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41.
The dye-sensitized TiO2 complex films were prepared by the dye coat onto TiO2 surfaces,and the sensitizing mechanism and adsorption properties of the dye-sensitized TiO2 complex films were inverstigated.The influence of the application conditions of dye adsorbed on TiO2 films on the amount of dye adsorption was discussed.Experimental results show that the concentration,the temperature of dye solutions and the dipping time of TiO2 films in the dye solutions have a significant influence on the amount of dye adsorption.Cell test indicates that the conversion efficiency of light to electricity increases with the amount of dye adsorption.  相似文献   
42.
河口水流、波浪、潮流、泥沙、河床变形二维数学模型   总被引:19,自引:0,他引:19  
根据河口“波浪掀沙,潮流输沙”的泥沙运动机制,引入“波浪幅射应力”反应波浪对水体和泥沙的驱动力.考虑波浪对底部泥沙作用力、波浪对水流挟沙能力的影响及风场对水流和泥沙运动的影响.同时考虑泥沙粒径大小、水体含盐度、含沙量及水流紊动程度等因素对絮凝沉速的影响.用ADI算法求解沿水深平均方程,破开算子法解悬移质不平衡输沙方程及河床变形方程,引入通度概念处理岸滩不规则边界,建立河口水流、波浪、潮流、泥沙、河床变形二维数学模型.通过实测资料及卫星摇感图像对所建数学模型进行检验,表明它可以较好地预测河口泥沙的运动  相似文献   
43.
Reviews the book, The saturated self: Dilemmas of identity in contemporary life by Kenneth J. Gergen (see record 1991-97621-000). There is, perhaps, no other concept as seminal for psychology as the self. For this reason alone, Kenneth Gergen's book represents an important contribution to our understanding of this influential concept. However, Gergen's vision is so broad, his arguments so compelling, and the implications so revolutionary, that the work defies confinement exclusively within the walls of academia. In essence, Gergen is articulating his vision of a postmodern world, and he lays an invitation squarely before the reader to come and partake. The conception of the self as private and autonomous is the focus of Gergen's postmodern challenge. In his chapter, "Social Saturation and the Populated Self," Gergen postulates that technological innovation in contemporary society has made possible a rapid proliferation of relationships. This he refers to as the "process of social saturation." Gergen's book constitutes a substantive contribution to psychology's on going understanding of the self. Copious examples are provided throughout, drawing on and extending scholarly debates. Also included are anecdotes and evidences from such far ranging domains as art, film, music, literature, and architecture. These not only clarify and reinforce his arguments, but also illustrate the scope and practicality of the position he espouses. Although readers may not embrace the gestalt of Gergen's vision of a postmodern culture, they are certain to find this book to be a provocative and rewarding read. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
44.
Steady-state and three-dimensional simulations were carried out to study the influences of geometrical parameters on the performance of PEMFC under different hydrating conditions. Flow fields, species transport, transport of water in polymer membrane and movement of liquid water in cathode and anode porous layers were determined, in order to accomplish a complete estimation of ohmic and concentration losses of PEMFC power. The geometrical parameters were thickness of the polymer membrane, cathode catalyst layer as well as gas channel to rib width ratio. Every simulation was made under different relative humidities of inlet flows (50 and 100%) for every change of characteristic length. Results show that the influence of the geometrical parameters on ohmic and concentration losses is of considerable importance. The performance of PEMFC is seriously affected under dehydrating conditions. However, such performance may be considerably improved by using suitable geometrical parameters. Cathode and anode liquid saturation may not only affect the transport of species, but also the polymer electrolyte water content. These results show the importance of simultaneously calculating both the water absorption and desorption through the polymer electrolyte and the liquid saturation in the cathode and anode porous mediums to obtain an actual view of ohmic and concentration losses of the PEMFC performance.  相似文献   
45.
美国西雅图先锋广场历史保护区的形成   总被引:1,自引:0,他引:1  
黄治 《规划师》2004,20(4):91-93
考察美国西雅图先锋广场历史保护区形成的过程,可以看出城市历史文化遗存的保护是经济与历史文化合力作用的结果,公众参与在城市历史文化保护工作中发挥着重要的作用。我国城市经济高速发展,保护与发展的矛盾冲突还没得到很好解决,先锋广场的例子对我们具有一定的参考价值。  相似文献   
46.
以镁法海绵钛生产工艺中大型无隔板镁电解槽的实际节能情况为例,探讨了在镁电解生产中的非生产耗电、生产耗电、漏电等因素造成的能量浪费,阐述了生产中粗镁直流电耗、电流效率、工作电压3者之间的关系,指出了影响电解槽工作电压的有关因素及降低电解槽工作电压的途径。  相似文献   
47.
In order to study water-gas transport processes in the gas-diffusion-layer (GDL) of a proton exchange membrane (PEM) fuel cell system, a multiphase, multiple-relaxation-time lattice Boltzmann model is presented in this work. The model is based on the mean-field diffuse interface theory and can handle the multiphase flows with large density ratios and various viscosities. By using the standard bounce back boundary condition and an approximate average scheme for the non-slip and wetting boundary walls, respectively, detailed liquid-gas transportation in the GDL, in which exact boundary condition is difficult to be implemented, can be simulated. Unlike most of lattice Boltzmann methods based on the Bhatnagar–Gross–Krook collision operator, the present model shows a viscosity-independent velocity field, which is very important in simulating multiphase flows where various viscosities coexist. We validate our model by simulating a static droplet on a wetting wall and compare with theoretical predictions. Then, we simulate a water-gas flow in the GDL of a PEM fuel cell and investigate the saturation-dependent transport properties under different conditions. The results are shown to be qualitatively consistent with the previous numerical and theoretical works.  相似文献   
48.
铝电解槽磁流体稳定性有限元分析   总被引:2,自引:0,他引:2  
本文采用有限元法求解分层磁流体小扰动方程系统特征值,研究铝电解槽稳定性。研究结果表明,在没有电磁力时,铝液表面波动(内波)是稳定的。存在电磁力时,它会激发铝液表面波动的某些低频长波分量不稳定性,高频短波不受影响。被激发的不稳定波动频率和扰动增长率与电流密度,磁感应强度垂直分量,铝电解槽长宽比,电解质和铝液的密度差,厚度等因素密切相关。减少电流密度,磁感应强度,增加电极距离和铝液厚度可以提高铝电解槽的稳定性。这对铝电解槽优化设计和在线控制有重要意义。  相似文献   
49.
在设计国际化的影响下,中国现代视觉设计中充满了受西方影响的视觉语言,“国际化”视觉符号的泛滥与“本土化”视觉语言的失语视觉现象非常突出。作为当今社会人与人交流载体的海报设计,要走出一条“民族个性”的道路,就必须根植于民族文化土壤中,向传统学习,并进行具有创造性的转化,使传统文化符号在当代海报设计中既具有“民族个性”又有“时代性”,这样,我们海报设计才能真正走“国际化”。  相似文献   
50.
时代的进步、民族文化的流失亟待我们去解决。我们呼吁民族意识的回归,寻求传统服饰文化的发展。  相似文献   
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