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61.
关于RNP和SCS的若干等价条件   总被引:1,自引:0,他引:1  
使用切片方法,讨论了Banach空间中有界闭凸子集的RNP和SCS的若干等价条件.  相似文献   
62.
New model compounds for poly[N,N′-bis(phenoxyphenyl)pyromellitimide] have been synthesized in order to investigate the formation of imine bonds which are proposed to form during the curing process and lead to crosslinking in the bulk polymer. Raman studies show that terminal amines can react with imide carbonyls during curing to form C?N bonds. The Raman band due to C?N appears at 1656 cm?1 and the band due to C?O closest to the imine bond is observed at 1742 cm?1. These results are in agreement with previously published results on vapor deposited polyimide films.  相似文献   
63.
The motion of a moored floating body under the action of wave forces, which is influenced by fluid forces, shape of the floating body and mooring forces, should be analysed as a complex coupled motion system. Especially under severe storm conditions or resonant motion of the floating body it is necessary to consider finite amplitude motions of the waves, the floating body and the mooring lines as well as non-linear interactions of these finite amplitude motions. The problem of a floating body has been studied on the basis of linear wave theory by many researchers. However, the finite amplitude motion under a correlated motion system has rarely been taken into account. This paper presents a numerical method for calculating the finite amplitude motion when a floating body is moored by non-linear mooring lines such as chains and cables under severe storm conditions.  相似文献   
64.
V Kumar  B N Roy  D K Rai 《Pramana》1992,38(1):77-90
We have calculated total and differential cross-sections for 1sns (n = 2, 3, 4) electron impact excitation of hydrogen and hydrogenic ions at various energies in Coulomb-projected Born approximation. Distortion due to static interactions, target polarization and exchange effects has been incorporated in the initial channel. The present calculations have been compared with other theoretical and experimental results.  相似文献   
65.
讨论了 C\+n 中有界对称域的加权Bergman空间上符号属于 L\+2\-a(Ω, dV\-λ) 的小Hankel算子, 利用符号 Φ 的某种积分变换,给出了小Hankel算子 h\-Φ 属于Schatten理想 S\-p 的特征.  相似文献   
66.
In this paper, a projection method is presented for solving the flow problems in domains with moving boundaries. In order to track the movement of the domain boundaries, arbitrary‐Lagrangian–Eulerian (ALE) co‐ordinates are used. The unsteady incompressible Navier–Stokes equations on the ALE co‐ordinates are solved by using a projection method developed in this paper. This projection method is based on the Bell's Godunov‐projection method. However, substantial changes are made so that this algorithm is capable of solving the ALE form of incompressible Navier–Stokes equations. Multi‐block structured grids are used to discretize the flow domains. The grid velocity is not explicitly computed; instead the volume change is used to account for the effect of grid movement. A new method is also proposed to compute the freestream capturing metrics so that the geometric conservation law (GCL) can be satisfied exactly in this algorithm. This projection method is also parallelized so that the state of the art high performance computers can be used to match the computation cost associated with the moving grid calculations. Several test cases are solved to verify the performance of this moving‐grid projection method. Copyright © 2004 John Wiley Sons, Ltd.  相似文献   
67.
ICF研究中的Rayleigh-Taylor不稳定性实验用靶   总被引:2,自引:2,他引:0       下载免费PDF全文
 概述了当前研究Rayleigh-Taylor不稳定性增长实验所用的靶型情况。从实验用靶来看,调制靶的设计正从平面向立体发展,出现了球形和柱形等新靶形,制备手段包括精密机械微加工、激光束、电子束和离子束加工、半导体工艺和微米纳米技术加工等。根据对国外新靶型的研究,结合国内工艺条件和实验需求,对国内可能采用的靶型进行了研究探索。  相似文献   
68.
潜热型热功能流体强化换热分析   总被引:4,自引:0,他引:4  
本文建立了分析带有相变微胶囊的潜热型热功能流体的流动和换热过程数理模型,应用有限差分法和移动热源法进行联合求解。计算结果表明,相变微胶囊的加入:较好地提高了流体的换热性能。获得了相变颗粒大小和体积分数对强化换热影响等结果。计算结果对该类流体的设计和应用提供了理论依据。  相似文献   
69.
ICF靶丸中液氢层厚度的确定   总被引:1,自引:1,他引:0       下载免费PDF全文
 利用靶丸内部的质量守恒,提出了计算惯性约束聚变靶丸内液氢层厚度的函数关系式,从而得到了求解惯性约束聚变靶丸内液氢层厚度的一般模型,并在此基础上对影响液氢层厚度的各类因素如温度、充气密度等进行了讨论。该模型的分析方法同样适用于惯性约束聚变中的燃料气体氘、氚或者氘氚混合物。  相似文献   
70.
In this work, chemically and topographically nanopatterned surfaces were produced by a top-down processing approach for biosensing devices. The nanopatterning was the result of the combination of plasma polymerisation (pp) of biofunctional materials and colloidal lithography techniques. The morphological and chemical properties induced by the plasma deposition-etching treatment were characterised by optical method combining ellipsometry and Fourier Transform Infrared spectroscopy studies. This method supported by atomic force microscopy measurements, allowed the full optical characterization of each step of the top-down process. The optical characterization of the end-up nanopatterned samples demonstrated that the chosen process is able to produce well-defined nanostructured surfaces with controlled chemical and morphological properties.  相似文献   
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