铝污泥基复合凝胶球对Cr(Ⅵ)的吸附性能与机理

以铝污泥、聚乙烯醇、海藻酸钠为原料,采用溶胶-凝胶、冷冻干燥技术制备铝污泥基复合凝胶球(AS-GEL),用于吸附溶液中Cr(Ⅵ).通过静态吸附实验探究pH、AS-GEL投加量、初始质量浓度、温度、吸附时间、共存阴离子浓度对AS-GEL吸附Cr(Ⅵ)的影响.采用SEM、FTIR、XPS对AS-GEL吸附Cr(Ⅵ)的机理进行分析.结果表明,在pH=4、AS-GEL投加量为1.2 g/L、Cr(Ⅵ)初始质量浓度200 mg/L、温度为35℃、吸附时间为120 min、无其他阴离子共存的条件下,AS-GEL对Cr(Ⅵ)的最大吸附量为73.364 mg/g.共存阴离子影响顺序为PO43–>NO3–>Cl–.吸附过程符合Langmuir等温吸附模型和准一级、准二级动力学方程.其主要吸附机理包括质子化基团对Cr(Ⅵ)的静电吸附及还原作用.5次吸附-解吸实验后,其吸附量保持初次吸附量的89.71％.同时,AS-GEL具有成本低、固液易分离的特性,有望应用在工程上.     

改性核桃壳去除Cr(VI)的实验研究

采用磷酸对核桃壳进行改性,以提高核桃壳对Cr (VI)的吸附效果。实验考察了吸附时间、含Cr(VI)水样的初始浓度、吸附剂投加量以及pH等因素对改性核桃壳吸附Cr (VI)效果的影响。实验结果表明:含Cr(VI)水样初始浓度为20 mg/L,体积为50 m L时,吸附剂投加量为0. 7 g,吸附时间为2 h,吸附效果最佳,此时去除率为90. 36%,优于未改性核桃壳。其吸附过程符合拟二级动力学方程及Langmui等温方程。     

热改性铝污泥对水中磷的吸附性能

考察了接触时间、pH、投加量对热改性铝污泥吸附磷的影响,确定了其最佳吸附条件和影响因素顺序。结果表明,除磷影响因素依次为磷溶液初始浓度接触时间溶液pH投加量,改性铝污泥吸附除磷的最佳条件:初始磷浓度为60.00 mg/L,pH值为3.0,投加量为4 g/L,振荡反应时间为4 h,改性铝污泥对磷的最高去除率达77.2%。     

废白土榴莲壳粘土生物炭的制备及对Cr(VI)的吸附

以废白土与榴莲壳为原料制备了粘土生物炭吸附剂(spent bleaching earth biochar,SBEC)、以废白土为原料制备了粘土炭基吸附剂(spent bleaching earth,SBE)吸附废水中的Cr（VI）。用比表面积分析、SEM、XRD、FTIR对吸附剂进行了表征。考察了溶液初始pH、Cr(VI)溶液浓度、吸附剂投加量、吸附时间和吸附温度分别对吸附Cr(VI)的影响。25℃下pH为3时、SBEC 投加量为0.5g/L、Cr(VI)初始浓度为100mg/L、吸附时间120min,SBEC对Cr(VI)去除效率最高为86.1%,SBE则在pH为2去除效率最高为52.5%。SBEC、SBE对Cr(VI)的吸附过程符合准二级动力学模型，SBEC吸附过程符合Freundlich模型，SBE则与Langmuir吸附等温线模型较符合；吸附行为是自发吸热过程。经过5次吸附-脱附后,SBEC对Cr(VI)的去除率达58.8%。     

铝污泥对废水中铀(Ⅵ)的吸附机理研究

为处理放射性含铀废水,以铝污泥作为吸附剂进行吸附。采用静态吸附法,通过改变pH、投加量、铀溶液初始浓度、反应时间、共存离子等因素,分析其对吸附的影响,并使用等温吸附模型和动力学方程拟合实验数据。结果表明,铝污泥对铀的吸附适合弱酸性含铀废水,当铀的初始浓度为20 mg/L、pH=4、投加量为0.8 g/L、反应时间100 min时,吸附效果最好。通过等温吸附模型和动力学方程对数据的拟合,推出铝污泥对铀的吸附为化学多层吸附。通过扫描电镜(SEM)、X射线能谱分析(EDS)、傅里叶红外光谱(FTIR)对吸附前后的铝污泥进行表征,结果显示吸附反应主要有与官能团的络合反应及离子交换的化学反应。     

