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固体氧化物燃料电池材料的研究进展   总被引:24,自引:3,他引:21  
本文对燃料电池的研究发展进行了概述,详细地介绍了固体氧化物燃料电池的电解质材料、阳极材料、阳极材料及互连材料,并对固体氧化物燃料电池以后的发展提出了一些建议。  相似文献   

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概述了功能材料的基本性能和用途,从功能金属材料、功能无机非金属材料、功能高分子材料、功能晶体材料、功能复合材料、具有特殊结构的功能材料(非晶态合金-金属玻璃、纳米结构材料、贮氢材料、薄膜功能材料、形状记忆材料、智能材料与结构、减震材料、生物医学材料)等方面进行了分类和描述。功能材料种类繁多,用途广泛,在工农业生产和科学技术等领域起着非常重要的作用。  相似文献   

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我们知道,世界是由物质构成的,一切物质都是由单质和各种不同的化合物组成的;而化合物又是由无数个分子组成的。人们通常把分子量只有几十到几百的化合物称为低分子化合物,而把分子量达到几万、几十万,甚至几百万的称为高分子化合物。象蛋白质、纤维素等都属于天然高分子。目前人类已经采用化学方法,人工制造高分子,故称合成高  相似文献   

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气体膜分离技术的应用及发展前景   总被引:10,自引:1,他引:9  
介绍了适用于气体分离的各种材料,并着重介绍气体膜分离技术在各领域的应用实例,如天然气中H2S的脱除及油田CO2回收利用,医用氧,空气和水蒸气的分离,从炼厂气中回收氢气等等,最后预测分析了我国气体膜分离技术的发展方向。  相似文献   

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综述了国外功能高分子四大领域(电磁功能,光功能,生物医用,分离材料和化学功能0的发展概况,分析了国外功能高分子材料的研究开发方向,并根据我国功能高分子材料的开发现状提出了建议。  相似文献   

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张亨 《中国氯碱》2003,(11):23-25
介绍了PVC功能材料的功能化原理和加工方法。概括了医用PVC功能材料、抗静电PVC材料、导电PVC材料、PVC磁性材料和PVC离子交换膜材料的制备方法和应用情况。展望了PVC功能材料的应用前景。  相似文献   

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新技术在高分子材料科学与工程中的应用(摘要)   总被引:2,自引:0,他引:2  
徐僖 《化工进展》1995,(4):10-11
目前三大合成高分子材料的世界年产量早已超过1亿t,预计今年将达到1.5亿t,2000年将达到1.8亿t,发展十分迅速,已成为国民经济和科技领域不可缺少的重要材料。在学科方面,高分子材料与金属材料和无机非金属材料并驾齐驱,在国际上早已被列为一级学科。我国三大合成材料目前年产量和人均消费量均远低于发达国家的水平。我们科技工作者面临的任务十分艰巨,既要为加快发展我国高分子材料工业服务,又要积极为高新技术的突破提供有关的关键材料,攀登“通用高分子材料的工程化和工程高分子材料高性能化”两大高峰。新材料是高新技术发展的先…  相似文献   

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本文结合生产实际,简要阐述了制造单位在压力容器制造过程中经常发生的一些材料代用情况及处理方法,以及一些特殊情况代料的注意事项。  相似文献   

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Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

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A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by 1H MAS NMR. For direct comparison purposes, an SiO2 coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N2 absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.  相似文献   

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Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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