全文获取类型
收费全文 | 6521篇 |
免费 | 172篇 |
国内免费 | 266篇 |
专业分类
化学 | 2876篇 |
晶体学 | 5篇 |
力学 | 122篇 |
综合类 | 24篇 |
数学 | 2443篇 |
物理学 | 1489篇 |
出版年
2023年 | 22篇 |
2022年 | 89篇 |
2021年 | 68篇 |
2020年 | 51篇 |
2019年 | 63篇 |
2018年 | 85篇 |
2017年 | 80篇 |
2016年 | 69篇 |
2015年 | 51篇 |
2014年 | 92篇 |
2013年 | 304篇 |
2012年 | 161篇 |
2011年 | 351篇 |
2010年 | 261篇 |
2009年 | 488篇 |
2008年 | 463篇 |
2007年 | 387篇 |
2006年 | 407篇 |
2005年 | 269篇 |
2004年 | 138篇 |
2003年 | 105篇 |
2002年 | 232篇 |
2001年 | 159篇 |
2000年 | 130篇 |
1999年 | 78篇 |
1998年 | 85篇 |
1997年 | 52篇 |
1996年 | 72篇 |
1995年 | 34篇 |
1994年 | 32篇 |
1993年 | 7篇 |
1992年 | 18篇 |
1991年 | 12篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1985年 | 12篇 |
1984年 | 14篇 |
1982年 | 47篇 |
1981年 | 257篇 |
1980年 | 260篇 |
1979年 | 234篇 |
1978年 | 286篇 |
1977年 | 226篇 |
1976年 | 244篇 |
1975年 | 46篇 |
1974年 | 62篇 |
1973年 | 178篇 |
1972年 | 105篇 |
1969年 | 16篇 |
1947年 | 14篇 |
排序方式: 共有6959条查询结果,搜索用时 0 毫秒
1.
Dan Voiculescu 《Reports on Mathematical Physics》2005,55(1):127-133
This short note summarizes the circumstances of the birth of free probability theory andsome of the recent achievements. 相似文献
2.
Dedushenko S. K. Makhina I. B. Mar'in A. A. Mukhanov V. A. Perfiliev Yu. D. 《Hyperfine Interactions》2004,158(1-4):417-421
A colourless quartz crystal doped with 57Fe3+ was obtained by hydrothermal synthesis in an NH4F solution. The crystal was transformed into violet amethyst by gamma-irradiation. The change in colour was accompanied by changes in the Mössbauer spectrum that can be interpreted as the conversion of trivalent iron into the tetravalent state: Fe3+→Fe4+.
相似文献3.
4.
A new scheme for controlling photodissociation through preparation of a variationally optimized linear superposition of field free vibrational eigenstates is applied for selective control of IBr and HI dissociation. The dependence of photodissociation on various field parameters and initial conditions is examined to investigate the mechanistic basis of selective control. The parametric equations of motion approach for determining vibrational dynamics as a function of field parameters without having to solve the time dependent Schrödinger equation explicitly for each field parameter separately is outlined and its use to identify field characteristics which will provide the requisite population mix represented by the optimal linear superposition of vibrational states is advocated. 相似文献
5.
6.
An effective residual interaction between particles and holes for shell model calculations around 208Pb, derived from the interaction between free nucleons, is compared with the measured properties of proton-hole neutron states
in 208Tl and the interaction between proton holes is adjusted to newly measured level energies in 206Hg. These interaction elements are particularly relevant for neutron-rich nuclei. The adjustment of two mixing elements reproduces
the known γ-decay data in 208Tl.
Received: 2 April 2002 / Accepted: 2 May 2002 相似文献
7.
We study problems of interpolation of positive linear operators in couples of ordered Banach spaces. From this viewpoint, we study couples of noncommutative spaces L 1, L ∞ associated with weights and traces on von Neumann algebras. 相似文献
8.
Catherine Cordier-Robert Thierry Grosdidier Gang Ji Jacques Foct 《Hyperfine Interactions》2006,168(1-3):951-957
Microstructured (atomized) and nanostructured (milled) Fe60Al40 powders together with their corresponding coatings synthesized by High Velocity Oxy-fuel (HVOF) or Atmospheric Plasma Spray (APS) thermal spraying techniques have been characterized by Mössbauer Spectroscopy (MS) and X-ray Diffraction (XRD). The evolution of the microstructure and the atomic ordering degree in the powders and coatings are discussed at the light of the various processing conditions. The operational correlation between the parameters of the duplex morphology of coatings and the processing parameters is discussed. 相似文献
9.
3d-metal antimonides: Fe1+x Sb, N+x Sb, Co+x Sb and the (Ni1?y Fe y )Sb solid solution have been studied by the Mössbauer effect method at 57Fe and 119Sn. It was found that the quadrupole interactions at the Fe and Sn nucleus in 3d-metal antimonides are very sensitive to the filling of different crystallographic sites with metal atoms. The metal atoms in trigonal-bipyramidal sites have a strong effect on the quadrupole splitting of 119Sn. They are nearest to anions (Sb or Sn) with the typical axial ratio of c/a = 1.25. The QS(x) dependence of 119 Sn in 3d-metal antimonides in the 0 ≤ x ≤ 0.1 concentration range can be used to determine x – the concentration of transition metal excess relative to the stoichiometric composition. 相似文献
10.
Márton Kiss 《Acta Mathematica Hungarica》2006,110(3):253-259
Summary New results for the eigenvalue ratios of vibrating strings are presented partially in connection with previous results concerning
Schr?dinger operators. 相似文献