全文获取类型
收费全文 | 347篇 |
免费 | 2篇 |
国内免费 | 2篇 |
专业分类
化学 | 345篇 |
力学 | 1篇 |
数学 | 1篇 |
物理学 | 4篇 |
出版年
2020年 | 6篇 |
2019年 | 36篇 |
2018年 | 7篇 |
2017年 | 21篇 |
2016年 | 9篇 |
2015年 | 9篇 |
2014年 | 16篇 |
2013年 | 9篇 |
2012年 | 15篇 |
2011年 | 19篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 10篇 |
2007年 | 9篇 |
2006年 | 8篇 |
2005年 | 11篇 |
2004年 | 4篇 |
2003年 | 10篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 6篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 5篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1982年 | 2篇 |
1981年 | 9篇 |
1980年 | 15篇 |
1979年 | 11篇 |
1978年 | 17篇 |
1977年 | 14篇 |
1976年 | 12篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 12篇 |
1972年 | 10篇 |
1969年 | 1篇 |
1947年 | 1篇 |
排序方式: 共有351条查询结果,搜索用时 31 毫秒
11.
12.
13.
14.
Tingting Yan Dr. Binglei Song Dr. Xiaomei Pei Prof. Zhenggang Cui Prof. Bernard P. Binks Dr. Hengquan Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(2):647-651
A surfactant, R-6-AO, derived from dehydroabietic acid has been synthesized. It behaves as a highly efficient low-molecular-weight hydrogelator with an extremely low critical gelation concentration (CGC) of 0.18 wt % (4 mm ). R-6-AO not only stabilizes oil-in-water (O/W) emulsions at concentrations above its critical micelle concentration (cmc) of 0.6 mm , but also forms gel emulsions at concentrations beyond the CGC with the oil volume fraction freely adjustable between 2 % and 95 %. Cryo-TEM images reveal that R-6-AO molecules self-assemble into left-handed helical fibers with cross-sectional diameters of about 10 nm in pure water, which can be turned to very stable hydrogels at concentrations above the CGC. The gel emulsions stabilized by R-6-AO can be prepared with different oils (n-dodecane, n-decane, n-octane, soybean oil, olive oil, tricaprylin) owing to the tricyclic diterpene hydrophobic structure in their molecules that enables them to adopt a unique arrangement in the fibers. 相似文献
15.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(31):9345-9349
The first catalytic enantioselective asymmetric aza‐pinacol rearrangement is reported. The reactions are catalyzed by a chiral phosphoric acid and proceed via a highly organized transition state involving a cyclic aza‐ortho ‐xylylene intermediate to afford the indoline structures with good to excellent enantioselectivity. The synthetic utility of this method is demonstrated by the asymmetric synthesis of a key intermediate to the natural product minfiensine and the identification of a chiral lead compound to repress antibiotic resistance. 相似文献
16.
17.
18.
19.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(25):7287-7291
Conventional photoelectrochemical cells utilize solar energy to drive the chemical conversion of water or CO2 into useful chemical fuels. Such processes are confronted with general challenges, including the low intrinsic activities and inconvenient storage and transportation of their gaseous products. A photoelectrochemical approach is proposed to drive the reductive production of industrial building‐block chemicals and demonstrate that succinic acid and glyoxylic acid can be readily synthesized on Si nanowire array photocathodes free of any cocatalyst and at room temperature. These photocathodes exhibit a positive onset potential, large saturation photocurrent density, high reaction selectivity, and excellent operation durability. They capitalize on the large photovoltage generated from the semiconductor/electrolyte junction to partially offset the required external bias, and thereby make this photoelectrosynthetic approach significantly more sustainable compared to traditional electrosynthesis. 相似文献