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1.
Supported metal catalysts, particularly noble metals supported on SiO2, have attracted considerable attention due to the importance of the silica–metal interface in heterogeneous catalysis and in electronic device fabrication. Several important issues, e.g., the stability of the metal–oxide interface at working temperatures and pressures, are not well-understood. In this review, the present status of our understanding of the metal–silica interface is reviewed. Recent results of model studies in our laboratories on Pd/SiO2/Mo(1 1 2) using LEED, AES and STM are reported. In this work, epitaxial, ultrathin, well-ordered SiO2 films were grown on a Mo(1 1 2) substrate to circumvent complications that frequently arise from the silica–silicon interface present in silica thin films grown on silicon.  相似文献   
2.
White blood cell detection is one of the most basic and key steps in the automatic recognition system of white blood cells in microscopic blood images. Its accuracy and stability greatly affect the operating speed and recognition accuracy of the whole system. But there are only a few methods available for cell detection or segmentation due to the complexity of the microscopic images. This paper focuses on this issue. Based on the detailed analysis of the existing two methods--threshold segmentation followed by mathematical morphology (TSMM), and the fuzzy logic method--a new detection algorithm (NDA) based on fuzzy cellular neural networks is proposed. NDA combines the advantages of TSMM and the fuzzy logic method, and overcomes their drawbacks. With NDA, we can detect almost all white blood cells, and the contour of each detected cell is nearly complete. Its adaptability is strong and the running speed is expected to be comparatively high due to the easy hardware implementation of FCN. Experimental results show good performance.  相似文献   
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4.
Removal of gold from basic solutions containing [Au(CN)2]? has been demonstrated using the inherently conducting polymer polypyrrole. Polymers containing sulfonated aromatic dopants have been found to display a significant ability to remove gold from such solutions. Experiments performed in solutions containing both gold and copper cyanide complexes indicate that the recovery process is not highly selective. However, the polypyrroles used display significantly faster rates of gold recovery than activated carbon. © 2003 Society of Chemical Industry  相似文献   
5.
原油基压裂液研究   总被引:5,自引:1,他引:4  
研制了一种适用于低压、低渗、水敏性储集层的新型原油基压裂液体系。根据基液原油的组分合成相应的增稠剂,增稠剂在原油中与交联剂反应,形成网状结构,使原油成为黏度可以调控的冻胶,从根本上改变了油基压裂液以柴油、煤油为基液的现状,降低了油基压裂液的成本,同时还提高了压裂液的抗温、抗剪切和破胶性能,并将交联时间缩短到2h以内,可以满足现场压裂施工的要求,大大降低了施工强度和压裂改造的综合成本。在青海油田进行的现场先导试验取得成功。图9表1参5  相似文献   
6.
对三网互联的几个关键技术进行分析与研究,介绍利用IP技术解决有线电视网地址选择问题,探讨怎样将ATM技术与IP技术相互融合,使真正的信息高速公路成为现实,阐述利用H.323标准全面解决视频网络方案。  相似文献   
7.
This letter analyzes the saturated throughput for multicast switches with multiple input queues per input port. Under the assumptions of a Poisson uniform traffic model and random packet scheduling policy, we derive the multicast switch saturated throughput under different fanouts. To verify the analysis, extensive simulations are conducted with different switch sizes and fanouts. It is shown that the theoretical analysis and the simulation results have a discrepancy less than 1.9%. Results from this letter can be used as a guidance to design the optimal queuing for multicast switches.  相似文献   
8.
A series of studies of top European and other firms has revealed patterns of design management associated with commercial success. Firms that invest resources and professional expertise in product and industrial design in traditional and new industries have been commercially more successful than firms that pay less attention to these aspects of design. As an industry matures there is a shift in emphasis from design associated with technological innovation, to designs supporting technical improvements, and then to supporting user needs, fashion and product variants. These issues are illustrated through the history of the evolution of the bicycle.  相似文献   
9.
Reviews the book, Constructing the subject: Historical origins of psychological research by Kurt Danziger (1990). Kurt Danziger's Constructing the Subject: Historical Origins of Psychological Research is a book of singular importance because it provides such a penetrating analysis, and does so in a manner that is cause for considerable reflection. In brief, Danziger provides a history lesson that not only situates the names and the projects of experimental psychology in the first part of this century, but also aims to clarify the project of knowledge generation both past and present. Indeed, shades of Quine, Kuhn, and Hesse permeate this book in a way that demands psychologists examine their own investigative practices and logics of justification. Through Wundt, through Galton, through Ebbinghaus and others, Danziger illuminates the development of experimental psychology along with the historical and philosophical vicissitudes that have given rise to numerous psychological knowledge claims. If it is true that we must understand our history in order to understand our present, then Danziger's book should be required reading in all research laboratories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
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