四氯化硅的氢化处理技术进展

改良西门子法多晶硅生产工艺会产生大量的四氯化硅有害气体,为了减少对环境污染,降低生产成本,需要对四氯化硅进行合理利用。通过氢化手段将四氯化硅转化为三氯氢硅能使四氯化硅得到合理有效的利用。本文重点介绍了目前主流的热氢化、冷氢化、氯氢化、等离子体氢化、催化氢化等五种四氯化硅氢化处理技术的工艺特点和研究进展,并对各种技术特点进行了评价。     

二氯二氢硅综合应用研究进展

详述了二氯二氢硅与四氯化硅进行反歧化反应制备三氯氢硅技术的研究进展,简述了二氯二氢硅在制备多晶硅、硅烷气、多晶硅薄膜、氮化硅薄膜和二氧化硅薄膜中的应用。     

四氯化硅氢化制备三氯氢硅的研究进展

综述了多晶硅副产物四氯化硅的处理方法,将四氯化硅氢化制备三氯氢硅是最有效的方法,此方法不仅处理掉了四氯化硅,同时生成了多晶硅生产的原料三氯氢硅,大幅的降低了生产成本。重点介绍了四氯化硅的氢化,包括热氢化、冷氢化与等离子体氢化三种方法。     

四氯化硅催化氢化及其催化剂研究进展

综述了四氯化硅氢化制备三氯氢硅的催化方法,重点介绍了四氯化硅催化氢化的机理及其催化剂进展情况,并对四氯化硅催化氢化进行了展望。     

四氯化硅氢化生产三氯氢硅技术研究

四氯化硅氢化生产三氯氢硅技术的应用能有效处理多晶硅生产线产生的大量四氯化硅,从而极大降低多晶硅的生产成本,实现工业硅粉制备高纯多晶硅的工艺闭路循环,因此提升四氯化硅的转化率,进而降低企业经济成本是一项重要研究内容。以四氯化硅氢化生产三氯氢硅为主要内容,结合实际生产过程,从工艺流程、反应原理和影响因素三个方面详细分析了四氯化硅氢化生产三氯氢硅的流程,进而展现出该技术中的优势和劣势,促进企业对相关技术研究的进一步深入。     

四氯化硅等离子体氢化技术研究进展

改良西门子法是生产多晶硅的主流工艺, 四氯化硅的氢化技术是其改良的关键。传统的热氢化和冷氢化方法存在着能耗高和转化率低的缺点。本文介绍了四氯化硅制备三氯氢硅的等离子体氢化技术, 概述了热等离子氢化方法, 主要包括直流放电等离子体法、高压射频等离子体法、低压射频等离子体法、微波等离子体法等, 简述了冷等离子氢化方法, 并对介质阻挡放电等离子体法进行了介绍和实验探索。对各种等离子体氢化方法进行了综合性的分类和分析讨论, 指出了现存各方法的优缺点, 提出了等离子氢化技术在工业化时的关键难题, 并对各种方法的应用前景进行了展望。     

四氯化硅综合利用的现状及发展趋势

介绍了西门子法多晶硅的副产物四氯化硅的综合利用技术及其现状,目前,四氯化硅主要用来制备气相白炭黑、硅酸乙酯、光纤、多晶硅及三氯氢硅等,重点介绍了国内外四氯化硅氢化技术的最新进展。     

四氯化硅氢化技术进展

四氯化硅作为西门法高纯多晶硅生产中产量最大的副产物,是一种具有强腐蚀性的毒害物质。目前,国内多晶硅的大规模生产即将兴起,解决其副产物四氯化硅的最有效的方法是转化为三氯氢硅。着重介绍了热氢化、冷氢化、氯氢化、等离子体氢化等国内外四氯化硅氢化技术的工艺特点和研究进展。     

四氯化硅转化技术的现状与发展趋势

介绍以四氯化硅为原料生产的几种化学产品（气相法白炭黑、硅酸乙酯、多晶硅、光纤材料、三氯氢硅）的生产技术的现状和发展趋势,并分析这些产品的市场容量和对消耗四氯化硅所起的作用。国内多晶硅的大规模生产即将兴起,解决其副产物四氯化硅的最有效的方法是转化为三氯氢硅。着重介绍国内外四氯化硅氢化技术,及笔者正在开发的等离子体四氯化硅还原新工艺。     

电子级多晶硅生产技术探讨

介绍了目前国内外电子级多晶硅生产技术的发展状况,重点说明了改良西门子法电子级多晶生产技术原理及其工艺流程,主要包括:氢气制备及纯化、氯化氢合成、低压氯化(三氯氢硅合成)、低温氢化(四氯化硅转化)、精馏、CVD还原、尾气回收和后处理等工序。结合电子级多晶硅生产技术的成功工程应用实践,介绍了电子级多晶硅项目的技术特点。     

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。