氯乙烯合成转化器影响因素的分析与改进

介绍了氯乙烯合成过程中转化器的使用情况,从转化器的循环用水、催化剂触媒的装载、活化、转化器测温点的设置、转化器通气量以及转化器出现泄漏后的处理等方面进行了分析,从而使转化器的使用效果达到最优化。     

氯乙烯转化器运行情况分析

介绍了乙炔和氯化氢反应制氯乙烯转化器使用前的触媒活化工艺、转化器运行过程中的操作和控制以及转化器热水自循环工艺,分析了氯乙烯转化器损坏的主要原因及应对措施。     

新型转化器在PVC生产中的研究与应用

分别介绍了常规转化器和新型转化器在PVC生产中的运行情况,理论研究和实际运行结果表明,在转化器尺寸和列管数量都不变的情况下,新型转化器单台产能有所提高且触媒使用寿命延长。     

大型转化器在PVC生产中的应用

介绍了3种氯乙烯转化器在PVC生产中的使用情况,总结了小列管转化器的特点,指出了大型化和小列管化是转化器的发展趋势。     

新型氯乙烯转化器的应用实效

汇总新型氯乙烯转化器的实际运行结果。新型转化器与常规转化器比较,单台生产能力可以提高50%以上,节省汞触媒30%以上,为提高转化器产能、降低汞消耗、减少汞污染开辟了一条新途径。采用新型氯乙烯转化器具有极大的社会效益和经济效益。     

焦炉气生产甲醇精脱硫工艺优化改进

分析了天浩公司焦炉气制甲醇精脱硫工艺中存在的问题,介绍了精脱硫工艺的优化改进情况。在不改变精脱硫整体工艺的情况下,将原一级加氢转化器改为预加氢转化器,将原中温脱硫槽C槽改为一级加氢转化器,不仅降低了一级加氢转化器的催化剂的消耗,而且更换一级加氢转化器的催化剂时,不再需要甲醇系统停车,实现了生产的长周期运行。     

氯乙烯转化器腐蚀的原因及对策

介绍了氯乙烯转化器的使用情况,探讨了其腐蚀泄漏原因及影响因素。从转化器的制造、使用、检修等方面提出相应对策来延长转化器使用寿命。     

转化器腐蚀的控制措施

介绍了氯乙烯转化器的使用情况,分析了其腐蚀泄漏原因及影响因素。指出从转化器的制造、使用、检修等方面采取综合措施可延长转化器的使用寿命。     

防止氯乙烯转化器的腐蚀

氯乙烯合成转化器常因原料气干燥不合格,触媒要经常结块,造成转化器渗漏堵塞停产停车的生产被动局面。为此,对转化器使用采取了下述方法,取得一些成效。 (1)严格控制原料气流量稳定 一般转化合成气温度应不超过160℃,以避免转化器列管和管板高温膨胀,使转化器管板处渗漏。 (2)保持HgCl_2触媒的干燥 由于转化器必须定期翻换触媒,因触媒     

浅谈提高单体转化器使用寿命的措施

通过改进氯乙烯转化器结构、重新选材、控制混合气及触媒含水量、维护转化器热水系统，并合理调节单台转化器气体流量等措施，提高了转化器的使用寿命，降低了触媒消耗，提高了氯乙烯单体产量，全年可多获效益270．19万元。     

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。