聚二甲基二烯丙基氯化铵对聚合硫酸铁处理冬季长江水的助凝效果

采用聚二甲基二烯丙基氯化铵(PDM)与聚合硫酸铁(PFS)复合制得的稳定型复合混凝剂,用于冬季低温长江水强化混凝脱浊处理。通过混凝烧杯试验,考察了PDM对PFS在脱浊效果和沉淀性能上的改进程度。结果表明:对温度为5～7℃,浊度为45 NTU左右的冬季长江水,PDM助凝效果明显,同时PFS与PDM的复配比例越低,复合混凝剂混凝脱浊效果越好。复合混凝剂中PFS的用量比单独使用PFS时的少。复合混凝剂能增大絮团的沉淀速度,克服冬季低温条件下单独使用PFS时絮体轻而细小、沉淀慢、破碎现象严重的问题,从而使沉淀出水水质能够迅速稳定地达标,同时,还可明显改善PFS处理时出水带色、腐蚀设备等问题。     

PDM复合PFS用于夏季长江水强化混凝脱浊处理

采用聚二甲基二烯丙基氯化铵(PDM)与聚合硫酸铁(PFS)复合制得稳定型复合混凝剂,用于夏季长江水强化混凝脱浊处理.通过混凝烧杯试验,考察了PDM在脱浊效果及沉淀性能上对PFS的改进程度.结果表明,对温度为28～30℃、浊度为110～120NTU的夏季长江水,复合药剂脱浊效果明显,PFS/PDM复合配比越低,复合混凝剂混凝脱浊效果越好;达到南京某水厂6 NTU的沉淀出水余浊标准时,沉淀30 min,PFS需3.45 mg·L-1的投加量,PFS与特征黏度分别为0.55,1.53、2.47 dL·g-1的PDM以20∶1,10∶1,5∶1的配比复合的复合药剂分别需要约3.04～3.17 mg·L-1、2.97～3.03 mg·L-1、2.51～2.65 mg·L-1左右的PFS投加量,相对于PFS单独处理分别约能减少投加量8.1%～11.9%、12.2%～13.9%、23.2%～27.2%,可明显改善PFS投加量大时出水带色,腐蚀设备和管道的缺点.PFS/PDM复合药剂混凝产生絮团大,沉淀快,在相对较短的时间内可使沉淀出水余浊达到标准,在夏季长江水实际生产中可增大现有设备的制水能力,可作为缓解夏季城市供水不足的一个手段.     

复合聚铝处理秋季长江水脱浊研究

通过混凝烧杯实验,探讨了特征黏度系列化的聚二甲基二烯丙基氯化铵(PDM)与液体聚合氯化铝(PAC)复合得到的稳定型复合混凝剂用于对秋季微污染长江水强化混凝处理效果。结果表明,对温度为16～18℃,浊度为70 NTU左右的秋季长江水,沉淀池出水在达到6 NTU的南京某水厂现行浊度标准的情况下,PAC需1.66mg/L的投加量,质量配比分别为20∶1、10∶1、5∶1的PAC(以Al2O3计)/PDM复合混凝剂所需投加量随特征黏度变化为1.38～1.26、1.19～1.14、1.16～1.13 mg/L,相对于PAC可减少投加量16.87%～24.10%、28.31%～31.32%、30.12%～31.93%。复合混凝剂还提高了絮体密实度与沉淀性能。由此可见,PDM明显改善了PAC的混凝脱浊效果,PAC/PDM复合比例越低,PDM特征黏度越高,脱浊效果与沉淀性能越好。考虑未来社会对水质的要求,若使沉淀池出水达到2 NTU左右,则PAC需3.35 mg/L左右的投加量,而复合比例分别为20∶1、10∶1、5∶1的复合混凝剂仍能比单独使用PAC减少19.10%～30.45%的投加量。     

