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1.
双氧水氧化盐湖卤水脱色的研究   总被引:1,自引:0,他引:1  
为降低色度对盐化工产品质量的影响,提高盐湖卤水综合利用的产品附加值,基于盐湖卤水理化特性,研究了双氧水氧化法对盐湖卤水中有色物质的去除效果,确定了双氧水氧化脱色的最佳工艺条件为:卤水PH调节至2,加入3%(质量分数)双氧水,于40℃加热搅拌氧化120 min.在此条件下盐湖卤水脱色率达到60%.脱色处理后的卤水色度明显降低,透明度增加.通过对氧化前后卤水有机物表观相对分子质量变化对比发现:相对分子质量大于30 ku的有机物所占比例明显增多,相对分子质量在3~30 ku的有机物减少.  相似文献   

2.
给水处理工艺中有机物选择性去除研究   总被引:2,自引:0,他引:2  
以中试试验为基础,对珠江微污染水深度处理工艺各工艺段出水进行了有机物含量及分子质量分布的测定.结果表明,各工艺段对有机物去除有选择性规律,生物预处理和臭氧化将大分子有机物转化为小分子有机物,生物预处理有效去除分子质量>30 k和10 k~3 k有机物,而分子质量介于30 k~10 k和3 k~1 k有机物大幅度升高,总体去除率不高;给水常规工艺基本能将分子质量10 k以上有机物去除,但对小分子有机物基本没有去除效果;臭氧氧化对分子质量介于3 k~1 k有机物去除明显,BAC能将分子质量小于1 k的有机物有效去除.  相似文献   

3.
进行了强化混凝法去除腈纶废水中COD的研究。结果表明,铁碳微电解预氧化可提高混凝处理效果。通过对分子质量分布、Zeta电位及核磁共振波谱的测定发现,铁碳微电解的氧化作用可导致大分子有机物降解为小分子有机物,小分子有机物矿化,因此提高了分子质量50 ku和3 ku的有机物去除率;微电解产生的Fe2+有电性中和作用,使Zeta电位降低,强化混凝效果;微电解的氧化作用主要破坏酯类和醚类结构。  相似文献   

4.
以再生水循环利用过程中可能富集的污染物为对象,通过对比研究"臭氧-生物活性炭"(O3-BAC)与"强化混凝-沉淀-过滤"这两种工艺对水中污染物的去除特性,得到两种工艺对水中污染物色度、氨氮和总氮、总磷等的去除结果,以及臭氧氧化出水相对分子质量和有机物分子结构的变化情况。研究结果表明O3-BAC工艺对有机物、色度、氮、磷等污染物具有更好的处理效果,是适合于再生水循环利用系统水质保障的污水深度处理工艺。  相似文献   

5.
采用混凝沉淀工艺处理污水处理厂二级出水,通过投加聚合氯化铝(PAC)和聚硫氯化铝(PASC)混凝剂,分析混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、氨氮、总氮、总磷等指标的去除效果,并找到最佳的处理试剂及投加量。结果表明,混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、总磷具有很好的去除效果,氨氮和总氮的去除效果不佳,投加混凝剂会增加二级出水离子含量,导致电导率增加。聚硫氯化铝的混凝效果较聚合氯化铝好,对于有机物、色度等指标,达到相同混凝效果,聚硫氯化铝投加量仅约聚合氯化铝的一半,两者的最佳投加量分别为40 mg/L和80 mg/L。  相似文献   

6.
采用混凝沉淀工艺处理污水处理厂二级出水,通过投加聚合氯化铝(PAC)和聚硫氯化铝(PASC)混凝剂,分析混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、氨氮、总氮、总磷等指标的去除效果,并找到最佳的处理试剂及投加量。结果表明,混凝沉淀工艺对污水处理厂二级出水浊度、有机物、色度、总磷具有很好的去除效果,氨氮和总氮的去除效果不佳,投加混凝剂会增加二级出水离子含量,导致电导率增加。聚硫氯化铝的混凝效果较聚合氯化铝好,对于有机物、色度等指标,达到相同混凝效果,聚硫氯化铝投加量仅约聚合氯化铝的一半,两者的最佳投加量分别为40 mg/L和80 mg/L。  相似文献   

