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   13篇
  免费   0篇
化学   11篇
力学   2篇
  2007年   1篇
  2005年   1篇
  2004年   3篇
  2003年   2篇
  2001年   2篇
  2000年   1篇
  1983年   1篇
  1974年   1篇
  1971年   1篇
排序方式: 共有13条查询结果,搜索用时 31 毫秒
1.
2-Carboxyphenylamides of aroylacetic acids undergo cyclization when treated with dehydrating agents to give 2-[(Z)-2-aryl-2-hydroxy-1-ethenyl]-4H-3,1-benzoxazin-4-ones. Crystal and molecular structure of the latter phenyl derivative was studied by X-ray crystallography. Original Russian Text ? E.S. Vostrov, A.A. Novikov, A.N. Maslivets, Z.G. Aliev, 2007, published in Zhurnal Organicheskoi Khimii, 2007, Vol. 43, No. 2, pp. 232–235.  相似文献   
2.
3.
4.
5.
Thermal decarbonylation of 5-aryl-4-phenyl-2,3-dihydrofuran-2,3-diones gives rise to intermediate aroyl(phenyl)ketenes which react with nonactivated Schiff bases, N,N'-dicyclohexylcarbodiimide, and p-di-methylaminobenzonitrile according to the [4 + 2]-cycloaddition pattern with formation of 6-aryl-5-phenyl-4H-1,3-oxazin-4-ones. Reactions of 5-aryl-4-phenyl-2,3-dihydrofuran-2,3-diones with activated Schiff bases at a temperature below the thermolysis temperature lead to 4-aroyl-4-phenyltetrahydropyrrole-2,3-diones.  相似文献   
6.
The possibility of the use of the method of correlation pleiads for the isolation of the absorption regions in the IR spectra of substituted 1,3-dioxanes in which the characteristic absorption bands for the individual stereoisomers of the substances appear was studied. It is shown that the configurations of the investigated compounds can be determined on the basis of the characteristic absorption bands by instructing a computer to distinguish forms.  相似文献   
7.
8.
We consider the axisymmetric problem of determination of the stress-strain state in an elastic half-space in the case of a circular line of separation of the boundary conditions on the boundary plane z = 0. We assume that on the entire boundary z = 0 the tangential stress rz = 0, while inside the circle r a (z = 0) the normal displacement uz is known and in its exterior the normal stress z is given. In addition, we assume that body forces are acting in the half-space. The investigation of problems of similar kind presents interest in connection with the application of A. A. Il'yushin's method of elastic solutions to the problem of the indentation of punches into a nonlinear-elastic, in particular, into an elastoplastic half-space.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 110–115, July–August, 1971.The author wishes to thank M. Ya. Leonov for his valuable suggestions during the preparation of this paper.  相似文献   
9.
10.
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