氯化铝絮凝剂处理煤气脱硫碱液的研究

采用氯化铝絮凝剂处理煤气脱硫碱液,探讨了氯化铝浓度、搅拌速度、pH值、沉降时间等因素对除油效果的影响,考察了这些因素对浊度和色度的去除效果.实验结果表明,氯化铝浓度为800mg/L、搅拌速度为200r/min、沉降时间为3h、pH值为8.0时,除油率、浊度去除率分别达到了56.82％、75.26％,但脱色能力很低.     

三聚氰胺浊度色度测定影响因素及排除方法

测定三聚氰胺浊度和色度时,使用不同厂家生产的甲醛和氢氧化钠试剂及同一厂家生产的不同批次的甲醛和氢氧化钠试剂其pH值和铁含量不同,其pH值和铁含量的大小影响浊度和色度测定结果。经过多次的反复实验,采取调节酸度法、对照试验法和过滤法取得了很好的效果,确保了分析结果的准确性。     

果皮混凝剂的无机改性及其性能研究

为提升果皮混凝剂（HFP）的稳定性,采用硅铁元素对HFP进行改性,制备出无机改性果皮混凝剂（IMHFP）。以模拟生活污水为试验水样,通过混凝试验研究了IMHFP投加量、原水浊度、 pH值、沉降时间对其混凝性能的影响,对比研究了IMHFP与新鲜HFP的混凝性能与稳定性情况,并对混凝机理进行分析。结果表明,IMHFP对于浊度、色度与总磷的去除效果略优于HFP,二者对COD的去除效果基本相当;IMHFP具有更广的pH值适用范围（6～11）。储存一段时间后,IMHFP未出现变质现象,且其除浊和除色效果稳定;而HFP出现颜色加深和腐败现象,除浊率和除色率分别由新鲜HFP的91.21%和81.29%急剧下降至储存35 d后的78.33%和61.37%。     

发酵液中吩嗪-1-羧酸的初步分离工艺

通过考察吩嗪-1-羧酸(PCA)在不同pH值下的溶解度,利用PCA碱溶酸沉的性质,采用絮凝法去除发酵液中的大分子蛋白质和菌丝体等杂质,初步分离出代谢产物PCA;研究了絮凝剂用量、发酵液稀释倍数、pH值及温度对过滤速度、终产品PCA含量和回收率的影响. 结果表明,当以聚氯化铝为絮凝剂、发酵液稀释4倍、絮凝pH值为8.5、絮凝温度为30℃时,所得产品中PCA含量达69.9%,产品对发酵液的PCA回收率为91.3%.     

分光光度法测定水样的色度

水样色度的测定目前还无分光光度法国家标准,主要采用铂钴色标目视比色法和稀释倍数法测定.介绍了用751分光光度计测定污水色度的最佳条件是波长339 nm、3 cm比色皿、配以深紫色滤光片,测定结果的线性相关系数r在0.999 9以上;该方法不仅能准确测定常规水样色度,还可将高色度的污水多倍稀释后进行准确测定.     

印染废水回用色度测定方法探讨

文章简要介绍水样色度的三种测定方法,重点介绍稀释倍数法,结合实际对稀释倍数法的测定过程进行探讨,得出回用印染废水最佳的测定途径,并指出此方法测定的意义。     

不同前处理方法对水质自动监测仪测定总磷的影响分析

针对目前福建省水质自动监测站适逢汛期或降雨量较大时,浊度升高,总磷时常出现超标预警情况,选取不同点位的水体为研究对象,模拟自动站不同前处理方式,探讨不同前处理方式和比色方法对总磷测定结果的影响。分析结果显示：高浊度水体直接比色法与浊度色度补偿法所得结果之间具有显著性差异,样品浊度越高,直接比色法总磷测定值超出浊度色度补偿法越高;采用离心2 min(2000 r/min)的前处理方式不仅测得的总磷值比超声波过滤静置更准确,且比超声波过滤静置和自然静置用时短;离心2 min(2000 r/min)+浊度色度补偿法通过正确度验证。为加快自动监测站测试速度、提高浊度影响下的地表水总磷结果准确度,建议水质自动监测站测定总磷时选用离心2 min(2000 r/min)+浊度色度补偿法。     

带色水体浊度分析方法的研究

研究了浊度与色度的相互关系,针对浊度测定中色度的干扰问题,根据多组分分光光度法测定的原理,提出了不经分离即能同时测定水中浊度和色度的新方法,经过理论推导,建立了计算方程,选择了分析测定的最佳波长.对实际水样的测定结果表明,该方法具有较高的精密度和准确度.     

次氯酸钠—硫酸铝联合处理焦化废水的研究

选用硫酸铝与次氯酸钠联合作用处理焦化废水,考察了投加量配比、pH值和温度三个因素对焦化废水中COD和NH3-N去除效果的影响。实验结果表明,反应最佳条件是:硫酸铝投加量为20 g/L,次氯酸钠投加量为90 mg/L,pH值为8,温度为30～40℃,此时色度和浊度明显减弱,COD的去除率可达到59.52%,NH3-N去除率可达到41.27%。     

pH值对强化混凝去除水中微量有机物的影响

通过烧杯试验,分别以聚合氯化铝(PAC)和FeCl3为混凝剂研究了pH值对水中有机物去除的影响。研究结果表明:PAC的最佳投加量为8 mg/L,此时有机物和浊度的去除率分别为51.8%和93.6%;FeCl3的最佳投加量为50 mg/L,此时有机物和浊度的去除率分别为57.8%和95.0%。有机物去除的最佳pH值范围为5.5～6.5,浊度去除的最佳pH值范围为7～8;相对于原水而言,调节pH值能够使有机物的去除率提高10%左右,因此调节pH值是一种经济有效的去除水中有机物的强化混凝方法。     

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。