全文获取类型
收费全文 | 50篇 |
免费 | 3篇 |
专业分类
化学 | 33篇 |
力学 | 3篇 |
数学 | 2篇 |
物理学 | 15篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 5篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 1篇 |
2009年 | 3篇 |
2008年 | 2篇 |
2007年 | 1篇 |
2006年 | 5篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2001年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有53条查询结果,搜索用时 6 毫秒
51.
52.
Elías Quezada Giovanna Delogu Dolores Viña Lourdes Santana Gianni Podda Maria Joao Matos Carmen Picciau 《Helvetica chimica acta》2009,92(7):1309-1314
Arenofurans have important biological and pharmacological activities. Compared to benzofurans, the reports on the synthesis of benzodifurans are rather limited. Here, we report the synthesis of a linear and an angular 3,3′‐bis(carboxymethyl)substituted benzodifuran and 4′‐carboxymethyl‐substituted angelicins from phloroglucinol, using 4‐halomethyl‐substituted dipyrones as key intermediates in the synthetic route. This strategy shows that the stability of a pyrone ring depends on the type of substituent at C(4) and the conditions used. 相似文献
53.
C. Saldías A. Leiva C. Quezada P. Jaque L. Gargallo D. Radic 《European Polymer Journal》2011,47(10):1866-1876
Geometric and multi-arms gold nanoplates were synthesized by direct reaction between two different amphiphilic block copolymers and KAuCl4 in aqueous solution. Amphiphilic copolymers containing blocks of ε-caprolactone and N-vinyl-2-pyrrolidone were used. The block copolymer structures and concentration play a key role on the morphology and size of gold nanoparticles. Copolymers have a dual function as reductant and stabilizer agent. The gold nanoparticles obtained were characterized by transmission electron microscopy (TEM), UV–visible spectroscopy (UV–vis) and dynamic light scattering (DLS). On the other hand, electronic structure calculations, based on density functional theory were performed to support the experimental results. The simple models built with small clusters of gold and co-monomer units provide planar structures complexes with higher stabilization energies. These results agree with the nanoplates obtained experimentally. Moreover, the reactivity analysis based on monoelectronic properties suggests that the formation of aggregates between complexes is favored. 相似文献