三巯三嗪三钠处理矿山废水中多种重金属离子的实验研究

采用重金属捕集剂三巯三嗪三钠(TMT)深度处理低含量矿山废水中Cu2+、Zn2+、Pb2+、Cd2+、Cr3+等多种混合重金属离子,研究了pH、添加量、搅拌时间、反应时间、温度以及絮凝剂等因素对处理效果的影响。结果表明,调节废水pH为7左右,投加0.4 mL质量分数为10%的TMT溶液,室温下搅拌5 min再添加适量联合絮凝剂,总反应20 min后,各重金属离子去除率均达到98%以上,出水中所考察的重金属离子含量均远低于GB 8978-1996排放要求,捕集产物稳定性高,二次污染风险小。因此,TMT在深度处理低浓度多金属离子共存的矿山废水领域具有较好的应用前景。     

硫化钠-重金属捕集剂组合处理酸性含镍废水

采用硫化钠-重金属捕集剂组合处理酸性含镍废水,研究了药剂的加入量、反应时间、pH值和加药方式对废水中Ni 2+的去除率的影响。结果表明:在反应时间超过30min,硫化钠和重金属捕集剂按理论量投加,pH值大于4,先投加组合药剂再用NaOH调节pH值的条件下,出水中Ni2+的质量浓度达到国家排放标准,渣中镍的质量分数大于14%,具有回收价值,且处理过程中无H2S气体溢出,可以实现工业酸性含镍废水的资源化、无害化处理。     

重金属捕集剂对废水中铅捕集效果研究

研究了几种重金属捕集剂对含铅废水的处理效果，讨论了反应时间、捕集剂加入量、pH值及多种重金属离子共存条件下各种捕集剂对铅处理效果的影响。实验结果表明，在反应时间为20min，捕集剂加入量为理论用量的1．2倍，pH值为2～6时处理效果较好，捕集效率在99％以上，且多种重金属离子共存条件下对捕集效果没有影响，处理后的废水能达到重金属国家排放标准。因此采用该方法优于传统处理方法，有很好的应用前景。     

重金属捕集剂在电镀重金属废水中的应用研究

针对传统化学沉淀方法处理实际电镀综合废水中重金属离子无法达标的问题,选取了3种市售重金属捕集剂对实际电镀废水中的Cu2+、Zn2+、Ni2+进行同步深度处理,采用红外光谱分析仪对3种捕集剂的分子结构进行表征,并比较了三者对电镀废水中重金属离子的处理效果。结果发现,三聚硫氰酸三钠(Trimercaptotriazine,简称TMT)对Cu2+的去除效果最为显著,投加量少且效果稳定,但对Ni2+的去除效果较差。在二硫代氨基甲酸盐类(Dithiocarbamate,简称DTC)捕集剂中,Me2DTC(Me=—CH3)的适用性最强,对3种重金属离子均具有良好的去除效果,可达到《电镀废水排放标准》(GB 21900—2008)中表3的排放标准,且在p H=9.70时,处理效果最佳;Et2DTC(Et=—CH2CH3)对Ni2+的去除效果不佳,表明DTC分子结构中的取代基种类不同,可能会对Ni2+的捕集效果产生较大影响。     

重金属捕集剂强化混凝处理制革废水的研究

以某皮革企业排放的综合废水为研究对象,选取重金属捕集剂作为除铬沉淀剂,探讨捕集剂种类、添加量、体系pH、温度、絮凝剂与助凝剂添加量、沉降时间对除铬效果的影响。结果表明,LX-Y803的除铬效果最好,最佳投药量为90 mg/L,最佳pH为9,温度为50℃。添加絮凝剂和助凝剂强化沉降,结果表明,PAM最佳投加量为2.5 mg/L,助凝剂最佳投加量为0.2 mg/L,最佳沉降时间为15 min。最终,总铬去除率可达98.27%,有机铬去除率为97.08%,无机铬去除率为99.62%,处理后废水中的总铬为0.97 mg/L,达到GB 30486—2013《制革及毛皮加工工业水污染物排放标准》要求。     

重金属捕集剂强化混凝处理含锌电镀废水的试验研究

文章以梅州电声元件行业配套电镀企业某电子发展有限公司的含锌电镀废水为研究对象,选取4种药剂作为锌捕集剂,设计试验探讨捕集剂种类、投加量、反应体系pH、絮凝剂联用等操作因素对其处理效果的影响。结果表明,影响锌去除率的因素主次顺序是pH捕集剂种类投加量,可见pH的影响最大;而除锌效果最好的捕集剂为铜试剂,最佳投药量为6 mg/L,最佳pH为8;再通过最佳捕集剂与絮凝剂联用试验,筛选出除锌效果最好的强化混凝条件为:pH为8,铜试剂投药量为6 mg/L,PAC投药量为14 mg/L,PAM投药量为1.6 mg/L。最后,将该结果用电镀废水进行验证,锌的去除率达到99.01%,其处理后水中锌的浓度为0.46 mg/L1.00 mg/L,达到《电镀污染物排放标准》(GB21900-2008)。     

螯合沉淀法处理含铬电镀废水

以NaHSO3为还原剂,新型重金属离子捕集剂DTCR为螯合剂,采用螯合沉淀法处理含铬电镀废水。研究了还原剂投加量、还原反应阶段的废水pH、螯合剂投加量、絮凝剂(PAM)投加量、螯合沉淀阶段的废水pH和搅拌时间对处理效果的影响。还原反应的较优工艺为:NaHSO3200mg/L,废水pH1.84,搅拌时间30min。螯合沉淀的最佳工艺条件为:DTCR70mg/L,PAM8mg/L,废水pH8.0,搅拌时间40min。采用最佳螯合沉淀工艺处理含铬电镀废水时,总铬去除率在95%以上,出水总铬为0.14mg/L,且未检测到其他重金属离子,可达标排放。     

超声波-铁氧体法处理含镍模拟电镀废水的研究

采用超声波-铁氧体法对含镍模拟电镀废水进行处理,考察了pH值、超声波辐射时间、声能密度、H2O2的投加量、加料摩尔比(nFe2+∶nNi2+)、Ni2+的初始质量浓度以及不同金属离子共存对废水中Ni2+的去除率的影响.结果表明:在H2O2的投加量为28.4 mg/L,加料摩尔比为2,pH值为11.5,温度为50℃,反应时间为45 min的条件下,废水中Ni2+的质量浓度从250 mg/L降至0.495 mg/L,去除率达到99.40％,达到国家排放标准.     

Fenton试剂法处理苯酚废水的研究

采用Fenton试剂法以苯酚水样为处理对象,通过试验研究分析各因素对体系处理苯酚废水效果的影响.试验研究结果表明,对于质量浓度为100 mg·L-1的苯酚废水,试验确定的最佳反应条件为:H2O2投加量为14 mmol·L-1,Fe2+投加量为1.2 mmol·L-1,初始pH值为3,反应时间为30 min.在此条件下苯酚最大去除率达到了99.6%.     

重金属捕集剂XMT处理电镀废水中Cu2+的试验研究

以XMT作为重金属离子捕集剂,进行了电镀废水Cu2+的捕集研究,探讨了XMT加入量、pH、絮凝剂加入量及反应时间等因素对Cu2+捕集效率的影响.结果表明,质量分数为10％的XMT加入量2.0mL、pH=3～12、质量分数为0.01％的PAM絮凝剂加入量1.0 mL、反应时间10～30 min等优化工艺条件下,Cu2+去...     

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。