give several equivalent characterizations of fields that are large, in the sense of F. Pop's Annals paper Embedding problems over large fields. We also study the question whether a field K is existentially closed in an extension field L if L admits a K-rational place. In the appendix, we prove the fact that the Zariski space with the Zariski topology is quasi-compact and that it is a spectral space. 相似文献
10.
Paulo D. Cordaro 《Advances in Mathematics》2004,184(1):89-118
Taking as a start point the recent article of Meziani [7], we present several results concerning the normalization of a class of complex vector fields in the plane which degenerate along a real curve. We mainly deal with operators with finite regularity and analyze both the local situation as well as the case of normalization near a circle. Some related questions (e.g., on semi-global solvability and on the normalization of a class of generalized Mizohata operators) are also discussed. 相似文献