PDM复合混凝剂用于低温低浊水源水处理的研究——低浊度宁波姚江水处理

该文报道了用特征黏度系列化的有机阳离子高分子聚二甲基二烯丙基氯化铵(PDM)与无机混凝剂复合物对宁波低浊度姚江水的脱浊处理研究过程。通过混凝烧杯实验,考察了无机混凝剂的种类及其与PDM的复合配比对低浊度姚江水脱浊效果的影响。结果表明,对低浊度姚江水,要达到1.0~1.2 NTU的沉淀出水余浊,硫酸铝(AS)需5 mg/L左右的投加量,聚合硫酸铁(PFS)需8 mg/L左右的投加量,而聚合氯化铝(PAC)的投加量在10 mg/L左右;PDM对无机混凝剂强化混凝脱浊效果明显,无机混凝剂与PDM的复合配比越低,复合混凝剂混凝脱浊效果越好,在达到水厂沉淀出水浊度标准的前提下,AS/PDM复合药剂能比单独使用AS减少20%AS投加量;PFS/PDM复合药剂能比单独使用PFS减少30%~40%PFS投加量;PAC/PDM复合药剂能比单独使用PAC减少30%~50%PAC投加量。     

PFS-PDM复合混凝剂对东江水源水净化处理及其混凝性能研究

将聚二甲基二烯丙基氯化铵(PDMDAAC)与聚合硫酸铁(PFS)复合制备了新型复合混凝剂PFS-PDMDAAC(PFS-PDM),对秋冬季东江微污染水源水强化混凝净化处理,并采用红外光谱、扫描电镜、Zeta电位对复合混凝剂的形态和性能进行初步表征。结果表明,复合混凝剂PFS-PDM在浊度、UV_(254)及CODMn去除效果都优于单独使用PFS或PDM,PFS-PDM并不是PFS和PDM简单机械混合,而是形成新的结构,复合混凝剂PDM含量及盐基度对混凝性能影响与Zeta电位相关。     

低温低浊河网水的有机高分子助凝处理研究

用不同特征黏度的聚二甲基二烯丙基氯化铵(PDM)与聚合氯化铝(PAC)、两种市售无机复合聚铝分别复合,用以改进无机混凝剂对低温低浊微污染河网水的混凝脱浊效果。考察了无机混凝剂的种类及其与PDM的复合配比对低温低浊微污染河网水脱浊效果的影响。结果表明,对温度为7～10℃,浊度为4.5～8NTU的低温低浊河网水,在与实际生产相近的混凝搅拌强度下,要达到2NTU左右的出水余浊标准,PAC、复合聚铝1、复合聚铝2分别需4.0、3.5、2.8mg/L的投加量。而用特征黏度分别为0.52、1.47、2.46 dL/g的PDM配制的、无机复合聚铝与PDM复合质量比为20:1、10:1、5:1的复合混凝剂PAC/PDM、复合聚铝1/PDM、复合聚铝2/PDM,比单独使用同种无机混凝剂,分别约能减少10%～25%、8.6%～28.6%、7.1%～28.6%的无机药剂投加量,无机复合聚铝与PDM复合比例越低、PDM特征黏度越高,复合混凝剂脱浊效果越好。因此,PDM对低温低浊河网水具有明显的强化混凝脱浊效果。     

复合硫酸铝用于冬季太湖水的混凝脱浊研究

用特征黏度系列化的聚二甲基二烯丙基氯化铵(PDM)与硫酸铝(AS)复配制得稳定的复合混凝剂,用于冬季低温太湖水强化混凝脱浊处理.通过混凝烧杯实验.考察了AS/PDM复配比例、PDM特征黏度对脱浊效果的影响.结果表明,对浊度28～30 NTU、温度5～9℃、藻含量7.57×103mL-1的太湖水,要达到2 NTU的余浊标准.仅用AS需投加质量浓度4.29 mg/L,而采用m(AS):m(PDM)分别为5:1、10:1、20:1的复合混凝剂所需投加质量浓度随PDM特征黏度(0.55～2.47 dL/g)的增加分别为2.40～2.29、2.98～2.84、3.49～3.17 mg/L,相对于AS投加量减少44.06%～46.62%、30.54%～33.80%、18.65%～26.11%.PDM提高AS的混凝脱浊效果,并且AS/PDM复合配比越低,PDM特征黏度越高,则该复合混凝剂的脱浊效果越好.     

