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   394篇
  免费   12篇
化学   295篇
晶体学   1篇
力学   27篇
数学   46篇
物理学   37篇
  2022年   4篇
  2021年   7篇
  2020年   4篇
  2019年   11篇
  2018年   9篇
  2017年   3篇
  2016年   15篇
  2015年   4篇
  2014年   9篇
  2013年   17篇
  2012年   16篇
  2011年   26篇
  2010年   17篇
  2009年   20篇
  2008年   26篇
  2007年   24篇
  2006年   17篇
  2005年   17篇
  2004年   18篇
  2003年   17篇
  2002年   10篇
  2001年   4篇
  2000年   7篇
  1999年   7篇
  1998年   4篇
  1997年   6篇
  1996年   8篇
  1995年   7篇
  1993年   4篇
  1992年   4篇
  1991年   5篇
  1989年   2篇
  1987年   1篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1983年   2篇
  1982年   3篇
  1981年   5篇
  1980年   7篇
  1979年   3篇
  1978年   5篇
  1977年   3篇
  1976年   1篇
  1975年   3篇
  1974年   9篇
  1973年   2篇
  1970年   1篇
  1967年   2篇
  1966年   1篇
排序方式: 共有406条查询结果,搜索用时 0 毫秒
81.
The HYDE scoring function consistently describes hydrogen bonding, the hydrophobic effect and desolvation. It relies on HYdration and DEsolvation terms which are calibrated using octanol/water partition coefficients of small molecules. We do not use affinity data for calibration, therefore HYDE is generally applicable to all protein targets. HYDE reflects the Gibbs free energy of binding while only considering the essential interactions of protein-ligand complexes. The greatest benefit of HYDE is that it yields a very intuitive atom-based score, which can be mapped onto the ligand and protein atoms. This allows the direct visualization of the score and consequently facilitates analysis of protein-ligand complexes during the lead optimization process. In this study, we validated our new scoring function by applying it in large-scale docking experiments. We could successfully predict the correct binding mode in 93% of complexes in redocking calculations on the Astex diverse set, while our performance in virtual screening experiments using the DUD dataset showed significant enrichment values with a mean AUC of 0.77 across all protein targets with little or no structural defects. As part of these studies, we also carried out a very detailed analysis of the data that revealed interesting pitfalls, which we highlight here and which should be addressed in future benchmark datasets.  相似文献   
82.
A geometric graph is a simple graph drawn on points in the plane, in general position, with straightline edges. A geometric homomorphism from to is a vertex map that preserves adjacencies and crossings. This work proves some basic properties of geometric homomorphisms and defines the geochromatic number as the minimum n so that there is a geometric homomorphism from to a geometric n‐clique. The geochromatic number is related to both the chromatic number and to the minimum number of plane layers of . By providing an infinite family of bipartite geometric graphs, each of which is constructed of two plane layers, which take on all possible values of geochromatic number, we show that these relationships do not determine the geochromatic number. This article also gives necessary (but not sufficient) and sufficient (but not necessary) conditions for a geometric graph to have geochromatic number at most four. As a corollary, we get precise criteria for a bipartite geometric graph to have geochromatic number at most four. This article also gives criteria for a geometric graph to be homomorphic to certain geometric realizations of K2, 2 and K3, 3. © 2011 Wiley Periodicals, Inc. J Graph Theory 69:97‐113, 2012  相似文献   
83.
IntroductionShakeflasksareusedroutinelyinthepharmaceu tical,biochemicalandmedicalfieldsforcellgrowthculture ,mediascreeningandforcellexpansion .Shakeflaskfermentationrequiresrelativelysmallamountsofmaterial,typicallybetween 5 0and 5 0 0mL ,andreliesonahorizon…  相似文献   
84.
Herein the first reported preparation of diblock copolymers of the polyethylene‐like polyester poly(ω‐pentadecalactone) (PPDL) via a combination of enzymatic ring‐opening polymerization (eROP) and reversible addition‐fragmentation chain‐transfer (RAFT) polymerization techniques is described. PPDL was synthesized via eROP using Novozyme 435 as a catalyst and a bifunctional initiator/chain transfer agent (CTA) appropriate for the eROP of ω‐pentadecalactone (PDL) and RAFT polymerization of acrylic and styrenic monomers. Chain growth of the PPDL macro‐CTA was performed to prepare acrylic and styrenic diblock copolymers of PPDL, and demonstrates a facile, metal‐free, and “greener” alternative to preparing acrylic diblock copolymers of polyethylene (PE). Diblock copolymer architecture was substantiated via analysis of 1H NMR spectroscopic, UV‐GPC chromatographic, DSC onset crystallization (Tc), and MALDI‐ToF mass spectrometric data. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3326–3335  相似文献   
85.
The shadowgraph method is used to visualize the convective flow in a water-filled square cavity, which is differentially heated and cooled from the opposing vertical sidewalls. Since in this system a quantitative recovery of the temperature field from the observed shadowgraph images is not possible, we apply a somewhat reverse procedure. The numerical solution of the cavity flow yields the field of the refractive index. By numerically integrating the path of light through this field, artificial shadowgraph images are constructed. This makes a comparison of the numerical and the experimental temperature fields possible and also leads to a clearer interpretation of the shadowgraph images and a better understanding of the way in which certain features are generated. The procedure is not restricted to the cavity flow, but can be applied whenever the field of the refractive index is available.  相似文献   
86.
87.
88.
We compare Higgs boson production mechanisms at multi-TeV hadronic colliders. In addition to the previously investigated processes gluon + gluon → H and qq → V1VH(V = W, Z), we consider Higgs boson formation by pairs of virtual W's or Z's, a process analogous to two-photon collisions in e+e? scattering. The Higgs production process W1W1H is dominated by longitudinal W's and is the most important mechanism for MH > 6 MW, if the top quark mass is about 30 GeV.  相似文献   
89.
90.
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