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1.
采用化学氧化聚合法制备磁性壳聚糖/聚苯胺染料吸附剂,研究了pH值、吸附时间和甲基橙染料初始质量浓度对磁性壳聚糖/聚苯胺吸附剂甲基橙染料吸附性能的影响,对磁性壳聚糖/聚苯胺吸附剂甲基橙吸附过程进行热力学等温线和动力学研究,并对磁性壳聚糖/聚苯胺的磁滞性能进行了研究。结果表明,磁性壳聚糖/聚苯胺的饱和磁化强度达16.7 emu/g,显示其具有较好的磁响应性能和磁分离性能,90 min甲基橙的吸附趋于平衡,随着甲基橙初始质量浓度的增加,甲基橙的吸附容量呈现不断增大但增幅趋缓的趋势。随着pH值的增加,甲基橙染料的吸附容量呈现不断降低的趋势。磁性壳聚糖/聚苯胺甲基橙吸附等温线遵循Freundlich方程,甲基橙吸附动力学满足准二级动力学方程。  相似文献   

2.
本文利用盐酸对活性炭进行了改性,并研究其对甲基橙的吸附性能.主要考察了吸附剂用量、甲基橙的初始浓度、吸附温度和吸附时间等因素对甲基橙吸附性能的影响,确定了盐酸改性活性炭吸附甲基橙的最佳工艺条件.结果表明,吸附剂用量30 mg、甲基橙初始浓度60 mg/L、吸附温度40℃、吸附时间8 h的条件下,改性活性炭对甲基橙的吸附...  相似文献   

3.
采用共沉淀法制备Fe3O4@ABc复合材料,通过XRD、SEM、FT-IR和VSM 对Fe3O4@ABc复合材料的物化性质进行表征。考察吸附实验pH值、吸附剂添加量等因素对Fe3O4@ABc 复合材料对甲基橙吸附效果的影响,并进行了吸附动力学和等温吸附模型拟合。结果表明,Fe3O4纳米粒子成功复合到海藻生物炭(ABc)表面,Fe3O4@ABc复合材料具有超顺磁性,在外在磁场的作用下能够快速分离;Fe3O4@ABc比表面积为622.88 m2?g-1,平均孔径1.56 nm,具有良好的甲基橙去除效果,当甲基橙浓度为100 mg?L-1,添加量为10 mg,pH值为3,吸附时间240 min,MO的去除率为96.14 %, Fe3O4@ABc重复利用五次后,甲基橙的去除率为94.24 %。吸附机制研究发现吸附等温线数据拟合符合Freundlich 模型,吸附动力学数据拟合符合拟一级动力学模型,说明吸附以物理为主,化学吸附为辅。  相似文献   

4.
杨梅  孙润军  王红红 《合成纤维》2019,48(1):15-20,36
以静电纺丝制备的壳聚糖(CS)/聚乙烯醇(PVA)纳米纤维膜为吸附剂,研究了反应时间、甲基橙初始质量浓度、膜吸附剂用量和pH值对吸附甲基橙染料的影响,并通过吸附动力学行为和吸附等温线研究了其吸附机制。结果表明:当pH值在5~9之间、甲基橙初始质量浓度为100 mg/L、吸附剂用量为30 mg、反应时间为60~120 min之间时,吸附效果最佳且吸附平衡时间为3 h;CS/PVA膜对甲基橙的吸附既有物理吸附也有化学吸附,化学吸附占主导作用,CS/PVA膜对甲基橙的吸附符合Langmuir等温线和拟二级动力学模型。  相似文献   