改性花生壳吸附去除水中Cr(Ⅵ)的性能研究

采用三乙烯四胺对花生壳颗粒进行改性制备吸附剂,以投加量、粒径、接触时间、Cr(Ⅵ)初始浓度、温度和溶液初始pH值为影响因素,通过静态实验,研究其对水中Cr(Ⅵ)的吸附性能。得到最佳吸附条件为吸附剂投加量1.0～1.6g/L,接触时间150min,初始浓度100mg/L,去除率可达99.36%,饱和吸附量达100.95mg/g。分析认为,主要的吸附机理可能是Cr2O27-与改性花生壳吸附点位上的功能基团之间的离子交换,伴随着静电吸附及氧化还原过程。     

废白土榴莲壳粘土生物炭的制备及对Cr(VI)的吸附

以废白土与榴莲壳为原料制备了粘土生物炭吸附剂(spent bleaching earth biochar,SBEC)、以废白土为原料制备了粘土炭基吸附剂(spent bleaching earth,SBE)吸附废水中的Cr（VI）。用比表面积分析、SEM、XRD、FTIR对吸附剂进行了表征。考察了溶液初始pH、Cr(VI)溶液浓度、吸附剂投加量、吸附时间和吸附温度分别对吸附Cr(VI)的影响。25℃下pH为3时、SBEC 投加量为0.5g/L、Cr(VI)初始浓度为100mg/L、吸附时间120min,SBEC对Cr(VI)去除效率最高为86.1%,SBE则在pH为2去除效率最高为52.5%。SBEC、SBE对Cr(VI)的吸附过程符合准二级动力学模型,SBEC吸附过程符合Freundlich模型,SBE则与Langmuir吸附等温线模型较符合;吸附行为是自发吸热过程。经过5次吸附-脱附后,SBEC对Cr(VI)的去除率达58.8%。     

铝污泥对废水中铀(Ⅵ)的吸附机理研究

为处理放射性含铀废水,以铝污泥作为吸附剂进行吸附。采用静态吸附法,通过改变pH、投加量、铀溶液初始浓度、反应时间、共存离子等因素,分析其对吸附的影响,并使用等温吸附模型和动力学方程拟合实验数据。结果表明,铝污泥对铀的吸附适合弱酸性含铀废水,当铀的初始浓度为20 mg/L、pH=4、投加量为0.8 g/L、反应时间100 min时,吸附效果最好。通过等温吸附模型和动力学方程对数据的拟合,推出铝污泥对铀的吸附为化学多层吸附。通过扫描电镜(SEM)、X射线能谱分析(EDS)、傅里叶红外光谱(FTIR)对吸附前后的铝污泥进行表征,结果显示吸附反应主要有与官能团的络合反应及离子交换的化学反应。     

水滑石焙烧产物对阴离子染料靛蓝胭脂红的吸附特性

碳酸根型水滑石焙烧产物对阴离子染料具有特异的吸附性能。该研究考察了两种具有不同镁铝摩尔比的镁铝复合氧化物对靛蓝胭脂红的吸附性能,并探讨了焙烧温度、投加量、初始染料浓度、溶液初始pH以及共存阴离子这几个因素的影响。结果表明经过500℃焙烧处理后的水滑石对染料的去除效果最好,去除率高达95%,平衡吸附量高达811.5 mg/g（1.74 mmol/g）;且吸附过程不受初始溶液pH和共存阴离子的影响。水滑石焙烧产物直接用于印染废水处理,脱色率达68%~84%。     

核桃壳生物质负载纳米零价铁对Cr(VI)污染土壤的修复研究

将核桃壳负载纳米零价铁制备核桃壳生物质负载纳米零价铁复合材料(WSP@nZVI),投加到Cr(VI)污染土壤中,通过土壤钝化实验,研究投加量、土水比和时间对Cr(VI)污染土壤的修复效果的影响,并探究可能的修复机理。分析处理前后土壤浸出液Cr(VI)浓度、土壤Cr(VI)含量、土壤总Cr含量以及土壤Cr形态含量的变化。结果表明,在投加量为7.5 mg/g,土水比为1∶10 g/mL,时间为2 d时,修复效果最佳。投加量越大,土水比越小,时间越长,修复效果越明显。其修复机制可能为吸附-还原-沉淀与共沉淀3种机理协同作用。     

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。