首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   199篇
  免费   12篇
  国内免费   5篇
化学   174篇
晶体学   2篇
力学   7篇
数学   11篇
物理学   22篇
  2024年   1篇
  2023年   1篇
  2022年   7篇
  2021年   9篇
  2020年   11篇
  2019年   21篇
  2018年   15篇
  2017年   11篇
  2016年   15篇
  2015年   7篇
  2014年   19篇
  2013年   14篇
  2012年   21篇
  2011年   13篇
  2010年   7篇
  2009年   12篇
  2008年   6篇
  2007年   10篇
  2006年   5篇
  2005年   2篇
  2004年   2篇
  2003年   1篇
  2002年   2篇
  2000年   1篇
  1995年   1篇
  1986年   1篇
  1981年   1篇
排序方式: 共有216条查询结果,搜索用时 250 毫秒
1.
2.
The complex of propyltriphenylphosphonium bromochromate(VI), PrPh3P[CrO3Br] is easily synthesized in nearly quantitative yield using a direct reaction of chromium(VI) oxide and propyltriphenylphosphonium bromide. This compound is a versatile reagent for the efficient and selective oxidation of organic substrates, in particular for alcohols to their corresponding aldehydes or ketones, under mild conditions. This compound was characterized by IR, UV/Visible, 13C-n.m.r. and 1H-n.m.r. techniques. It crystallized in the monoclinic form and its crystal and molecular structure have been determined by X-ray crystallography.  相似文献   
3.
An environmentally benign aqueous protocol for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones and thiones promoted by a green catalyst,silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate,has been developed.The use of nontoxic,thermally stable and inexpensive amino acid catalyst makes the process simple with minimal amount of chemical waste.Compared with classical Biginelli reaction conditions,this new method has the advantages of high yields and simple workup procedures.  相似文献   
4.
5.
Research on Chemical Intermediates - A dual-functional silica-based catalyst was prepared by treating fumed silica with amino-containing silane then 1,4-butane sultone. The presence of functional...  相似文献   
6.
7.
Journal of the Iranian Chemical Society - Herein, we investigated the interaction of cisplatin loaded on GO (GO@CDDP) with two regulatory sequences, BRCA1 and BRCA2, synthesized from ssDNA based on...  相似文献   
8.
A four‐component reaction between aromatic carboxylic acids, (N‐isocyanimino)triphenylphosphorane, ferrocenecarbaldehyde and dibenzylamine is reported. This approach is an efficient, simple and high‐yield procedure for the synthesis of 1,3,4‐oxadiazole derivatives containing a ferrocene unit. The antimicrobial activities of the products were investigated against Staphylococcus aureus and Pseudomonas aeruginosa in in vitro and in vivo assays. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
9.
Research on Chemical Intermediates - A convenient, rapid, and highly efficient procedure for synthesis of 5-substituted-1H-tetrazoles was developed via multicomponent domino Knoevenagel...  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号