全文获取类型
收费全文 | 91篇 |
免费 | 9篇 |
国内免费 | 4篇 |
专业分类
化学 | 75篇 |
数学 | 11篇 |
物理学 | 18篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 5篇 |
2020年 | 8篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 1篇 |
2016年 | 7篇 |
2015年 | 4篇 |
2014年 | 7篇 |
2013年 | 1篇 |
2012年 | 9篇 |
2011年 | 3篇 |
2010年 | 2篇 |
2009年 | 6篇 |
2008年 | 10篇 |
2007年 | 7篇 |
2006年 | 6篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1994年 | 2篇 |
1991年 | 1篇 |
排序方式: 共有104条查询结果,搜索用时 15 毫秒
101.
We elucidate the dependence of purity and entanglement of two-photon states generated by spontaneous parametric down-conversion on the parameters of the source, such as crystal length, pump beam divergence, frequency bandwidth, and detectors angular aperture. The effect of crystal anisotropy is taken into account. Numerical simulations are presented for two types of commonly used source configurations. 相似文献
102.
I.L. Menezes-Sobrinho J.G. Moreira A.T. Bernardes 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,13(2):313-318
We study the existence of distinct failure regimes in a model for fracture in fibrous materials. We simulate a bundle of parallel
fibers under uniaxial static load and observe two different failure regimes: a catastrophic and a slowly shredding. In the
catastrophic regime the initial deformation produces a crack which percolates through the bundle. In the slowly shredding
regime the initial deformations will produce small cracks which gradually weaken the bundle. The boundary between the catastrophic
and the shredding regimes is studied by means of percolation theory and of finite-size scaling theory. In this boundary, the
percolation density scales with the system size L, which implies the existence of a second-order phase transition with the same critical exponents as those of usual percolation.
Received 24 June 1999 相似文献
103.
104.