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   114篇
  免费   0篇
化学   51篇
晶体学   5篇
数学   14篇
物理学   44篇
  2022年   1篇
  2021年   1篇
  2020年   1篇
  2019年   1篇
  2018年   1篇
  2017年   1篇
  2016年   3篇
  2015年   2篇
  2014年   3篇
  2013年   3篇
  2012年   7篇
  2011年   4篇
  2010年   11篇
  2009年   7篇
  2008年   4篇
  2007年   11篇
  2006年   6篇
  2005年   3篇
  2004年   5篇
  2003年   3篇
  2002年   4篇
  2001年   2篇
  2000年   2篇
  1999年   2篇
  1998年   2篇
  1997年   2篇
  1996年   1篇
  1995年   2篇
  1994年   2篇
  1993年   3篇
  1992年   2篇
  1991年   3篇
  1990年   4篇
  1987年   2篇
  1986年   1篇
  1984年   1篇
  1969年   1篇
排序方式: 共有114条查询结果,搜索用时 0 毫秒
31.
32.
T.Sheil-Small[1]讨论了阶梯函数的Fourier级数。本文对[1]中所涉及到一些阶梯函数的性质进行了详细讨论,并给出了详细证明。  相似文献   
33.
34.
35.
Biomorphic zirconia fibers were prepared by successive carbonization and/or calcining of sawdust impregnated by a solution of zirconium oxynitrate. Pyrolysis was performed in nitrogen (500°C), and calcining, in air (600°C). The physicochemical characteristics of samples were studied by adsorption measurements, electron microscopy, and X-ray diffraction. The biomorphic fibers were composed of zirconia nanoparticles not larger than 12 nm. The samples had a uniform phase composition dominated by the tetragonal ZrO2 phase; their specific surface area was 13–38 m2/g depending on the salt content in sawdust. It was assumed that the stabilization of the tetragonal phase could be related to the incorporation of mineral components (calcium, magnesium, and potassium compounds) of sawdust into zirconia; carbonization had no substantial effect on the properties of the resulting oxide. The method developed could be used to obtain tetragonal zirconia (without expensive reagents and water consumption) and utilize wood industry wastes.  相似文献   
36.
The structure of the first excited electronic states of indole has been calculated for the isolated state and aqueous solution. The vibrational spectra of isolated indole have been calculated by the DFT method in the harmonic and anharmonic approximations. The resonance Raman spectra of indole have been calculated quantum mechanically in the Herzberg-Teller approximation. The effect of hydrogen bonds on the structure and vibrational (Raman and resonance Raman) spectra of indole has been analyzed.  相似文献   
37.
The method of quantum-mechanical calculation of the relative line intensities in the resonance Raman (RR) spectra of polyatomic molecules, which was previously applied to the analysis of the spectra of individual cyclic molecules and makes it possible to take into account the Herzberg-Teller and Duschinsky effects, as well as the frequency effect, is applied for the first time to the calculation of the spectra of a pair guanine-cytosine. Satisfactory agreement between the calculated results and the available experimental data is obtained. The particular features of the intensity distribution in the RR spectra of the guanine-cytosine pair excited by laser radiation at 266, 240, 218, and 200 nm are analyzed. The RR spectra of the guanine-cytosine pair are compared with the spectra of the individual guanine and cytosine molecules excited by the laser radiation at the same wavelengths.  相似文献   
38.
39.
Moscow University Chemistry Bulletin - Abstract—Molecular heterogeneity in seven human metastatic melanoma cells lines is revealed using a double immunofluorescent assay by flow cytometry. It...  相似文献   
40.
该文研究极限方程在部分边界上为退缩椭圆型(椭圆-抛物)的一类六阶椭圆型方程混合边值问题的奇摄动,在适当的假设下,应用改进了的多重尺度法,求得其解包括边界层和套层在内除了半圆域的两个角点外,在整个半圆域中有任意阶的一致有效的渐近展开式.  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