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   299篇
  免费   0篇
化学   212篇
晶体学   1篇
力学   1篇
数学   5篇
物理学   80篇
  2019年   3篇
  2016年   5篇
  2015年   2篇
  2014年   3篇
  2013年   12篇
  2012年   16篇
  2011年   15篇
  2010年   6篇
  2009年   3篇
  2008年   18篇
  2007年   23篇
  2006年   23篇
  2005年   7篇
  2004年   11篇
  2003年   10篇
  2002年   8篇
  2001年   9篇
  2000年   4篇
  1999年   5篇
  1998年   2篇
  1997年   3篇
  1996年   8篇
  1995年   12篇
  1994年   13篇
  1993年   7篇
  1992年   8篇
  1991年   4篇
  1990年   5篇
  1989年   1篇
  1988年   3篇
  1987年   4篇
  1986年   1篇
  1985年   4篇
  1984年   4篇
  1983年   1篇
  1982年   2篇
  1981年   2篇
  1980年   3篇
  1979年   3篇
  1978年   1篇
  1977年   3篇
  1976年   1篇
  1975年   1篇
  1974年   3篇
  1973年   4篇
  1972年   5篇
  1971年   3篇
  1969年   1篇
  1965年   1篇
  1918年   1篇
排序方式: 共有299条查询结果,搜索用时 15 毫秒
111.
112.
113.
New high-resolution Fourier transform absorption spectra of an (15)N(16)O(2) isotopic sample of nitrogen dioxide were recorded at the University of Bremen in the 6.3-μm region. Starting from the results of a previous study [Y. Hamada, J. Mol. Struct. 242, 367-377 (1991)], a new and more extended analysis of the nu(3) band located at 1582.1039 cm(-1) has been performed. The spin-rotation energy levels were satisfactorily reproduced using a theoretical model which takes into account both the Coriolis interactions between the spin-rotation energy levels of the (001) vibrational state with those of the (020) and (100) states and the spin-rotation resonances within each of the NO(2) vibrational states. Precise vibrational energies and rotational, spin-rotation, and coupling constants were obtained in this way for the first triad of (15)N(16)O(2) interacting states {(020), (100), (001)}. Finally, a comprehensive list of line positions and line intensities of the {nu(1), 2nu(2), nu(3)} interacting bands of (15)N(16)O(2) was generated, using for the line intensities the transition moment operators which were obtained previously for the main isotopic species. Copyright 2000 Academic Press.  相似文献   
114.
Electrophysiological evidence for the critical band phenomenon in humans using event-related potentials has been sought for many years with conflicting results. Components Na and Pa of the middle-latency response (MLR) and wave V of the auditory brain-stem response (ABR) were simultaneously recorded in response to a two-tone complex varying in bandwidth from 76 Hz to 1012 Hz, centered at 2 kHz, and presented at an overall level of 85 dB SPL, in ten normal female subjects. Only the amplitude of Na showed an abrupt increase as bandwidth changed from 268 to 330 Hz, yielding an estimate of critical bandwidth in good agreement with previous behavioral estimates.  相似文献   
115.
Two of the perturbation methods developed in Paper I (CIPT and SCPT) are extended for use with uncoupled Hartree-Fock perturbation theory. Corrections to the uncoupled results are discussed and it is found that it is possible to correct using functions which when applied to ground state calculations are equivalent to the geometric approximation. It is also shown that CIPT and SCPT can be applied to ground state calculations and that when coupled perturbed orbitals are used CIPT and SCPT are equivalent to the usual coupled perturbation theory.  相似文献   
116.
A facile in situ nanoparticle seeding method is reported to prepare MIL-101(Cr) films on alumina supports. The in situ seeding of MIL-101(Cr) nanoparticles was promoted by use of dimethylacetamide (DMA). The generality of this approach is further demonstrated for Cu(3)(btc)(2) films by using a (poly)acrylate promoter.  相似文献   
117.
118.
A brief overview is given of the theory of surface-ion neutralization (SIN) by highlighting studies from the pioneering days to the present time. Emphasis is placed on the 1-electron time-dependent Newns-Anderson (TDNA) model, which has played such a key role in studying resonance charge transfer. Recently, a many-electron (ME) version of the TDNA approach has been formulated to treat two or more electron processes, such as Auger transitions. The equation-of-motion technique is used to obtain the TD coefficients from which the required SIN probabilities can be found. After outlining the ME method, two applications are described. The first deals with the Li+-Cs/W(110) system, while the second addresses the laser enhancement of SIN, in the case of Li+-KBr, and revises some earlier results.  相似文献   
119.
120.
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