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   27篇
  免费   2篇
化学   6篇
数学   2篇
物理学   21篇
  2019年   1篇
  2018年   5篇
  2017年   5篇
  2015年   6篇
  2014年   3篇
  2013年   3篇
  2011年   2篇
  2000年   2篇
  1983年   2篇
排序方式: 共有29条查询结果,搜索用时 640 毫秒
1.
2.
The foundations of quantum theory can be understood as a consequence of a fundamental concept of identity. Intuitive arguments motivate a mathematical formulation of identicality (the indistinguishability and equality of identical particles). Using a theorem of Fivel, this form of identicality leads to standard quantum theory.  相似文献   
3.
The peptide antibiotic albicidin, which is synthesized by the plant pathogenic bacterium Xanthomonas albilineans, displays remarkable antibacterial activity against various Gram‐positive and Gram‐negative microorganisms. The low amounts of albicidin obtainable from the producing organism or through heterologous expression are limiting factors in providing sufficient material for bioactivity profiling and structure–activity studies. Therefore, we developed a convergent total synthesis route toward albicidin. The unexpectedly difficult formation of amide bonds between the aromatic amino acids was achieved through a triphosgene‐mediated coupling strategy. The herein presented synthesis of albicidin confirms the previously determined chemical structure and underlines the extraordinary antibacterial activity of this compound. The synthetic protocol will provide multigram amounts of albicidin for further profiling of its drug properties.  相似文献   
4.
5.
6.
Physics of Particles and Nuclei Letters - The problems of the metrological certification of beams of high-energy heavy charged particles (HCPs) and protons that will be used in the study—as...  相似文献   
7.
Oxidation chemistry using enzymes is approaching maturity and practical applicability in organic synthesis. Oxidoreductases (enzymes catalysing redox reactions) enable chemists to perform highly selective and efficient transformations ranging from simple alcohol oxidations to stereoselective halogenations of non‐activated C?H bonds. For many of these reactions, no “classical” chemical counterpart is known. Hence oxidoreductases open up shorter synthesis routes based on a more direct access to the target products. The generally very mild reaction conditions may also reduce the environmental impact of biocatalytic reactions compared to classical counterparts. In this Review, we critically summarise the most important recent developments in the field of biocatalytic oxidation chemistry and identify the most pressing bottlenecks as well as promising solutions.  相似文献   
8.
9.
10.
The emission spectrum of the d3Πg-a3Πu system (Swan bands) due to 13C2 and 12C13C molecules has been obtained in a low pressure hollow cathode discharge through a mixture of argon and benzene containing enriched 13C (90%). The spectrum was photographed on a 3.4-m Ebert spectrograph (reciprocal dispersion 0.54 Å mm−1 in the first order). Isotope effect measurements have been carried out to determine the shift between isotopic bands and those emitted by ordinary molecules. The rotational analysis of six 13C2 bands and three bands of 12C13C has been performed and molecular constants were derived.  相似文献   
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