水泥固化铬污染土强度及浸出试验研究

为了解决重金属铬污染带来的土壤及地下水污染问题,以沈阳铬渣堆场污染土为研究对象,进行水泥固化重金属铬污染土中Cr(VI)和Cr(Ⅲ)试验研究,测定了水泥掺量、养护龄期、铬不同含量及价态对固化土体的无侧限抗压强度及淋滤特性影响.结果表明,水泥是Cr(VI)和Cr(Ⅲ)污染土的有效固化剂,水泥掺量以20%为宜;Cr(VI)和Cr(Ⅲ)对固化土强度都具有弱化效应,Cr(Ⅲ)弱化效应更明显;SEM图从微观上解释了水泥固化铬污染土强度的变化,该变化与无侧限抗压强度试验结果一致.     

钢渣微粉用于重金属污染土壤固化剂实验研究

采用正交试验法研究了钢渣微粉固化剂对重金属污染土壤的修复效果.原土经过固化处理后,Cr、Ni、Cu、Zn和Pb的浸出浓度大大降低,浸出浓度普遍下降了99％以上,但掺量、时间、固液比、钢渣微粉比例对重金属的浸出浓度呈现了不同的影响,浸出浓度结果证明了钢渣粉除了具有胶凝性的特征外,其多空性和富含碳酸盐、铁锰氧化物等特点能够使其具有更加优越的固化效果.同时,经过处理后的固化体无侧限抗压强度可达2.4 MPa以上,且与时间、掺量具有良好的相关性,但钢渣微粉比例的增加能够一定程度降低固化体的前期强度.     

固化/稳定化技术应用于重金属污染土壤修复的研究进展

有害重金属对土壤的污染是全球亟待解决的环境问题。固化/稳定化作为一种相对成熟、经济、有效的土壤修复技术,是目前我国土壤重金属修复的最主要技术。固化/稳定化修复技术通过向土壤中添加固化/稳定化剂,从而将污染物封存或改变其形态,达到减少其迁移性、生物有效性及浸出毒性的目的。本文介绍了固化/稳定化技术修复重金属污染土壤,总结常用的固化/稳定化剂种类及其对重金属污染土壤的修复机理和影响因素,并归纳了几种用于固化/稳定化修复效果评价的方法,最后针对固化/稳定化修复过程中存在的问题,提出今后发展的方向。     

固化稳定化技术修复化工厂污染土壤中的实验研究

目的:探究固化稳定化技术对化工厂污染土壤修复时的固化效果和稳定化效果。方法：选择以某地区金属冶炼化工厂为依托，获取化工厂场地中污染土壤作为实验样本，在改变固化稳定化技术中稳定剂、固化剂添加量的条件下，对土壤本身pH值变化和污染物浸出质量浓度变化进行分析。结果：稳定剂添加量越大，土壤pH值越高，土壤中污染物浸出质量浓度逐渐降低，在15%前变化幅度较大，随后逐渐减缓；固化剂添加比例增加，土壤中污染物浸出质量浓度逐渐降低；添加的固化剂会发生水化反应，提高了土壤对污染物的吸附能力。结论：在应用固化稳定化技术对污染土壤进行修复时，应将稳定剂配比控制在5%～15%，将固化剂配比控制在15%～25%，以此能够达到最佳的土壤修复效果。     

石灰和粉煤灰固化修复六价铬污染土试验研究

为解决受污染土壤中六价铬浸出和渗透到地下水带来的环境污染问题,以沈阳铬渣堆场污染土壤为研究对象,进行石灰和粉煤灰联合修复铬污染土试验研究,分析石灰和粉煤灰不同剂量、养护龄期对污染土六价铬浸出的影响,分析了两者联合修复机理.研究结果表明:在固化修复0.4％ Cr(VI)污染土中,组合添加10％～15％生石灰和25％～35％粉煤灰养护28 d有较好效果,浸出液铬离子浓度均在规定界限5 mg·L-1以下;主要修复机理为较高的基质pH值促进了Cr(VI)与粉煤灰表面的物理-化学相互作用,以及生石灰与粉煤灰的火山灰反应.     

某退役磷化工场地重金属及氟化物复合污染土壤异位固化/稳定化修复试验研究

针对某退役磷化工场地重金属及氟化物复合污染土壤,开展异位固化/稳定化修复效果试验研究。对测试土壤样品分别采用固化/稳定化药剂A-Ⅰ、A-Ⅱ、A-Ⅲ、A-Ⅳ、A-Ⅴ投加不同比例(3%、5%、7%)进行多组试验,对修复前后土壤进行浸出毒性分析,以评价固化/稳定化药剂类型、药剂投加比等特性与污染土壤修复效果之间的差异。结果表明：A-Ⅰ、A-Ⅱ系列药剂对重金属及氟化物复合污染土壤有较好的固化/稳定化效果,A-Ⅲ对重金属污染土壤固化效果显著。     

冶金污泥用于路基回填土的试验研究

以冶金污泥资源化为宗旨,对冶金污泥固化/稳定化后用于路基回填土进行研究。试验研究表明,通过适宜固化处理工艺,冶金污泥能够满足路基回填土物理化学、力学以及重金属浸出安全性等要求。选用水泥、石灰和粉煤灰作固化剂（内掺）,适宜掺量为20%（水泥5%、粉煤灰10%、石灰5%）和掺量为25%（15%水泥、10%粉煤灰）,对于公路等级较低的公路,还可以进一步减少固化剂掺量,以降低成本。     

生活垃圾焚烧炉渣与矿渣双掺制备少熟料砌筑水泥的研究

对生活垃圾焚烧炉渣与矿渣双掺制备的少熟料砌筑水泥的各项物理性能及其制品中重金属溶出的环境安全性进行了研究。结果表明：炉渣掺量越高,砌筑水泥胶砂强度越低;复掺矿渣后,炉渣中的碱离子能激发矿渣的活性,使强度降幅减小;掺入占矿渣掺量9％的水玻璃（固含量为45％,模数为1．6）能有效改善凝结时间,使之达到标准要求;当炉渣掺量为45％,矿渣掺量为44％,水泥掺量为11％时,能在最大限度消耗炉渣、使用矿渣和减少熟料的同时,保证强度达到最佳值;掺炉渣和矿渣的砌筑水泥制品的重金属浸出浓度均低于浸出毒性标准限值,且低于V类地表水标准限值,不会对环境造成污染。     

重金属镍、镉、铜污染土壤固化/稳定修复

以江苏常州市某化工厂拆迁后遗留场地中含有重金属污染的土壤为研究对象,通过正交试验向土壤中添加有机和无机复合药剂,以固化/稳定后土壤中重金属的浸出浓度为评价指标,确定最优的固化/稳定化药剂配比。试验结果表明:经过固化/稳定化后的土壤中重金属Ni、Cd、Cu的浸出浓度大幅降低,固化/稳定化率高于90%,接近95%,重金属浸出浓度远远低于GB5085.3-2007标准中各重金属的浸出浓度限值。     

化学稳定化修复技术在重金属污染土壤修复中的应用研究

本研究以福建省尤溪县某农田污染地块为例,采样化学稳定化修复技术对农田污染地块土壤进行修复,研究结果表明采用“碱性材料+生物炭”复合固化剂适用于福建省铅锌矿区受污染农田修复,修复10d后重金属Pb有效量固化率为46.34%～80.89%,重金属Cd有效量固化率为53.83%～68.92%,修复后土壤中的重金属Pb和Cd有效量含量低于《农产品产地土壤重金属污染程度的分级》（DB35/T859-2016）中限制值,修复后的农田可进行农业生产。     

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。