全文获取类型
收费全文 | 1922篇 |
免费 | 71篇 |
国内免费 | 8篇 |
专业分类
化学 | 1387篇 |
晶体学 | 19篇 |
力学 | 74篇 |
数学 | 290篇 |
物理学 | 231篇 |
出版年
2023年 | 19篇 |
2022年 | 37篇 |
2021年 | 42篇 |
2020年 | 55篇 |
2019年 | 40篇 |
2018年 | 31篇 |
2017年 | 25篇 |
2016年 | 55篇 |
2015年 | 49篇 |
2014年 | 68篇 |
2013年 | 118篇 |
2012年 | 127篇 |
2011年 | 169篇 |
2010年 | 74篇 |
2009年 | 77篇 |
2008年 | 132篇 |
2007年 | 130篇 |
2006年 | 106篇 |
2005年 | 109篇 |
2004年 | 93篇 |
2003年 | 95篇 |
2002年 | 103篇 |
2001年 | 21篇 |
2000年 | 16篇 |
1999年 | 21篇 |
1998年 | 25篇 |
1997年 | 26篇 |
1996年 | 21篇 |
1995年 | 14篇 |
1994年 | 12篇 |
1993年 | 10篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1989年 | 9篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 9篇 |
1984年 | 5篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1974年 | 2篇 |
1895年 | 1篇 |
1887年 | 2篇 |
排序方式: 共有2001条查询结果,搜索用时 15 毫秒
31.
We consider global solutions of the nonlinear Schrödinger equation
相似文献
32.
Thierry de la Rue 《Bulletin of the Brazilian Mathematical Society》2006,37(4):503-521
V.A. Rohlin asked in 1949 whether 2-fold mixing implies 3-fold mixing for a stationary process (ξi )i2ℤ, and the question remains open today. In 1978, F. Ledrappier exhibited a counterexample to the 2-fold mixing implies 3-fold
mixing problem, the socalled 3-dot system, but in the context of stationary random fields indexed by ℤ2.
In this work, we first present an attempt to adapt Ledrappier's construction to the onedimensional case, which finally leads
to a stationary process which is 2-fold but not 3-fold mixing conditionally to the σ-algebra generated by some factor process. Then, using arguments coming from the theory of joinings, we will give some strong obstacles proving that Ledrappier's counterexample
can not be fully adapted to one-dimensional stationary processes. 相似文献
33.
Thierry Lévy 《Bulletin des Sciences Mathématiques》2011,135(6-7):629-649
We discuss an analogy between topological quantum field theories and the theory of Markov processes, which both rely on the combination of a notion of transition and a notion of locality. We assume no prior knowledge of topological quantum field theory (TQFT) and devote the first section to a motivation of its definition, which was originally given by M. Atiyah. We then discuss 1- and 2-dimensional TQFT?s, and a mild generalization of them which incorporates a notion of time and is suited to the parallel with Markov processes.This text is a written version of a talk whose emphasis was on explaining and illustrating ideas. There are few rigorous statements in it, and no proof. 相似文献
34.
This work concerns constructive aspects of measure theory. By considering metric completions of Boolean algebras – an approach
first suggested by Kolmogorov – one can give a very simple construction of e.g. the Lebesgue measure on the unit interval.
The integration spaces of Bishop and Cheng turn out to give examples of such Boolean algebras. We analyse next the notion
of Borel subsets. We show that the algebra of such subsets can be characterised in a pointfree and constructive way by an
initiality condition. We then use our work to define in a purely inductive way the measure of Borel subsets.
Received: 9 November 2000 / Revised version: 23 March 2001 / Published online: 12 July 2002 相似文献
35.
Thierry Moreno 《Journal of synchrotron radiation》2015,22(5):1163-1169
Synchrotron infrared beamlines are powerful tools on which to perform spectroscopy on microscopic length scales but require working with large bending‐magnet source apertures in order to provide intense photon beams to the experiments. Many infrared beamlines use a single toroidal‐shaped mirror to focus the source emission which generates, for large apertures, beams with significant geometrical aberrations resulting from the shape of the source and the beamline optics. In this paper, an optical layout optimized for synchrotron infrared beamlines, that removes almost totally the geometrical aberrations of the source, is presented and analyzed. This layout is already operational on the IR beamline of the Brazilian synchrotron. An infrared beamline design based on a SOLEIL bending‐magnet source is given as an example, which could be useful for future IR beamline improvements at this facility. 相似文献
36.
Thierry Barbot Francesco Bonsante Jean-Marc Schlenker 《Communications in Mathematical Physics》2014,327(3):691-735
We investigate globally hyperbolic 3-dimensional AdS manifolds containing “particles”, i.e., cone singularities of angles less than 2π along a time-like graph Γ. To each such space (equipped with a time-like vector field satisfying some additional properties) we associate a graph and a finite family of pairs of hyperbolic surfaces with cone singularities. We show that this data is sufficient to recover the space locally (i.e., in the neighborhood of a fixed metric). This is a partial extension of a result of Mess for non-singular globally hyperbolic AdS manifolds. 相似文献
37.
38.
We study the quantum nonlinear response to an applied electric field E of a one-dimensional pinned charge-density wave or Luttinger liquid in the presence of disorder. From an explicit construction of low-lying metastable states and of bounce instanton solutions between them, we demonstrate quantum creep v=e(-c/E(1/2)) as well as a sharp crossover at E=E(*) towards a linear response form consistent with variable-range hopping arguments, but dependent only on electronic degrees of freedom. 相似文献
39.
We develop and implement linear formulations of general Nth order stochastic dominance criteria for discrete probability distributions. Our approach is based on a piece-wise polynomial representation of utility and its derivatives and can be implemented by solving a relatively small system of linear inequalities. This approach allows for comparing a given prospect with a discrete set of alternative prospects as well as for comparison with a polyhedral set of linear combinations of prospects. We also derive a linear dual formulation in terms of lower partial moments and co-lower partial moments. An empirical application to historical stock market data suggests that the passive stock market portfolio is highly inefficient relative to actively managed portfolios for all investment horizons and for nearly all investors. The results also illustrate that the mean–variance rule and second-order stochastic dominance rule may not detect market portfolio inefficiency because of non-trivial violations of non-satiation and prudence. 相似文献
40.
Thierry Combot 《Regular and Chaotic Dynamics》2017,22(4):386-407
We consider a lattice ? ? ? n and a trigonometric potential V with frequencies k ∈ ?. We then prove a strong rational integrability condition on V, using the support of its Fourier transform. We then use this condition to prove that a real trigonometric polynomial potential is rationally integrable if and only if it separates up to rotation of the coordinates. Removing the real condition, we also make a classification of rationally integrable potentials in dimensions 2 and 3 and recover several integrable cases. After a complex change of variables, these potentials become real and correspond to generalized Toda integrable potentials. Moreover, along the proof, some of them with high-degree first integrals are explicitly integrated. 相似文献
|