全文获取类型
收费全文 | 119篇 |
免费 | 0篇 |
专业分类
化学 | 19篇 |
晶体学 | 12篇 |
物理学 | 88篇 |
出版年
2017年 | 1篇 |
2013年 | 2篇 |
2012年 | 3篇 |
2011年 | 3篇 |
2010年 | 5篇 |
2009年 | 4篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2005年 | 3篇 |
2004年 | 4篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 16篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 5篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1977年 | 2篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有119条查询结果,搜索用时 12 毫秒
1.
2.
3.
R. L. S. Devine C. T. Foxon B. A. Joyce J. B. Clegg J. P. Gowers 《Applied Physics A: Materials Science & Processing》1987,44(2):195-200
Beryllium diffusion during MBE growth of (Al, Ga)As layers, (Al, Ga)As/GaAs heterojunctions and GaAs/AlAs superlattices has been studied by electrochemical C-V and secondary ion mass spectrometry (SIMS) concentration profiling, in conjunction with transmission electron microscopy. Diffusion times were comparatively short since they were limited to part of the growth sequence, so non-equilibrium effects had a significant influence. The results are consistent with an interstitial-substitutional mechanism in which lattice site incorporation becomes more difficult with increasing band gap enthalpy. Incorporation involves a kick-out reaction which leads to the observed disordering of the superlattices. 相似文献
4.
5.
S. M. Smith N. J. Cronin R. J. Nicholas M. A. Brummell J. J. Harris C. T. Foxon 《International Journal of Infrared and Millimeter Waves》1987,8(8):793-802
We have shown that a Ga1–xAlxAs/GaAs heterostructure can be used as a sensitive tunable detector of mm-wave/sub-mm-wave radiation. The mechanism for detection requires the application of a magnetic field varying from approximately 0.2T at 94GHz (3.2mm wavelength) to 6.2T at 2500GHz (119m wavelength). The responsivity and N.E.P. at 3.2mm have been roughly estimated at 200V/W and 5×10–11W/Hz respectively. The speed of such a detector could be several orders of magnitude greater than comparable InSb detectors. 相似文献
6.
7.
8.
9.
10.
Dr. Benjamin J. Coe Dr. Simon P. Foxon Dr. Madeleine Helliwell Dr. Daniela Rusanova Dr. Bruce S. Brunschwig Prof. Dr. Koen Clays Griet Depotter Dr. Marcin Nyk Prof. Dr. Marek Samoc Dominika Wawrzynczyk Prof. Dr. Javier Garín Dr. Jesús Orduna 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6613-6629
New complexes with six ferrocenyl (Fc) groups connected to ZnII or CdII tris(2,2′‐bipyridyl) cores are described. A thorough characterisation of their BPh4? salts includes two single‐crystal X‐ray structures, highly unusual for such species with multiple, extended substituents. Intense, visible d(FeII)→π* metal‐to‐ligand charge‐transfer (MLCT) bands accompany the π→π* intraligand charge‐transfer absorptions in the near UV region. Each complex shows a single, fully reversible FeIII/II wave when probed electrochemically. Molecular quadratic nonlinear optical (NLO) responses are determined by using hyper‐Rayleigh scattering and Stark spectroscopy. The latter gives static first hyperpolarisabilities β0 reaching as high as approximately 10?27 esu and generally increasing with π‐conjugation extension. Z‐scan cubic NLO measurements reveal high two‐photon absorption cross‐sections σ2 of up to 5400 GM in one case. DFT calculations reproduce the π‐conjugation dependence of β0, and TD‐DFT predicts three transitions close in energy contributing to the MLCT bands. The lowest energy transition has octupolar character, whereas the other two are degenerate and dipolar in nature. 相似文献