7.
新型滤料-活性无烟煤及其过滤工艺研究   总被引:1,自引:0,他引:1  
活性无烟煤同时具有过滤性能和活性吸附性能。通过小试和中试试验利用沉淀池出水进行了过滤比较研究。试验结果表明,活性无烟煤对浊度的去除效果优于柱状活性炭,与石英砂或者普通无烟煤相当,去除效率在75%以上。活性无烟煤对有机物的去除效率,与柱状活性炭类似,而显著优于石英砂和普通无烟煤。活性无烟煤表面有着丰富的孔隙结构,孔径分布范围较广,有利于对不同大小分子的有机物吸附去除。活性无烟煤能够使传统的过滤工艺具备一定的深度处理功能,适合处理微污染水,这对于传统给水水厂工艺的改造具有重要的现实意义。  相似文献   

8.
生物活性炭工艺去除长江原水中有机成分的研究   总被引:1,自引:1,他引:0  
以长江南京段原水为研究对象,以提高水处理出水水质和生物稳定性为目标,研究了生物活性炭工艺对有机物指标和氯苯类化合物的去除效果,并从有机物分子量的角度研究了生物活性炭工艺对有机物的去除机制。中试试验结果表明:生物活性炭工艺能有效地去除水中的有机物,对CODMn,UV254,溶解性有机碳(DOC)及可生物降解溶解性有机碳(BDOC)的去除率可分别达到52%,50%,40%和82%,对氯苯类化合物的去除效果也较为明显,去除率为40%左右。生物活性炭工艺对各个分子量区间的去除效果都比较好,对原水中占多数的小于1k的溶解性有机物(DOM)去除效果尤为显著。  相似文献   

9.
介绍某水厂采用"臭氧-生物活性炭-砂滤"深度处理组合工艺处理引黄水库水,考察了不同进水浑浊度对组合工艺长期运行效果的影响,同时对组合工艺各单元的有机物种类及分子量分布的变化进行了分析。长期运行结果表明:(1)组合工艺对不同水质条件下的有机物指标有较高的去除效果,较高的温度有利于水中有机污染物的去除。(2)臭氧的主要作用在于将大分子量的有机物氧化为小分子量有机物,故臭氧生物活性炭工艺对COD_(Mn)2、UV_(254)和DOC有良好的去除作用。整个工艺对氨氮的去除率在40%~50%,对亚硝酸盐氮的去除率在80%~90%。(3)臭氧活性炭工艺对可生物降解有机物有较好的去除效果,砂滤工艺主要去除D0CDA。(4)上向流BAC柱活性炭颗粒间空隙率较大,降低了对浊度的机械截留,其后置的砂滤池可起到稳定出水浊度,保证出水微生物安全性的作用。  相似文献   

10.
考察了4种超滤组合工艺(精滤-超滤、精滤-活性炭-超滤、精滤-活性炭-精滤-超滤和混凝沉淀-超滤)对城市污水的深度处理效果.结果表明,4种超滤组合工艺对浊度的去除率都很高,最高达92.2%,均能保证出水浊度低于1 NTU,说明超滤膜对浊度的去除效果很好;4种超滤组合工艺对有机物的去除率比较高,其中精滤-活性炭-精滤-超滤对有机物的去除效果最好;超滤膜对TN和NH_3-N的去除率比较低;4种超滤组合工艺的初始膜通量不同,精滤-活性炭-精滤工艺出水通量下降较快.  相似文献   

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12.
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.  相似文献   

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14.
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.  相似文献   

15.
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.  相似文献   

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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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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