臭氧氧化与海藻酸钠混凝处理微污染水的研究

本文以厦门大学嘉庚学院中区外河流内微污染湖水为处理对象,通过多因素正交实验,研究O_3投加量、O_3氧化时间,海藻酸钠投加量和混凝时间组合工艺对微污染水水质处理效果的影响,以色度、浊度、CODMn和磷酸盐4项指标来判断3种工艺的处理效果。正交试验结果表明,当O_3投加量为0.5mg·L~(-1),O_3氧化时间为25min,海藻酸钠投加量为1.67mg·L~(-1),混凝时间为15min时,臭氧氧化-海藻酸钠混凝组合工艺对色度、浊度、CODMn和磷酸盐的去除率分别达到80.03%、77.32%、68.97%和77.34%。     

臭氧预氧化深度处理微污染水试验研究

以微污染水源水为研究对象,采用臭氧预氧化与常规处理联用工艺对其进行了中试研究。结果表明在臭氧投加量为3.0 mg.L-1,混凝剂投加量为35 mg.L-1,助凝剂投加量为0.7 mg.L-1,该系统对CODMn、色度、浊度有较好的去除效果,出水CODMn、色度、浊度分别低于3.0 mg.L-1、4度、0.8NTU。     

污水处理厂尾水强化混凝沉淀处理工艺

采用投加助凝剂(PAM)、臭氧、粉末活性炭三种强化混凝沉淀工艺处理污水处理厂尾水,通过监测分析尾水处理前后的水质变化,研究助凝剂、臭氧、粉末活性炭对混凝沉淀工艺的强化效果。研究结果表明,混凝剂和助凝剂投加量比值为100:1时,COD_(Cr)、TP和浊度的去除效果明显提高,其中COD_(Cr)去除率比不投加助凝剂时提高将近15%。臭氧预氧化可以明显提高色度、氨氮、UV_(254)等指标的混凝去除效果,当投加5 mg/L的臭氧时,色度、UV_(254)的去除率比不投加臭氧时分别提升26.21%、17.89%。粉末活性炭不宜与混凝剂同时投加,混凝前30～60 min投加适量粉末活性炭(10～20 mg/L),可强化COD_(Cr)、TP和浊度的去除效果。     

粉末活性炭处理微污染水库水试验研究

采用投加粉末活性碳方法处理白石水库微污染水。静态试验采用接触混凝、静沉,现场动态试验采用接触混凝、沉淀、过滤工艺。试验结果表明,投加粉末活性碳、聚合氯化铝和聚丙烯酰胺,可有效降低CODMn浊度和色度。粉末活性炭投量、接触时间及粒度,对净水效果均有显著影响。相关最佳工艺条件为：活性炭投量20mg/L,接触时间30min,粒度0．074～0．147mm。     

磁混凝沉淀技术处理微污染水体研究

采用磁混凝沉淀技术处理微污染河道水,考察了磁粉种类与用量、絮凝剂用量、投药顺序、静沉时间等因素对磁混凝沉淀技术处理效果的影响。结果表明:磁粉种类和药剂投加顺序对微污染水中各污染物的去除效果不同, 4#磁粉表现出较优异的综合性能,磁粉+PAC+PAM的投加方式对污水处理效果最佳。应用磁混凝沉淀技术处理微污染河道水,提高了对污水中SS、 TP、 COD的去除效果,当磁粉投加量为100 mg/L, PAC投加量为60 mg/L, PAM投加量为1.0 mg/L时, SS、 TP、 COD的去除率分别可达到94.6%、 84.9%和40.7%。采用该技术能有效缩短絮凝与沉降时间,且更易于实现固液磁分离。     

臭氧协同活性炭纤维与硫酸铝混凝处理微污染源水研究

以受污染的桂林两江四湖水为研究对象,通过静态试验确定其适宜的臭氧、活性炭纤维和硫酸铝的投加量.当预臭氧投加量为2～2.5 mg·L-1时,臭氧与水接触时间为10 min,ACF与A12(SO4)3联合投加于试验用水中,浊度、UV254、CODMn的去除效果均好于单独投加ACF.试验结果表明,投加的臭氧.ACF与A12(SO4)3之间很有可能发生了协同作用.从经济角度考虑,投加ACF量在40～50 mg·L-1之间较为合适.常规工艺去除微污染源水中有机污染物效果有限,因此臭氧顸氧化结合混凝工艺能够解决传统工艺不能解决的问题.该预处理工艺具有处理成本低、处理效果好等优点,它作为微污染源水预处理技术有其良好的应用前景.     

臭氧预氧化工艺对原水处理效果的中试

以南方某水厂原水为对象,开展臭氧预氧化工艺中试研究。结果表明,臭氧预氧化能够明显降低常规工艺出水色度,对有机物的去除效果不明显,但能够协助提高混凝沉淀工艺对浊度、色度和CODMn等污染物的去除能力。从经济和净水效果角度综合而言,预臭氧化最佳投加量为0.5～1.0 mg/L。     

混凝法处理低温高浊度原水的适应性研究

混凝法能有效地去除水中的胶体颗粒物,降低水的浊度,在城镇水厂生产中应用广泛。本文主要论述了不同的反应条件对混凝法处理低温高浊度原水的影响。通过烧杯搅拌试验得出:当1%的聚合氯化铝(PAC)的投加量为0.5 m L/L,生石灰的投加量为15 mg/L时,混凝沉淀处理效果最佳,沉淀后源水浊度降至1.44 NTU。     

混凝沉淀对污水处理厂二级出水的处理效果

采用混凝沉淀工艺处理污水处理厂二级出水,通过投加聚合氯化铝(PAC)和聚硫氯化铝(PASC)混凝剂,分析混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、氨氮、总氮、总磷等指标的去除效果,并找到最佳的处理试剂及投加量。结果表明,混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、总磷具有很好的去除效果,氨氮和总氮的去除效果不佳,投加混凝剂会增加二级出水离子含量,导致电导率增加。聚硫氯化铝的混凝效果较聚合氯化铝好,对于有机物、色度等指标,达到相同混凝效果,聚硫氯化铝投加量仅约聚合氯化铝的一半,两者的最佳投加量分别为40 mg/L和80 mg/L。     

混凝沉淀对污水处理厂二级出水的处理效果

采用混凝沉淀工艺处理污水处理厂二级出水,通过投加聚合氯化铝(PAC)和聚硫氯化铝(PASC)混凝剂,分析混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、氨氮、总氮、总磷等指标的去除效果,并找到最佳的处理试剂及投加量。结果表明,混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、总磷具有很好的去除效果,氨氮和总氮的去除效果不佳,投加混凝剂会增加二级出水离子含量,导致电导率增加。聚硫氯化铝的混凝效果较聚合氯化铝好,对于有机物、色度等指标,达到相同混凝效果,聚硫氯化铝投加量仅约聚合氯化铝的一半,两者的最佳投加量分别为40 mg/L和80 mg/L。     

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.     

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。     

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.