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1.
成岳  苏晓渊 《陶瓷学报》2010,31(1):122-125
以叠氮化钠为氮源、硅溶胶为硅源、钛酸四丁酯为钛源,按2.5N∶65Ti∶100SiO2∶12Na2O∶2Al2O3∶2500H2O的摩尔比,采用静态水热合成法合成了N-Ti-ZSM-5分子筛,并采用XRD、TEM等对分子筛样品进行了表征。研究了所合成的分子筛的光催化性能,考察了催化剂的含氮量、催化剂的投加量、pH值以及光源等因素对光催化降解亚甲蓝的影响。并在可见光下处理10mg/L的亚甲基蓝,光催化20min,脱色率和降解率分别达到了75.84%和76.68%,取得了良好的效果。  相似文献   

2.
本文以化学沉淀法制备了Cu_2O/蒙脱土复合光催化剂,以亚甲基蓝的光催化降解为探针反应测试了Cu_2O/蒙脱土复合催化剂的光催化活性,并研究了Cu_2O的负载量、复合催化剂用量、溶液pH值和亚甲基蓝初始浓度等对Cu_2O/蒙脱土复合催化剂光催化活性的影响。研究结果表明pH=11、50%Cu_2O/蒙脱土复合催化剂投加量为0.2g/L、亚甲基蓝溶液浓度为10mg/L时,可见光照射120min后,降解效率可达到91%。  相似文献   

3.
史剑  马荣华 《化工时刊》2012,26(1):15-17
以α-SiW11Ni/PANI为催化剂,在紫外灯辐射下,研究了模拟染料废水亚甲基蓝溶液的光催化降解的反应,讨论了催化剂投加量、亚甲基蓝溶液的初始浓度、酸度等对催化脱色效果的影响。实验结果表明,100 mL的亚甲基蓝溶液在紫外灯辐射下最佳的浓度为5 mg/L,催化剂用量为110 mg/L,溶液酸度为pH2;在不改变溶液酸度的情况下,外加氧化剂H2O2能够显著加速亚甲基蓝的催化降解效果。  相似文献   

4.
Ce-MCM-48介孔材料的合成与吸附性能研究   总被引:1,自引:0,他引:1  
采用Ce2O3∶SiO2∶CTAB∶H2O∶NaOH=0.015∶1∶0.45∶60∶0.48的摩尔配比,用水热法合成了Ce-MCM-48介孔分子筛。试验结果表明,经550℃焙烧过的Ce-MCM-48分子筛吸附性能良好,投加量为1.2g/L,亚甲基蓝初始浓度5.0mg/L,吸附时间为3小时,溶液的pH值为7时,亚甲基蓝溶液的脱色率和降解率分别高达98.90%和86.89%。并采用XRD,TEM、EDS等方法对Ce-MCM-48样品进行了表征。  相似文献   

5.
以预处理过的煤矸石为硅源、铝源,四丙基溴化铵为模板剂,采用常规水热合成法制得ZSM-5分子筛,并采用XRD、SEM、DTA/TGA等对所合成的分子筛进行了分析表征.用合成的ZSM-5分子筛吸附降解亚甲基蓝.发现亚甲基蓝的初始浓度为1.0mg/L、ZBM-5分子筛的投加量为0.02g、吸附时问为3小时、pH值为中性左右时降解效果较好,脱色率和降解率分别达到98.23%、95.16%.  相似文献   

6.
制备了Ce掺杂的TiO2复合SiO2光催化剂(Ce-TiO2/SiO2),使用该光催化剂在模拟太阳光下催化降解亚甲基蓝水溶液,研究了催化剂用量、亚甲基蓝初始质量浓度、溶液pH、无机阴离子对光催化降解效果的影响。结果表明:n(Ce)∶n(Ti)∶n(Si)=0.002∶1∶1时所制催化剂的光催化活性最好;对于2.5 mg/L、pH为11的亚甲基蓝溶液,投加100 mg/L的光催化剂反应2 h可达到最高降解率(92.6%);NO3-、SO42-、Cl-的存在对光催化降解具有抑制作用。  相似文献   

7.
利用谷壳制备的二氧化硅为硅源、六亚甲基亚胺(HMI)为模板剂,按SiO2∶0.5HMI∶0.033Al2O3∶0.36NaOH∶40H2O的摩尔比,采用静态水热合成法合成了具有MWW层状结构的MCM-49分子筛,并采用XRD、TEM等手段对合成分子筛进行了表征。研究了所合成的分子筛对阳离子红X-5GN的吸附性能,考察了分子筛的投加量、反应环境的pH值、吸附时间等因素对吸附阳离子红X-5GN模拟染料废水的影响。在MCM-49分子筛的投加量为1.4g/L,pH为10,振荡时间为60min的实验条件下,脱色率以及降解率分别达到了69%和70.1%,取得了良好的效果。  相似文献   

8.
以PW12/PANI/ZnO为光催化剂。在紫外灯辐射下,研究了模拟染料废水亚甲基蓝溶液的光催化降解的反应,讨论了催化剂投加量、染料浓度、溶液的pH值对亚甲基蓝降解率的影响。结果表明,亚甲基蓝溶液光催化降解的最佳条件为:pH=3,催化剂投加量为0.012 5 g,染料浓度为5 mg/L,经30 W紫外灯照射90 min后,其降解率为85.84%。  相似文献   

9.
采用溶胶-凝胶法制备了FeCoCa三种元素的氧化物纳米晶.采用XRD,SEM对催化剂进行表征,同时研究了亚甲基蓝催化剂与H2O2的协同降解作用.结果表明:FeCoCa氧化物纳米晶和H2O2组成的Fenton反应可以有效地降解亚甲基蓝溶液;当铁钴钙三种元素的摩尔比例为1∶i.5∶3.5,催化剂投加量为1.2 g/L,过氧化氢投加量为0.7mL,初始pH值为6.80,亚甲基蓝的降解率达到93%;与传统Fenton反应体系相比,溶出铁的量降低到0.18 mg/L.  相似文献   

10.
成岳  苏晓渊  焦创 《硅酸盐通报》2011,30(5):1208-1211
采用静态水热晶化法,以硅溶胶为硅源、六亚甲基亚胺(HMI)为模板剂,通过掺杂Ce合成了具有MWW层状结构的Ce-MCM-22分子筛.利用粉末X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)等方法对其进行了表征,考察了各种因素对Ce-MCM-22分子筛吸附亚甲基蓝溶液的影响,结果表明当Ce-MCM-22分子筛的投加量为0.6 g/L,亚甲基蓝浓度为2.0 mg/L,pH值为7,震荡60 min时,吸附脱色效果较好.  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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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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