活性炭固载杂多酸催化剂的研究现状

杂多酸是一类同时具有酸催化特性和氧化一还原能力的催化剂，有着广泛的应用前景。杂多酸固载化后，能够在液相氧化和酸催化反应中把催化剂从反应介质中很方便地分离出来，且能使这类均相催化反应多相化。本文介绍了以活性炭为载体的固载型杂多酸催化剂的研究状况，包括制备方法、影响负载量的因素及负载量对催化性能的影响，文章同时阐述了有关活性炭固载杂多酸的机理分析，总结了近年来活性炭固载杂多酸催化剂的应用研究及进展。     

活性炭固载杂多酸催化合成乙酸丁酯的研究

在液-固反应体系中研究了固载在几种国产活性炭上具有Keggin结构的杂多酸对乙酸和正丁醇酯化反应的催化性能,结果表明,催化剂具有较高的酸催化活性和选择性,不同活性炭对杂酸的固载牢度显著不同。负载杂多酸的催化活性以及溶脱量与氨-TPD的研究结果是一致的。     

固载杂多酸催化剂应用进展

固载型杂多酸作为一类新型固体酸催化材料，与传统的质子酸催化剂相比，其优点突出，已应用于炼油技术、化工和精细化学品的合成领域。文章对固载型杂多酸催化剂的重要性质和近年来的应用研究及进展进行了综述。     

专利文摘

<正>一种双亲性钒取代Keggin型杂多酸脱硫催化剂申请号:201610234173.9申请日:2016-04-17申请人:东北师范大学该专利涉及一种双亲性钒取代Keggin型杂多酸脱硫催化剂,属于功能催化材料的制备和催化脱硫技术领域,其特征在于采用具有一定碳链长度的阳离子表面活性剂和钒一     

固载杂多酸催化剂研究进展

固载型杂多酸作为一类新型固体酸催化材料,与传统的质子酸催化剂相比,其优点突出,已应用于炼油技术、化工和精细化学品的合成领域.文章对固载型杂多酸催化剂的重要性质和近年来的应用研究进展进行综述.     

负载型杂多酸催化剂的制备及其对催化合成乙酸异丙酯的性能研究

采用热回流浸渍法将Keggin型12-磷钨杂多酸负载到改性高岭土上,并利用X射线衍射(XRD)、傅立叶变换红外光谱(FT-IR)、扫描电子显微镜(SEM)等手段对催化剂进行了表征。考察了负载型磷钨杂多酸催化剂对乙酸、异丙醇催化合成乙酸异丙酯的最佳反应条件。结果表明:改性高岭土有助于磷钨酸更好的分散,负载后磷钨杂多酸的Keggin结构并未遭到破坏。所制备的催化剂对乙酸和异丙醇合成乙酸异丙酯的酯化反应具有很好的催化选择性。     

杂多酸的固载化及其酸催化研究进展

固载杂多酸作为新型固体酸催化材料,与传统的质子酸催化剂相比,其优点突出,在化工领域得到广泛应用。从杂多酸和载体的一些特性研究了几种典型的固载杂多酸催化剂,并对其性能、在催化领域中的应用及其发展前景进行了综述。     

负载型杂多酸催化剂的研究进展

负载型杂多酸作为一类新型固体酸催化材料,其合理利用不仅可以有效提高催化活性和选择性,而且减少了设备腐蚀和环境污染,且易于回收利用。本文着重综述了近年来活性炭、S iO2、MCM-41分子筛等各种负载型杂多酸催化剂的研究成果和动态,包括所涉及的反应物系、反应机理、催化性能与催化剂酸性质的关系等。最后通过负载型杂多酸催化剂目前存在的问题,展望了其今后的研究方向和重点。     

杂多酸-聚合物复合膜催化合成丙烯酸-2-甲氧基乙酯

制备了Keggin型磷钨酸-乙烯醇复合膜催化剂,用FT-IR等分析方法对催化剂进行了表征。以该复合膜催化合成丙烯酸-2-甲氧基乙酯作为探针反应,考察了反应物配比、催化剂用量、反应时间及催化剂重复使用次数对催化剂活性的影响。研究发现,该固载型杂多酸催化剂对丙烯酸-2-甲氧基乙酯合成具有较高的催化活性,此类聚合物固载型杂多酸采用有机无机复合的方式形成,具有制备简单、催化活性较高、可再生、催化剂易回收等优点。在最佳反应条件下,丙烯酸-2-甲氧基乙酯的收率可达到95.4%以上。     

介孔分子筛固载Keggin结构钼钨磷杂多酸的制备及表征

用萃取法合成了两种 Keggin结构的钼钨磷杂多酸 ,用水热法制取了 AIMCM- 41介孔分子筛 ,经离子交换制成 HAIMCM- 41 ;浸渍法制取固载型 HPA/ HAIMCM- 41催化剂。用 IR、XRD对其结构和性能进行了表征。结果表明合成的 HPA具有典型的 Keggin结构而 HAIMCM- 41具有典型的介孔性质 ,固载后 HPA的 Keggin结构基本保持     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。