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   12篇
  免费   0篇
化学   6篇
力学   5篇
数学   1篇
  2013年   1篇
  2003年   2篇
  2001年   1篇
  1998年   1篇
  1990年   1篇
  1986年   1篇
  1974年   1篇
  1972年   1篇
  1969年   1篇
  1968年   2篇
排序方式: 共有12条查询结果,搜索用时 15 毫秒
1.
We consider the problem of steady incompressible viscous fluid flow about a rotating sphere, with the flow specified on a sphere of finite radius, which reduces to the solution of the complete Navier-Stokes equations.The dimensionless stream functions and circulai velocity are sought in the form of series in powers of the Reynolds numbers, which converge for small values of this number. Recurrence formulas are derived for determining the coefficients of these series. The pressure, rotational resistance torque, and drag are determined. It is established that the rotating sphere has higher drag than a stationary sphere. The leading term of the series in powers of the Reynolds number for the drag and resistive torque is calculated.  相似文献   
2.
3.
Cyclopalladated -(p-tolylimino)benzylruthenocene reacts with metallic tin in a way similar to ferrocene analogs, yielding bis-chelate diruthenocenyl tin(IV) compound as a result of transmetalation.  相似文献   
4.
The reactions of chiral benzyl- and ethyl(phenyl)ferrocenylphosphines with (acetonitrile)(4-cyclopentadienone)(5-cyclopentadienyl)ruthenium trifluoromethylsulfonate proceed diastereoselectively through the attack on the cyclopentadienone ring to form planar chiral 2-phosphonioruthenocenols as mixtures of two diastereomers in ratios of 1.7 : 1 and 2 : 1, respectively.  相似文献   
5.
An analysis is presented of the steady-state asymmetric motion of an incompressible viscous liquid between two concentric spheres rotating with constant angular velocities about various axes passing through their common center. The reaction force of the liquid on the inner sphere is determined; this force reduces to a resistive torque.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 3, pp. 179–180, May–June, 1974.  相似文献   
6.
p-Tolyliminoalkylruthenocenes—Schiff's bases of the ruthenocene series—react with sodium tetrachloropalladate in the presence of carboxylate anion similarly to their ferrocenyl analogs to give cyclopalladation products. The optical rotation values of the products resulting from carbonylation of palladated ferrocene and ruthenocene aldimines, prepared under conditions of asymmetric catalysis, followed by liberation of the aldehyde group were used to determine the stereochemistry and enantiomeric purity of the cyclopalladation products. Centre Nationale de Recherches Scientifiques, URA 419 4, pl. Jussieu, Bat. F, 75252 Paris, France. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1421–1424, July, 1998.  相似文献   
7.
We consider the stead y flow of a viscous fluid around a sphere of finiteradius in non-linear formulation. The equations of motion are written in non-dimensional terms. We seek their solution as the expansion of the unknown stream function in a series of powers of the Reynolds number, the coefficients of which are polynomials in associated Legendre functions of the first kind. Recurrence relations are given for the sequential determination of all coefficients. The velocity and pressure fields are determined. The drag is calculated. Numerical calculations are carried out.  相似文献   
8.
9.
The formation of a new chiral center in the reactions of ketone 4-MeOC6H4CH(Et)C(O)Et with planar-chiral 2-lithio-1-methyl- and 1-chloro-2-lithioferrocenes proceeded stereoselectively to give two diastereomers in a ratio of 3 : 2 or a single diastereomer, respectively, out of four possible diastereomeric 4-aryl-3-ferrocenylhexan-3-ols. The replacement of the hydroxy group in the resulting compounds by hydrogen under the conditions of ionic hydrogenation was studied. The configurations of the reaction products were established by X-ray diffraction analysis and 1H NMR spectroscopy.  相似文献   
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