臭氧氧化及活性炭吸附处理黄河水试验研究

以黄河水为研究对象,考察臭氧氧化降解和活性炭吸附去除水中有机污染物的效能.结果表明,在臭氧投加量为1～3 mg·L-1时,CODMn的去除率由8％升高到20％,之后其变化不明显;UV254的去除率由9％升高到30％,此时臭氧即可以将不饱和有机物大量去除.臭氧投加量为1～2 mg·L-1时,短时、大强度曝气,其出水CODMn和UV254的去除效果较好.高臭氧投加量时,增加曝气接触时间可以提高臭氧对有机物的去除率,出水效果较好.在活性炭投量为10 mg· L-1,pH为8.3,水温为45℃,臭氧投加量为3 mg·L-1时,活性炭对黄河水的吸附效果较理想.臭氧氧化对黄河水中TOC的去除效果低于CODMn和UV254的去除效果,当臭氧投加量为8 mg·L-1时,TOC去除率才为10％.但是臭氧投加量为5mg· L-1,BDOC提高了80％.因此臭氧氧化可以大幅度提高原水的可生物降解性,为后续生物处理提供有机营养物质条件.     

预氯化与强化混凝相结合用于给水处理的试验

试验研究了氯化时间、有效氯投加量等因素对次氯酸钠氯化效果的影响,以及氯化与混凝的先后顺序对CODMn及UV254去除效果的影响。结果表明,对本试验原水,有效氯投加量为4mg/L,经过30min氯化后,CODMn去除率达20%左右,再经过强化混凝后,CODMn去除率可达50%左右。先氯化后混凝对于CODMn的去除效果总体要优于先混凝后氯化。在低投氯量时,先混凝后氯化对于UV254的去除效果优于先氯化后混凝,但随着投氯量的增加二者的处理效果相当。     

微污染原水的膨润土/粉末活性炭和MBR组合工艺处理技术

以膨润土、粉末活性炭(PAC)为吸附剂,考察了其对微污染物(NH3-N、UV254)的去除效果。通过改变膨润土/PAC的投加量,考察了其与MBR的组合工艺对氨氮与UV254的去除效果及微生物活性、膜比通量和出水中有机物残留颗粒粒径的影响。结果表明膨润土对UV254的吸附能力弱,平均去除率仅为20.02%,而PAC对UV254的去除率可达89.68%。膨润土-MBR能有效去除NH3-N,平均去除率达92.8%,但对UV254的去除率仅为51.13%;PAC与MBR联用能有效去除NH3-N、UV254,去除率分别为94.5%、89.55%。出水中有机物残留颗粒物不仅数量少,颗粒粒径分布范围也变窄,大粒径颗粒绝大多数得到去除。     

夏季滦河水预氧化中试研究

本试验通过对比两种预氧化剂对夏季滦河水的藻类、CODMn、UV254、TOC等指标的去除效果,分析水中分子量的分布情况,研究了高锰酸钾和氯预氧化对有机物的去除效果。结果表明,KMnO4预氧化在去除有机污染物方面的效果要好于预氯化的处理效果;高锰酸钾预氧化的UV254去除率为23．4％,而TOC去除率为7．1％,说明一部分UV吸收性有机物在预氧化过程中转变为UV非吸收陛有机物,低高锰酸钾投量条件下水中有机物不能得到完全去除。     

后置臭氧-下向流活性炭工艺中臭氧投加量的中试优化

为实现采取"后置臭氧-下向流活性炭"工艺的金泽水厂中臭氧投加量的优化,依托中试装置研究了臭氧投加量对各构筑物处理效率的影响,并采用中心复合设计的(CCD)响应面模型优化了臭氧投加,同时,简析了该工艺对金泽原水中常见微污染物的处理效果.试验结果表明,水中UV254的去除主要发生在臭氧接触、混凝沉淀及活性炭单元,而高锰酸盐指数(CODMn)及总有机碳(TOC)的去除主要发生在混凝沉淀及活性炭单元.臭氧投加量的增加可提高臭氧接触池对有机物的去除效率,但过高的臭氧投加量不利于混凝沉淀及活性炭单元对有机物的去除.通过响应面模型预测了活性炭滤池出水中CODMn去除率最优值为65.4％,此时预臭氧及后臭氧投加量分别为1.02、1.36 mg/L.该工艺对金泽原水中常见抗生素及除去1,4-二氯苯、乙苯外的致嗅物质有较高去除率.     

