全文获取类型
收费全文 | 107篇 |
免费 | 4篇 |
国内免费 | 1篇 |
专业分类
化学 | 49篇 |
数学 | 3篇 |
物理学 | 60篇 |
出版年
2022年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2017年 | 2篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 8篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2010年 | 1篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 7篇 |
2005年 | 2篇 |
2004年 | 7篇 |
2003年 | 2篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 1篇 |
1992年 | 7篇 |
1991年 | 3篇 |
1990年 | 11篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有112条查询结果,搜索用时 15 毫秒
11.
Schumm BA Koetke DS Adolphsen CE Alexander JP Averill D Barish BC Barklow T Barnett BA Blockus D Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan JM Drell PS Drewer DC Durrett D Elia R Feldman GJ Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Hanson G Harr R Harral B Harris FA Hayes K Hearty C Heusch CA Hildreth MD Himel T Hinshaw DA 《Physical review D: Particles and fields》1992,46(1):453-456
12.
13.
14.
The reaction of malononitrile with α-phenylcinnamonitriles in ethanolic sodium ethanethiolate is studied as a convenient route to 2-amino-4-aryl-5-cyano-6-ethylthio-3-phenyl-3,4-dihydropyridines ( 5 ) and the corresponding pyridines 6 . From the study of the structure of 5a (Ar = Ph) we can conclude that this cyclization reaction proceeds via a site-selective addition of the ethanethiolate to the cyano group i of the 1,3-tricarbonitrile ( 2 ). 相似文献
15.
Background
Growth hormone (GH) plays an incompletely understood role in the development of the central nervous system (CNS). In this study, we use transgenic mice expressing a growth hormone antagonist (GHA) to explore the role of GH in regulating postnatal brain, spinal cord and body growth into adulthood. The GHA transgene encodes a protein that inhibits the binding of GH to its receptor, specifically antagonizing the trophic effects of endogenous GH. 相似文献16.
Gomez L Slutzky C Ferron J de La Figuera J Camarero J Vazquez De Parga AL de Miguel JJ Miranda R 《Physical review letters》2000,84(19):4397-4400
Generic computer simulations using empiric interatomic potentials suggest a new, collective mechanism that could be responsible for mixing at heteroepitaxial interfaces. Even if single adsorbate atoms diffuse by hopping on the substrate surface and do not mix at the terraces, two-dimensional islands formed by nucleation may become unstable above a certain critical size and explode upwards forming clusters of several atomic layers. This process is accompanied by strong distortions of the underlying atomic layers, and on soft materials it can result in surface etching and incorporation of substrate atoms into the islands. 相似文献
17.
The properties of the negative parity states of55Fe and57Fe are investigated in the framework of the intermediate coupling model. In the model, a neutron or a quasineutron is coupled to anharmonic vibrations of the core. Anharmonicities of the vibrations are estimated through the observed properties of the core. Energy levels, spectroscopic factors and electromagnetic properties have been calculated. The results of the present calculations are also compared with available experimental results and other theoretical results. The model reasonably accounts for many of the properties of the low-lying states. 相似文献
18.
19.
[reaction: see text]. Alpha-carbolines are interesting core structures for designing DNA-interacting small molecules. However, these compounds are not commercially available and their synthetic methods are low yielding or time consuming. The shortest synthetic route, the modified Graebe-Ullmann reaction, has been optimized by using microwave heating in four different types of apparatus to give shorter reaction times and enhanced yields. Optimized conditions enabled the preparation of a small library of alpha-carbolines. 相似文献
20.
Castellote I Morón M Burgos C Alvarez-Builla J Martin A Gómez-Sal P Vaquero JJ 《Chemical communications (Cambridge, England)》2007,(12):1281-1283
Imines react with N-iodosuccinimide (NIS) to afford unexpected 1 : 1 complexes and the structure of one of these was determined by single-crystal X-ray diffraction; the reaction seems to be very general for substituted cyclic imines with solid stable complexes obtained in high yields; this is the first reported example of a halogen bonding interaction involving the C=N bond and NIS. 相似文献