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   689篇
  免费   14篇
  国内免费   2篇
化学   563篇
晶体学   6篇
力学   14篇
数学   48篇
物理学   74篇
  2021年   5篇
  2019年   5篇
  2016年   13篇
  2015年   12篇
  2014年   4篇
  2013年   38篇
  2012年   27篇
  2011年   36篇
  2010年   7篇
  2009年   16篇
  2008年   29篇
  2007年   20篇
  2006年   34篇
  2005年   31篇
  2004年   31篇
  2003年   25篇
  2002年   32篇
  2001年   17篇
  2000年   4篇
  1999年   12篇
  1998年   14篇
  1997年   5篇
  1996年   7篇
  1995年   5篇
  1994年   5篇
  1993年   7篇
  1992年   8篇
  1991年   8篇
  1990年   6篇
  1989年   8篇
  1988年   6篇
  1987年   6篇
  1986年   12篇
  1985年   17篇
  1984年   16篇
  1983年   6篇
  1982年   24篇
  1981年   17篇
  1980年   14篇
  1979年   17篇
  1978年   16篇
  1977年   15篇
  1976年   5篇
  1975年   9篇
  1974年   11篇
  1973年   5篇
  1972年   6篇
  1971年   4篇
  1968年   3篇
  1967年   3篇
排序方式: 共有705条查询结果,搜索用时 15 毫秒
1.
Imanishi  Hinano  Nishimura  Takahiro  Awazu  Kunio 《Optical Review》2022,29(4):310-319
Optical Review - This paper demonstrates a method to estimate the depth of a fluorescence object in turbid media using dual-wavelength excited photodynamic diagnosis, to aid in the invasion depth...  相似文献   
2.
Infection of hosts by morbilliviruses is facilitated by the interaction between viral hemagglutinin (H-protein) and the signaling lymphocytic activation molecule (SLAM). Recently, the functional importance of the n-terminal region of human SLAM as a measles virus receptor was demonstrated. However, the functional roles of this region in the infection process by other morbilliviruses and host range determination remain unknown, partly because this region is highly flexible, which has hampered accurate structure determination of this region by X-ray crystallography. In this study, we analyzed the interaction between the H-protein from canine distemper virus (CDV-H) and SLAMs by a computational chemistry approach. Molecular dynamics simulations and fragment molecular orbital analysis demonstrated that the unique His28 in the N-terminal region of SLAM from Macaca is a key determinant that enables the formation of a stable interaction with CDV-H, providing a basis for CDV infection in Macaca. The computational chemistry approach presented should enable the determination of molecular interactions involving regions of proteins that are difficult to predict from crystal structures because of their high flexibility.  相似文献   
3.
Cellulose derivative resin (CDR) suspensions containing resin particles of cellulose nitrate (CDR(CN)), cellulose acetate (CDR(CA)), or cellulose triacetate (CDR(CTA)) were prepared as the sorbent for resin suspension injection (RSI) electrothermal atomic absorption spectrometry (ETAAS), in which fine resin particles holding a desired trace element were directly injected into the graphite tube as the suspension. To compare the sorption ability, the distribution ratios of the Mo(VI)-phenylfluorone complex were measured between the aqueous phase and the sorbents, including the CDRs mentioned above and the finely divided anion exchange resin (AR). The results showed that the sorption ability decreases in the following order: CDR(CN) > or = AR > CDR(CA) > or = CDR(CTA). It was concluded that CDR(CN) was able to extract more than 98% of Mo(VI), and was suitable for RSI-ETAAS as well as AR. CDR(CN) was used for the determination of Mo in NIES certified reference materials, No. 10 Rice flour-unpolished; the results showed fairly good agreements between the analytical values and the certified values.  相似文献   
4.
An InGaAs/InAlAs five-layer asymmetric coupled quantum well (FACQW) is expected to show very large electrorefractive index change. n in a wideband transparency region. Band structures of the FACQW are analyzed with Luttinger-Kohn Hamiltonian. The electrorefractive characteristics of the FACQW are discussed.  相似文献   
5.
13C NMR studies showed that the population of the norcaradiene form of the title systems containing p-CH3O, H, and p-CF3 on the 7-aryl group increases in this order. The result is consistent with the prediction from the π-acceptor strength of the aryl group estimated by INDO calculations.  相似文献   
6.
7.
We prove that a large class of self-injective algebras of tilted type is invariant under stable equivalences of module categories.

  相似文献   

8.
9.
10.
Summary Vacuum Fusion Determination of Micro-quantities of Bulk Gases in Low Carbon Iron Without an Effect of Surface Gases Micro-quantities of bulk and surface oxygen and hydrogen in low carbon iron was simultaneously determined by the surface-area-variation method using vacuum fusion analysis. Among the difference of three surface treatments, silicon carbide abrasive, electropolishing and hydrogen reduction methods, bulk oxygen and hydrogen were in agreement within their errors, however, surface oxygen and hydrogen were influenced from the surface treatments. Even in the case of electropolishing, which gave the smallest surface oxygen value, bulk oxygen less than 10g/g is needed to discriminate from the surface oxygen. Bulk hydrogen of 0.03g/g was determined without the effect of surface hydrogen in the hydrogen reduction treatment.  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