全文获取类型
收费全文 | 533篇 |
免费 | 6篇 |
专业分类
化学 | 289篇 |
力学 | 16篇 |
数学 | 45篇 |
物理学 | 189篇 |
出版年
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 3篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2016年 | 7篇 |
2015年 | 6篇 |
2014年 | 3篇 |
2013年 | 32篇 |
2012年 | 20篇 |
2011年 | 25篇 |
2010年 | 22篇 |
2009年 | 14篇 |
2008年 | 19篇 |
2007年 | 27篇 |
2006年 | 16篇 |
2005年 | 13篇 |
2004年 | 18篇 |
2003年 | 20篇 |
2002年 | 17篇 |
2001年 | 11篇 |
2000年 | 16篇 |
1999年 | 18篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 10篇 |
1994年 | 11篇 |
1993年 | 16篇 |
1992年 | 14篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 7篇 |
1985年 | 8篇 |
1984年 | 11篇 |
1983年 | 7篇 |
1982年 | 8篇 |
1981年 | 3篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1977年 | 8篇 |
1976年 | 5篇 |
1974年 | 3篇 |
1973年 | 8篇 |
1904年 | 2篇 |
1878年 | 2篇 |
排序方式: 共有539条查询结果,搜索用时 15 毫秒
21.
22.
23.
Neutron diffraction structure factors for liquid carbon tetrachloride and germanium tetrabromide have been measured and are analysed to determine the molecular centre positional correlation function allowing for molecular angular correlation. The analysis shows quite unequivocally that appreciable molecular orientational correlations must exist in these liquids but that it may only extend to nearest neighbours. This is thought to cause the pair distribution function for the molecular liquids to be markedly different from that for atomic liquids such as argon and the difference is discussed. 相似文献
24.
25.
In this study, flexible silk fibroin protein and biocompatible barium hexaferrite (BaM) nanoparticles were combined and electrospun into nanofibers, and their physical properties could be tuned through the mixing ratios and a water annealing process. Structural analysis indicates that the protein structure of the materials is fully controllable by the annealing process. The mechanical properties of the electrospun composites can be significantly improved by annealing, while the magnetic properties of barium hexaferrite are maintained in the composite. Notably, in the absence of a magnetic field, cell growth increased slightly with increasing BaM content. Application of an external magnetic field during in vitro cell biocompatibility study of the materials demonstrated significantly larger cell growth. We propose a mechanism to explain the effects of water annealing and magnetic field on cell growth. This study indicates that these composite electrospun fibers may be widely used in the biomedical field for controllable cell response through applying different external magnetic fields. 相似文献
26.
Cowan ML Anache-Ménier D Hildebrand WK Page JH van Tiggelen BA 《Physical review letters》2007,99(9):094301
Temporal fluctuations in the phase of waves transmitted through a dynamic, strongly scattering, mesoscopic sample are investigated using ultrasonic waves, and compared with theoretical predictions based on circular Gaussian statistics. The fundamental role of phase in diffusing acoustic wave spectroscopy is revealed, and phase statistics are also shown to provide a sensitive and accurate way to probe scatterer motions at both short and long time scales. 相似文献
27.
Yusof Enis Nadia Md. Ishak Nurul N. M. Latif Muhammad A. M. Tahir Mohamed I. M. Sakoff Jennette A. Page Alister J. Tiekink Edward R. T. Ravoof Thahira B. S. A. 《Research on Chemical Intermediates》2020,46(4):2351-2379
Research on Chemical Intermediates - A series of tridentate ONS Schiff bases were synthesised via condensation by reacting 2,3-dihydroxybenzaldehyde with S-2-methylbenzyldithiocarbazate (S2MBDTC)... 相似文献
28.
CM Silva MF Duarte ML Mira MH Florêncio K Versluis AJ Heck 《Rapid communications in mass spectrometry : RCM》1999,13(12):1098-1103
Fast atom bombardment, combined with high-energy collision-induced tandem mass spectrometry, has been used to investigate gas-phase metal-ion interactions with captopril, enalaprilat and lisinopril, all angiotensin-converting enzyme inhibitors.Suggestions for the location of metal-binding sites are presented. For captopril, metal binding occurs most likely at both the sulphur and the nitrogen atom. For enalaprilat and lisinopril, binding preferably occurs at the amine nitrogen. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
29.
30.