丙烯酸接枝改性丙纶非织造布的吸附与解吸研究

采用丙烯酸接枝改性聚丙烯非织造布(PP-g-AA)对阳离子红X-GRL染料进行吸附与解吸,探讨了PP-g-AA对染料的吸附动力学机理、解吸过程和解吸动力学机理,以及基于动态吸附的过滤分离操作,分析了PP-g-AA对染料吸附-解吸再生循环利用的可行性。结果表明:不同初始染料浓度下,PP-g-AA的吸附动力学符合Lagergren's准二级动力学模型和双指数模型;解吸液的最佳配比为表面活性剂质量分数5%,乙醇与水的体积比3∶7,解吸率随吸附量的增大呈现先增大后减小的趋势,解吸符合Lagergren's准二级动力学模型;动态吸附-解吸再生循环10次后,染料的去除率达96%以上,再生循环8次时,PP-g-AA的跨膜压力为37.1 k Pa,水通量最大达38.6 L/(m2·h)。     

2种超滤膜作为反渗透预处理工艺处理印染废水的比较

采用超滤和反渗透双膜技术处理广东省某印染污水处理有限公司的印染废水。分别使用了PVDF和PP中空纤维超滤膜,做为反渗透的预处理,并考察对比了2种超滤膜的性能和在相同操作条件下对印染废水的处理效果。结果表明,2种超滤膜均能有效地去除废水浊度和大分子有机物,PVDF膜对浊度的去除率达到了97%~99%,PP膜对浊度的去除率为94%~97%;2种超滤膜对SDI处理都能达到SDI<3,符合反渗透系统的进水要求。PVDF膜的膜通量稳定保持在18 L/(m2·h)以上,PP膜的膜通量在8~16 L/(m2·h)。PVDF膜的进水压力小于PP膜,能耗较低。PVDF膜的跨膜压差在0.08 MPa以下,PP膜的跨膜压差在0.13~0.19 MPa。PVDF中空纤维超滤膜对印染废水的处理性能要优于PP中空纤维超滤膜。     

改性火山岩颗粒吸附处理含Cu2+和Zn2+重金属废水影响因素研究

以改性火山岩颗粒作为吸附材料,处理含Cu2+和Zn2+重金属废水,探讨了pH、温度、改性火山岩投加量、吸附时间对吸附性能的影响。结果表明,当pH在3～6之间时,随着pH的增大,改性火山岩颗粒对Cu2+和Zn2+去除率显著提高,当pH大于6后,改性火山岩颗粒对Cu2+和Zn2+去除率增速变缓,并伴有沉淀出现;温度的影响表明:随温度升高改性火山岩颗粒对Cu2+和Zn2+去除效率升高,分析认为该过程是吸热反应,且为自发过程;对Cu2+吸附去除,改性火山岩颗粒最佳投加为10 g/L,对Zn2+吸附去除,改性火山岩最佳投加量为6 g/L;改性火山岩颗粒对Cu2+和Zn2+吸附去除过程属于快吸附过程,饱和吸附时间为8 h。     

光照溴化诱导接枝聚合两步法对PAN/PSU共混膜的表面改性

采用表面光接枝改性方法对聚丙烯情/聚砜(PAN/PSU)共混膜进行改性,对PAN/PSU共混膜进行光照溴化和紫外诱导接枝聚合丙烯酸,测定了膜的红外光谱、水通量和牛血清蛋白(BAS)截留率.结果表明:紫外光照溴化3 b后,PAN/PSU膜的结构即破坏,膜表面产生了C-Br键;随溴化程度增加,膜的水通量从67 L/(m2·h)下降到48 L/(m2·h),膜的BAS截留率从85%上升到92%;紫外诱导接枝聚合丙烯酸过程中,仅有少量溴参与改性.处理时间小于1 h,膜的分离特性未有明显改变;延长改性时间,膜的水通量降低,截留率升高.     

