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1.
综述了三维有序大孔(3DOM)炭材料的制备及应用.3DOM炭材料的制备方法主要有胶晶模板法、炭气凝胶法、聚合物热解法,其中胶晶模板法是最有效的方法.还归纳了3DOM炭材料在光子晶体、电极材料、催化剂及催化剂载体、生物材料以及模板等方面的应用研究.  相似文献   

2.
从载体修饰、助剂添加、制备方法和催化剂的失活与再生等方面对乙炔氢氯化炭负载金催化剂的研究现状进行了综述,分析了炭载金催化剂产业化存在的问题,展望了金催化剂在乙炔氢氯化反应中应用的前景,为新一代乙炔氢氯化反应无汞催化剂的开发提供参考。  相似文献   

3.
碳元素是一切有机生命体的骨架元素,由其演变而成的炭材料具有多样性,一直以来都备受研究。炭材料来源广泛,具备高比表面积、发达孔隙结构以及良好热-化学稳定性等特征。因此,被广泛运用于催化、吸附和分离等诸多领域。尤其是作为催化剂载体,在很多反应中都展现出优异的性能。然而传统催化剂的形态限制了其在多相连续反应中的应用,对此,有学者尝试将炭材料与整体式框架结构有机结合。制备得到的新型炭涂层型整体式催化剂,有效地弥补了传统催化剂形态上的缺陷,进一步拓宽了其应用范围。基于此,将对炭涂层型整体式催化剂的制备方法和研究现状进行阐述,详细介绍该催化剂的实际应用效果以及影响其性能的相关因素,最后对炭涂层型整体式催化剂的研究前景进行展望。  相似文献   

4.
碳元素是一切有机生命体的骨架元素,由其演变而成的炭材料具有多样性,一直以来都备受研究。炭材料来源广泛,具备高比表面积、发达孔隙结构以及良好热-化学稳定性等特征。因此,被广泛运用于催化、吸附和分离等诸多领域。尤其是作为催化剂载体,在很多反应中都展现出优异的性能。然而传统催化剂的形态限制了其在多相连续反应中的应用,对此,有学者尝试将炭材料与整体式框架结构有机结合。制备得到的新型炭涂层型整体式催化剂,有效地弥补了传统催化剂形态上的缺陷,进一步拓宽了其应用范围。基于此,将对炭涂层型整体式催化剂的制备方法和研究现状进行阐述,详细介绍该催化剂的实际应用效果以及影响其性能的相关因素,最后对炭涂层型整体式催化剂的研究前景进行展望。  相似文献   

5.
如何有效地催化转化合成气制备过程中所产生的焦油在国内外已被广泛研究。作为对焦油转化具有催化作用的炭及炭载催化剂也受到许多研究者的关注。总结了炭或炭载催化剂的研究现状,分析了影响该类催化作用的主要因素,同时提出了今后在炭及炭载催化剂催化转化焦油方面应进行的研究工作。  相似文献   

6.
木质素是一种具有三维网状分子结构、含有大量芳香基团和高含碳量等特点的天然高分子,其在制备多孔炭领域具有巨大潜力。多孔炭在催化剂和能源储存领域具有极大的应用前景。以来源于制浆造纸和生物炼制行业的副产物工业木质素作为原料制备多孔炭应用于能源储存、吸附、催化剂载体等领域,可实现工业木质素在碳基功能材料领域的高附加值循环再利用。本文详细综述了目前木质素多孔炭的常用制备方法和微结构特性的调控方法,总结归纳了各制备方法的主要特点以及影响木质素多孔炭微结构与性能的关键因素;重点综述了近些年对木质素多孔炭孔道结构调控方面的研究,归纳了孔调控的方法;此外,总结了木质素多孔炭在超级电容器、锂离子电池、吸附剂和催化剂载体领域中的应用研究现状,讨论了催化和储能材料对木质素多孔炭的微结构特性要求。总结并展望了木质素多孔炭在制备与应用中面临的机遇和挑战。  相似文献   

7.
芳环加氢反应是最重要的合成反应之一,钌炭催化剂在芳环加氢反应中具有优异的催化性能。综述钌炭催化剂的制备方法和载体性质对钌炭催化剂的影响以及钌炭催化剂在苯、苯甲酸和对苯二甲酸二甲酯等芳环加氢反应中的应用进展。负载型钌炭催化剂的制备方法主要有浸渍法、沉淀法和升华法,超声辅助浸渍法可将大部分钌纳米粒子引入到炭载体的孔道内部,得到限域型负载钌炭催化剂。而镶嵌式钌炭催化剂主要是指通过原位炭化的方法将钌粒子部分镶嵌在炭的孔壁上,一步得到钌炭催化剂,其制备方法主要有软模板剂法和硬模板剂法。除制备方法外,炭的骨架结构、表面性质及氮掺杂对钌炭催化剂的性能影响也较大。镶嵌式钌炭催化剂具有钌纳米粒子和炭载体之间的相互作用强、催化剂抗流失及烧结性能好,在芳环加氢反应中表现出卓越的催化性能和稳定性。随着新制备技术的出现,新型镶嵌式钌炭催化剂将可能实现产业化。  相似文献   

8.
以铜-铅螯合物为活性组分,介孔炭为载体,采用反应沉淀制备了铜-铅-炭复合燃速催化剂.通过N2吸附-脱附、SEM、TG和DSC等对其进行表征.结果表明,铜-铅螯合物呈不规则球形,铜铅-炭复合催化剂呈球花状.BET比表面积为28 m2/g,孔容为0.012 cm3/g.在20 MPa压强下含铜-铅-炭复合催化剂的双基推进剂...  相似文献   

9.
炭材料作为电催化剂载体在PEMFC中的应用   总被引:1,自引:0,他引:1  
贾荣利  王成扬 《化工进展》2004,23(9):943-947
综述了电催化剂炭载体材料的研究进展,内容包括炭载体对电催化剂以及质子交换膜燃料电池(PEMFC)性能的影响,和一些其他炭材料(除炭黑外)在电催化剂载体中的应用。  相似文献   

10.
将磺酸基团引入到固体载体表面制备磺酸型固体酸以替代传统的硫酸催化剂.对磺酸型固体酸催化剂的制备和应用研究进展进行了综述.介绍了在中孔硅分子筛(如MCM-41、SBA-15)、中孔炭分子筛(如CMK-3、CMK-5)、半炭化炭材料、炭纳米管等载体上引入磺酸基团的方法和其中一些催化剂的催化性能,探讨这些制备方法和所制得催化材料的优点和存在的问题.  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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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   

17.
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   

18.
Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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