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   134篇
  免费   0篇
化学   22篇
晶体学   2篇
数学   38篇
物理学   72篇
  2023年   1篇
  2022年   4篇
  2021年   4篇
  2020年   3篇
  2019年   8篇
  2018年   3篇
  2017年   3篇
  2016年   8篇
  2015年   2篇
  2014年   7篇
  2013年   8篇
  2012年   4篇
  2011年   3篇
  2010年   7篇
  2008年   1篇
  2007年   4篇
  2006年   2篇
  2005年   4篇
  2004年   2篇
  2003年   2篇
  2002年   1篇
  2001年   5篇
  2000年   2篇
  1999年   3篇
  1998年   5篇
  1997年   8篇
  1996年   2篇
  1995年   2篇
  1993年   1篇
  1992年   2篇
  1991年   1篇
  1989年   3篇
  1987年   1篇
  1986年   2篇
  1985年   2篇
  1984年   1篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1979年   1篇
  1978年   2篇
  1977年   2篇
  1976年   1篇
  1975年   1篇
  1974年   2篇
排序方式: 共有134条查询结果,搜索用时 625 毫秒
1.
Results are presented that were obtained by measuring single-spin asymmetry in the inclusive production of neutral pions in the reaction p+p ↑→ π 0+X at x F≈0. A beam of 70-GeV protons was extracted directly from the vacuum chamber of the accelerator by means of a bent single crystal. For transverse momenta in the range 1.0<p T<3.0 GeV/c, the single-spin asymmetry independently measured by two detectors is zero within the errors. This result is in agreement with Fermilab data obtained at 200 GeV, but it is at odds with CERN data measured at 24 GeV.  相似文献   
2.
The relativistic correction to the triton binding energy approximated to the order (v/c)2 is calculated in the framework of relativistic Hamiltonian dynamics. We discuss the generator representation of the Poincaré group for three relativistic particles and its connection with the Feynman diagrams in the infinite-momentum frame (the light-front dynamics). The relativistic correction enhances the attraction in the three-nucleon system. The five-channel calculation with the Reid soft-core potential yeilds the result =–0.54 MeV, which is governed mainly by theD-wave contribution. TheS-wave contributions to are only –0.10 MeV.  相似文献   
3.
1,1- (AH) ([AH]=6,9 /, 50°C). AH Wi/WO 3=0,40±0,16.
The kinetics and oxidation products of 1,1-diethoxyethane (AH) ozonolysis have been investigated at [AH]=6.9 mol/l and 50 °C. The initiation efficiency of radical oxidation by ozone is Wi/WO 3=0.40±0.16.
  相似文献   
4.
5.
The enthalpy change of disproportionation reaction of nitroxyl and peroxyl radicals was calculated by the DFT B3LYP/cc-pVDZ method. The regeneration of the corresponding hydroxylamine during the oxidation of unsaturated compounds inhibited by nitroxyl radicals is shown to be associated with the disproportionation of the nitroxyl and peroxyl radicals.  相似文献   
6.
Crystallography Reports - Neutron diffraction studies on the small-angle neutron spectrometer YuMO (Joint Institute for Nuclear Research, Dubna), based on the IBR-2 pulsed reactor, have been...  相似文献   
7.
8.
The level density for doubly odd deformed nuclei near Bn is calculated within the framework of the semi-microscopic approach. The calculated values are found to be in good agreement with the experimental ones. It is shown that for the I ? 1 states it is important to take into account rotational motion.  相似文献   
9.
The atomic layer deposition of titanium oxide in the precursor systems Ti(OCH3)4-H2O and Ti(OC2H5)4-H2O was compared. The growth rate of titanium oxide formed by the atomic layer deposition in the Ti(OCH3)4-H2O system can be adequately estimated with due to regard for the number and size of ligands of a metal-containing precursor. The study in simulated body fluid solutions showed that polycrystallin TiO2 coatings with anatase structure are prone to accelerated osseointegration and, consequently, promising for the development of new biomedical products.  相似文献   
10.
Nickel-alumina catalysts supported on cordierite monoliths of honeycomb structure surpass essentially the conventional granulated ones with respect to the output in carbon dioxide reforming of methane. Adjusting the surface acid-base properties of catalysts by introduction of alkali metal (Na, K) oxides inhibits the carbonization and as a result, improves the operational stability of these catalysts. An effect of promotion of nickel-alumina based composite doped by lanthanum oxide is found. This effect, caused by an additional route for the CO2 activation on Ni-La2O3/Al2O3/cordierite catalyst, is displayed in increase of methane conversion under conditions of an oxidant excess.  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