前驱体对熔盐法合成Bi2WO6光催化剂及其性能的影响

分别以Bi(NO3)3和Na2WO4溶液直接混合所得沉淀、加氨水所得沉淀及Bi(NO3)3×5H2O+Na2WO4×2H2O为前驱体,采用熔盐法合成Bi2WO6光催化剂粉体,研究了不同前驱体所制粉体的物相、形貌,以其为催化剂,在可见光照射下降解罗丹明B溶液. 结果表明,用后二者为前驱体均可得到薄片状纯相Bi2WO6粉体. 加氨水所得沉淀为前驱体所制Bi2WO6粉体的光催化性能最好,在可见光照射下对0.01 mmol/L RhB溶液的降解率在60 min内达99%.     

花状钨酸铋纳米粉体的制备及其光催化性能研究

文章以Na2WO4·2H2O和Bi(NO3)3·5H2O为原料,采用简单水热合成法制备了具有三维花瓣状结构的Bi2WO6光催化剂,并利用SEM和XRD等方法对光催化剂的形貌和结构进行了表征。考察了反应时间、Bi2WO6加入量、染料罗丹明B的初始浓度和光强对罗丹明B光催化降解效果的影响。实验结果表明,160℃下24 h水热合成的Bi2WO6光催化剂,以氙灯(不加滤光片)为光源,在500 W下光照60 min,对浓度为4.79 mg/L的罗丹明B溶液的去除率最高可达94.6%。由此可见水热合成的花瓣状Bi2WO6具有较高的光催化活性,在光催化降解染料废水方面具有潜在的应用价值。     

Bi2WO6在多孔Al2O3纤维上的原位生长及其光催化性能表征

以多孔Al2O3纤维为载体,应用水热方法使Bi2WO6在纤维上原位生长.利用XRD、SEM等分析测试手段对样品进行表征,研究了在水热温度为180℃条件下,不同水热保温时间和pH值对纤维上Bi2WO6形成及结晶形貌的影响.分析评价了负载有Bi2WO6的多孔Al2O3纤维在可见光辐照下对RhB溶液的光催化降解性能.结果表明,Bi2WO6微晶不仅能够在比表面较大的多孔Al2O3纤维上原位生长,且致密均匀,并具有良好的针状结晶形貌.不同的水热保温时间和pH值对应生成的Bi2WO6结晶形貌以及光催化性能也呈现一定的规律,在保温时间为9h,pH=1的条件下,Bi2WO6生长的最为致密均匀,且保持多孔结构,在60 min内可使RhB降解95％.     

超大Bi2WO6微球的水热合成及光催化性能研究

以硝酸铋、钨酸钠为原料,采用水热法合成了超大Bi2WO6微球,并使用X射线衍射、场发射扫描电子显微镜、透射电子显微镜、紫外可见分光光度仪等手段对样品进行表征,考察了其可见光催化降解RhB的性能。结果表明,水热反应生成了结晶度较高的且具有大量孔结构的超大微球,样品的吸收阈值位于可见光范围内,禁带宽度为2.71eV。样品经可见光照60min,RhB的降解率达到93.2%,循环使用6次后,光催化性能未出现大幅减弱。     

低温固相反应合成Bi2WO6粉体及其可见光光催化性能

以Bi(NO3)3?5H2O和Na2WO4?2H2O为原料,采用固相法直接合成Bi2WO6粉体,研究了反应温度和保温时间对产物物相、形貌及可见光光催化性能的影响. 结果表明,350℃下保温2 h所得粉体含少量Bi2O3和Na2W4O13杂质,但光催化性能最好,可见光照射90 min对0.01 mmol/L RhB溶液的降解率达95%,且经5次循环后光催化活性和化学稳定性良好.     

pH值对Bi2WO6粉体的微波水热法合成及光催化性能的影响

以Na2WO4·2H2O和Bi(NO3)3·5H2O为原料,采用微波水热法通过调节pH值在200℃合成出花簇状和片状Bi2WO6粉体.利用X射线衍射、场发射扫描电子显微镜、透射电子显微镜、选区电子衍射和高分辨透射电子显微镜等对Bi2WO6粉体进行了表征,并对合成粉体的光催化性能进行了研究.结果表明:pH值对Bi2WO6...     

