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   20465篇
  免费   156篇
  国内免费   89篇
化学   10461篇
晶体学   240篇
力学   601篇
综合类   7篇
数学   1717篇
物理学   7684篇
  2017年   155篇
  2016年   245篇
  2015年   167篇
  2014年   268篇
  2013年   845篇
  2012年   578篇
  2011年   641篇
  2010年   465篇
  2009年   474篇
  2008年   627篇
  2007年   682篇
  2006年   644篇
  2005年   584篇
  2004年   503篇
  2003年   478篇
  2002年   470篇
  2001年   696篇
  2000年   514篇
  1999年   430篇
  1998年   353篇
  1997年   339篇
  1996年   308篇
  1995年   381篇
  1994年   352篇
  1993年   325篇
  1992年   354篇
  1991年   395篇
  1990年   357篇
  1989年   351篇
  1988年   325篇
  1987年   320篇
  1986年   325篇
  1985年   398篇
  1984年   403篇
  1983年   297篇
  1982年   326篇
  1981年   347篇
  1980年   322篇
  1979年   324篇
  1978年   333篇
  1977年   316篇
  1976年   333篇
  1975年   286篇
  1974年   279篇
  1973年   300篇
  1972年   176篇
  1969年   162篇
  1968年   191篇
  1967年   335篇
  1966年   285篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
991.
We investigate the plasmonic response of gold nanospheres calculated using discrete dipole approximation validated against the results from other discretization methods, namely the finite-difference time-domain method and the finite-element methods. Comparisons are also made with calculations from analytical methods such as the Mie solution and the null-field method with discrete sources. We consider the nanoparticle interacting with the incident field both in free space and sitting on a planar substrate. In the latter case, discrete dipole approximation with surface interaction is used; this includes the interaction with the ‘image dipoles’ using Sommerfeld integration.  相似文献   
992.
ABSTRACT

RAPUNCL, a study course on Radionuclide Production with Cyclotrons, was organized in September 2017 in Mannheim. The intention was to test the feasibility of an educational program which is mainly driven by the input of the participating students. All aspects of target construction and operation have been covered in detail. Also the relevant aspects of Radiation Protection have been discussed. The students used intensively IAEA databases and MC simulation programs to model target design and operations. Topics for improvement have been identified and will be realized in the next course. Sources of funding have to be found to be able to organize the summer school in a sustainable way.  相似文献   
993.
We investigate the resonant production of color octet muons in order to explore the discovery potential of Future Circular Collider(FCC)-based μp colliders.It is shown that the search potentials of μp colliders essentially surpass the potential of the LHC and would exceed that of the FCC pp collider.  相似文献   
994.
995.
996.
The kinetics of the oxidative additions of haloheteroarenes HetX (X=I, Br, Cl) to [Pd0(PPh3)2] (generated from [Pd0(PPh3)4]) have been investigated in THF and DMF and the rate constants have been determined. In contrast to the generally accepted concerted mechanism, Hammett plots obtained for substituted 2‐halopyridines and solvent effects reveal a reaction mechanism dependent on the halide X of HetX: an unprecedented SNAr‐type mechanism for X=Br or Cl and a classical concerted mechanism for X=I. These results are supported by DFT studies.  相似文献   
997.
Physics of the Solid State - Electrodeposition of cobalt on monolayer graphene synthesized by chemical vapor deposition produces Co–CoO/graphene composite structures, which is accompanied by...  相似文献   
998.
999.
In this paper, we have obtained plane symmetric cosmological models of thick domain walls with viscous field coupled with electromagnetic field in the framework of Lyra geometry, by using equation of state. Physical and geometrical implications of the models are also discussed in the presence of magnetic field.  相似文献   
1000.
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