全文获取类型
收费全文 | 623篇 |
免费 | 112篇 |
国内免费 | 136篇 |
专业分类
化学 | 705篇 |
晶体学 | 41篇 |
力学 | 1篇 |
综合类 | 3篇 |
物理学 | 121篇 |
出版年
2024年 | 2篇 |
2023年 | 6篇 |
2022年 | 15篇 |
2021年 | 30篇 |
2020年 | 42篇 |
2019年 | 29篇 |
2018年 | 22篇 |
2017年 | 20篇 |
2016年 | 50篇 |
2015年 | 22篇 |
2014年 | 40篇 |
2013年 | 81篇 |
2012年 | 42篇 |
2011年 | 40篇 |
2010年 | 34篇 |
2009年 | 39篇 |
2008年 | 49篇 |
2007年 | 27篇 |
2006年 | 33篇 |
2005年 | 29篇 |
2004年 | 41篇 |
2003年 | 41篇 |
2002年 | 22篇 |
2001年 | 9篇 |
2000年 | 7篇 |
1999年 | 6篇 |
1998年 | 13篇 |
1997年 | 13篇 |
1996年 | 16篇 |
1995年 | 11篇 |
1994年 | 13篇 |
1993年 | 8篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 2篇 |
排序方式: 共有871条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
《Angewandte Chemie (International ed. in English)》2017,56(20):5620-5624
The metastable binary compound hp‐CuBi was obtained from the direct chemical reaction between copper and bismuth at a pressure of 5 GPa and a temperature of 720 K. The atomic arrangement comprises slabs of puckered Cu layers sandwiched between Bi planes. The QTAIM charges calculated for compounds of bismuth with transition metals reveal negligible charge transfer for hp‐CuBi. Analysis of the chemical bonding with position‐space techniques discloses multicenter interactions within the Bi‐Cu‐Bi slabs and lone‐pair interactions of the van der Waals type between these entities. hp‐CuBi exhibits metal‐type electrical conductivity with superconductivity below Tc=1.3 K. 相似文献
25.
《Angewandte Chemie (International ed. in English)》2017,56(43):13253-13258
Reactions of [K(crypt‐222)]2(TlBi3)⋅0.5 en ( 1 b ) with [Ru(cod)(H2CC(Me)CH2)2] ( A ) in 1,2‐diaminoethane (en) led to the formation of two compounds with new bismuth‐rich cluster anions, [K(crypt‐222)]3[Bi9{Ru(cod)}2]⋅1.5 en ( 2 ) and [K(crypt‐222)]2[Tl2Bi6{Ru(cod)}]⋅2 tol ( 3 ), alongside the salt of a binary nido cluster, [K(crypt‐222)]3(Tl4Bi5)⋅2 en ( 4 ). The anions in 2 and 3 are two further examples of rare heterometallic clusters containing Ru atoms. As one cod ligand is retained on each Ru atom in both clusters, the anions may be viewed as intermediates on the way towards larger, ligand‐free intermetalloid clusters. Quantum‐chemical studies provided insight into the bonding situation in these clusters. According to these studies, the anion of 2 features both electron‐precise and electron‐deficient parts. Electrospray ionization mass spectrometry analysis indicated that the clusters undergo stepwise fragmentation. 相似文献
26.
27.
28.
29.
Peilin Deng Fan Yang Zhitong Wang Shenghua Chen Yinzheng Zhou Shahid Zaman Prof. Dr. Bao Yu Xia 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(27):10899-10905
Carbon dioxide (CO2) conversion is promising in alleviating the excessive CO2 level and simultaneously producing valuables. This work reports the preparation of carbon nanorods encapsulated bismuth oxides for the efficient CO2 electroconversion toward formate production. This resultant catalyst exhibits a small onset potential of −0.28 V vs. RHE and partial current density of over 200 mA cm−2 with a stable and high Faradaic efficiency of 93 % for formate generation in a flow cell configuration. Electrochemical results demonstrate the synergistic effect in the Bi2O3@C promotes the rapid and selective CO2 reduction in which the Bi2O3 is beneficial for improving the reaction kinetics and formate selectivity, while the carbon matrix would be helpful for enhancing the activity and current density of formate production. This work provides effective bismuth-based MOF derivatives for efficient formate production and offers insights in promoting practical CO2 conversion technology. 相似文献
30.
Luocai Yi Dr. Junxiang Chen Ping Shao Dr. Junheng Huang Xinxin Peng Junwei Li Dr. Genxiang Wang Chi Zhang Prof. Zhenhai Wen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20287-20294
Two-dimensional (2D) monometallic pnictogens (antimony or Sb, and bismuth or Bi) nanosheets demonstrate potential in a variety of fields, including quantum devices, catalysis, biomedicine and energy, because of their unique physical, chemical, electronic and optical properties. However, the development of general and high-efficiency preparative routes toward high-quality pnictogen nanosheets is challenging. A general method involving a molten-salt-assisted aluminothermic reduction process is reported for the synthesis of Sb and Bi nanosheets in high yields (>90 %). Electrocatalytic CO2 reduction was investigated on the Bi nanosheets, and high catalytic selectively to formate was demonstrated with a considerable current density at a low overpotential and an impressive stability. Bi nanosheets continuously convert CO2 into formate in a flow cell operating for one month, with a yield rate of 787.5 mmol cm−2 h−1. Theoretical results suggest that the edge sites of Bi are far more active than the terrace sites. 相似文献