Bi2WO6的静电纺丝法制备及其光催化性能

以聚乙烯吡咯烷酮(PVP)、钨酸铵[(NH4)10W12O41]和柠檬酸铋铵(C6H13BiN2O7.H2O)为原料,利用静电纺丝技术成功制备了PVP/C6H13BiN2O7.H2O-(NH4)10W12O41(简写为PVP/BiWO)前躯体,对PVP/BiWO缓慢控温处理制得Bi2WO6。采用差热-热重分析(TG-DTA)、X射线粉末衍射(XRD)、傅里叶红外光谱(FTIR)、X-射线光电子能谱(XPS)、场发射扫描电镜(FE-SEM)、紫外可见漫反射(UV-Vis-NIR/DR)等分析手段研究热处理温度对材料结构的影响,通过罗丹明B(RhB)光降解反应研究其光催化性能。结果表明,可见光照射下,热处理温度600℃时材料的光催化活性最好,并探讨了其光催化机理。     

Bi2Sn2O7粉体微波水热法制备及其吸附-可见光催化性能研究

以物质的量比为1∶1的Bi(NO3)3.5H2O和Na2SnO3.3H2O为原料,采用微波水热法合成Bi2Sn2O7粉体。采用XRD、SEM对粉体的晶相和形貌进行了表征,并以甲基橙为目标污染物,测试粉体的光催化性能。研究了合成时间、合成温度等因素对样品催化性能的影响,同时以KI、NBT及乙腈作为抑制剂,检测光催化过程产生的活性物质。结果表明:200℃、30 min微波水热合成的2 g/L Bi2Sn2O7粉体在暗光条件下搅拌2 h,对20 mg/L甲基橙溶液的吸附率为40%,将其置于250 W的卤素灯下光照2 h,甲基橙溶液的脱色率达95%以上。活性物种的检测表明光催化过程产生的主要活性物种为·OH和·O2-。     

纳米花瓣状Co_3O_4/NiO的制备及其光催化性能研究

以氯化钴、氯化镍和六次亚甲基四胺为原料,通过水热反应合成Co_3O_4/NiO前驱体材料,经过煅烧得到Co_3O_4/NiO样品。研究不同煅烧温度对样品形貌的影响,并采用X射线衍射仪(XRD)和场发射扫描电子显微镜(FESEM)检测样品的结构和形貌,结果表明:在400℃煅烧后,得到纳米花瓣状结构Co_3O_4/NiO,花瓣厚度为50nm,表面有多孔结构。对比纳米花瓣状Co_3O_4/NiO、Co_3O_4、NiO和无催化剂条件下对吡啰红B(PB)的紫外光降解效率,纳米花瓣状Co_3O_4/NiO表现了最好的光催化活性,在180 min后对PB的降解率达95%。     

WO_3/BiOBr复合催化剂的制备及可见光催化降解甲基橙

以Bi(NO_3)5·5H_2O、Na Br、H_2WO_4为原料,采用一步水热合成法合成不同n(W)∶n(Br)的WO_3/BiOBr复合催化剂,并通过SEM和TEM对催化剂进行表征分析。以甲基橙为探针污染物,考察前驱液pH、水热温度、水热时间和n(W)∶n(Br)对WO_3/BiOBr复合催化剂活性的影响。结果表明,在pH为10.2、100℃水热时间6 h合成n(W)∶n(Br)为0.02的WO_3/BiOBr复合催化剂活性最好,光照120 min后,对目标污染物的降解率达99.39%,较BiOBr催化剂(合成条件为原始pH值,100℃水热反应6 h)提高了30.85%。采用水热合成法制备的WO_3/BiOBr复合催化剂具有良好的可见光活性。     

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.     

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.     

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。     

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.     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Some Large Wood-Boring Beetles in Southeastern USA

Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.