生物活性炭深度处理工艺挂膜研究

利用中试装置对生物活性炭深度处理工艺的动态培养自然挂膜过程进行研究,讨论了挂膜过程中污染物去除效果的变化,试验显示挂膜期间炭柱对氨氮的去除率与进水氨氮质量浓度可拟合成二次曲线的关系,进水氨氮质量浓度为0.76mg/L时氨氮去除率最高;炭柱对CODMn和UV254的平均去除率分别为32.07%和44.76%;对有机物去除的相关性进行分析显示,挂膜期间中炭柱CODMn和UV254进水浓度和去除量之间相关性分别达0.72和0.71;最后提出以CODMn和UV254的去除率作为判断生物活性炭工艺生物膜成熟的标志以及相关的参数。     

滤池前端投加粉末活性炭工艺的水处理效果研究

考察滤池前端投加粉末活性炭（PAC）T艺的水处理效果,模拟其他位置投加PAC时去除水中有机物的情况,并与滤池前端投加PAC工艺的去除效率进行比较。实验结果说明：在滤池前端投加适量的PAC可以将过滤对COD‰、UV254的去除率提高20％以上,CODMn、UV254平均去除率约为26％、27％;滤池前端投加10mg／LPAC时,沉淀、过滤两个过程对CODMn、UV254的总去除率分别约为40％、55％,与混凝过程投加15mg／I。PAC时取得的效果相当,说明滤池前端投加PAC能更好地发挥其吸附作用,利用效率更高。     

次氯酸钠预氧化处理微污染水源水的试验

通过静态试验,分别研究了氧化时间、水温、氧化剂投加量等因素对次氯酸钠预氧化效果的影响。试验结果表明,在原水水质pH值为7.8～8.2,浊度为6.0～18.0NTU,CODMn的质量浓度为4.2～6.7mg/L,UV254值为0.094～0.141,水温为6.0～15.0℃时,次氯酸钠投加量12.5mg/L,经20min氧化后,CODMn去除率达到25%左右,再经过混凝沉淀后,CODMn去除率达60%左右。     

臭氧联合混凝去除长江源水中有机污染物的小试研究

以长江重庆段水质为研究对象,考察臭氧对混凝去除水中有机污染物的影响。结果表明,臭氧预氧化后,TOC、UV254的去除率分别为2.5%、11.0%,说明臭氧可以部分彻底氧化去除水中有机物,预氧化后有机物的结构改变比较明显;相比于单独混凝,臭氧联合混凝使TOC和UV254的去除率分别提高了4.9～5.3和12.1～14.2个百分点,臭氧预氧化可以强化混凝对TOC和UV254的去除;臭氧预氧后各个分子段有机物的分布改变比较明显,相对分子质量大于3×103的有机物明显减少,相对分子质量小于3×103的有机物明显增加。相比于单独混凝,臭氧联合混凝主要提高了相对分子质量大于3×103的有机物去除率,降低了相对分子质量小于3×103有机物的去除率。     

臭氧活性炭联合工艺去除微污染水中有机物

采用臭氧活性炭联合工艺(O3+BAC)对以长江为水源的某水厂砂滤水进行深度处理。试验结果表明,该工艺对水中有机物有稳定的去除效果,在臭氧投加量为1mg/L,活性炭空床接触时间为8.6min时,对CODMn,UV254,DOC,THMEP(三氯甲烷生成势)和AOC(可同化有机碳)的平均去除率分别为32%,40%,22%,19%,7%。在DOC较低的情况下,三氯甲烷生成势与UV254有较好的正相关性。     

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。