全文获取类型
收费全文 | 183篇 |
免费 | 27篇 |
国内免费 | 3篇 |
专业分类
化学 | 183篇 |
晶体学 | 1篇 |
数学 | 8篇 |
物理学 | 21篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 7篇 |
2017年 | 1篇 |
2016年 | 15篇 |
2015年 | 14篇 |
2014年 | 8篇 |
2013年 | 11篇 |
2012年 | 15篇 |
2011年 | 18篇 |
2010年 | 3篇 |
2009年 | 3篇 |
2008年 | 12篇 |
2007年 | 18篇 |
2006年 | 14篇 |
2005年 | 7篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2002年 | 10篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有213条查询结果,搜索用时 0 毫秒
211.
Yutaka Hemmi Teiichi Kobayashi Kazushi Komatsu 《Topology and its Applications》2009,156(15):2485-2490
Let Ln(3) denote the (2n+1)-dimensional standard lens space mod 3. In this paper, we study the conditions for a given real vector bundle over Ln(3) to be stably extendible to Lm(3) for every mn, and establish the formula on the power ζk=ζζ (k-fold) of a real vector bundle ζ over Ln(3). Moreover, we answer the stable splitting problem for real vector bundles over Ln(3) by means of arithmetic conditions. 相似文献
212.
Chloride‐Bridged Dinuclear Rhodium(III) Complexes Bearing Chiral Diphosphine Ligands: Catalyst Precursors for Asymmetric Hydrogenation of Simple Olefins 下载免费PDF全文
Dr. Yusuke Kita Shoji Hida Kenya Higashihara Dr. Himanshu Sekhar Jena Kosuke Higashida Prof. Dr. Kazushi Mashima 《Angewandte Chemie (International ed. in English)》2016,55(29):8299-8303
Efficient rhodium(III) catalysts were developed for asymmetric hydrogenation of simple olefins. A new series of chloride‐bridged dinuclear rhodium(III) complexes 1 were synthesized from the rhodium(I) precursor [RhCl(cod)]2, chiral diphosphine ligands, and hydrochloric acid. Complexes from the series acted as efficient catalysts for asymmetric hydrogenation of (E)‐prop‐1‐ene‐1,2‐diyldibenzene and its derivatives without any directing groups, in sharp contrast to widely used rhodium(I) catalytic systems that require a directing group for high enantioselectivity. The catalytic system was applied to asymmetric hydrogenation of allylic alcohols, alkenylboranes, and unsaturated cyclic sulfones. Control experiments support the superiority of dinuclear rhodium(III) complexes 1 over typical rhodium(I) catalytic systems. 相似文献
213.
Darryl F. Nater Christoph J. Kaul Lukas Lätsch Hayato Tsurugi Kazushi Mashima Christophe Copéret 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(22):e202200559
Tailored molybdenum(VI)-oxo complexes of the form MoOCl2(OR)2(OEt2) catalyse olefin metathesis upon reaction with an organosilicon reducing agent at 70 °C, in the presence of olefins. While this reactivity parallels what has recently been observed for the corresponding classical heterogeneous catalysts based on supported metal oxide under similar conditions, the well-defined nature of our starting molecular systems allows us to understand the influence of structural, spectroscopic and electronic characteristics of the catalytic precursor on the initiation and catalytic proficiency of the final species. The catalytic performances of the pre-catalysts are determined by the highly electron withdrawing (σ-donation) character of alkoxide ligands, OtBuF9 being the best. This activity correlates with both the 95Mo chemical shift and the reduction potential that follows the same trend: OtBuF9>OtBuF6>OtBuF3. 相似文献