全文获取类型
收费全文 | 3523篇 |
免费 | 122篇 |
国内免费 | 26篇 |
专业分类
化学 | 2481篇 |
晶体学 | 19篇 |
力学 | 53篇 |
数学 | 549篇 |
物理学 | 569篇 |
出版年
2024年 | 5篇 |
2023年 | 27篇 |
2022年 | 65篇 |
2021年 | 97篇 |
2020年 | 86篇 |
2019年 | 105篇 |
2018年 | 118篇 |
2017年 | 80篇 |
2016年 | 136篇 |
2015年 | 127篇 |
2014年 | 145篇 |
2013年 | 199篇 |
2012年 | 239篇 |
2011年 | 259篇 |
2010年 | 172篇 |
2009年 | 112篇 |
2008年 | 242篇 |
2007年 | 242篇 |
2006年 | 214篇 |
2005年 | 189篇 |
2004年 | 148篇 |
2003年 | 119篇 |
2002年 | 99篇 |
2001年 | 44篇 |
2000年 | 30篇 |
1999年 | 36篇 |
1998年 | 34篇 |
1997年 | 21篇 |
1996年 | 31篇 |
1995年 | 23篇 |
1994年 | 29篇 |
1993年 | 15篇 |
1992年 | 11篇 |
1991年 | 11篇 |
1989年 | 8篇 |
1988年 | 11篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 9篇 |
1983年 | 9篇 |
1982年 | 10篇 |
1981年 | 6篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1977年 | 5篇 |
1976年 | 12篇 |
1975年 | 11篇 |
1973年 | 7篇 |
1972年 | 4篇 |
1954年 | 5篇 |
排序方式: 共有3671条查询结果,搜索用时 3 毫秒
51.
Nakao?HayashiEmail author Pavel?I.?Naumkin 《Communications in Mathematical Physics》2006,267(2):477-492
We study the final problem for the nonlinear Schrödinger equation where\(\lambda \in{\bf R},n=1,2,3\). If the final data\(u_{+}\in {\bf H}^{0,\alpha }=\left\{ \phi \in {\bf L}^{2}:\left( 1+\left\vert x\right\vert \right) ^{\alpha }\phi \in {\bf L}^{2}\right\} \) with\(\frac{ n}{2} < \alpha < \min \left( n,2,1+\frac{2}{n}\right) \) and the norm\(\Vert \widehat{u_{+}}\Vert _{{\bf L}^{\infty }}\) is sufficiently small, then we prove the existence of the wave operator in L 2. We also construct the modified scattering operator from H 0,α to H 0,δ with\(\frac{n}{2} < \delta < \alpha\).
相似文献
$i{\partial }_{t}u+\frac{1}{2}\Delta u=\lambda|u|^{\frac{2}{n}}u,\quad (t,x)\in {\mathbf{R}}\times \mathbf{R}^{n},$
52.
Maxim A. Gorlach Mingzhao Song Alexey P. Slobozhanyuk Andrey A. Bogdanov Pavel A. Belov 《固体物理学:研究快报》2016,10(12):900-904
Employing nonlocal homogenization approach, we investigate the properties of a metamaterial consisting of parallel metallic wires with dielectric coating. We demonstrate that manipulation of dielectric contrast between wire dielectric shell and host material at fixed frequency results in dynamic switching of metamaterial dispersion regime from elliptic to the hyperbolic one, i.e. the topological transition takes place. It is proved that such transition can be induced by the variation of the metamaterial temperature. Our findings thus pave a way to the implementation of a tunable ‘elliptic‐hyperbolic’ metamaterial. 相似文献
53.
Jan Wild Jiří Macl Hana Šíchová Pavel Boháček Jarmila Prachařová Pavel Kubát Svatopluk Civiš 《Czechoslovak Journal of Physics》1997,47(10):1025-1030
Bi(Pb)–Sr–Ca–Cu–O layers were prepared by laser ablation in air, that is without using a vacuum chamber. At this method a much higher density of pulse energy of laser beam is required (10–30 J cm–2) in comparison with the standard method (1–3 J cm–2). The mentioned condition has specific effects on the nature of the transport of material from the target. As follows from the electron microprobe analysis of the layers, the starting composition of the transported material is identical with that of the superconducting phase sintered in the target; one exception represents Pb, the content of which in the transported material is lower. The image of the process is complemented by UV/VIS spectroscopy scans of the plasma plume. 相似文献
54.
55.
Pavel Dudin Paolo Lacovig Claudio Fava Eugenio Nicolini Anna Bianco Giuseppe Cautero Alexei Barinov 《Journal of synchrotron radiation》2010,17(4):445-450
The extensive upgrade of the experimental end‐station of the SPECTROMICROSCOPY‐3.2L beamline at Elettra synchrotron light source is reported. After the upgrade, angle‐resolved photoemission spectroscopy from a submicrometre spot and scanning microscopy images monitoring the photoelectron signal inside selected acquisition angle and energy windows can be performed. As a test case, angle‐resolved photoemission spectroscopy from single flakes of highly oriented pyrolitic graphite and imaging of the flakes with image contrast owing to rotation of the band dispersion of different flakes are presented. 相似文献
56.
We investigate the properties of the path integral over reparametrizations (or the boundary value of the Liouville field in string theory). Discretizing the path integral, we apply the Metropolis–Hastings algorithm to numerical simulations of a proper (subordinator) stochastic process and find that typical trajectories are not Brownian but rather have discontinuities of the type of Lévy's flights. We study a fractal structure of these trajectories and show that their Hausdorff dimension is zero. We confirm thereby previous results on QCD scattering amplitudes by analytical and numerical calculations. We also perform Monte Carlo simulations of the path integral over reparametrization in the effective string ansatz for a circular Wilson loop and discuss their subtleties associated with the discretization of Douglas' functional. 相似文献
57.
58.
59.