粉煤灰改性方法及机理的研究进展

我国粉煤灰排放量大，严重污染环境。鉴于粉煤灰的化学吸附和物理吸附双重特性，利用粉煤灰处理氨氮废水可以达到以废治废目的。目前粉煤灰对氨氮废水的吸附量较低，因此通过粉煤灰改性提高对氨氮废水的吸附量具有重要意义。本文概述了粉煤灰的应用现状及改性粉煤灰对氨氮废水吸附性能研究进展，粉煤灰改性可以破坏粉煤灰网状结构，断裂其Si-O、Al-O键，激发活性组分Al₂O₃和SiO₂,提高粉煤灰的比表面积和孔道数量，利于对氨氮废水吸附。     

改性粉煤灰处理印染废水的研究

主要对改性粉煤灰处理印染废水进行了研究。通过实验考察了吸附时间、吸附温度、改性粉煤灰加入、改性粉煤灰粒度和废水的pH对废水中色度去除率的影响。实验结果表明,改性粉煤灰处理印染废水的其最佳工艺条件为:吸附时间为70min、吸附温度为30℃、改性粉煤灰加入量为2.4g、改性粉煤灰粒度为100～120目、废水pH为10.0。在此条件下可使100 mL模拟印染废水中色度由600倍降到65倍,色度去除率达89.2%,达到了国家《污水综合排放标准》二级标准。     

改性粉煤灰处理含苯胺废水的研究

文章对十六烷基三甲基溴化铵(CTAB)改性粉煤灰处理含苯胺废水进行了研究。通过实验考察了吸附时间、改性粉煤灰粒度、吸附温度、废水的pH和改性粉煤灰加入量对废水中苯胺去除率的影响。实验结果表明,改性粉煤灰处理含苯胺废水的最佳处理条件为:吸附时间为30 min、改性粉煤灰粒度为120~140目、吸附温度为25℃、废水的pH为3.0、改性粉煤灰加入量为6 g。在此条件下可使50 mL模拟含苯胺废水中苯胺的浓度由500 mg/mL降至15.03 mg/mL,苯胺的去除率达97%。利用改性粉煤灰处理含苯胺废水不仅处理效果好而且达到了以废治废的目的。     

改性粉煤灰吸附低浓度含砷含氨氮废水的机理研究

在有色金属冶炼、矿山采矿等行业里,排放废水中的砷和氨氮均存在不同程度的超标。本实验采用改性粉煤灰对低浓度砷和氨氮废水进行吸附处理。考察了溶液p H值、反应时间对改性粉煤灰除砷和氨氮的处理效果。实验结果表明:改性粉煤灰对两种污染物都有较好的去除效果。改性粉煤灰对氨氮的吸附符合Langmuir吸附等温线模型,对砷的吸附符合Freundlich吸附等温线模型;且均符合准二级动力学。其吸附去除机理是由于三价铁离子与砷发生反应形成难溶的化合物;氨氮的去除主要是由于改性粉煤灰表面的离子交换作用。     

改性粉煤灰处理含油废水的实验研究

采用不同的方法对粉煤灰进行了改性,并用得到的各种改性粉煤灰对含油废水进行了处理。结果表明:在几种改性粉煤灰中,经AlCl3和FeCl3改性处理的粉煤灰除油效果最好。同时探索了改性粉煤灰吸附处理含油废水的最佳工艺条件并得到其等温吸附方程及曲线。实验表明改性粉煤灰除油的最佳工艺条件为:室温,pH=10,搅拌时间为30min,灰水的质量比为1∶10。在该工艺条件下,含油废水经粉煤灰吸附处理后,出水含油量由256mg·L-1降至9·3mg·L-1,除油率为96·36%,达到国家含油废水一级排放标准。     

酸改性粉煤灰对罗丹明B的吸附研究

采用盐酸改性粉煤灰为吸附材料,以罗丹明B的模拟废水为吸附对象,研究了改性粉煤灰的投入量、吸附时间、温度及溶液pH值对吸附效果的影响。研究表明,对50 mL浓度2 mg/L的罗丹明B模拟废水,酸改性粉煤灰的最佳吸附条件是：在50℃下,加入0.09 g的粉煤灰,调节pH值为1.77,搅拌30 min。改性粉煤灰对罗丹明B吸附的脱色率可达98.19%。     

改性粉煤灰的制备及性能研究

在高钙粉煤灰中加入强碱液制备了改性粉煤灰,测定结果表明,改性后粉煤灰的堆积密度、比表面积、颗粒形貌等明显优于改性前。改性后粉煤灰的孔隙发达,吸附性能显著提高,对废水中Pb~(2 )的去除率达99.99%。同时对金属阳离子具有很强的吸附能力,可在吸附酸性气体及处理酸性废水等方面进一步探索。     

改性粉煤灰对水中硫化物吸附性能研究

用粉煤灰经氢氧化钠改性后吸附水中硫化物,研究了改性后的粉煤灰在不同温度、粒度、用量、时间下对硫化物的吸附差异性,同时用改性后粉煤灰在最佳的吸附条件下处理了生活废水,吸附效果较好。     

改性粉煤灰处理含铬（Ⅵ）废水的研究

文章对改性粉煤灰处理含铬（VI）废水进行了研究。通过实验考察了改性粉煤灰加入量、吸附时间、吸附温度和废水的pH对废水中铬（VI）去除率的影响。实验结果表明,改性粉煤灰处理含铬（Ⅵ）废水的最佳工艺条件为：改性粉煤灰加入量为1．5g,吸附时间为10min,吸附温度为25℃,废水的pH为6．0。在此条件下可使50mL模拟含铬废水中铬（VI）浓度由10mg／L降到0．47mg／L,铬（VI）去除率达95％以上,达到了国家《污水综合排放标准》。     

改性粉煤灰对有机废水的吸附试验研究

本文分别用改性前和改性后的粉煤灰对模拟印染废水进行吸附研究,通过试验得到较优化的工艺条件,结果表明,粉煤灰经酸改性后,其吸附效果大大提高。     

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。