改性木质素基水凝胶的制备及其对Cr（Ⅵ）和甲基橙的吸附研究

以木质素磺酸钠(LS-Na)为基础,通过接枝共聚反应引入阳离子单体丙烯酰氧乙基三甲基氯化铵(DAC),制备了改性木质素基水凝胶(MLH),利用傅立叶变换红外光谱仪(FTIR)和扫描电镜(SEM)对其结构进行了表征,并研究了其对模拟混合废水中Cr(Ⅵ)和甲基橙的竞争吸附作用及影响因素,同时开展了吸附动力学和等温吸附模型研究。结果表明,在pH值为5、MLH投加量为0.10 g、初始浓度为200 mg·L^-1、温度为30℃的条件下,Cr(Ⅵ)和甲基橙的吸附量分别为54.14 mg·g^-1和42.91 mg·g^-1;MLH对Cr(Ⅵ)和甲基橙的吸附过程符合准二级动力学方程和Freundlich等温吸附模型,Cr(Ⅵ)和甲基橙在MLH表面存在竞争吸附,且Cr(Ⅵ)更具被吸附优势;模拟混合废水中无机盐离子的存在会抑制MLH对Cr(Ⅵ)和甲基橙的吸附;MLH具有较好的重复再生性能。     

改性活性炭对甲基橙的吸附

用盐酸和氨水对活性炭进行改性获得改性活性炭,将其用于处理甲基橙废水,考察了改性条件、振荡速度和温度等因素对甲基橙吸附性能的影响,采用吸附等温模型和吸附动力学模型进行拟合,并分析吸附过程的热力学特征. 结果表明,盐酸改性活性炭对甲基橙的吸附效果优于氨水改性活性炭,在甲基橙初始浓度60 mg/L、溶液体积50 mL、温度20℃、振荡速度100 r/min、盐酸改性活性炭投加量0.2 g时,24 h基本达到吸附平衡,甲基橙去除率为93.7%. 不同温度下,盐酸改性活性炭对甲基橙的吸附符合Langmuir(RC2>0.95)和Freundlich(RC2>0.97)吸附等温模型,饱和吸附量达112.7 mg/g. 热力学参数DG0<0,DH0>0,DS0>0,表明盐酸改性活性炭对甲基橙的吸附是自发吸热反应,其吸附动力学可用准二级动力学方程描述,随振荡速度增加,吸附速率常数增加.     

HNO_3改性鱼鳞对染料废水中甲基橙吸附探究

利用HNO_3对草鱼鱼鳞浸泡改性制备吸附剂,通过系列吸附实验,考察甲基橙初始浓度、鱼鳞投加量和吸附温度等因素对改性鱼鳞吸附水中的甲基橙性能的影响,通过FTIR、XRD、吸附等温线和吸附动力学分析吸附机理。结果表明,鱼鳞用1 mol/L HNO_3浸泡3 h所制备的吸附剂对甲基橙染料废水具有很好的吸附性能;在室温(20～25℃)条件下,溶液pH介于4～9,10 g/L改性鱼鳞吸附剂的投加量和初始甲基橙浓度为100 mg/L时,改性鱼鳞吸附剂对甲基橙吸附在反应2 h时效果最佳;通过吸附等温线实验发现,HNO_3改性鱼鳞对甲基橙的吸附符合Freundlich吸附等温式,而动力学实验表明吸附过程符合准二级动力学模型;FTIR和XRD分析表明,HNO_3改性鱼鳞溶解了其中部分羟基磷灰石,对甲基橙的吸附主要是改变其物理结构而提高吸附效果。     

复合改性蒙脱石的制备及对甲基橙吸附性能的研究

本实验分别用CTAB(十六烷基三甲基溴化铵)和三氯化铁对蒙脱石进行有机改性和无机改性,并探究了其对甲基橙吸附能力的研究。通过实验得出复合改性后的蒙脱石对甲基橙的最佳吸附条件为:吸附时间为75 min,甲基橙的浓度为32 mg/L,复合改性蒙脱石与32 mg/L的甲基橙溶液的最佳固液比为6. 4∶1,在最佳吸附条件下有机-无机复合改性后的蒙脱石对甲基橙的吸附率可达到97. 96%,未改性的蒙脱石吸附率只有57. 41%,复合改性后的蒙脱石对甲基橙的吸附率有显著的提高。     

硫酸改性甘草废渣对结晶紫和甲基橙染料的吸附

将改性甘草废渣生物吸附剂(SGR)用于对含结晶紫和甲基橙染料模拟废水的吸附。通过扫描电镜、红外光谱和表面官能团的测定对改性前后的甘草废渣进行了表征。结果表明:经硫酸改性后,甘草废渣表面结构发生了变化,表面活性基团的数目也相应增加。根据Langmuir等温方程式计算SGR对结晶紫和甲基橙的饱和吸附量分别为157.60、64.86 mg/g。改性甘草废渣吸附剂对两种染料的吸附符合二级动力学方程。     

