离子交换膜的维护

介绍离子交换膜的工况。分析盐水中的杂质，阴、阳极液浓度变化，温度。压力对离子交换膜性能和寿命的影响原理。提出维护离子膜的方法有：平稳运行，减少开、停车次数和增加预防控制措施。修复离子膜的方法有停车时循环阳极液、用纯水清洗离子膜或根据实际情况改变运行状态，如离子交换膜受Ca^2 、Mg^2 轻微污染时，先停车再启动；受中度污染时可将阴极液质量分数从32％调整到33％，或将阳极液质量浓度从190g／L升至200g／L，或同时调整阴极液、阳极液浓度。     

离子膜针孔和起泡原因分析及处理措施

分析离子膜边缘区域和膜上部30cm区域产生针孔及起泡的原因为气泡效应、电流密度分布不均等，并找出相应的措施：在修槽时仔细检查和处理毛刺和单元进料管、停车时严格进行阳极液置换及保证操作条件平稳等措施，使自贡鸿鹤化工股份公司氯碱厂的离子膜装置运行29个月后，电流密度升至4．5kA/m^2，其阴极电流效率达到94．69％，平均单元槽压为3．28V，直流电耗为2378kW．h／(t．NaOH)。     

减缓离子膜法电解电流效率下降的方法

分析了离子膜法电解制烧碱过程造成电流效率下降的因素。提出了减缓离子膜法电流效率下降、延长离子膜寿命的方法：保证盐水质量;运转时电流密度接近4．0kA／m^2,氢氧化钠质量分数30％,阳极液中NaCl质量浓度稳定在190～210g／L,并防止纯水供应中断。     

加强管理保证电槽平稳运行

介绍了4万t／a离子膜运行1年多的倩况，指出影响离子膜电槽运行的主要因素有盐水质量、阳极液PH值、电流密度、电槽温度、阳极液浓度、阴极液浓度和槽压差等，认为只有严格管理，遵守操作方法，才能保证离子膜电槽平稳运行。     

离子膜稳定运行的影响因素分析

分析盐水质量、阴极液NaOH浓度、阳极液NaCl浓度、电流密度、阳极液pH值、电解液温度和流量、电解槽压力和压差、开停车及伴生水摩尔量不符合运行指标时,会造成离子膜起泡、针孔,阴、阳极涂层损坏。结合济宁中银电化有限公司的运行实际,强调分析化验的重要性。     

浅析离子膜电解槽电流效率的影响因素

分析了离子膜电解槽电流效率的影响因素,认为保持较高电流效率和较低槽电压要做到：保证盐水质量合格;阴极液中NaOH质量分数32%～35%;阳极液中NaCl质量浓度200～220 g/L;保持电流稳定;严格控制阳极液pH值2～4;生产中不停供纯水或盐水;保持膜操作温度80～90℃.     

离子膜烧碱工艺的淡盐水脱氯

1淡盐水中游离氯及其危害1．1游离氯来源经过一次及二次精制的饱和盐水进入电解槽后有50％～70％被分解，在阳极室内有30％～50％的氯化钠未被分解，成为浓度较低的淡盐水，被电解过程中产生的氯气所饱和，并含有次氯酸钠等盐类。为保证电解槽的阳极液中含有的氯化钠浓度符合电解要求，要连续不断地供给电解槽饱和盐水，同时连续不断地从阳极液中抽出部分淡盐水。从离子膜电解槽的特性及运转过程知道，淡盐水的浓度过低，不仅对提高电流效率、降低碱中含盐量不利，而且还会造成离子膜鼓泡，槽电压升高，电流效率下降；淡盐水浓度过高，离子…     

离子膜装置电流效率下降幅度的改善

通过影响离子膜电流效率的主要因素、离子膜装置存在的问题，来分析离子膜装置电流效率下降幅度改善的措施，主要有：优化盐水质量、开停车次数改善、阳极液中氢氧化钠浓度、氯化钠浓度的控制改善、严格工艺管理和工艺操作等几种有效措施。     

离子膜性能下降因素及危害

离子膜法电解制烧碱的生产过程中，离子膜的性能相对稳定；当离子膜受到盐水杂质，机械损伤，溶胀，收缩及其它因素的影响时，均有可能导致离子膜性能的下降。分析了不同因素可能对膜造成的损伤，介绍了避免这些损伤应采取的预防措施，以及发生损伤后的处理方法。     

离子膜装置阳极气液分离器的技术改造

针对中国石化齐鲁股份公司氯碱厂5万t／a离子膜烧碱装置运行中出现的阳极气液分离器内压力升高的现象。分别进行了100％、80％和120％3个不同负荷下，气相出料管线、液相出料管线和阳极气液分离器的物料衡算，结论是气液分离器规格小，分离空间不足。通过增大气相出料管径，改大气液分离器，使得气液分离器压力由正压变为负压，且气液分离效果好。     

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。