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   89篇
  免费   1篇
  国内免费   3篇
化学   16篇
物理学   77篇
  2022年   1篇
  2021年   2篇
  2020年   2篇
  2018年   1篇
  2016年   1篇
  2014年   1篇
  2013年   2篇
  2012年   3篇
  2011年   2篇
  2010年   2篇
  2009年   5篇
  2008年   2篇
  2007年   2篇
  2006年   6篇
  2005年   4篇
  2004年   1篇
  2003年   4篇
  2002年   2篇
  2001年   2篇
  2000年   2篇
  1999年   1篇
  1996年   4篇
  1995年   2篇
  1994年   3篇
  1992年   4篇
  1991年   3篇
  1990年   4篇
  1989年   2篇
  1988年   2篇
  1987年   4篇
  1986年   2篇
  1985年   5篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
  1977年   2篇
  1976年   3篇
  1975年   1篇
  1970年   1篇
排序方式: 共有93条查询结果,搜索用时 15 毫秒
61.
We motivate and construct supersymmetric theories with continuous flavor symmetry, under which the electroweak Higgs doublets transform non-trivially. Flavor symmetry is spontaneously broken at a large mass scale in a sector of gauge-singlet fields; the light Higgs multiplets naturally emerge as special linear combinations that avoid acquiring the generic large mass. Couplings of the light Higgs doublets to light moduli fields from the singlet sector could lead to important effects in the phenomenology of the Higgs sector.  相似文献   
62.
63.
Neutrino-induced trimuon events have been interpreted by several authors as arising from cascade decay of a new lepton produced directly in neutrino reactions. We incorporate this idea in a gauge scheme based on the group Su(2) × SU(2) × U(1).  相似文献   
64.
The fact that SU(2) allows inequivalent embeddings inside larger groups is shown to have some consequences for the interaction of instantons.  相似文献   
65.
66.
The Pictet-Spengler reaction of Trp with α-amino aldehydes derived from l and d-amino acids was studied in terms of double stereodifferentiation. The results observed for d-amino aldehydes represent ‘matched’ situation (one diastereoisomer was formed) whereas with l-amino aldehydes ‘mismatched’ (two diastereoisomers were formed). The conformation of newly formed six-membered ring was analyzed. It was found that stable conformers were different for cis and trans isomers.  相似文献   
67.
Two sets of phenomena peculiar to non-Abelian gauge theories are illustrated. The first concerns the existence of nonsingular potentials which generate the same field strength without being gauge-equivalent; a necessary condition for this ambiguity is obtained. The second exhibits the insufficiency of the cyclic identity in determining field strength-potential relations.  相似文献   
68.
Elementary examples are provided of reaction rate matrices satisfying the constraints of unitarity and CPT invariance, which can lead a system with baryon number initially zero to evolve toward non-zero baryon number. The importance of the unitarity constraint is emphasized.  相似文献   
69.
    
Combining three features—the high affinity of squaramides toward anions, cooperation in ion pair binding and preorganization of the binding domains in the tripodal platform—led to the effective receptor 2. The lack of at least one of these key elements in the structures of reference receptors 3 and 4 caused a lower affinity towards ion pairs. Receptor 2 was found to form an intramolecular network in wet chloroform, which changed into inorganic–organic associates after contact with ions and allowed salts to be extracted from an aqueous to an organic phase. The disparity in the binding mode of 2 with sulfates and with other monovalent anions led to the selective extraction of extremely hydrated sulfate anions in the presence of more lipophilic salts, thus overcoming the Hofmeister series.  相似文献   
70.
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