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1.
采用反相悬浮法,以戊二醛为交联剂,以环己烷为致孔剂制备交联壳聚糖微球树脂(CCMR);通过静态吸附试验研究树脂对Cu(Ⅱ)的吸附行为。利用金相显微镜和比表面积仪对交联壳聚糖微球树脂(CCMR)的表观形貌和比表面积进行表征;通过紫外可见光谱考察了Cu(Ⅱ)初始浓度对吸附性能影响,研究其吸附动力学。结果表明,随着致孔剂用量的增加,交联壳聚糖微球树脂比表面积增大,吸附性能增强,其中添加环己烷100 m L,乙酸乙酯5 m L制备交联壳聚糖微球树脂对浓度为8 mg/m L的Cu(Ⅱ)溶液的平衡吸附容量可达190 mg/g,吸附性能较好,吸附过程符合准二级吸附动力学模型。  相似文献   

2.
李继平  崔艳  韩吉慧  常国彬 《辽宁化工》2003,32(11):469-471
以羧甲基壳聚糖为原料,经戊二醛交联,制备阳离子型树脂。考察了其对稀土离子Eu^3 的吸附性能,探讨了溶液的酸度、初始离子浓度、反应时间及离子强度对该树脂吸附性能的影响;发现羧甲基壳聚糖经戊二醛交联制成的树脂对Eu3^ 有较强的吸附性能,可达到95%且吸附速度快,并且具有良好的使用性。  相似文献   

3.
以壳聚糖为原料,戊二醛为交联剂制备交联壳聚糖凝胶,并对凝胶的溶胀性能及Ni~(2+)吸附效果进行研究。实验结果表明,交联剂用量越大,交联密度越高,但是凝胶网络弹性降低,溶胀性变差;弱酸至中性条件有利于凝胶的溶胀,交联改性能降低壳聚糖的溶胀热敏温度,降低后期吸附Ni~(2+)的能耗。用1%的戊二醛交联壳聚糖处理20、40 mg/L Ni~(2+)电镀废水,投加60 mg交联改性壳聚糖,在30℃、p H=7条件下吸附3 h,吸附率分别达96.9%和92.4%,吸附过程可用一级动力学模型进行模拟。废水经过二次吸附后出水水质均能达到0.01 mg/L Ni~(2+)的《污水综合排放标准》(GB3838)标准,交联改性壳聚糖的重复使用性好,多次循环使用后依然具有很好的吸附效果。  相似文献   

4.
以戊二醛作为交联剂,氯化铝、二氧化钛为掺杂剂对壳聚糖进行交联聚合改性,制备改性壳聚糖,通过IR、XRD的表征和等温吸附曲线确定掺杂二氧化钛、氯化铝的交联壳聚糖具有较好的吸附效果,再通过正交实验研究温度、染料浓度、时间、吸附剂用量等因素对该改性壳聚糖吸附茜素红、活性红的影响,试验结果表明:用该改性壳聚糖吸附茜素红,当茜素红浓度为40mg/L,温度为35℃,改性壳聚糖用量为1.5g,吸附时间为20min,脱色率91.1%,CODCr去除率79.1%;当活性红浓度为40mg/L,温度为20℃,改性壳聚糖用量为2.0g,吸附时间为30min,脱色率99.9%,CODCr去除率82.2%.  相似文献   

5.
张娟  吴洁  冯辉霞  许培 《现代化工》2011,31(9):56-58,60
以鞣酸为模板,采用乳化交联法制备了鞣酸模板交联壳聚糖/凹土复合树脂(TA-CS/ATP)。采用扫描电子显微镜(SEM)和傅里叶变换红外光谱仪(FT-IR)分别对树脂形貌和结构进行表征,用孔参数对其性能进行评价。考察了模板分子的加入量对树脂吸附容量的影响,并根据洗脱率对模板洗脱液进行选择。结果表明:与非模板树脂相比,当壳聚糖与模板的质量比为1.00∶0.05时,树脂的孔度值和膨胀率分别从48%和57.41%提高到79%和87.05%,吸附容量由314.7 mg/g增加到445.7 mg/g。树脂的再生性能研究表明,凹土和模板分子的加入,使树脂在酸中的失重率从18.45%降低到6.18%,且树脂经过4次再生使用仍然具有较高的吸附容量。  相似文献   

6.
王丽丽  苏苗  林强 《化学世界》2012,53(4):201-203
采用反相悬浮法合成了羧甲基壳聚糖球形凝胶树脂,平均粒径为0.338mm。考察了槲皮素溶液浓度、吸附时间和温度、戊二醛用量以及交联温度对树脂吸附性能的影响。结果表明,槲皮素溶液浓度对吸附量有较大影响,最大吸附量可达38.1mg/g,其它因素对吸附量也有一定影响。  相似文献   

7.
交联羧甲基壳聚糖树脂对稀土离子吸附性能研究   总被引:3,自引:0,他引:3  
以羧甲基壳聚糖为原料,经戊二醛交联制备阳离子型树脂,考察了其对稀土离子La^3 、Nd^3 、Sm^3 、Lu^3 吸附性能。探讨了溶液的酸度、体系温度、初始离子浓度及离子强度对该树脂吸附性能的影响;发现羧甲基壳聚糖经戊二醛交联制成的树脂对稀土离子有较强的吸附性,最高吸附率可达99%以上,并且具有良好的重复使用性;其吸附性为满足Langmuir或Freumdilich等温式。  相似文献   

8.
以戊二醛为交联剂,将β-环糊精交联到壳聚糖大分子链上,制备出新型环境功能吸附材料壳聚糖交联β-环糊精(CTS-CD),并研究了CTS-CD对水中镉的吸附研究。实验结果表明,CTS-CD对镉的吸附受溶液pH的影响较大,吸附效果在pH=5左右时最佳,当含镉水溶液初始浓度小于10 mg/L时,2. 5 h吸附趋于平衡;当初始浓度大于20 mg/L时,4. 5 h吸附趋于平衡,平衡吸附容量趋于定值,其数值为121 mg/g。  相似文献   

9.
采用纤维素与壳聚糖复合的方法,以戊二醛为交联剂制备了一种具有Cu2+印迹的纤维素/壳聚糖复合微球,考察了制备过程中纤维素种类,纤维素与壳聚糖质量比、戊二醛用量、交联时间、交联温度及溶液pH对吸附铜(Ⅱ)的影响,并用扫描电镜(SEM)和傅里叶红外光谱(FTIR)对复合微球进行表征.结果表明,当壳聚糖与羧甲基纤维素质量比为...  相似文献   

10.
以壳聚糖为原料制备交联壳聚糖吸附剂,并将其用于吸附废水中的Cu2+,考察了交联剂的用量、溶液中Cu2+初始浓度、pH、温度和时间等对交联壳聚糖吸附性能的影响。结果表明,壳聚糖与交联剂的用量比为m(壳聚糖)∶V(甲醛)∶V(戊二醛)=1.5g∶6mL∶4.5mL、溶液pH为6,溶液中Cu2+初始浓度为5mmol/L时吸附效果最佳,且吸附量随着温度升高而增加,吸附表现为吸热过程。  相似文献   

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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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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   

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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   

18.
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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