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   48篇
  免费   0篇
  国内免费   1篇
化学   17篇
力学   20篇
数学   2篇
物理学   10篇
  2022年   1篇
  2021年   1篇
  2018年   1篇
  2017年   1篇
  2016年   3篇
  2015年   1篇
  2014年   2篇
  2013年   2篇
  2012年   4篇
  2011年   2篇
  2010年   3篇
  2009年   1篇
  2008年   3篇
  2007年   2篇
  2006年   1篇
  2004年   1篇
  2003年   3篇
  2002年   4篇
  1999年   1篇
  1996年   1篇
  1991年   1篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1985年   2篇
  1984年   1篇
  1983年   1篇
  1981年   1篇
  1978年   1篇
  1973年   1篇
排序方式: 共有49条查询结果,搜索用时 15 毫秒
1.
A magnetic field and temperature was shown to affect disperse composition, electrophoretic behavior, and aggregation stability of synthesized magnetite particles. When synthesis proceeds, a process of the nucleation of ultramicroscopic Fe3O4 particles prevails over a process of their aggregation. Here an electrostatic factor of stability of magnetite suspension plays an important role. An application of the magnetic field decreases the aggregation stability and increases the sedimentation rate of product particles.  相似文献   
2.
Catalytic thermal destruction of ethylenediaminetetraacetic acid and its complexes with nickel, iron, and cobalt in nitrate solutions on carbon materials (activated unwoven material, sibunite, and BAU–A activated carbon) was studied. The activation energies of thermal destruction were calculated.  相似文献   
3.
A method is described for the experimental study of the characteristics of the bubble phase in a developed fluidized bed in examples of disperse materials belonging to groups A and B in the well-known classification of Geldart [1], which distinguished four groups of fluidizable materials according to the densities and dimensions of the solid particles. The method developed makes it possible to determine the average and local characteristics of the phase of the bubbles in apparatus of arbitrary dimensions. Depending on whether the material belongs to group A or group B of the classification, the distributions are found of the bubbles in respect of their vertical dimensions and their velocities, as are also the relative numbers of occasions when agglomerates coalesce and form, and the relative times of contact between the inhomogeneities and a sensor in a flat fluidized bed.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 71–76, September–October, 1987.  相似文献   
4.
Stability analysis of noncircular shells is performed with allowance for nonlinear subcritical deformation. Explicit expressions for the rigid displacements of elements of noncircular cylindrical shells are obtained and used to construct shape functions of an effective quadrilateral finite element of natural curvature. A finiteelement algorithm for solving problems of nonlinear deformation and stability of shells is developed. Stability problem of an elliptic cylindrical shell is considered. The effect of the ellipticity and subcritical nonlinear deformation of the shell on the critical load is studied. Results obtained are compared with available experimental data.  相似文献   
5.
A finite-element formulation of the solution of problems of the stability of non-circular cylindrical shells taking into account their bending moments and the non-linearity of their precritical stress-strain state in proposed. Explicit expressions for the displacements of the elements of non-circular cylindrical shells as rigid bodies are derived by integration of the equations obtained by equating the components of the linear strains to zero. These expressions are used to construct shape functions of an effective quadrilateral finite element of the natural curvature. An effective algorithm is developed for investigating the non-linear deformation and stability of the shells. The stability of a cylindrical shell of elliptical cross-section under transverse bending is investigated. The influence of the ellipticity and non-linearity of the deformation on the shell's stability is determined. The results of the analysis are compared with experimental data.  相似文献   
6.
7.
Sorption characteristics of synthetic calcium aluminosilicates (CAS) obtained in the multicomponent CaCl2–AlCl3–KOH–SiO2–H2O system are presented. The isotherms of Sr2+ sorption on CAS from aqueous solutions containing no additional salts were measured for Sr2+ concentration from 0.5 to 11.1 mmol/L and solid to liquid phase ratio S: L = 1: 100. The maximum sorption capacity of synthetic CAS was determined, the phase distribution constants of Sr2+ ions at different S: L ratios were found. The recoveries of Sr2+ ions from solutions containing 0.01 mol/L Ca(NO3)2 and from a solution simulating water of the Mayak plant sewage pond No. 11 were determined.  相似文献   
8.
Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 4, pp. 143–148, July–August, 1989.  相似文献   
9.
Previously unknown 2,3,6,7,10,11-hexakis(dodecyloxy)triphenylene and -(tetradecyloxy)triphenylene were synthesized. The structures of the synthesized compounds were proved by elemental analysis and spectral methods. Polymesomorphism was found for the first time and studied for substances of the hexaalkoxytriphenylene homologic series, as well as liotropic mesomorphism in a series of organic solvents.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1676–1681, August, 2004.  相似文献   
10.
A facility using a californium neutron source and a method for the neutron activation analysis of gold were developed. The sensitivity of the determination is 0.1 g/t. The sources of random and systematic errors have been studied. It has been concluded that in prospection and evaluation of gold ore deposits, the traditional test tube analysis for gold may be replaced with the developed method.  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