全文获取类型
收费全文 | 3470篇 |
免费 | 699篇 |
国内免费 | 203篇 |
专业分类
化学 | 218篇 |
晶体学 | 10篇 |
力学 | 1420篇 |
综合类 | 23篇 |
数学 | 295篇 |
物理学 | 1224篇 |
综合类 | 1182篇 |
出版年
2024年 | 12篇 |
2023年 | 30篇 |
2022年 | 62篇 |
2021年 | 67篇 |
2020年 | 93篇 |
2019年 | 110篇 |
2018年 | 72篇 |
2017年 | 122篇 |
2016年 | 140篇 |
2015年 | 137篇 |
2014年 | 173篇 |
2013年 | 234篇 |
2012年 | 197篇 |
2011年 | 227篇 |
2010年 | 152篇 |
2009年 | 223篇 |
2008年 | 184篇 |
2007年 | 211篇 |
2006年 | 178篇 |
2005年 | 168篇 |
2004年 | 176篇 |
2003年 | 168篇 |
2002年 | 131篇 |
2001年 | 130篇 |
2000年 | 124篇 |
1999年 | 104篇 |
1998年 | 70篇 |
1997年 | 92篇 |
1996年 | 84篇 |
1995年 | 84篇 |
1994年 | 84篇 |
1993年 | 56篇 |
1992年 | 69篇 |
1991年 | 41篇 |
1990年 | 51篇 |
1989年 | 34篇 |
1988年 | 34篇 |
1987年 | 15篇 |
1986年 | 9篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1978年 | 1篇 |
1973年 | 1篇 |
1971年 | 2篇 |
1957年 | 2篇 |
1955年 | 1篇 |
排序方式: 共有4372条查询结果,搜索用时 31 毫秒
1.
Volker Elling. 《Mathematics of Computation》2006,75(256):1721-1733
A particular case of initial data for the two-dimensional Euler equations is studied numerically. The results show that the Godunov method does not always converge to the physical solution, at least not on feasible grids. Moreover, they suggest that entropy solutions (in the weak entropy inequality sense) are not well posed.
2.
3.
4.
Marko Nedeljkov 《Mathematical Methods in the Applied Sciences》2004,27(8):931-955
This work gives a condition for existence of singular and delta shock wave solutions to Riemann problem for 2×2 systems of conservation laws. For a fixed left‐hand side value of Riemann data, the condition obtained in the paper describes a set of possible right‐hand side values. The procedure is similar to the standard one of finding the Hugoniot locus. Fluxes of the considered systems are globally Lipschitz with respect to one of the dependent variables. The association in a Colombeau‐type algebra is used as a solution concept. Copyright © 2004 John Wiley &Sons, Ltd. 相似文献
5.
The thermal and thermo-elastic-plastic response of newly developed ceramic-metalfunctionally graded materials under a thermal shock load is studied.The materials are heated at the ce-ramic surface with a sudden high-intensity heat flux input,and cooled at the metal surface with aflowing liquid nitrogen.Emphasis is placed on two aspects:(1)the influence of the graded composi-tion of the materials on the temperature and stress response;and(2)the optimum design of the gradedcomposition from a unified viewpoint of the heat insulation property and stress relaxation property.Moreover,a comparison between the thermoelastic stress and the thermo-elastic-plastic stress is alsomade to indicate the plasticity effect. 相似文献
6.
7.
8.
9.
The use of liquid fuels such as kerosene is of interest for the pulse detonation engine (PDE). Within this context, the aim
of this work, which is a preliminary study, was to show the feasibility to initiate a detonation in air with liquid-fuel pyrolysis
products, using energies and dimensions of test facility similars to those of PDEs. Therefore, two liquids fuels have been
compared, JP10, which is a synthesis fuel generally used in the field of missile applications, and decane, which is one of
the major components of standard kerosenes (F-34, Jet A1, ...). The thermal degradation of these fuels was studied with two
pyrolysis processes, a batch reactor and a flow reactor. The temperatures varied from 600°C to 1,000°C and residence times
for the batch reactor and the flow reactor were, respectively, between 10–30 s and 0.1–2 s. Subsequently, the detonability
of synthetic gaseous mixtures, which was a schematisation of the decomposition state after the pyrolysis process, has been
studied. The detonability study, regarding nitrogen dilution and equivalence ratio, was investigated in a 50 mm-diameter,
2.5 m-long detonation tube. These dimensions are compatible with applications in the aircraft industry and, more particularly,
in PDEs. Therefore, JP10 and decane were compared to choose the best candidate for liquid-fuel PDE studies.
This paper was based on work that was presented at the 20th International Colloquium on the Dynamics of Explosions and Reactive
Systems, Montreal, Canada, July 31 – August 5, 2005. 相似文献
10.
R. S. Srivastava 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2007,58(5):832-842
The diffraction of normal shock with yawed wedges of small angles have been considered in this paper. Vorticity distribution
of the fluid particle over the diffracted shock has been determined for several Mach numbers of the shock wave. The Mach reflection
effects have also been investigated when the bend is concave to the flow. 相似文献