全文获取类型
收费全文 | 176792篇 |
免费 | 862篇 |
国内免费 | 522篇 |
专业分类
化学 | 60873篇 |
晶体学 | 2114篇 |
力学 | 12918篇 |
综合类 | 3篇 |
数学 | 53175篇 |
物理学 | 49093篇 |
出版年
2023年 | 104篇 |
2022年 | 558篇 |
2021年 | 534篇 |
2020年 | 399篇 |
2019年 | 489篇 |
2018年 | 17978篇 |
2017年 | 18583篇 |
2016年 | 9637篇 |
2015年 | 2081篇 |
2014年 | 1020篇 |
2013年 | 1549篇 |
2012年 | 8266篇 |
2011年 | 22006篇 |
2010年 | 12557篇 |
2009年 | 12929篇 |
2008年 | 16914篇 |
2007年 | 22278篇 |
2006年 | 732篇 |
2005年 | 8846篇 |
2004年 | 5199篇 |
2003年 | 5549篇 |
2002年 | 2564篇 |
2001年 | 486篇 |
2000年 | 665篇 |
1999年 | 255篇 |
1998年 | 275篇 |
1997年 | 212篇 |
1996年 | 368篇 |
1995年 | 234篇 |
1994年 | 195篇 |
1993年 | 184篇 |
1992年 | 152篇 |
1991年 | 163篇 |
1990年 | 146篇 |
1989年 | 165篇 |
1988年 | 178篇 |
1987年 | 173篇 |
1986年 | 158篇 |
1985年 | 173篇 |
1984年 | 177篇 |
1983年 | 156篇 |
1982年 | 160篇 |
1981年 | 149篇 |
1980年 | 160篇 |
1979年 | 165篇 |
1978年 | 168篇 |
1976年 | 95篇 |
1973年 | 121篇 |
1969年 | 86篇 |
1968年 | 117篇 |
排序方式: 共有10000条查询结果,搜索用时 98 毫秒
81.
Yasuyuki Kawahigashi 《Communications in Mathematical Physics》2002,226(2):269-287
We study the recent construction of subfactors by Rehren which generalizes the Longo–Rehren subfactors. We prove that if
we apply this construction to a non-degenerately braided subfactor N⊂M and α±-induction, then the resulting subfactor is dual to the Longo–Rehren subfactor M⊗M
opp⊂R arising from the entire system of irreducible endomorphisms of M resulting from αplusmn;-induction. As a corollary, we solve a problem on existence of braiding raised by Rehren negatively. Furthermore, we generalize
our previous study with Longo and Müger on multi-interval subfactors arising from a completely rational conformal net of factors
on S
1 to a net of subfactors and show that the (generalized) Longo–Rehren subfactors and α-induction naturally appear in this context.
Received: 11 September 2001 / Accepted: 7 October 2001 相似文献
82.
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
83.
84.
85.
Annegret K. Wagler 《Mathematical Methods of Operations Research》2002,56(1):127-149
An edge e of a perfect graph G is critical if G−e is imperfect. We would like to decide whether G−e is still “almost perfect” or already “very imperfect”. Via relaxations of the stable set polytope of a graph, we define two
superclasses of perfect graphs: rank-perfect and weakly rank-perfect graphs. Membership in those two classes indicates how
far an imperfect graph is away from being perfect. We study the cases, when a critical edge is removed from the line graph
of a bipartite graph or from the complement of such a graph. 相似文献
86.
Possible Loss and Recovery of Gibbsianness¶During the Stochastic Evolution of Gibbs Measures 总被引:1,自引:1,他引:0
A.C.D. van Enter R. Fernández F. den Hollander F. Redig 《Communications in Mathematical Physics》2002,226(1):101-130
We consider Ising-spin systems starting from an initial Gibbs measure ν and evolving under a spin-flip dynamics towards a
reversible Gibbs measure μ≠ν. Both ν and μ are assumed to have a translation-invariant finite-range interaction. We study
the Gibbsian character of the measure νS(t) at time t and show the following:
(1) For all ν and μ, νS(t) is Gibbs for small t.
(2) If both ν and μ have a high or infinite temperature, then νS(t) is Gibbs for all t > 0.
(3) If ν has a low non-zero temperature and a zero magnetic field and μ has a high or infinite temperature, then νS(t) is Gibbs for small t and non-Gibbs for large t.
(4) If ν has a low non-zero temperature and a non-zero magnetic field and μ has a high or infinite temperature, then νS(t) is Gibbs for small t, non-Gibbs for intermediate t, and Gibbs for large t.
The regime where μ has a low or zero temperature and t is not small remains open. This regime presumably allows for many different scenarios.
Received: 26 April 2001 / Accepted: 10 October 2001 相似文献
87.
Alexander Krasnosel'skii Dmitrii Rachinskii 《NoDEA : Nonlinear Differential Equations and Applications》2002,9(1):93-115
We consider autonomous systems with a nonlinear part depending on a parameter and study Hopf bifurcations at infinity. The
nonlinear part consists of the nonlinear functional term and the Prandtl--Ishlinskii hysteresis term. The linear part of the
system has a special form such that the close-loop system can be considered as a hysteresis perturbation of a quasilinear
Hamiltonian system. The Hamiltonian system has a continuum of arbitrarily large cycles for each value of the parameter. We
present sufficient conditions for the existence of bifurcation points for the non-Hamiltonian system with hysteresis. These
bifurcation points are determined by simple characteristics of the hysteresis nonlinearity. 相似文献
88.
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
89.
Robert M. O'Keefe 《The Journal of the Operational Research Society》1989,40(5):415-422
Cognitive style refers to differences that can be perceived in individuals due to differing cognitive structures. There has been a large amount of research on how cognitive style affects managerial decision-making, particularly in the context of management information systems, but little or no attempt to relate these findings to operational research. This paper reviews the findings of cognitive-style research from the perspective of operational research, and draws a number of useful inferences concerning the matching of OR aids to managers, the presentation of information and recommendations, the use and acceptance of OR, and the structure of OR groups. Further, it is argued that cognitive-style findings help to give a justification to the move towards ‘soft’ approaches to analysis. 相似文献
90.
William F. Bowlin 《The Journal of the Operational Research Society》1987,38(2):127-135
The objective of this research is to evaluate a new methodology, data envelopment analysis (DEA), as a tool for measuring and evaluating the operational efficiency of US Air Force organizations. This study involves the application of DEA to locate possible inefficiencies in the performance of US Air Force real-property maintenance activities. Dynamic behaviour, as exhibited via window analyses, is reviewed along with static counterparts. The testing was done in close coordination with Air Force officials, who reviewed the results for accuracy, validity and relevance. We conclude that this type of efficiency analysis does have value for the Air Force, where it can serve as a guide to auditors, budget programmers, managers and others in measuring, evaluating and enhancing operational efficiency. 相似文献