纳米硫化铜的制备及光催化性能

本文以铜盐(如CuCl_2、CuSO_4、Cu(NO_3)_2)和ZnS为原料,在100℃、水溶液条件下成功制备了纳米CuS。产品用XRD、SEM和UV-Vis进行表征。以甲基橙为降解物,测定了Cu S产品的光催化活性。结果表明,在氙灯的照射下,纳米CuS产品的光催化效率分别为17.17%,44.30%和45.23%。     

CuS纳米材料的水热法制备及其光催化性质研究

以氯化铜和硫代乙酰胺为原料,聚乙二醇400(PEG400)为表面活性剂,采用水热法在160℃下反应10h成功制备了CuS纳米管和CuS纳米颗粒。用X射线粉末衍射仪(XRD)、扫描电子显微镜(SEM)、N_2吸脱附和荧光光谱仪(PL)多种手段对产品进行表征。以罗丹明B、甲基橙为目标降解物,考察了CuS纳米管和纳米颗粒的光催化活性。结果表明:所制备的产品为六方相CuS;PEG400对产品的形貌有很大影响;CuS纳米管在紫外光照射140min后对罗丹明B和甲基橙的降解率达到81.5%和87.9%,CuS纳米颗粒对罗丹明B和甲基橙的降解率约为63.5%和66.6%。CuS纳米管的光催化活性明显优于CuS纳米颗粒。     

N、La共掺杂纳米TiO_2的制备及其光催化性能

以钛酸丁酯、尿素、硝酸镧为原料,采用超声辅助溶胶-凝胶法制备了N、La共掺杂纳米TiO_2光催化材料。用XRD、DSC-TG、UV-Vis DRS、FT-IR、SEM、EDS对材料结构和性能进行了表征。以苯酚为目标污染物,考察材料的光催化性能。结果表明:N、La共掺杂协同作用使晶粒细化,材料的光催化活性显著提高;当N掺杂摩尔分数为5%、La掺杂摩尔分数为1%、催化剂用量为1.5 g/L、焙烧温度为500℃时,光催化降解5 mg/L苯酚的效果最佳。     

γ-Fe_2O_3/BiOI光催化材料的制备及其性能研究

利用水热法合成了新型磁性γ-Fe_2O_3/BiOI纳米复合材料,并用X射线衍射(XRD)、扫描电子显微镜(SEM)、紫外可见漫反射(UV-Vis DRS)、能谱元素分析(EDS)、磁性表征(VSM)对其结构进行表征。通过在可见光下降解亚甲基蓝(MB),对其光催化性能进行评价,结果表明,5%γ-Fe_2O_3/BiOI磁性复合材料的光催化活性较好,60 min对MB的降解率达到97%。可在外加磁场的作用下实现快速分离与回收。光催化剂的回收循环实验表明,3次循环利用后对MB的光催化降解率仅小幅下降,说明其具有很好的重复稳定性。     

花状硫化铜的制备及其光催化性能研究

采用氯化铜和硫脲为原料,1,2-丙二醇为溶剂,通过溶剂热法在170℃反应5 h制备了具有紫外/可见光催化活性的花状硫化铜。采用XRD、SEM、FTIR、TG以及UV-Vis等手段对产品进行了表征,结果表明,制备的产品是六角相的CuS,在紫外/可见光区有强烈的吸收,禁带宽度Eg=1.45 e V,比表面积15.8 m~2/g。并以氙灯和汞灯为光源,亚甲基蓝为目标降解物评价了CuS微球的光催化活性。光催化结果表明,在汞灯下光照15,30 min,亚甲基蓝的降解率为69.46%,98.26%;在氙灯下光照15,30 min亚甲基蓝的降解率为89.27%,100%。此外,还分析了硫化铜微米球超结构形成机理。     

微乳液-水热法制备纳米氢氧化钙及其对亚甲基蓝去除的研究

通过微乳液-水热法合成纳米级氢氧化钙,利用XRD、SEM、UV-Vis DRS、PL等对样品进行表征;考察其在可见光下对亚甲基蓝降解能力及其光催化性能。结果表明,当光强度为300 W时,5 min降解效率可达98.9%;氢氧化钙自身呈碱性的特性对亚甲基蓝降解有促进作用;光催化降解亚甲基蓝为间接染料光敏化作用,其中起主要作用的是羟基自由基,超氧自由基也有参与。氢氧化钙降解亚甲基蓝不仅有光催化作用,还发生均相离子反应使其降解为小分子物质。     

BiVO_4-MnO_2光催化剂的制备及性能

采用一步水热法制备了BiVO_4-MnO_2复合材料,通过XRD、FTIR、SEM、EDS、XPS、PL和UV-Vis DRS对其结构进行了表征,并以罗丹明B溶液作为目标降解物考察了其光催化活性。结果表明:BiVO_4复合MnO_2构成了较大的孔径和比表面积,有利于分子尺寸为1.59 nm×1.18 nm×0.56 nm的罗丹明B分子扩散和吸附;BiVO_4与MnO_2二者之间产生了电子耦合作用,减弱了BiVO_4的荧光强度,表明复合MnO_2能有效地抑制光生电子和空穴的复合,提高量子的利用效率,使得复合材料较单独的BiVO_4或MnO_2对罗丹明B(Rh B)有较好的光催化降解效果。当m(MnO_2)∶m(BiVO4)=10∶100时,光照3 h对10 mg/L的Rh B(100 mL)的降解率达到97.8%。     

TiO_2/ZnO纳米多孔复合膜制备及光催化性能研究

分别采用水热处理和添加有机物的方法制备了TiO2/ZnO纳米多孔复合膜,利用XRD、SEM、TEM和EDS对薄膜进行了分析表征,通过甲基橙降解研究了多孔膜的光催化性能。结果表明:采用这两种方法都可获得具有孔洞特征的多孔复合膜,对添加有机物法制备的多孔膜进行的光催化降解实验表明该多孔膜光催化性能明显优于致密复合膜。     

AgI-BiOCl复合材料的制备及其光催化性能研究

通过原位沉积法制备了直接Z型光催化剂AgI-BiOCl。通过XRD、SEM、XPS、FTIR、UV-Vis DRS和荧光光谱(PL)等技术对复合材料的形貌、结构和吸光性能进行表征。以盐酸四环素为目标降解物,AgI-BiOCl复合材料表现出比BiOCl和AgI更突出的光催化降解活性。其中,AgI-BiOCl-10的降解速率分别是BiOCl和AgI的4.74和2.52倍。自由基捕获实验表明,·O^-_2是光催化降解过程中的主要活性物种。基于自由基捕获实验及两种半导体的能带结构分析,探讨了合理的载流子转移机制及降解机理。     

BiOCl/Bi_2WO_6复合材料的制备及其光催化性能研究

通过水热-溶剂热法制备了BiOCl/Bi_2WO_6复合材料。采用XRD、SEM、UV-Vis DRS等测试手段对复合光催化剂的结构、形貌和光学性质进行表征。通过光催化降解罗丹明B溶液对其光催化性能进行评价。结果表明:与纯Bi2WO6样品相比,BiOCl/Bi_2WO_6样品对罗丹明B的光催化降解能力显著增强,且复合光催化剂具有较高的稳定性,重复使用4次后,罗丹明B的降解率变化不明显,仍可达到97.8%。     

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。