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31.
32.
Guosong Wu Xiaoqin Zeng Wenbin Ding Xingwu Guo Shoushan Yao 《Applied Surface Science》2006,252(20):7422-7429
Ceramic thin films have been widely used to protect the metal substrate as coatings in the past years. In order to improve the poor corrosion resistance of AZ31 magnesium alloy, the study in this paper used the electron beam evaporation method to prepare ceramic PVD films on its surface with TiO2 and Al2O3 as donors, respectively. Atomic force microscopy (AFM), scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS), Auger electron spectroscopy (AES) and X-ray diffraction (XRD) were used to investigate the surface morphology, composition and microstructure of the thin films. Both films deposited on AZ31 took on compact top surface morphologies and grew as amorphous structures on substrate. AES test not only showed that films compositions deviated the standard stoichiometric ratios, but also found that element Mg diffused into films and existed as magnesium oxide in the TiOx film as well as the AlOx film. In the electrochemical corrosion test, the AlOx coating on AZ31 exhibited the largest electrochemical impedance in a 3.5% NaCl solution. But it did not show better corrosion resistance than others for the poorer adhesion. Even if its thickness was small, the TiOx coating on AZ31 exhibited the best corrosion resistance in this study. According to the observation and analysis, the damage of these films on AZ31 in aggressive solutions was mainly due to the existence of pores, microcracks, vacancies and poor adhesion between coating and substrate. 相似文献
33.
Chen-liang Li Jin-ping Zeng 《应用数学学报(英文版)》2007,23(1):79-90
We consider several synchronous and asynchronous multisplitting iteration schemes for solving aclass of nonlinear complementarity problems with the system matrix being an H-matrix.We establish theconvergence theorems for the schemes.The numerical experiments show that the schemes are efficient forsolving the class of nonlinear complementarity problems. 相似文献
34.
The fission barrier for ^240pu is investigated beyond the second saddle point in the potentiM energy surface by the constrained relativistic mean field method with the newly proposed parameter set PK1. The microscopic correction for the centre-of-mass motion is essentiM to provide the correct potential energy surface. The shell effects that stabilize the nuclei against the fission is also investigated by the Strutinsky method. The shapes for the ground state, fission isomer and saddle-points, etc, are studied in detail. 相似文献
35.
In this note we study constant mean curvature surfaces in asymptotically flat 3-manifolds. We prove that, outside a given compact subset in an asymptotically flat 3-manifold with positive mass, stable spheres of given constant mean curvature are unique. Therefore we are able to conclude that the foliation of stable spheres of constant mean curvature in an asymptotically flat 3-manifold with positive mass outside a given compact subset is unique.
36.
37.
Wei Gang SU Huai Jie ZHONG 《数学学报(英文版)》2006,22(2):515-522
This paper introduces the concept of the generalized Riesz operators and the concept of the generalized West decomposition of a general operator which generalizes the definition of the West decomposition of Riesz operators, and proves that the following three statements are equivalent on a general Banach space:
(a) Every generalized Riesz operator has the generalized West decomposition;
(b) Every operator makes strong Stampfli theorem true; Every operator has Apostol's compact correction. 相似文献
38.
文章针对焊件检测过程中需大量采集和分析实时图像的要求 ,利用小波分析的特点 ,相关跟踪识别视频图像运动状态 ,实现自动采集、分析处理和储存一并完成 ,解决了视频图像连续捕获不能得到高像质的问题。 相似文献
39.
In this paper, we give an application ofUV-decomposition method of convex programming to multiobjective programming, and offer a new algorithm for solving semi-infinite multiobjective programming. Finally, the superlinear convergence of the algorithm is proved. 相似文献
40.
本文主要论证了在不完全市场条件下带风险指数的金融均衡的存在性,并揭示其均衡结构的特征.本文中建立的模型是一、二期货币投入产出金融经济且具有可微的资产结构,这一模型包括了许多具有特殊资产结构的均衡模型,如实资产结构、虚资产结构、恒秩资产结构的均衡模型.因此本文的这一模型具有广泛的应用前景和实用价值.接着给出了本文的金融均衡的存在性定理,再借助微分拓扑给出它的证明过程,这一证明过程较之以前证明均衡存在性的经典方法(如Duffie,D&W.Shfer(1985)的方法)要简便得多.同时也应注意到本文的这一结论既适用于资产市场下会随机风险因素的情形,也适用于商品空间为无限维的情形,除此之外,还给出了怎样判别资产结构是否属于T类的判别法,为检验均衡存在性提供了更为便利的途径.最后,本文论证了在金融市场里,尽管由于稀缺性的存在,从而导致均衡分配的多样化,然而均衡分配集却形成了一光滑子流,但该流形的维数与稀缺性有关.换句话说,尽管市场是不完全的,但均市分配不确定性的反却是可比的.如此使得人们对均衡资产结构的认识更进一步. 相似文献