全文获取类型
收费全文 | 266篇 |
免费 | 2篇 |
国内免费 | 3篇 |
专业分类
化学 | 123篇 |
晶体学 | 1篇 |
力学 | 1篇 |
数学 | 67篇 |
物理学 | 79篇 |
出版年
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 9篇 |
2013年 | 31篇 |
2012年 | 11篇 |
2011年 | 11篇 |
2010年 | 5篇 |
2009年 | 12篇 |
2008年 | 7篇 |
2007年 | 12篇 |
2006年 | 9篇 |
2005年 | 8篇 |
2004年 | 8篇 |
2003年 | 10篇 |
2002年 | 9篇 |
2001年 | 6篇 |
1997年 | 6篇 |
1996年 | 3篇 |
1995年 | 6篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1990年 | 2篇 |
1989年 | 8篇 |
1988年 | 4篇 |
1986年 | 2篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1967年 | 1篇 |
1960年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有271条查询结果,搜索用时 540 毫秒
1.
Debendra K. Mohapatra Dhananjoy Mondal Mukund S. Chorghade Mukund K. Gurjar 《Tetrahedron letters》2006,47(52):9215-9219
The non-proteinogenic amino acid 3-hydroxy-4-methylproline (HMP) is an active constituent of some potent antimicrobials including echinocandins, nostopeptins, pneumocandins, sporiofungin and mulundocandins. A synthesis has been achieved in 10 steps with 29% overall yield; the Evans’ aldol reaction using Crimmins’ modified method was pivotal to the success of the strategy. 相似文献
2.
Mukund K. Gurjar 《Tetrahedron letters》2006,47(39):6979-6981
The synthesis of a chiral cyclic nitrone with l-arabino configuration and its application in the total synthesis of radicamine B is reported. An agreement in the spectral data with natural radicamine B but specific rotation with an opposite sign warranted a revision of the absolute configuration of radicamine B. 相似文献
3.
4.
5.
6.
Eric Chisolm E. C. G. Sudarshan Thomas F. Jordan 《International Journal of Theoretical Physics》1996,35(3):485-493
Griffiths' quantum trajectories formalism is extended to describe weak decoherence. The decoherence conditions are shown to severely limit the complexity of histories composed of fine-grained events. 相似文献
7.
Peng CY Nam WJ Fonash SJ Gu B Sen A Strawhecker K Natarajan S Foley HC Kim SH 《Journal of the American Chemical Society》2003,125(31):9298-9299
We describe the use of hard etching methods to create nanodimensional channels and their use as templates for the formation of polymer filament arrays with precise dimensional and orientational control in a single integrated step. The procedure is general as illustrated by the radical, coordination, and photochemical polymerizations that were performed in these nanochannels. The nanochannel templates (20 nm high, 20-200 nm wide, and 100 mum long) were fabricated by the combined use of electron-beam lithography and a sacrificial metal line etching technique. Radical polymerization of acrylates, metal-catalyzed polymerization of norbornene, and photochemical polymerization of 1,4-diiodothiophene were carried out in these nanochannels. The polymers grown follow the dimensions and orientation of the channels, and the polymer filaments can be released without breaking. The approach opens up the possibility of just-in-place manufacturing and processing of patterns and devices from nanostructured polymers using well-established polymer chemistry. 相似文献
8.
C.V. Ramana Mohabul A. Mondal Vedavati G. Puranik Mukund K. Gurjar 《Tetrahedron letters》2006,47(24):4061-4064
The central macrocyclic core of the macrocidins was constructed using RCM as the key reaction. A preliminary investigation dealing with the key reactions, that is, the Dieckmann cyclization and the RCM, revealed that RCM of the β-ketoamide is better than RCM of the corresponding acyltetramic acid. 相似文献
9.
10.
Patel Anuj P. Shaikh Mohammedumar M. Gurjar Kamlesh K. Chikhalia Kishor H. 《Research on Chemical Intermediates》2021,47(5):2049-2061
Research on Chemical Intermediates - Indenoquinolinones have been synthesized from 2-haloquinoline-3-carbaldehyde through Pd-mediated simultaneous C–H (aldehyde) and C–X bond... 相似文献