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   351篇
  免费   12篇
  国内免费   2篇
化学   166篇
晶体学   7篇
力学   13篇
数学   84篇
物理学   95篇
  2022年   4篇
  2020年   3篇
  2019年   6篇
  2018年   4篇
  2017年   8篇
  2016年   12篇
  2015年   7篇
  2014年   7篇
  2013年   20篇
  2012年   16篇
  2011年   14篇
  2010年   6篇
  2009年   5篇
  2008年   9篇
  2007年   16篇
  2006年   7篇
  2005年   5篇
  2004年   5篇
  2002年   4篇
  2001年   4篇
  2000年   10篇
  1999年   7篇
  1996年   7篇
  1995年   5篇
  1993年   8篇
  1992年   5篇
  1991年   3篇
  1990年   6篇
  1989年   6篇
  1988年   7篇
  1987年   4篇
  1986年   8篇
  1985年   8篇
  1984年   15篇
  1983年   5篇
  1982年   10篇
  1981年   7篇
  1979年   3篇
  1978年   3篇
  1977年   5篇
  1976年   3篇
  1975年   3篇
  1974年   6篇
  1973年   4篇
  1972年   5篇
  1966年   2篇
  1957年   2篇
  1956年   6篇
  1955年   4篇
  1936年   13篇
排序方式: 共有365条查询结果,搜索用时 15 毫秒
101.
The dielectric heating in quartz has been measured by the substitution method and its dependence on the nature of the liquid in which the crystal oscillates has been examined.  相似文献   
102.
A graph G is defined to be a unique eccentric point graph (a u.e.p. graph) if each point of G has a unique maximum distance point. Here u.e.p. graphs which are self-centered are characterized. Two construction procedures are given for generating families of u.e.p. graphs from known u.e.p. graphs. Furthermore, some special classes of u.e.p. graphs are studied in detail.  相似文献   
103.
104.
A model is proposed to explain the response time of solid-state membrane electrodes, in the range of potential—time curves corresponding to seconds or minutes. Several causes of slow response time are considered. In the range of milliseconds to seconds, diffusion seems to be the rate-determining factor, but for times exceeding about 10s, dissolution or crystallization and charge transfer at the membrane seem to be the predominant factors. A mathematical model is derived. The principle is applicable to any solid-state membrane electrode and takes into account the change in response time with changes in the nature or concentration of the test ion and in the surface electrochemical properties of the membrane.  相似文献   
105.
The optical diffraction set up as originally employed byDebye andSears andLucas andBiqdard has been used with various modifications to estimate the intensity of sound fields at two or more points along the axis of an ultrasonic beam travelling in a liquid and thereby to determine the absorption coefficient of the liquid medium. Almost all these methods involve a two step operation with the attendant possibility of errors due to variation in the conditions under which the two observations are made. In the method here reported two axially parallel beams of parallel monochromatic light are made to traverse the liquid normally to the direction of propagation of the sound beam and the resulting diffraction spectra are brought to focus on a common photographic plate. Sound intensities at two points separated by a known distance are thus measured simultaneously under identical conditions. Absorption coefficients calculated for half a dozen liquids by this method are reported. The values compare very favourably with those obtained by other precision methods.  相似文献   
106.
The probability distributions of the fractional intensities and amplitudes of x-ray reflections from a pair of imperfectly related structures are derived when both the structures satisfy the requirements of a given type of basic Wilson distribution. These two distributions are used to obtain theoretical expressions for 2 new fractional type ofR-indices which are expected to be useful in the final stages of refinement. The theoretical distributions are also used to deduce some theoretical distributions which are useful as tests for centrosymmetry via the random permutation method. The theoretical values of the relevant semi-cumulative functions are also tabulated.  相似文献   
107.
108.
In this paper, we consider the stochastic games ofShapley and prove under certain conditions the stochastic game has a value and both players have optimal strategies. We also prove a similar result for noncooperative stochastic games.  相似文献   
109.
110.
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