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   301篇
  免费   3篇
化学   53篇
力学   20篇
综合类   1篇
数学   83篇
物理学   147篇
  2021年   3篇
  2020年   9篇
  2019年   5篇
  2018年   3篇
  2017年   7篇
  2016年   6篇
  2014年   7篇
  2013年   10篇
  2012年   12篇
  2011年   7篇
  2010年   10篇
  2009年   10篇
  2008年   9篇
  2007年   6篇
  2006年   8篇
  2005年   6篇
  2004年   8篇
  2003年   5篇
  2002年   10篇
  2001年   6篇
  2000年   8篇
  1999年   9篇
  1997年   6篇
  1996年   6篇
  1995年   2篇
  1994年   6篇
  1993年   5篇
  1992年   3篇
  1991年   3篇
  1990年   8篇
  1989年   8篇
  1988年   6篇
  1987年   2篇
  1986年   11篇
  1984年   4篇
  1983年   5篇
  1982年   3篇
  1981年   5篇
  1980年   3篇
  1979年   3篇
  1978年   4篇
  1976年   5篇
  1975年   5篇
  1974年   3篇
  1972年   3篇
  1971年   6篇
  1970年   5篇
  1969年   4篇
  1968年   5篇
  1967年   2篇
排序方式: 共有304条查询结果,搜索用时 93 毫秒
51.
The hierarchy of gauge interactions within the E6 model is proved, and the vector and spinor field masses are obtained. The mass spectrum of the charged W-bosons is found, and the mass scale is fixed so that the mass of the lightest of them is about 70 GeV. The lepton spectroscopy is studied and a new charged lepton, with mass of order 4–8 GeV is predicted. For the low-energy phenomenology, the model may be considered as a theory of 6 flavoured quarks and 4 charged leptons, each with its neutrino. Being 4-component the neutrinos are massive except for the νe (mνe = 0, exactly) and νμ (mνμ ≈ 0, approximately) particles. The problem of the “superfluous” particles which as a rule accompanies the asymptotic freedom in such theories is also briefly discussed.  相似文献   
52.
53.
54.
55.
Starting from the extended tree-level model for the πN interaction [1] (hereafter ETLM) we demonstrated that the observed local pion-nucleus repulsion arises from the reduction of baryon masses in nucleus due to strong scalar nuclear field [2]. This is rather convincing argument in favour of nuclear relativism because such repulsion has no explanation within the traditional nonrelativistic approach to nucleus.  相似文献   
56.
57.
The motion of a helium atom through the quartz crystal structure disturbed by dislocations has been considered. Two cases of their action on the motion of the helium atom have been discussed. (1) Dislocations, in particular, screw dislocations, can be represented as contracted or extended helical (six-, four-, three-membered) channels consisting of SiO4 tetrahedra. In this case, the helium atom moves inside the dislocation as in the crystallographic channel with changed parameters. (2) Dislocations can cross the crystallographic channel. This leads to an excess or a deficit of oxygen atoms of SiO4 tetrahedra in the immediate environment of the helium atom located in the channel. In both cases, the displacement of the helium atom appears as a Frenkel-Kontorova soliton. However, in the latter case, the dependence of the activation energy of this soliton on the number of defects is discontinuous and exhibits a “mobility gap” of the helium atom.  相似文献   
58.
In infinite-dimensional Hilbert spaces, we prove that the iterative sequence generated by the extragradient method for solving pseudo-monotone variational inequalities converges weakly to a solution. A class of pseudo-monotone variational inequalities is considered to illustrate the convergent behavior. The result obtained in this note extends some recent results in the literature; especially, it gives a positive answer to a question raised in Khanh (Acta Math Vietnam 41:251–263, 2016).  相似文献   
59.
Light scattered from biological tissues can exhibit an inverse power law spectral component. We develop a model based on the Born approximation and von Karman (self-affine) spatial correlation of submicron tissue refractive index to account for this. The model is applied to light scattering spectra obtained from excised esophagi of normal and carcinogen-treated rats. Power law exponents used to fit dysplastic tissue site spectra are significantly smaller than those from normal sites, indicating that changes in tissue self-affinity can serve as a potential biomarker for precancer.  相似文献   
60.
Russian Physics Journal - Magnetron sputtering, vacuum arc deposition, and ion implantation have been used to create a three-layer anti-corrosive coating structure on stainless steel samples. The...  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