全文获取类型
收费全文 | 3932篇 |
免费 | 668篇 |
国内免费 | 341篇 |
专业分类
化学 | 521篇 |
晶体学 | 88篇 |
力学 | 332篇 |
综合类 | 40篇 |
数学 | 1403篇 |
物理学 | 2557篇 |
出版年
2024年 | 5篇 |
2023年 | 32篇 |
2022年 | 105篇 |
2021年 | 76篇 |
2020年 | 102篇 |
2019年 | 90篇 |
2018年 | 87篇 |
2017年 | 84篇 |
2016年 | 102篇 |
2015年 | 96篇 |
2014年 | 177篇 |
2013年 | 306篇 |
2012年 | 178篇 |
2011年 | 178篇 |
2010年 | 199篇 |
2009年 | 258篇 |
2008年 | 243篇 |
2007年 | 254篇 |
2006年 | 235篇 |
2005年 | 219篇 |
2004年 | 178篇 |
2003年 | 185篇 |
2002年 | 225篇 |
2001年 | 166篇 |
2000年 | 166篇 |
1999年 | 158篇 |
1998年 | 146篇 |
1997年 | 103篇 |
1996年 | 69篇 |
1995年 | 67篇 |
1994年 | 59篇 |
1993年 | 40篇 |
1992年 | 37篇 |
1991年 | 33篇 |
1990年 | 23篇 |
1989年 | 26篇 |
1988年 | 28篇 |
1987年 | 27篇 |
1986年 | 30篇 |
1985年 | 31篇 |
1984年 | 17篇 |
1983年 | 9篇 |
1982年 | 20篇 |
1981年 | 12篇 |
1980年 | 6篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1977年 | 11篇 |
1976年 | 12篇 |
1972年 | 4篇 |
排序方式: 共有4941条查询结果,搜索用时 15 毫秒
51.
Solid solutions of CsCl-Br in five different concentrations were prepared in sealed quartz tubes by heating the mixture to
1123°K for 6–8 hr and quenching to room temperature. X-ray diffractograms were taken at eight different temperatures between
room temperature and 90°K for these solid solutions using the YPC50NM powder diffractometer and a continuous flow cryostat.
The observed lattice parameters for each sample at each temperature obtained from the powder diffractograms were then extrapolated
to give the true lattice parameters using the least square method with Nelson-Riley extrapolation scheme. The values of the
true lattice parameters at each concentration and at each temperature were tabulated and the results discussed. It is shown
that the lattice parameters vs temperature for some concentrations exhibit an anomalous behaviour.
Contribution No. 691 相似文献
52.
G. A. Kohring 《Journal of statistical physics》1992,66(3-4):1177-1184
A hydrodynamic cellular automata (HDCA) for simulating two-dimensional fluids with large viscosities is proposed. The model is characterized by a mean free path which is of the same size as in the FHP-II model, but with a viscosity more than 10 times larger. This new model should make simulations of flows at low Reynolds number more efficient. 相似文献
53.
54.
55.
A. Loidl A. Krimmel K. Knorr G. Sparn M. Lang C. Geibel S. Horn A. Grauel F. Steglich B. Welslau N. Grewe H. Nakotte F. R. de Boer A. P. Murani 《Annalen der Physik》1992,504(2):78-91
Elastic and inelastic neutron-scattering studies on the system Ce(Cu1?xNix)2Ge2 are reported. These measurements are complemented by measurements of the magnetic susceptibility, high-field magnetization, heat capacity, thermal expansion, electrical resistivity and thermopower. The results reveal an interesting T-x phase diagram consisting of two different antiferromagnetic phases for x < 0.2 and 0.2 < x < 0.75, respectively, and a heavy-Fermi-liquid regime at higher Ni concentrations. The experimental results are interpreted in terms of an alloying-induced transition from local-moment to itinerant heavy-fermion magnetism. Fingerprints of this latter phase are a strongly reduced ordered moment and a short incommensurate ordering wave vector, in accord with theoretical predictions. A surprisingly good agreement between theory and experiment is found for x > 0.5. Further experimental evidence for different types of antiferromagnetic ordering derives from a line-shape analysis of the quasielastic neutron-scattering intensity, from magnetization and thermopower experiments. 相似文献
56.
多目标最优化的一种积分型实现算法 总被引:2,自引:1,他引:1
在文[1]中给出了求解多目标最优化的一种积分总极值的概念性算法.本文利用数论中的一致分布佳点集列,较为简便的得出了多目标最优化的积分总极值的实现算法和算法终止准则.并经过有关函数数值计算表明该算法是有效的,可用来求解多目标最优化问题的有效解. 相似文献
57.
We prove that the tolerance lattice TolA of an algebra A from a congruence modular variety V is 0-1 modular and satisfies the general disjointness property. If V is congruence distributive, then the lattice Tol A is pseudocomplemented. If V admits a majority term, then Tol A is 0-modular.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
58.
高压下某些导电高分子色散关系的研究 总被引:1,自引:0,他引:1
利用晶格动力学方法,研究在高压下几种导电高分子具有不同晶格链时的色散关系及其曲线的变化.链间耦合作用的减弱使横波与纵波的ω差值相应增大,且在BZ边界处拉开一个间隙,这是维度作用的结果. 相似文献
59.
We consider the varieties of lattice ordered groups with the identity of commutation of the nth powers of elements. We establish that every such l-variety with n=pq, where p and q are distinct prime numbers, has a finite basis of identities. 相似文献
60.
Breathers in discrete nonlinear ferrimagnetic spin lattices are investigated for both easy-axis and easy-plane configurations.
The region in frequency space of the formation of breathers is determined and the anticontinuum limit discussed. The monochromatic
and the coloured breathers are found out numerically for different parameters and different conditions of excitations. 相似文献