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   61篇
  免费   0篇
化学   11篇
数学   2篇
物理学   48篇
  2013年   3篇
  2012年   2篇
  2009年   1篇
  2008年   1篇
  2007年   2篇
  2002年   1篇
  2000年   4篇
  1999年   2篇
  1997年   1篇
  1996年   4篇
  1995年   7篇
  1994年   9篇
  1993年   6篇
  1992年   7篇
  1991年   1篇
  1990年   1篇
  1989年   1篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
  1981年   1篇
  1979年   2篇
  1978年   1篇
  1971年   1篇
排序方式: 共有61条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Poly(styrene-co-acrylamide) (PS-AAM) latex was prepared, fractionated by sedimentation under gravity, and characterized by PCS, infrared spectra, secondary and backscattered electron imaging in the scanning electron microscope, and electron spectroscopy imaging in an analytical transmission electron microscope. Three latex fractions were obtained. The lower fraction was opalescent and its particles were the more uniform, concerning size, chemical composition, and topochemical features. This lower fraction was still further fractionated by zonal centrifugation in a density gradient, yielding two fractions with similar macrocrystal-forming abilities but different sizes and chemical compositions. These results confirm those previously obtained for the PS-HEMA latex. Copyright 2000 Academic Press.  相似文献   
6.
7.
8.
9.
The potential of zero-angle depolarized scattering for measuring the size distributions of optically anisotropic particles is considered. To illustrate the method, an analysis of Fluon, a teflon latex suspension, is presented. Homodyne correlation functions having signal-to-noise characteristics every bit as good as conventional unpolarized finite-angle measurements enabled confident application of a smoothed exponential sampling algorithm to obtain the decay rate distribution, which was converted to a size distribution with certain approximations. The size distribution obtained from light scattering agrees well with that from electron microscopy.  相似文献   
10.
The superconducting transition temperature, Tc, of the LaT4P12 compounds with T = Fe, Ru, or Os has been measured under hydrostatic pressure P up to 1.8 GPa. The T = Fe compound exhibits a substantial increase of Tc from Tc (P = 0) = 4.1 K at a rate (dTc/dP)P=0= +7.2 x 10-1 K/GPa. In contrast, the Ru and Os compounds exhibit only weak decreases of Tc from Tc (P = 0) = 7.2 K and 1.8 K with (dTc/dP)P=0= -1.6 x 10-1 K/GPa and -9.5 x 10-2 K/GPa, respectively. An analysis of this strikingly divergent behavior of Tc(P) in terms of the structural characteristics of the RT4X12 class of compounds where R = rare earth element, T = Fe, Ru, or Os, and X = P, As, or Sb suggests that Tc(P) for these materials consists of two competing contributions: a depression of Tc due to the compression of the lattice (i.e., decrease in volume), and an enhancement of Tc due to the effect of pressure on La itself.  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