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   643篇
  免费   28篇
  国内免费   3篇
化学   399篇
晶体学   3篇
力学   25篇
数学   91篇
物理学   156篇
  2023年   8篇
  2022年   14篇
  2021年   12篇
  2020年   12篇
  2019年   10篇
  2018年   11篇
  2017年   3篇
  2016年   24篇
  2015年   24篇
  2014年   23篇
  2013年   39篇
  2012年   34篇
  2011年   55篇
  2010年   32篇
  2009年   46篇
  2008年   45篇
  2007年   42篇
  2006年   40篇
  2005年   35篇
  2004年   27篇
  2003年   20篇
  2002年   17篇
  2001年   8篇
  2000年   6篇
  1999年   6篇
  1998年   7篇
  1997年   9篇
  1996年   4篇
  1995年   5篇
  1994年   4篇
  1993年   4篇
  1992年   6篇
  1991年   1篇
  1990年   2篇
  1989年   5篇
  1988年   3篇
  1987年   3篇
  1986年   5篇
  1985年   4篇
  1984年   5篇
  1983年   3篇
  1982年   2篇
  1980年   1篇
  1979年   2篇
  1977年   1篇
  1975年   1篇
  1972年   1篇
  1938年   1篇
  1926年   2篇
排序方式: 共有674条查询结果,搜索用时 15 毫秒
151.
In this article we use the concept of r-depth to introduce the notion of dual multilinearity index. Using this concept we associate to each irreducible character of a subgroup G of Sm an improper partition of m. It is proved that of G = Sm this partition is the partition usually associated to the irreducible characters of Sm.  相似文献   
152.
In the calcium atom, the MCHF method has been applied for evaluating the field-shift electronic parts of both 4s 2-4s4p lines, and the hyperfine-structure electronic effective parameters of the 4s4p 3 P 2 and1 P 1 levels. For the hyperfine structures, the far-configuration mixing corrections have been computed with the assumption that the lower state is itself a two-componentsp+dp state in close-configuration mixing.  相似文献   
153.
154.
155.
Abstract

Two copper(II) complexes with tetradentate 1,4-disubstituted-1,2,3-triazole ligands, [CuL(MeCN)](ClO4)2 (1) and [CuL′](ClO4)2 (2), have been prepared and characterized by different techniques, including X-ray structure determination, spectroscopic, and electrochemical measurements, as reported elsewhere. Herein, we report the interactions of these complexes, and corresponding free ligands, with human serum albumin (HSA) verifying their relative thermodynamic stability and differences in binding to this protein. Interactions with HSA were verified by CD measurements monitored at 564?nm, up to stoichiometric ratio 2:1 [Complex]:[protein], according to competitive equilibria involving the insertion of copper at the selective N-terminal metal binding site in HSA, and additionally at a secondary nonselective site. Further interactions of these complexes with L-tryptophan residues, and probable supplementary site(s) for the binding, were followed by fluorescence measurements. Analogous experiments with the free L and L′ indicated much weaker interactions. Protein oxidation damage was observed for both complexes, monitored by carbonyl groups formation in the presence of H2O2, probably with the participation of reactive oxygen species. Density functional theory calculations exhibit metal-ligand binding interaction energies similar to [Cu(HSA-Nterminal)]+, and reinforced the experimental results, showing clearly that such triazole ligands are competitive toward copper(II) in biological medium.  相似文献   
156.
Journal of Solid State Electrochemistry - Thymol, a potent agent for microbial, fungal, and bacterial disease, has low aqueous solubility and it is genotoxic, i.e., is capable of damaging...  相似文献   
157.
158.
A preliminary estimate of the three-nucleon force within the adiabatic framework has already been done. In this work we try to improve the first calculation by using relativistic kinematics for the pion and including theP 11 absorption channel, as well as theP 33 and the less importantS 13,S 11,P 13,P 31 channels, in theN interaction.Presented at the symposium Mesons and Light Nuclei, Bechyn, Czechoslovakia. May 27–June 1, 1985.  相似文献   
159.
Solid adducts SbX3·L-pic (X=Cl, I and L=α-, β- and γ-picolines) were synthesized and characterized by elemental analysis, 1H and 13C NMR, IR spectroscopy and thermal analysis. The infrared spectroscopy and the magnetic resonance for 1H and 13C nuclei of these compounds suggest that the ligands coordinate through nitrogen atom. Kinetic studies were accomplished by means of thermogravimetric data, through isothermal and non-isothermal techniques. The best adjusting models for adducts thermal decomposition were R1 for isothermal and R1 and R2 for the non-isothermal methods. The energy of activation values obtained by isothermal method indicate the following orders of thermal stability for adducts: i) SbCl3·α-pic>SbCl3·β-pic>SbCl3·γ-pic and ii) SbI3·β-pic>SbI3·γ-pic>SbI3·α-pic. The activation energy values obtained by non-isothermal were higher than those from isothermal methods, showing the order of stability:iii) SbCl3·α-pic<SbCl3·β-pic<SbCl3·γ-pic and iv) SbI3·β-pic>SbI3·α-pic=SbI·γ-pic. These obtained data through R1 model presented the kinetic compensation effect for trichloride adducts, which could be associated to both isothermal and non-isothermal processes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
160.
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