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   125篇
  免费   2篇
  国内免费   1篇
化学   40篇
力学   2篇
数学   4篇
物理学   82篇
  2022年   1篇
  2019年   2篇
  2017年   2篇
  2015年   3篇
  2013年   9篇
  2012年   2篇
  2011年   2篇
  2010年   4篇
  2009年   1篇
  2008年   6篇
  2007年   7篇
  2006年   3篇
  2004年   4篇
  2003年   5篇
  2002年   4篇
  2001年   8篇
  2000年   2篇
  1999年   1篇
  1997年   2篇
  1996年   1篇
  1995年   3篇
  1994年   2篇
  1992年   3篇
  1990年   8篇
  1989年   1篇
  1988年   3篇
  1987年   3篇
  1985年   4篇
  1984年   2篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1980年   1篇
  1979年   4篇
  1978年   1篇
  1977年   3篇
  1976年   5篇
  1975年   2篇
  1974年   3篇
  1973年   3篇
  1972年   1篇
  1971年   1篇
  1966年   1篇
  1965年   1篇
排序方式: 共有128条查询结果,搜索用时 31 毫秒
1.
Two new hereditary classes of P5-free graphs where the stability number can be found in polynomial time are proposed. They generalize several known results.  相似文献   
2.
3.
4.
5.
The first experimental evidence is reported of crystallization induced in an amorphous alloy by a high density of electronic excitation deposited along the path of swift heavy ions. The formation of nanocrystalline iron boride phases was observed in an amorphous Fe73.5Cu1Nb3Si13.5B9 alloy irradiated at low temperature with 5 GeV Pb ions up to fluences of 1 x 10(11) ions cm-2. No evidence for the formation of the Fe(Si) phase was found. This phenomenon was interpreted in terms of the relaxation of the high level of energy deposited in electronic excitations along the path of Pb ions in the target, which induces extensive stress and strain that could destabilize the amorphous structure.  相似文献   
6.
7.
Baryon rapidity loss in relativistic Au + Au collisions   总被引:4,自引:0,他引:4  
An excitation function of proton rapidity distributions for different centralities is reported from AGS Experiment E917 for Au+Au collisions at 6, 8, and 10.8 GeV/nucleon. The rapidity distributions from peripheral collisions have a valley at midrapidity which smoothly change to distributions that display a broad peak at midrapidity for central collisions. The mean rapidity loss increases with increasing beam energy, whereas the fraction of protons consistent with isotropic emission from a stationary source at midrapidity decreases with increasing beam energy. The data suggest that the stopping is substantially less than complete at these energies.  相似文献   
8.
For the semiinfinite Ising model with quenched boundary disorder, we prove concavity inequalities for the difference of wall tensions associated with the minus and plus phases. These inequalities generalize phenomenological equalitiesknown as Cassie's law.  相似文献   
9.
The current status of the understanding of jet quenching in nuclear collisions at RHIC is reviewed. The experimentally large level of suppression of jets in Au+Au collisions at RHIC is a success, but also introduces a challenge in terms of quantitative understanding of the properties of the collision zone. The medium appears to be equally black to all interacting probes utilized to date, limiting the amount of tomographic information that can be obtained from quenching phenomena. In order to recover this information, a probe to which the medium is gray needs to be found. PACS 25.75.-q  相似文献   
10.
The alkylation reaction of 2-mercapto-1-methylimidazole 1b with 2-chloroacetonitrile and 2-chloropropionitrile produced S-alkyl methimazole chlorides 2a and 2b which were subjected to anion metathesis with lithium bis(trifluoromethanesulfonyl)amide, LiNTf(2), to afford nitrile functionalized methimazole-based room temperature ionic liquids 3a and 3b in 94% and 89% yields, respectively. Ionic liquids 3a and 3b have reasonably wide electrochemical windows. The efficient extraction of Ag(+) from aqueous media into 3a and 3b is also reported.  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