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1.
采用浸渍-焙烧法制备了Fe/Ti O2-Al2O3、Fe/Ce O2-Al2O3复合催化剂,以H2O2作为氧化剂,对亚甲基蓝废水进行降解处理,考察了催化剂加入量、H2O2加入量、p H、温度以及初始浓度的变化等因素对处理效果的影响。结果表明:Fe/Ti O2-Al2O3的催化性能稍优于Fe/Ce O2-Al2O3,并且在p H=5,温度为65℃条件下,当催化剂加入量为0.15 g、H2O2加入量为15 m L、反应时间为60 min时降解率即可达到97%以上。  相似文献   

2.
采用溶胶-凝胶法制备了银氮共掺杂光催化剂Ag-N-Ti O2/膨润土,通过XRD和FTIR对其结构进行了表征,优化了该催化剂降解耐酸枣红染料废水的反应条件。结果表明,催化剂中有锐钛矿型Ti O2生成,部分Ti O2进入了膨润土层间,增大了其晶面层间距,并通过Ti—O—Si键实现了膨润土对Ti O2的固载;掺杂的Ag、N可能进入了Ti O2晶格,拓宽了其光谱响应范围,并提高了其光催化活性。当催化剂用量为2 g/L,溶液p H为3,光照时间为120 min,紫外光或可见光照射下,该催化剂对50 mg/L的耐酸枣红的降解率分别达到93.0%和89.3%,并在可见光下对其它3种50 mg/L的染料废水的降解率也达到了90%以上。  相似文献   

3.
朱鹏飞  刘梅  杨雨  王迪 《应用化工》2015,(3):494-497,505
采用溶胶-凝胶法制备了银氮共掺杂光催化剂Ag-N-Ti O2/膨润土,通过XRD和FTIR对其结构进行了表征,优化了该催化剂降解耐酸枣红染料废水的反应条件。结果表明,催化剂中有锐钛矿型Ti O2生成,部分Ti O2进入了膨润土层间,增大了其晶面层间距,并通过Ti—O—Si键实现了膨润土对Ti O2的固载;掺杂的Ag、N可能进入了Ti O2晶格,拓宽了其光谱响应范围,并提高了其光催化活性。当催化剂用量为2 g/L,溶液p H为3,光照时间为120 min,紫外光或可见光照射下,该催化剂对50 mg/L的耐酸枣红的降解率分别达到93.0%和89.3%,并在可见光下对其它3种50 mg/L的染料废水的降解率也达到了90%以上。  相似文献   

4.
以Ti(C4H9O)4为前驱体,CH3COOH为水解抑制剂,通过溶胶-凝胶法制备了TiO_2/Fe2O3复合光催化剂。对复合光催化剂的光催化活性、光催化机理和光催化降解动力学进行了研究。研究表明,Fe2O3的引入有助于光生电子-空穴对的分离,从而提升TiO_2的光催化活性。TiO_2/Fe2O3的光催化降解动力学符合L-H动力学模型的一级反应方程模型,整个光催化反应的控制步骤为降解物在光催化剂表面的有效吸附,动力学反应级数随着降解物浓度的上升而逐渐下降。  相似文献   

5.
以Ti(C4H9O)4为前驱体,CH3COOH为水解抑制剂,通过溶胶-凝胶法制备了TiO_2/Fe2O3复合光催化剂。对复合光催化剂的光催化活性、光催化机理和光催化降解动力学进行了研究。研究表明,Fe2O3的引入有助于光生电子-空穴对的分离,从而提升TiO_2的光催化活性。TiO_2/Fe2O3的光催化降解动力学符合L-H动力学模型的一级反应方程模型,整个光催化反应的控制步骤为降解物在光催化剂表面的有效吸附,动力学反应级数随着降解物浓度的上升而逐渐下降。  相似文献   

6.
以PW11/PANI/Ti O2为光催化剂,研究了不同条件对亚甲基蓝光催化降解效果的影响,如改变亚甲基蓝溶液的起始浓度、调节溶液的起始p H值和催化剂的用量等。结果表明,亚甲基蓝溶液光催化降解的最佳条件为染料的起始质量浓度为10 mg/L,p H值为3,催化剂的最佳用量为7.5mg,可达90.12%的脱色率。该催化剂对亚甲基蓝染料的降解为一级动力学反应。  相似文献   

7.
马宏勋  董金龙 《陕西化工》2011,(1):49-50,54
采用浸渍法制备了H4SiW12O40/TiO2-ZrO2光催化剂,以光催化降解染料废水甲基橙为探针反应,探讨了催化剂投加量、溶液pH值对光催化降解效果的影响以及催化剂的重复使用性。结果表明,H4SiW12O40/TiO2-ZrO2催化剂具有更优越的光催化性能,当催化剂的用量为1.8 g/L,甲基橙溶液初始浓度为10 mg/L,pH=4时,反应4 h后甲基橙的降解率可达90%以上。  相似文献   

8.
采用溶胶-凝胶法制备了Ce3 /TiO2光催化剂,研究了该催化剂对亚甲基蓝的光催化降解效果.结果表明掺杂量w(Ce3 )3.7%,催化剂用量0.12 g·L-1,体系pH值为10,12 mg·L-1亚甲基蓝溶液经2 h光催化降解,其降解率可达98.87%,与纯TiO2相比,Ce3 /TiO2光催化剂显示出良好的光催化活性.  相似文献   

9.
马宏勋  董金龙 《应用化工》2011,40(1):49-50,54
采用浸渍法制备了H4SiW12O40/TiO2-ZrO2光催化剂,以光催化降解染料废水甲基橙为探针反应,探讨了催化剂投加量、溶液pH值对光催化降解效果的影响以及催化剂的重复使用性。结果表明,H4SiW12O40/TiO2-ZrO2催化剂具有更优越的光催化性能,当催化剂的用量为1.8 g/L,甲基橙溶液初始浓度为10 mg/L,pH=4时,反应4 h后甲基橙的降解率可达90%以上。  相似文献   

10.
采用浸渍法制备了H6P2W18O62/Ti O2-Si O2光催化剂,并采用傅里叶变换红外光谱(FTIR)、X射线粉末衍射(XRD)、扫描电子显微镜(SEM)对其进行了表征。通过光催化剂H6P2W18O62/Ti O2-Si O2对含甲基橙模拟废水进行处理,结果表明,H6P2W18O62/Ti O2-Si O2光催化剂表现出较高的光催化性能,在催化剂用量为1.39 g/L,甲基橙溶液质量浓度为5 mg/L,初始p H=3.5,反应时间2.5 h的条件下,甲基橙的降解率可达99.2%,且产生了协同效应。H6P2W18O62/Ti O2-Si O2光催化剂对罗丹明B、亚甲基蓝和甲基红均具有较高的光催化性能,降解率达84.0%~100.0%。光催化剂还表现出较好的重复使用性能,第5次降解率仍为94.4%。  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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