全文获取类型
收费全文 | 7949篇 |
免费 | 232篇 |
国内免费 | 197篇 |
专业分类
化学 | 740篇 |
晶体学 | 18篇 |
力学 | 56篇 |
综合类 | 10篇 |
数学 | 6843篇 |
物理学 | 711篇 |
出版年
2024年 | 6篇 |
2023年 | 14篇 |
2022年 | 45篇 |
2021年 | 43篇 |
2020年 | 43篇 |
2019年 | 197篇 |
2018年 | 191篇 |
2017年 | 111篇 |
2016年 | 80篇 |
2015年 | 94篇 |
2014年 | 220篇 |
2013年 | 455篇 |
2012年 | 260篇 |
2011年 | 453篇 |
2010年 | 433篇 |
2009年 | 563篇 |
2008年 | 623篇 |
2007年 | 601篇 |
2006年 | 491篇 |
2005年 | 360篇 |
2004年 | 269篇 |
2003年 | 228篇 |
2002年 | 199篇 |
2001年 | 164篇 |
2000年 | 166篇 |
1999年 | 197篇 |
1998年 | 169篇 |
1997年 | 135篇 |
1996年 | 195篇 |
1995年 | 184篇 |
1994年 | 171篇 |
1993年 | 136篇 |
1992年 | 120篇 |
1991年 | 82篇 |
1990年 | 59篇 |
1989年 | 68篇 |
1988年 | 52篇 |
1987年 | 49篇 |
1986年 | 40篇 |
1985年 | 68篇 |
1984年 | 47篇 |
1983年 | 31篇 |
1982年 | 56篇 |
1981年 | 43篇 |
1980年 | 26篇 |
1979年 | 30篇 |
1978年 | 24篇 |
1977年 | 24篇 |
1976年 | 29篇 |
1974年 | 10篇 |
排序方式: 共有8378条查询结果,搜索用时 15 毫秒
71.
We study the Besov regularity of conformal mappings for domains with rough boundary based on the well-posedness for the Dirichlet problem with Besov data. Also, sharp invertibility results for the classical layer potential operators on Sobolev-Besov spaces on the boundary of curvilinear polygons are obtained. 相似文献
72.
J. A. Otero H. Cálas R. Rodríguez-Ramos G. A. Maugin G. Monsiváis R. Pérez-Alvarez 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2004,55(3):519-533
The transfer matrix and global matrix techniques are
used in the analysis of diffraction of transverse horizontal waves
in piezoelectric superlattices. The system is composed of a set of
different piezoelectric layers with quasiperiodic structure
according to the Fibonacci sequence. The diffraction spectrum of
different configurations of piezoelectric Fibonacci structures is
studied. Numerical results for the diffraction spectrum for the
piezoelectric Fibonacci superlattice are obtained and a comparison
between the results of the transfer and global matrix methods is
given, exhibiting the advantage of the latter. 相似文献
73.
We give a purely algebro-geometric proof of the fact that every nonsingular
projective curve can be defined over a finite extension of its moduli field.
This extends a result byWolfart [7] to curves over fields of arbitrary
characteristic.
Received: 30 November 2001 相似文献
74.
Chau O. Shillor M. Sofonea M. 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2004,55(1):32-47
A model for the dynamic, adhesive, frictionless contact
between a viscoelastic body and a deformable foundation is
described. The adhesion process is modeled by a bonding field on
the contact surface. The contact is described by a modified normal
compliance condition. The tangential shear due to the bonding
field is included. The problem is formulated as a coupled system
of a variational equality for the displacements and a differential
equation for the bonding field. The existence of a unique weak
solution for the problem is established, together with a partial
regularity result. The existence proof proceeds by construction of
an appropriate mapping which is shown to be a contraction on a
Hilbert space. 相似文献
75.
Masaharu Ishikawa 《Topology》2004,43(1):215-232
In the present paper we generalize the divide lying in the unit disk, introduced by A'Campo, to compact, oriented, smooth surfaces, and prove a fibration theorem for generalized divides. As a consequence, we will show that, for any link L in the tangent circle bundle Y to the compact surface, there exists an additional knot K such that the link L∪K is the binding of a “positive” open book decomposition of Y. 相似文献
76.
77.
The effect of surface modification with 3-aminopropyltriethoxysilane (APTES) and n-propyltriethoxysilane (PTES) on photo-catalytic activity and UV-shielding ability of fine TiO2 particles were investigated. The number of surface groups (NR) [nm−2] which shows the density of modifier on TiO2 surface was calculated from the results of elemental analysis and BET measurement. The modified samples of which NR are different were obtained by changing the concentration of modifier. When the photo-catalytic activity and UV-shielding ability of modified samples were evaluated, it was found that APTES was more effective modifier than PTES to obtained samples with low photo-catalytic activity and high UV-shielding ability. This is probably because the adsorption mechanisms on TiO2 surface between modifiers were different and NR is a key factor to control the performances of fine TiO2 particles. The result of zeta potential showed that surface character of modified samples was varied by changing NR. It suggested from these results that NR affected the photo-catalytic activity and UV-shielding ability because NR changed surface character of modified samples. 相似文献
78.
79.
80.