CTMAB-13X分子筛的制备及对水中甲基橙的吸附

用十六烷基三甲基溴化铵(CTMAB)对13X分子筛进行改性制备CTMAB-13X分子筛,研究了不同条件下CTMAB-13X分子筛对废水中甲基橙的吸附性能、影响因素及动力学过程.结果表明:CTMAB-13X分子筛投加量为0.1 g/L,吸附时间10 min后对甲基橙吸附可达平衡,此时去除率达到88.9％.CTMAB-13X分子筛吸附容量为275mg/g,高于活性炭的182 mg/g.Zeta电位分析说明经阳离子表面活性剂CTMAB改性的13X分子筛表面带正电,对水中带负电的酸性染料甲基橙有较强的吸附效果.由红外吸收光谱(FTIR)看出CTMAB的特征峰出现在CTMAB-13X分子筛中,说明CTMAB接枝改性到13X分子筛表面.分析X-射线图谱得出CTMAB改性剂没有破坏13X分子筛自身的晶体结构,进一步证明CTMAB是接枝在分子筛表面.从扫描电镜(SEM)可以看出改性后的CTMAB-13X分子筛更为分散,因此可以为染料分子提供更多的吸附点位.激光粒度测定结果表明CTMAB-13X分子筛平均粒径Dav由17.45 μm下降到12.41 μm,比表面积(S/V)由5143.69 cm2/cm3增大到7752.48 cm2/cm3,与SEM分析结果一致.     

热改性高硅煤矸石对甲基橙的吸附性能研究

用煅烧的方法对高硅煤矸石进行热改性，制备出热改性煤矸石。采用吸附热力学模型拟合热改性煤矸石对甲基橙的吸附特性，并结合XRD和SEM分析表征手段探讨了其吸附机制。结果表明：热改性煤矸石结构变得疏松，孔隙率增加。在650℃煅烧2 h得到的热改性煤矸石对甲基橙的吸附量和去除率最大，其最佳吸附条件为：吸附温度为25℃(常温)，吸附时间为1 h，热改性煤矸石加入量为6 g·L^-1，甲基橙初始质量浓度为50 mg·L^-1。热改性煤矸石对甲基橙溶液的吸附符合Langmuir模型和Freundlich模型，但更适合用Langmuir模型进行表述，属于单分子层吸附。热改性煤矸石对甲基橙的吸附体系稳定性较差，但吸附过程易于进行。     

热改性膨润土对甲基橙废水的吸附

研究了热改性膨润土对甲基橙的吸附性能。结果表明改性的方法能够明显地改善膨润土在水中的沉降性与过滤性,大大地提高了膨润土对甲基橙的吸附能力。在pH等于7及常温条件下,当经300℃煅烧2h的热改性膨润土的用量为12g／L时,对浓度为248mg／L的甲基橙的吸附量和去除率分别为22．12mg／g、98．58％;对浓度为41．0mg／L的甲基橙的去除率达97．4％。     

石墨烯气凝胶的制备及其对六价铬和甲基橙的共吸附性能

利用氧化石墨烯和没食子酸,采用水热合成法制备了石墨烯气凝胶。通过扫描电镜(SEM)、X射线衍射分析(XRD)和傅里叶变换红外光谱(FTIR)对石墨烯气凝胶进行了表征,并简要分析了石墨烯气凝胶对水溶液中六价铬和甲基橙的同步吸附性能。实验结果表明,石墨烯气凝胶表面疏松多孔,表面官能团丰富。在实验条件下,振荡时间为350 min时,六价铬和甲基橙的吸附量同时达到最大值,分别为39.21 mg/g和125.35 mg/g。六价铬与甲基橙在石墨烯气凝胶表面存在竞争吸附。石墨烯气凝胶具有同步去除水溶液中六价铬和甲基橙的优异性能。     

次氯酸钠改性磁性碳纳米管吸附剂的制备及吸附性能研究

本文利用直接制备的碳纳米管原始样品作为偶氮染料的吸附剂,采用次氯酸钠溶液对碳纳米管进行表面修饰改性,改性后显著提高了吸附剂的吸附容量,本工艺简单有效,所获得的吸附剂具有磁性,吸附过后用磁铁易于达到固液分离的效果.吸附性能结果表明,次氯酸钠改性后碳纳米管对水中甲基橙去除效果明显高于未改性的碳纳米管.吸附剂对水中甲基橙的吸附在70 min基本达到平衡,吸附过程符合准2级动力学模型(R2＞0.99).改性后的磁性碳纳米管吸附甲基橙的平衡吸附量qe与甲基橙溶液的平衡浓度ρe的关系满足Langmuir(R2＞0.99),Freundlich ( R2＞0.98)以及Dubinin-Radushkevich(D-R)(R2＞0.99)等温吸附模型.通过Langmuir模型计算可知改性磁性碳纳米管最大吸附容量为29.2 mg·g-1,吸附过程为有利吸附,由D-R模型计算结果可以推断,次氯酸钠改性后的磁性碳纳米管对水溶液中甲基橙的吸附以物理吸附为主.     

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。