全文获取类型
收费全文 | 436篇 |
免费 | 7篇 |
专业分类
化学 | 258篇 |
晶体学 | 7篇 |
力学 | 1篇 |
数学 | 14篇 |
物理学 | 163篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 10篇 |
2019年 | 8篇 |
2018年 | 11篇 |
2017年 | 3篇 |
2016年 | 5篇 |
2015年 | 9篇 |
2014年 | 10篇 |
2013年 | 22篇 |
2012年 | 18篇 |
2011年 | 23篇 |
2010年 | 17篇 |
2009年 | 23篇 |
2008年 | 24篇 |
2007年 | 24篇 |
2006年 | 20篇 |
2005年 | 18篇 |
2004年 | 14篇 |
2003年 | 19篇 |
2002年 | 14篇 |
2001年 | 10篇 |
2000年 | 18篇 |
1999年 | 8篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 8篇 |
1993年 | 2篇 |
1992年 | 14篇 |
1991年 | 10篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 5篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1966年 | 1篇 |
1937年 | 1篇 |
1936年 | 1篇 |
排序方式: 共有443条查询结果,搜索用时 578 毫秒
441.
Mami Miyairi Dr. Tsuyoshi Taniguchi Dr. Tatsuya Nishimura Prof. Katsuhiro Maeda 《Angewandte Chemie (International ed. in English)》2023,62(37):e202302332
Improved methods for the synthesis of linear and cyclic poly(diphenylacetylene)s by polymerization of the corresponding diphenylacetylenes using MoCl5- and WCl4-based catalytic systems have been developed. MoCl5 induces migratory insertion polymerization of diphenylacetylenes in the presence of arylation reagents such as Ph4Sn and ArSnnBu3 to produce cis-stereoregular linear poly(diphenylacetyelene)s with high molecular weights (number-average molar mass (Mn)=30,000–3,200,000) in good yields (up to 98 %). On the other hand, WCl4 induces ring expansion polymerization of diphenylacetylenes in the presence of Ph4Sn or reducing reagents to produce cis-stereoregular cyclic poly(diphenylacetylene)s with high molecular weights (Mn=20,000–250,000) in moderate to good yields (up to 90 %). Both catalytic systems are applicable to the polymerization of various diphenylacetylenes having polar functional groups such as esters that are not efficiently polymerized by conventional methods using WCl6-Ph4Sn and TaCl5-nBu4Sn systems. 相似文献
442.
443.
Youxin Fu Jun.-Prof. Dr. Nadja A. Simeth Dr. Ryojun Toyoda Dr. Robert Brilmayer Prof. Dr. Wiktor Szymanski Prof. Dr. Ben L. Feringa 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218203
Light-induced 9,10-phenanthrenequinone-electron-rich alkene ( PQ-ERA ) photocycloadditions are an attractive new type of photoclick reaction, featuring fast conversions and high biocompatibility. However, the tunability of the reaction was hardly investigated up to now. To this end, we explored the influence of substituents on both reaction partners and the reaction rate between the PQs and ERAs . We identified new handles for functionalization and discovered that using enamines as ERAs leads to drastically enhanced rates (>5400 times faster), high photoreaction quantum yields ( ΦP , up to 65 %), and multicolor emission output as well as a high fluorescence quantum yield of the adducts ( ΦF , up to 97 %). Further investigation of the photophysical and photochemical properties provided insights to design orthogonal reaction systems both in solution and on nanoparticle surfaces for ultrafast chemoselective functionalization by photoclick reactions. 相似文献