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   49篇
  免费   3篇
  国内免费   10篇
化学   17篇
力学   15篇
数学   9篇
物理学   21篇
  2013年   2篇
  2012年   1篇
  2011年   18篇
  2010年   11篇
  2009年   4篇
  2008年   1篇
  2006年   1篇
  2005年   4篇
  2004年   4篇
  2003年   1篇
  2002年   1篇
  2001年   4篇
  2000年   1篇
  1995年   2篇
  1994年   1篇
  1993年   1篇
  1992年   2篇
  1991年   1篇
  1989年   1篇
  1984年   1篇
排序方式: 共有62条查询结果,搜索用时 15 毫秒
41.
The dynamics of the reshocked multi-mode Richtmyer-Meshkov instability is investigated using 513×257 2three-dimensional ninth-order weighted essentially nonoscillatory shock-capturing simulations.A two-mode initial perturbation with superposed random noise is used to model the Mach 1.5 air/SF6 Vetter-Sturtevant shock tube experiment. The mass fraction and enstrophy isosurfaces,and density cross-sections are utilized to show the detailed flow structure before,during,and after reshock.It is shown that the mixing layer growth agrees well with the experimentally measured growth rate before and after reshock.The post-reshock growth rate is also in good agreement with the prediction of the Mikaelian model.A parametric study of the sensitivity of the layer growth to the choice of amplitudes of the short and long wavelength initial interfacial perturbation is also presented.Finally,the amplification effects of reshock are quantified using the evolution of the turbulent kinetic energy and turbulent enstrophy spectra,as well as the evolution of the baroclinic enstrophy production,buoyancy production,and shear production terms in the enstrophy and turbulent kinetic transport equations.  相似文献   
42.
This paper is concerned with three-dimensional numerical simulation of a plunging liquid jet. The transient processes of forming an air cavity around the jet, capturing an initially large air bubble, and the break-up of this large toroidal-shaped bubble into smaller bubbles were analyzed. A stabilized finite element method (FEM) was employed under parallel numerical simulations based on adaptive, unstructured grid and coupled with a level-set method to track the interface between air and liquid. These simulations show that the inertia of the liquid jet initially depresses the pool's surface, forming an annular air cavity which surrounds the liquid jet. A toroidal liquid eddy which is subse- quently formed in the liquid pool results in air cavity collapse, and in turn entrains air into the liquid pool from the unstable annular air gap region around the liquid jet.  相似文献   
43.
Recent developments in scanning holographic microscopy that offer the prospects of new quantitative tools and imaging modalities in bio, micro, and nano sciences are reviewed. The versatility of the method is emphasized. Scanning holography can operate in an incoherent mode for fluorescence imaging, in a coherent mode for quantitative phase imaging, or in a tomographic mode for axial sectioning and rejection of the out-of-focus haze. Possible applications are illustrated with examples, and future prospects ...  相似文献   
44.
本实验用~1H-NMR法研究了中国生漆饱和漆酚冠醚化合物的结构与碱金属离子选择电极性能间的关系。研究结果表明,只有当饱和漆酚冠醚化合物实现全关环时才与碱金属离子有高的络合容量,且反式构型化合物的络合容量比顺式构型化合物大得多。  相似文献   
45.
In order to search for new potent anti-cancer agents, a series of boswellic acid derivatives were designed and synthesized. Six of them were identified by IR, NMR and MS as new compounds and biologic assay of anti-cancer is underway.  相似文献   
46.
Recently, silver as an electrochemical deposit on copper substrata has been attracting much attention in the microelectronics field. To deposit nano-scale silver particles on copper, immersion plating using cyanide-based baths is commonly used. In this study, non-toxic ethanol was used as the plating solution. Sputtered copper samples were immersed in an ethanol-based solution containing 0.2 g·L^-1 silver for silver deposition. The silver deposits were characterized by a field emission scanning electron microscope (FE-SEM), an energy dispersive X-ray spectroscope (EDS), and an atomic force microscope (AFM). It was found that the deposited particles are metallic silver. After 3 s immersion, fine particles whose diameters were around 6 nm had covered about 40% of the surface of the copper substrata. After 10 s immersion, the copper surface was completely covered by silver particles, the diameters of which have increased to about 10-15 rim. After the whole surface was covered, a dense and smooth silver coating was obtained.  相似文献   
47.
林家翘 《力学进展》2003,33(2):161-165
近来,人们喜欢从历史的角度来探讨数学在生物学中的应用问题.这种趋势似乎可以看作是应用数学范围逐渐拓展的一种自然现象.但它所用到的数学概念和方法与以往应用数学所用的概念和方法并无本质区别.例如,我们在本文中简单描述了如何将耗散系统中的动理学原理用于研究蛋白质分子的结构和功能.在这些研究中,传统统计物理学的概念和方法可以用来成功地建立与经验数据相对应的假设及理论.   相似文献   
48.
1 IntroductionIn the theory of nonlinear optics[1], one is led to consider a nonlinear reduced wave equationwhere k is the wave number and n = n'(IuI') is a function of intensity Of the field and is calledthe index of refraction.We consider the case when the optical beam propagates in a quadratic index nledia sothat n'(luI') can be written aswhere no and n1 are constants.With IuI = O(k--'), d > 0, and following the discussion of this equation in two dimensionalspace (see [2]), we writeSubst…  相似文献   
49.
MULTISCALE ISSUES IN DNS OF MULTIPHASE FLOWS   总被引:1,自引:0,他引:1  
  相似文献   
50.
Cells tend to form hierarchy structures in native tissues.Formation of cell aggregates in vitro such as cancer spheroids and embryonic bodies provides a unique means to study the mechanical properties and biological behaviors/functions of their counterparts in vivo.In this paper,we review state-of-the-art experimental approaches to assess the mechanical properties and mechanically-induced responses of cell aggregates in vitro.These approaches are classified into five categories according to loading modality,including micropipette aspiration,centrifugation,compression loading,substrate distention,and fluid shear loading.We discussed the advantages and disadvantages of each approach,and the potential biomedical applications.Understanding of the mechanical behavior of cell aggregates provides insights to physical interactions between cells and integrity of biological functions,which may enable mechanical intervention for diseases such as atheromatosis and cancer.  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