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11.
Hybridization of Banana fibers with glass fibers has been found to reduce the water absorption behavior of the composites in an earlier work by us. Banana fibers were hybridized with glass and different layering patterns were followed in the preparation of the composites. The effect of the various layering patterns on the water absorption of the composites was studied. It was found that water diffusion occurs in the composite depending on the layering pattern as well as the temperature. In all the experiments, it has been found that composites with an intimate mixture of glass and banana show the maximum water uptake except for temperature of 90°C. At 90°C the maximum water uptake is found to be for composites where there is one layer of banana and another layer of glass. The water uptake follows the same trend as that in all other temperatures till a time span of 4900 min is reached. The kinetics of diffusion was found to be Fickian in nature. The various thermodynamic parameters like sorption coefficient, diffusion coefficient. Enthalpy change, entropy change, and activation energy of the various composites were calculated. From all the calculations it has been concluded that layering pattern is an important parameter which controls the water absorption of the composites. The layering pattern Cg‐b‐g was found to have the lowest water uptake. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
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The coating and granulation of solid particles in a fluidized bed is a process which converts pumpable and atomizable liquids (solutions, slurries, melts) into granular solids in one step through drying. Although this process has been applied in industry for several years, there is still a lack of understanding the physical fundamentals and the mechanisms by which spherical granules are formed. Hence a new method was developed which allows the direct observation of the subsequent particle-forming mechanisms such as droplet deposition, spreading, wetting and drying. The authors will present a laboratory scale apparatus in which a single freely suspended particle can be coated under well defined and constant coating and drying conditions. With this device, particle-growth-rate and the development of particle morphology were measured and investigated under various experimental conditions. 相似文献
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惠南庄泵站计算机监控系统结构及特点 总被引:1,自引:1,他引:0
惠南庄泵站是南水北调中线工程唯一的泵站,担负着向北京市供水的重要任务.文中从泵站的工程背景及运行方式出发,提出了泵站计算机监控系统的设计原则,详细阐述了系统的开放式分层分布结构、主要设备的配置及功能,并对系统的主要特点进行了分析与总结,可供大中型泵站计算机监控系统的设计及施工借鉴. 相似文献
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The properties of alkane lubricants confined between two approaching solids are investigated by a model that accounts for the curvature and the elastic properties of the solid surfaces. We consider linear alkane molecules of different chain lengths, C3H8, C4H10, C8H18, C9H20, C10H22, C12H26, and C14H30 confined between smooth gold surfaces. We observe well-defined molecular layers develop in the lubricant film when the width of the film is of the order of a few atomic diameters. An external squeezing-pressure induces discontinuous changes in the number n of lubricant layers. We find that with increasing alkane chain length, the transition from n to n - 1 layers occurs at higher pressure, as expected based on the increasing wettability with increasing chain length. We obtain good correlation between our theoretical results and wear experiments. 相似文献
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露头碳酸盐岩旋回层序的识别与划分 总被引:5,自引:0,他引:5
在海相碳酸盐岩新区勘探中,露头层序地层学是一种重要的勘探手段。归纳了露头碳酸盐岩米级旋回层序的识别特征和划分依据,识别和测量了北京西山丁家滩剖面的米级旋回层序,并分析其垂直叠加型式,划分了长周期旋回层序。结果表明,通常是4~6个向上变厚并变浅的米级旋回层序构成一个五级旋回层序;4个总体向上变厚并变浅的五级旋回层序构成一个四级旋回层序;3~5个四级旋回层序构成一个更大级别的总体向上变厚变浅的序列。图1表1参6(邹冬平摘) 相似文献
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分析了朱庄矿、岱河矿、芦岭矿 3个单位使用链条锅炉的运行缺陷 ,采用分层燃烧技术进行锅炉改造 ,取得显著的经济效益 相似文献
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This paper deals with the problem of finding graph layerings restricted to a given maximal width. However, other than previous approaches for width-restricted layering, we take into account the space for dummy nodes, which are introduced by edges crossing a layer. The main result is that the problem of finding a width-restricted layering under consideration of dummy nodes is NP-complete even when all regular nodes have the same constant width and all dummy nodes have the same constant width. 相似文献