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本文提出了将海藻酸钠和纳米Fe3O4以物理共混的方法,制备一定粒度的磁性海藻酸钠凝胶球.以持久性有机污染物甲基橙(methyl orange,简写MO)为研究对象,考察了初始pH值、磁性凝胶球的加入量、MO初始浓度和吸附时间等因素对吸附效果的影响;同时对吸附过程进行等温式和动力学拟合,初步分析了吸附机理.结果表明:利用纳米Fe3O4比表面积大和表面原子配位不足的特点,制备的磁性凝胶球对MO的吸附率可达90%以上;磁性凝胶球对持久性污染物MO的吸附遵循Langmuir等温方程和准二级反应动力学,说明吸附过程为单分子层吸附和化学吸附作用为主.在外加磁场作用下,纳米Fe3O4粒子超顺磁性有助于吸附剂能快速有效地从液相分离.经4次重复使用后,磁性凝胶球对MO仍具有很好的吸附效果,可进行多次重复使用.  相似文献   

6.
采用水热法合成了Fe3O4@MOF-199@C18磁性纳米材料,并以此为吸附剂进行对亚甲基蓝的吸附实验,考察了Fe3O4@MOF-199@C18材料的吸附性能。通过红外光谱、扫描电镜、透射电镜等手段对该磁性材料进行了表征,结果表明此合成材料为质地均匀、表面多孔的磁性纳米材料。Fe3O4@MOF-199@C18磁性纳米材料吸附亚甲基蓝的最佳吸附条件为:pH为4,振荡时间为35 min,材料用量为5 mg,亚甲基蓝初始浓度为3 mg/L时,Fe3O4@MOF-199@C18磁性纳米材料对亚甲基蓝的吸附量为12.81 mg/g。重复利用实验结果表明,Fe3O4@MOF-199@C18材料至少可以重复利用7次。  相似文献   

7.
通过化学交联法制备了纯壳聚糖膜和壳聚糖/活性炭纤维复合膜(质量比为1∶1.1);探讨时间、pH值、温度、甲基橙溶液初始浓度以及吸附剂用量对吸附甲基橙的影响。研究结果表明,最佳吸附时间为120 min,在pH为6.0,甲基橙初始浓度10 mg/L,温度为10℃时,膜对甲基橙的吸附效果最好,去除率达99.54%。  相似文献   

8.
以四甲基溴化铵(TAB)和聚二烯丙基二甲基氯化铵(PDMDAAC)为改性剂,对天然钠基膨润土进行双阳离子复合改性,制得低成本吸附剂双阳离子复合改性膨润土(T/P-PRT)。用FTIR、BET等手段进行表征,考察了吸附剂用量、初始pH、吸附温度、接触时间等因素对水中偶氮染料甲基橙(MO)的去除效果影响。结果表明,膨润土经改性后,比表面积和孔容变小,平均孔径增大。T/P-PRT对MO的最佳吸附条件为MO初始浓度为500 mg/L、溶液pH为4、吸附剂用量为10 g/L、反应温度为298 K、吸附时间为480 min。在此最佳吸附条件下,吸附量和去除率都达到了最大值,分别为42.66 mg/g和85.33%。MO在T/P-PRT上的吸附过程更符合准二级动力学模型和Langmuir等温模型,吸附过程为化学单层吸附和放热反应。  相似文献   

9.
本文采用简单的一步热聚合法制备了钴掺杂碳基材料Co3O4-g-C3N4,并对其作为吸附剂的性能进行研究。所制备的材料通过XRD、XPS、BET对晶体结构、形貌、价态分布、比表面积以及孔径分布进行表征分析,实验以甲基橙为目标污染物进行吸附,其最大平衡吸附容量为118.83mg/g。Co3O4-g-C3N4吸附剂对甲基橙溶液吸附的动力学符合准二级动力学模型,吸附等温线符合Langmuir等温线。  相似文献   

10.
《应用化工》2022,(11):2309-2313
探究生物基活性炭对有机-水共混溶剂中的甲基橙的吸附性能、吸附平衡和动力学研究。结果表明,生物基活性炭对甲基橙的最大单层吸附量为80. 4 mg/g。相比准一级动力学模型,准二级动力学模型更适合于描述有机-水共混溶剂中活性炭吸附甲基橙的过程。  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   

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   

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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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