Bi0/Bi2O2CO3/N-TiO2复合材料的制备及其光催化性能

利用TiO2纳米带作为基底,乙二胺作为还原剂及氮源,采用溶剂热法合成光催化复合材料Bi0/Bi2O2CO3/N-TiO2.通过XRD、SEM、TEM等对催化剂的结构进行了表征.结果显示,直径为1.2～2.1 nm的单质铋(Bi0)和碳酸氧铋(Bi2O2CO3)的复合量子点均匀生长在一维TiO2纳米带(TiO2 NBs)表面.在可见光照射下,相比于TiO2 NBs(降解率30.95％),Bi0/Bi2O2CO3/N-TiO2在3 h内实现了对有机污染物罗丹明B的高效降解(降解率95.02％).活性物质捕获实验证实,h+和?OH是材料参与光催化降解罗丹明B的主要活性物质.     

Bi0/Bi2O2CO3/N-TiO2复合材料的制备及其光催化性能

利用TiO2纳米带作为基底,乙二胺作为还原剂及氮源,采用溶剂热法合成光催化复合材料Bi0/Bi2O2CO3/N-TiO2。通过XRD、SEM、TEM等对催化剂的结构进行表征,结果显示,直径为1.2~2.1 nm的单质铋（Bi0）和碳酸氧铋（Bi2O2CO3）的复合量子点均匀生长在一维TiO2纳米带（TiO2 NBs）表面。在可见光照射下,相比于TiO2（降解率30.95％）,Bi0/Bi2O2CO3/N-TiO2在3 h内实现了对有机污染物罗丹明B的高效降解（降解率95.02％）。最后进行活性物质捕获实验,证实h+和•OH是材料参与光催化降解罗丹明B的主要活性物质。     

水热法合成硫化铋及其光催化性能

以硝酸铋(Bi(NO3)3·5H2O)和硫脲((NH2)2CS)为原料,采用尿素((NH2)2CO)作为矿化剂,低温水热合成硫化铋(Bi2S3)光催化剂,并利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外-可见吸收光谱(UV-Vis)等手段对其进行表征。结果表明:生成了纯的Bi2S3,结晶良好,对光的吸收峰产生了蓝移,带隙能量由体相的1.3 e V增大到1.88 e V。光催化降解罗丹明B的结果表明:引入矿化剂((NH2)2CO)提高了Bi2S3的活性。当矿化剂浓度为1 mol/L、水热反应时间为12 h、水热反应温度为120℃时制备的Bi2S3具有良好的光催化效果,在光辐照150 min后,对初始浓度为10 mg/L的罗丹明B溶液的降解率可达92.3%。     

CoPcS/Bi_2WO_6复合材料的制备及其光催化性能

采用超声复合方法制备了磺化酞菁钴/钨酸铋纳米复合材料,以四环素为降解对象,考察了CoPcS/Bi2WO6复合材料的光催化性能。结果表明,当磺化酞菁钴的掺杂质量为1%时,CoPcS/Bi2WO6对四环素具有较好的光催化活性,反应60 min后,降解率可达80%左右。     

g-C3N4/Bi2MoO6/Ag3PO4复合材料制备及其可见光催化性能

以三聚氰胺、二水合钼酸钠和五水合硝酸铋为原料,采用溶剂热法制备了g-C3N4/Bi2MoO6前驱体,然后通过共沉淀法将Ag3PO4纳米粒子负载在前驱体上,得到g-C3N4/Bi2MoO6/Ag3PO4复合材料。通过XRD、FTIR、XPS、SEM、UV-Vis DRS等对复合材料进行表征。结果表明,g-C3N4、Bi2MoO6和Ag3PO4之间形成了异质结结构,促进光生电子-空穴对的有效分离。以盐酸四环素（TC）为目标降解物,分析材料的光催化活性。在可见光照射下,30 mg g-C3N4/Bi2MoO6/Ag3PO4在50 min内对40 mL 10 mg/L的TC溶液的降解率达到93%。降解速率常数为0.033 min-1,分别是g-C3N4、Bi2MoO6和Ag3PO4降解速率常数的33倍、3.6倍和1.5倍;g-C3N4/Bi2MoO6/Ag3PO4对TC进行降解,循环利用4次后,对TC的降解率为71%,说明g-C3N4/Bi2MoO6/Ag3PO4具有较好的稳定性。自由基捕获实验结果表明,g-C3N4/Bi2MoO6/Ag3PO4光催化降解TC的主要活性物种为·OH和·O2-。最后提出了TC可能的降解机理和降解路径。     