PAC、PFS混凝剂去除微污染水体中PCBs效果研究

以聚合氯化铝(PAC)、聚合硫酸铁(PFS)为混凝剂,采用强化混凝的水处理方法,完成对低浊度微污染水体中多氯联苯(PCBs)的去除,考察了2种混凝剂的投加量、水样初始浊度、水样pH值以及水力条件等因素对PAC、 PFS混凝剂去除低浊度水体中PCBs的效果影响。研究得出,当PAC投加量为7 mL/L,水样初始浊度为62NTU,慢速搅拌时间为15 min, pH值为5.0时, PAC强化混凝效果最佳,其对水样中PCBs的去除率为68.42%～76.02%,剩余浊度为1.01 NTU;当PFS投加量为5.5 mL/L,水样初始浊度为62 NTU,慢速搅拌时间为15 min,p H值为6.5时, PFS强化混凝效果最佳,其对水样中PCBs的去除率为70.30%～77.52%,剩余浊度为4.14 NTU。研究得出, PAC、 PFS均能有效去除微污染水体中的PCBs,且与PAC相比, PFS的去除效果更佳。     

复合聚铝用于冬季太湖水的混凝脱浊研究

将特征黏度系列化的聚二甲基二烯丙基氯化铵(PDM)与聚合氯化铝(PAC)复合用于冬季低温太湖原水强化混凝脱浊处理。由混凝烧杯实验,考察了PAC/PDM复合比例、PDM特征黏度对脱浊效果及絮团沉淀性能的影响,并与经预加氯处理的太湖水的相应处理结果作对比。结果表明,对浊度在24~26 NTU,温度为5~9℃,藻含量为8.01×103个/mL的太湖水,在与某市某水厂混凝强度相近的搅拌强度下,要达到其2 NTU沉淀池出水的余浊标准,PAC投加量3.28 mg/L,而复合比例分别为20∶1、10∶1、5∶1的PAC/PDM复合混凝剂所需PAC投加量随PDM特征黏度0.55、1.53、2.47 dL/g的增加,分别为2.93~2.83,2.70~2.60,2.62~2.51 mg/L,相应的PAC投加量减少的幅度分别为10.67%~13.72%,17.68%~20.73%,20.12%~23.48%;当沉淀出水浊度要求提高至1 NTU时,PAC需4 mg/L的投加量,复合混凝剂需3.77~3.04 mg/L的投加量,相对于PAC可减少投加量5.75%~24.00%。可见PDM明显提高了PAC的混凝脱浊效果,且PAC/PDM复合配比越低,PDM特征黏度越高,复合混凝剂的脱浊效果与沉淀性能越好。此外,PAC/PDM复合混凝剂有可能通过减少预加氯的投加量,来减少卤代有机物的形成机会,增强供水水质安全性。     

无机盐对PAC/PDM黏度行为和混凝性能的影响

该文考察了无机盐对聚合氯化铝(PAC)/聚二甲基二烯丙基氯化铵(PDM)复合混凝剂黏度行为和混凝性的影响,进一步考察了两种影响的关联性。用乌氏黏度计测定了无机盐对PAC/PDM比浓黏度的影响,同时采用混凝烧杯考察了无机盐对PAC/PDM混凝脱浊效果的影响。结果表明,不同无机盐对复合混凝剂黏度行为有不同影响,影响强度顺序依次为AlCl3>MgCl2>NaCl,Na2SO4和Na3PO4使复合混凝剂产生白色沉淀;由混凝实验可知:对于复合混凝剂的混凝脱浊效果,AlCl3能使其明显提高,MgCl2和NaCl对其无明显影响,Na2SO4使其效果明显变差,Na3PO4使其效果先变差后变好。由此可见,在实验范围内,无机盐对复合混凝剂黏度行为的影响与其对复合混凝剂混凝性能的影响无显著关联性。     

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。