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991.
电力系统微机型产品的电磁兼容设计   总被引:2,自引:1,他引:1  
张亚东 《广东电力》2002,15(3):45-48
从分析电力系统中电磁干扰的来源、传输途径入手,对应用于电力系统的微机型产品设计中的电磁兼容问题进行了较为系统的探讨,并提出了行有效的解决措施。  相似文献   
992.
膜-粉末炭反应器净化微污染源水   总被引:2,自引:2,他引:0  
采用膜-粉末炭反应器处理微污染源水的试验结果表明,该工艺对水中的有机物具有较好的净化效果,在水温《10℃的条件下,处理可生化性很低的三家店水库水时对CODMn的去除率仍保持在65%左右;工艺对CODMn、UV254、UV410的去除效果依次增强.  相似文献   
993.
大豆乳清的预处理   总被引:18,自引:0,他引:18  
针对“膜法回收大豆乳清中的生物活性物质”工艺中的预处理部分进行研究,发现絮凝离心处理分别可以去除乳清中65%左右的脂肪和90%左右的悬浮固体,袋式过滤和精密微孔管等精密过滤手段对乳清的预处理效果不佳,但是袋式过滤可以作为微滤之前的保安过滤方式,为了进一步去除乳清中的杂质和同时灭菌,微滤过程是必须的,包括絮凝离心和微滤在内的预处理过程可以在蛋白质损失率只有10%左右的情况下将悬浮固体全部去除,脂肪去除率高达90%以上。中试的试验结果验证了上述结论。  相似文献   
994.
Si3N4陶瓷材料由于具有很好的高温性能及高的力学性能,而被广泛地用于结构陶瓷,如切削刀具等。然而,因为其对缺陷很敏感,故易受灾难性的失效。人们发展了多种Si3N4增韧陶瓷,其中自增韧由于一些优异的性能越来越受到人们的重视。在此文中,着重介绍了影响Si3N4陶瓷长颗粒(柱状晶)晶粒生成的因素,并介绍了国内外对长颗粒Si3N4晶的控制研究。  相似文献   
995.
光通信用垂直腔面发射激光器的进展   总被引:1,自引:0,他引:1  
垂直腔面发射激光器(VCSEL)以其优异的性能有望成为信息时代的新光源.文章介绍了用于光通信的VCSEL的开发现状.  相似文献   
996.
G. Manassero  T. Tolio 《CIRP Annals》2004,53(1):389-392
One of the main problems faced while configuring or reconfiguring manufacturing systems is to rank alternative designs taking into account all the different aspects involved (both tangible and intangible). For this purpose the Analytic Hierarchy Process (AHP) is a well-known decision making support method that addresses this problem. A major drawback of AHP is that uncertainty in the judgments of the decision makers and the resulting impact on the ranking is not considered. In real situations, however, judgments based on perceived future scenarios are almost always uncertain. To solve this problem in this paper we present the first complete probabilistic extension to the AHP method. The new method provides the decision maker not only with information on the ranking of the alternatives but also the probability that the ranking remains stable even in presence of uncertainty in the judgements. We verified the validity of the new method in a real application developed for the Ferrari racing team.  相似文献   
997.
Compact Airborne Spectrographic Imager (CASI) hyperspectral data is used to investigate the effects of topography on the selection of spectral end members, and to assess whether the topographic correction improves the discrimination of rock units for lithologic mapping. A publicly available Digital Elevation Model (DEM), at a scale of 1:50,000, is used to model the radiance variation of the scene as a function of topography, assuming a Lambertian surface. Skylight is estimated and removed from the airborne data using a dark object correction. The CASI data is corrected on a pixel-by-pixel basis to normalize the scene to a uniform solar illumination and viewing geometry. The results show that topography has the effect of expanding end member clusters at times resulting in the overlap of clusters and that the correction process can effectively reduce the variation in detected radiance due to changes in local illumination. When topographic effects are embedded in the hyperspectral data, methods typically used for the selection of end members, such as the convex hull method, can miss end members or result in the selection of nonrepresentative pixels as end members. Thus, end members selected by some conventional methods are very likely “incomplete” or “nonrepresentative” if the topographic effect is embedded in the data. As shown in this study, the topographic correction can reveal hidden end members and achieve a better representation of end members via the statistical center of isolated clusters.  相似文献   
998.
P、V操作的概念以及使用在操作系统中非常重要、这里从一些新颖的角度来分析P、V操作,用P、V操作来实现进程的同步与互斥以及一种简单易行的逻辑关系则可以解决P操作嵌套时的执行次序。  相似文献   
999.
Polyethylene‐g‐polyacrylamide membranes were prepared by graft polymerization of acrylamide onto polyethylene films using a preirradiation method. The ion‐exchange membranes were obtained by the hydrolysis of grafted films so as to transform amide groups into carboxyl groups. The fraction of amide groups transformed into carboxyl groups was limited to ~0.5. The characterization and thermal behavior of membranes with different degrees of grafting were evaluated by FTIR, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) measurements. The heat of fusion and the crystallinity of polyethylene decreased considerably in the hydrolyzed membranes depending on the degree of grafting. It was found that the grafting of acrylamide led to the reduction in crystallinity due to disruption of the crystallites (crystal defects) and dilution of the inherent crystallinity (dilution effect). The contribution of the hydrolysis step to the crystallinity decrease was negligible. The thermal stability of the membranes as obtained from TGA showed considerable enhancement after hydrolysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 149–154, 2003  相似文献   
1000.
Numerous applications, from molecular electronics to super‐strong composites, have been suggested for carbon nanotubes. Despite this promise, difficulty in assembling raw carbon nanotubes into functional structures is a deterrent for applications. In contrast, biological materials have evolved to self‐assemble, and the lessons of their self‐assembly can be applied to synthetic materials such as carbon nanotubes. Here we show that single‐walled carbon nanotubes, coated with a designed amphiphilic peptide, can be assembled into ordered hierarchical structures. This novel methodology offers a new route for controlling the physical properties of nanotube systems at all length scales from the nano‐ to the macroscale. Moreover, this technique is not limited to assembling carbon nanotubes, and could be modified to serve as a general procedure for controllably assembling other nanostructures into functional materials.  相似文献   
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