全文获取类型
收费全文 | 2231篇 |
免费 | 862篇 |
国内免费 | 387篇 |
专业分类
化学 | 1170篇 |
晶体学 | 39篇 |
力学 | 303篇 |
综合类 | 29篇 |
数学 | 172篇 |
物理学 | 1767篇 |
出版年
2024年 | 12篇 |
2023年 | 48篇 |
2022年 | 97篇 |
2021年 | 100篇 |
2020年 | 108篇 |
2019年 | 114篇 |
2018年 | 69篇 |
2017年 | 104篇 |
2016年 | 163篇 |
2015年 | 118篇 |
2014年 | 174篇 |
2013年 | 195篇 |
2012年 | 182篇 |
2011年 | 184篇 |
2010年 | 155篇 |
2009年 | 166篇 |
2008年 | 183篇 |
2007年 | 176篇 |
2006年 | 156篇 |
2005年 | 132篇 |
2004年 | 128篇 |
2003年 | 120篇 |
2002年 | 94篇 |
2001年 | 80篇 |
2000年 | 62篇 |
1999年 | 61篇 |
1998年 | 44篇 |
1997年 | 34篇 |
1996年 | 36篇 |
1995年 | 33篇 |
1994年 | 25篇 |
1993年 | 19篇 |
1992年 | 16篇 |
1991年 | 17篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 8篇 |
1986年 | 4篇 |
1985年 | 12篇 |
1984年 | 6篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 1篇 |
1976年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1971年 | 5篇 |
排序方式: 共有3480条查询结果,搜索用时 15 毫秒
1.
2.
Matt Visser Carlos Barceló Stefano Liberati 《General Relativity and Gravitation》2002,34(10):1719-1734
Condensed matter systems, such as acoustics in flowing fluids, light in moving dielectrics, or quasiparticles in a moving superfluid, can be used to mimic aspects of general relativity. More precisely these systems (and others) provide experimentally accessible models of curved-space quantum field theory. As such they mimic kinematic aspects of general relativity, though typically they do not mimic the dynamics. Although these analogue models are thereby limited in their ability to duplicate all the effects of Einstein gravity they nevertheless are extremely important—they provide black hole analogues (some of which have already been seen experimentally) and lead to tests of basic principles of curved-space quantum field theory. Currently these tests are still in the realm of gedanken-experiments, but there are plausible candidate models that should lead to laboratory experiments in the not too distant future. 相似文献
3.
固体间界面的物理模型和界面对声波的反射 总被引:4,自引:0,他引:4
简要描述了模拟两固体间界面特性的弹簧模型,该模型最早是根据静力学方法提出的,后来用固体间界面薄层的声波反射方法加以改进,从界面弹簧模型可以方便地得到界面外近似边界条件,其中包含界面“弹簧”振子的劲度常数和质量,文章还给出了两相间固体中界面声反射系数的表达式,介绍了测量界面劲度常数的超声反射谱方法。最后讨论了仍关声波与界面相互作用研究领域中最近的一些研究进展。 相似文献
4.
5.
6.
7.
8.
Zhao Hanzhong 《Acta Mechanica Solida Sinica》2002,15(2):156-162
A finite difference/boundary integral procedure to determine the acoustic reflected pressure from a fluid-loaded bi-laminated
plate is described. The bi-laminate is composed of a piezoelectric layer and an elastic layer in contact with the fluid, and
is held by an acoustically hard baffle. In the numerical model, the fluid pressure at fluid/solid interface is replaced by
a continuum of point sources weighted by the normal acceleration of the elastic plate, and the governing equation system is
solved in the solid domain. With the normal acceleration found, the reflected pressure in the fluid is determined by an integral
expression involving the Green's function. It is demonstrated that an appropriate applied voltage potential across the piezoelectric
layer has the effect of cancelling either the reflected or scattered pressure of the plate at any chosen field points in the
fluid.
Project supported by the National Natural Science Foundation of China (No. 10172039). 相似文献
9.
LIN Chang ZHANG Xiu-Lian 《理论物理通讯》2005,44(2):247-251
The nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation is analytically investigated by using the formally variable separation approach. New analytical solutions for the governing equation of this system have been obtained for dust acoustic waves in a dust plasma for the first time. We derive exact analytical expressions for the general case of the nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation. 相似文献
10.