改性聚丙烯腈纤维处理电镀废水研究

将聚丙烯腈(PAN)纤维与羟胺试剂反应制备出改性PAN纤维。在20℃和动态条件下,对改性PAN纤维处理电镀废水进行了研究。结果表明,改性PAN纤维处理电镀废水效果很好:在20℃、废水体积流量3 mL/min、pH为4.0时,TOC和TN的去除率分别为70.6%和87.5%;对废水中Cu2+、Ni2+、Zn2+具有很好的吸附性能,其去除率分别为99.3%、98.9%、98.3%,吸附能力的大小为Cu2+>Ni2+>Zn2+。改性聚丙烯腈纤维再生利用率高,可重复利用。     

丙烯酰胺接枝聚丙烯多孔膜及其水解后的性能

采用丙烯酰胺接枝法对聚丙烯(PP)多孔膜表面进行亲水化改性,考察了硝酸浓度、接枝时间以及水解时间对膜结构和性能的影响。随硝酸浓度增加,接枝度先增后降,膜表面的水接触角先减小后增大;随接枝时间延长,接枝度先增加后几乎不变,水接触角先减小后趋于恒定;随水解时间延长,接枝度几乎不变,而水接触角先减小后趋于恒定。优选的亲水化改性条件下,PP多孔膜的接枝度为1 147μg/cm2,水接触角由124°降至47°。过膜压差为0.5MPa时,聚酰亚胺/PP纳滤复合膜的纯水通量和对1 g/L的Na2SO4溶液的截留率分别可达11.89 L/(m2·h)和92.86%。     

超滤法提纯异维生素C钠发酵液的研究

采用MF-5膜组件超滤2-酮基-D-葡萄糖酸发酵液,滤液质量高,收率可达98%以上;操作温度35～38℃,进口压力0.25MPa,出口压力0.15MPa,过滤中的平均膜通量为110L/(m2·h)。     

铜离子在印迹壳聚糖/Al2O3上的吸附-脱附特性

采用表面接枝和表面印迹技术,以正硅酸乙酯改性后的Al2O3粉末为载体、壳聚糖为功能单体,制备了Cu2+印迹复合材料(IIP/Al2O3),用于选择性分离Cu2+. 研究了IIP/Al2O3对Cu2+的动态吸附,利用Thomas, Yoon-Nelson和Wolborska模型分析IIP/Al2O3吸附Cu2+过程,考察了动态条件下Cu2+的最佳洗脱条件. 结果表明,当Cu2+浓度100 mg/L、柱高37.25 mm、流速1.0 mL/min和pH=5时,IIP/Al2O3的穿透吸附容量和动态吸附容量分别为4.03和15.68 mg/g,Cu2+去除率为45.55%;Thomas和Yoon-Nelson模型能很好地拟合IIP/Al2O3对Cu2+的吸附;在柱高37.25 mm、洗脱液流速1.0 mL/min的条件下,15 mL 0.6 mol/L盐酸溶液对Cu2+的脱附率高达99.54%,脱附作用时间短,Cu2+易回收.     

PTFE膜系统分离电镀漂洗水中Ni~(2+)、Cu~(2+)的实验研究

铜、镍为电镀废水中常见的金属离子,把其进行高效分离并回收,兼具环保与经济价值。本实验把PTFE中空纤维膜过滤系统嵌入到电镀工序的清洗线中,进行在线分离电镀漂洗水中常见的镍、铜离子。通过测定膜通量的变化及截留率效果,得到膜系统在室温下的主要运行条件:膜系统的最佳操作压力条件是0.7~0.8 MPa;膜系统的纯水通量为150 L/(m~2·h)时,Ni离子水样的平均截留率94.02%,Cu离子水样的平均截留率97.09%;Ni离子浓度最高为390.45 mg/L的水样,过滤时间t在55 min后,膜通量减少80%并趋向稳定;Cu离子浓度最高为392.64mg/L的水样,过滤55 min后膜通量减少77%并趋向稳定。研究表明,中空纤维膜系统对于电镀废水中的中重金属离子的分离具有良好的应用前景。     

浸没式纳滤印染废水深度处理研究

采用自制的中空纤维复合纳滤膜及浸没式过滤工艺,对含甲基蓝的印染废水进行深度处理,研究了不同跨膜压差、不同浓缩倍率下,浸没式纳滤工艺处理印染废水过程的渗透通量、脱色性能、COD去除率及膜渗透阻力。结果表明,浸没式纳滤可有效实现对印染废水的深度处理,在跨膜压差为80 kPa、浓缩倍率为4.0下,浸没式纳滤过程的渗透通量为5.75 L/(m2.h),色度脱除率大于99%,COD去除率大于90%,膜通量水洗恢复率大于93%。     

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。