玻璃纤维负载纳米TiO2的制备及光催化性能

采用浸渍-提拉法在玻璃纤维(GF)表面负载纳米TiO2,制备TiO2/GF复合光催化剂.通过X射线衍射(XRD)、热重-差热分析(TG-DSC)、扫描电镜(SEM)及能谱元素分析(EDS)对TiO2/GF复合光催化剂的结构进行了表征.结果表明,经550 ℃以下热处理,TiO2的晶型为锐钛矿相,随着热处理温度的升高,TiO2的晶型逐渐转化为金红石相.以亚甲基蓝的光催化降解为探针反应,评价TiO2/GF复合材料的光催化活性.复合材料的光催化降解活性与P25相当,且经多次使用后,复合光催化剂对亚甲基蓝的降解率仍保持在80%以上.     

Ce3+掺杂TiO2光催化性能研究

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.     

纳米二氧化钛纤维的制备及其光催化活性

以钛酸丁酯为钛源,用溶胶-乳化-凝胶技术合成了纳米TiO2粉末,将其置入碱溶液中进行回流处理得到了纳米TiO2纤维.用X射线衍射和透射电镜对纳米TiO2的晶型和表面形貌进行表征.结果表明:当氢氧化钠溶液的浓度为10 mol/L时,所制备的纳米TiO2纤维直径为10～15 nm,纤维长径比为20～25.TiO2纤维在750℃热处理后发生由锐钛矿相向金红石相的转变.光催化降解亚甲基蓝的实验显示:未经热处理的TiO2纤维的光催化活性比纳米TiO2粉末的差,而经500℃热处理后的TiO2纤维光催化活性最强,在紫外光照射4 h后,亚甲基蓝降解率达92%.当热处理温度进-步升高后,TiO2纤维光催化活性反而降低.     

热处理温度对TiO2-x/Al2O3复合材料的光催化性能影响研究

以钛酸铝(Al2TiO5)为原料,在碳粉埋烧条件下,利用原位固相热分解法制备了TiO2-x/Al2O3异质结构复合光催化剂.研究了不同热处理温度对TiO2-x/Al2O3样品的物相结构、微观形貌和紫外可见光吸收性能的影响规律.并通过对亚甲基蓝(MB)染料的降解率来表征样品的光催化性能.实验结果表明,热处理温度为1100...     

高炉渣纤维负载TiO2光催化材料的制备及其光催化性能

以高炉渣纤维(BFSF)为载体,采用溶胶凝胶法,在BFSF表面负载TiO2,制备BFSF负载TiO2(TiO2/BFSF)光催化材料.利用差热-热重(TG-DTA)、X射线衍射仪(XRD)、场发射扫描电镜(SEM)及能谱元素分析(EDS)等近代测试方法对TiO2/BFSF的显微结构和相组成进行了表征.以模拟印染废水的亚甲基蓝(MB)的降解,评价样品的光催化活性.实验结果表明:TiO2溶胶负载3次,煅烧温度为450℃时,TiO2/BFSF光催化材料表面负载了一层均匀密实的锐钛矿型TiO2,当紫外光照射180 min时,亚甲基蓝的降解率达到92.5％.循环利用TiO2/BFSF光催化材料4次,亚甲基蓝的降解率依然能够达到63％.     

CoO/CdS纳米复合材料的制备及其光催化降解亚甲基蓝的研究

采用物理气相沉积法制备CoO/CdS纳米复合材料,通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线能谱仪(E DS)和紫外-可见分光光度计(UV-Vis)对其形貌、结构和光吸收性质进行表征,并以亚甲基蓝溶液的光催化降解为探针反应,在可见光下考察CoO/CdS纳米复合材料的光催化性能.结果表明,CoO/CdS纳米复合材料的光催化活性显著高于CdS纳米颗粒,100 min后亚甲基蓝降解率达到92.4％.     

氮掺杂制备锐钛矿型纳米TiO2及降解甲基橙的研究

采用溶胶凝胶法制备了氮掺杂TiO2光催化剂。考察了氮的掺杂量、热处理温度对TiO2光催化能力的影响。用XRD、 SEM和紫外-可见光分度计对样品的晶型、形貌和光催化性能进行表征。结果表明氮的掺杂有助于改善TiO2的光催化性能,在灯光照射下5％N-TiO2煅烧温度为450℃时表现出较高的光催化活性和降解甲基橙溶液的能力,在80 min内降解甲基橙溶液达到了98％。     

钕和镨共掺杂TiO2光催化性能的研究

采用溶胶—凝胶法制备纯纳米TiO2、钕和镨掺杂的纳米TiO2光催化剂,以甲基橙为目标降解物,研究了催化剂加入量、染料初始质量浓度、溶液pH值对甲基橙降解率的影响.实验结果表明,钕掺杂的纳米TiO2光催化活性高于纯纳米TiO2的光催化活性,而适量钕镨共掺杂纳米TiO2光催化活性可进一步提高,最佳掺杂浓度为0.5％的钕和0.2％的镨.当钕和镨共掺杂纳米TiO2催化剂加入量为2.0g/L,甲基橙溶液的初始质量浓度为30 mg/L,pH值为10.5时,在40 W紫外灯光照射35 min后降解率最好,可达到93％.     

界面聚合制备TiO2-PANI纳米材料的光催化性能研究

本文以染料亚甲基蓝(MB)为目标降解物,探讨了界面聚合法制备的TiO2-PANI共轭高分子纳米复合材料在钠光下的光催化性能。结果表明:TiO2-PANI复合材料降解MB溶液在110 min时,溶液中MB的浓度从15 mg.L-1为减小为0.847 mg.L-1,大大降低了水中亚甲基蓝的含量。     

N/F/TiO2的制备及光催化氧化性能

以钛酸四丁酯为钛源,以尿素和氟化铵为N、F源,制备N/F/TiO2光催化材料,用于亚甲基蓝降解效率研究.结果表明,摩尔比为N∶F∶Ti=1∶4∶5的光催化剂在锻烧温度为600℃、pH =7的条件下,100 mg N/F/TiO2光催化剂对100 mL浓度为20 mg/L的亚甲基蓝溶液光催化降解4h时效率最高.     

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。