S型Bi OBr/WO3异质结在模拟可见光下高效降解环丙沙星

国家高度重视新污染物治理,抗生素作为重点管控新污染物,其去除技术受到广泛关注,基于光催化降解抗生素的水处理技术成为研究热点。采用水热法制备了WO₃,并采用室温沉淀法成功构建了S型异质结Bi OBr/WO₃光催化剂。与Bi OBr和WO₃相比,S型异质结的形成提高了光催化活性,降低了光生电子空穴对复合率,其中质量分数为20%的Bi OBr/WO₃复合材料光催化性能最好,在120 min内对环丙沙星的降解率可达94.93%。电子自旋共振和自由基捕获实验表明·O₂^–是光催化降解中的主要活性组分。高效液相色谱–质谱联用仪检测结果表明降解过程中产生了6种中间体,并最终矿化为CO₂、H₂O和其他无机离子。     

AgCl/BiOCl纳米片材料的合成及光催化性质研究

以硝酸铋((Bi(NO_3)3·5H_2O)、甘露醇(C_6H_(14)O_6)、氯化钾(KCl)为原料,制备了半导体材料氯氧化铋(BiOCl)纳米片,采用浸渍法负载AgCl对Bi OCl的改性。用XRD,SEM,EDS,UV-Vis光谱等测试方法对样品的结构、形貌、光谱吸收性能等进行了测量分析,考察了不同浸渍次数的AgCl/BiOCl纳米片对罗丹明B(Rh B)染料在可见光下的光催化降解活性。发现适量的AgCl修饰能够提高BiOCl纳米片的光催化活性,当浸渍次数为2次时获得的AgCl/BiOCl复合纳米片具有最好的光催化性能。     

石墨相氮化碳量子点敏化Bi2MoO6复合光催化剂的制备及性能研究

近年来拥有奥里维里斯层状结构的钼酸铋(Bi_2MoO_6)作为高效可见光响应的光催化剂,在净化环境和光催化产氢等领域表现出极为可观的前景,然而光生电子-空穴复合率高等缺陷严重影响了其光催化活性。本文将从两个方面对Bi2_2MoO_6的性能进行优化:一方面通过水热法合成出Bi_2MoO_6纳米片;另一方面,通过与石墨相氮化碳量子点(g-CNQDs)构建异质结,促进光生电子-空穴的分离以达到提高光催化活性的目的。结果表明,当g-CNQDs的投料比为15%时,Bi_2MoO_6/g-CNQDs降解罗丹明B时表现出最高光催化活性,是纯Bi_2MoO_6 的 3.89倍。     

等离子体改性TiO2/WO3/Bi2WO6纳米 复合材料及其可见光催化活性

以二水合钨酸钠和五水合硝酸铋为原料，通过优化水热法反应温度制备了WO3/Bi2WO6纳米片，将其与锐钛矿型TiO2纳米颗粒复合制备了可见光催化性能优良的TiO2/WO3/Bi2WO6复合光催化剂，并采用一种高密度管状等离子体放电装置对其进行表面改性。利用XRD、SEM、TEM、HRTEM、XPS、UV-Vis DRS、PL对样品进行了表征和分析，考察了其在可见光下降解亚甲基蓝的光催化性能。结果表明，当水热温度为120 ℃时，WO3/Bi2WO6纳米片具有较好的光催化性能；TiO2/WO3/Bi2WO6复合催化剂中掺入TiO2质量分数为10.7%时，所得三元复合材料的光催化性能远优于WO3/Bi2WO6纳米片；经等离子体改性处理后，三元复合材料的吸收边向可见光红移，放电输入功率的增加有助于提高复合材料的光催化活性，当放电电压为1.1 kV时，复合材料的降解速率常数分别是未处理样品和WO3/Bi2WO6的2.2倍和3.9倍。     

光还原法制备增强光催化性能的Bi-TiO_2纳米管

采用阳极氧化法及简易光沉积法制备了一种Bi-TiO_2纳米管(Bi-TNAs)光催化剂,并对其形貌、晶相以及光吸收性能进行表征。结果显示,薄片状的金属相Bi微米片成功沉积在TiO_2纳米管阵列表面。光催化降解罗丹明B实验显示,Bi-TNAs的光催化降解性能比TNAs显著增强。单质Bi微米片作为电子陷阱可捕获TiO_2的光生电子,延长载流子寿命,降低电子-空穴复合速率,增强TNAs光催化降解罗丹明B的活性。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。