二氧化钛光催化降解硝基苯废水

用紫外灯作为光源,以锐钛型TiO2为催化剂降解硝基苯。探讨了光照时间、初始pH值、初始浓度、催化剂用量和载铜TiO2复合催化剂对光催化降解的影响。结果表明,TiO2用量为3.0 g/L,pH为3,硝基苯初始浓度为40.6 mg/L,室温条件下,光照6 h硝基苯降解率为80.6%;掺杂1%Cu2+(摩尔分数)的TiO2复合催化剂,光催化活性高于纯TiO2,其光催化降解率较TiO2提高14.5%。     

铁掺杂二氧化钛光催化降解硝基苯的动力学研究

采用水热法制备了锐钛矿型铁掺杂TiO2光催化剂,以分析初始浓度、催化剂用量、TiO2的掺铁量、溶液的pH值对光催化速率的影响为基础,研究了铁掺杂二氧化钛催化硝基苯动力学行为.结果表明:可见光照射下,硝基苯溶液初始浓度为50 mg/L、TiO2掺铁量为0.05％(物质的量分数)、催化剂用量为1.2 g/L,溶液pH为3、室温下光照反应2.5h,硝基苯的降解率和反应速率常数k达到最大值.光催化反应符合Langmuir-Hinshelwood动力学规律,硝基苯的降解过程表现为一级反应,k为0.0028 min-1.     

Y3+掺杂TiO2纳米棒的制备及光催化降解硝基苯

本文以乙二胺作添加剂,采用溶胶-凝胶法制备了Y3+掺杂的纳米TiO2粉体.透射电镜TEM)分析结果表明,所制备的TiO2粉体具有纳米棒状结构,平均颗粒直径为15nm左右,长度为150～250nm左右.光催化降解硝基苯的实验结果说明,与盐酸作添加剂制备的TiO2粉体相比,乙二胺法制备的掺Y3+TiO2粉体具有更高的光催化降解性能.     

TiO2溶胶／UV催化降解直接大红4BS

以钛酸正丁酯为前驱体、乙醇为溶剂、盐酸为催化剂,采用溶胶法制备了具有光催化性能的TiO2溶胶.研究了染料初始浓度、pH、H2O2添加量对直接大红4BS降解效果的影响,同时考察了TiO2溶胶/UV体系与TiO2溶胶,H2O2/UV体系光催化的反应动力学.结果表明,当直接大红4BS的初始浓度为0.2 g·L-1、pH为2.0时,TiO2溶胶对直接大红4Bs的降解效果较好;当H2O2添加浓度为0.03%时,可以有效促进光催化反应,当添加浓度增大时,对光催化反应没有促进作用.TiO2溶胶光催化反应符合一级反应,半衰期为81.1;TiO2溶胶/H2O2体系光催化反应半衰期为72.6,TiO2溶胶/H2O2体系具有更优的光催化效率.     

超声波降解罗丹明B的研究

报道了用超声波诱导降解模拟水中低浓度罗丹明B染料废水的可行性实验.实验探讨了频率、功率、初始pH、O2、S2O2-8、TiO2光催化对降解速度的影响.实验结果表明:在功率为100%,频率为59 kHz,低pH,充O2饱和条件下,罗丹明B去除效果较好,在紫外光存在下加入S2O28能加快罗丹明B的降解,在TiO2光催化协同作用下,连续反应100 min,2.5 mg/L的罗丹明B 溶液去除率达88.37%.     

TiO_2光催化降解林可霉素废水的研究

以250W紫外灯作光源,以TiO2为催化剂,研究了林可霉素光催化降解的合适条件.结果表明,在TiO2用量为0.4 g/L,pH为5.0,林可霉素初始质量浓度为60 mg/L,光催化反应90 min的条件下,林可霉素降解率达到100%.掺杂1%(以物质的量计)Cu2+的TiO2复合催化剂,其光催化活性高于纯TiO2.将优化的光催化降解体系用于林可霉素生产厂废水的处理,可实现林可霉素的完全去除.     

光催化降解含萘污水

在Pt/TiO2存在下,研究了光催化降解水中污染物萘的反应,结果表明,萘能被有效光催化降解,反应60 min时,降解百分率可达40%;萘的最佳处理酸度为pH=3.0;萘初始浓度对光催化反应速率的影响符合Langmuir-Hinshelwood关系式。     

光催化技术降解MDI高含盐废水中氯苯的研究

以紫外灯为光源,在圆柱型光化学反应器中,TiO2为催化剂,研究了光催化技术对MDI高含盐废水中氯苯的降解;探讨了催化剂的投加量、pH及氯苯的浓度对光催化反应的影响,并对实验现象予以解释。     

ZnO掺杂TiO2光催化降解含铬废水的研究

采用溶胶-凝胶法制备ZnO-TiO2复合半导体光催化剂和纯TiO2光催化剂。以含铬废水为降解目标物,研究了ZnO掺杂TiO2为催化剂的紫外光催化反应,来探讨ZnO掺杂对TiO2光催化降解含铬废水的可行性。并重点考察了ZnO的掺杂量、催化剂的添加量、溶液初始浓度、光照时间、溶液pH值对降解效率的影响。实验结果表明:当ZnO掺杂比为2.0%、催化剂用量为0.8g/L、pH为4、浓度为2.0mg/L的含铬废水250 mL,30瓦紫外灯光照降解15 min时,含铬废水降解率可达96.2%。     

含钛矿渣的表征及在超声波作用下催化降解含硝基苯废水

以含钛矿渣为催化剂,在超声波作用下对硝基苯废水进行了催化降解研究.实验结果表明:钛精矿、高钛渣、攀钢渣、承钢渣4种催化剂颗粒外观相似,具有较小的比表面积(3.0～8.17 m2/g)和孔容(0.0016-0.0051 mL/g),且与水的润湿性较好.钛精矿中的钛主要以锐钛型和金红石型TiO2存在,高钛渣中的钛以主要以金红石型TiO2存在,攀钢渣、承钢渣主要含有CaTiO3,在自然光条件下,对硝基苯的降解没有光催化活性.在45 kHz超声作用下,催化剂对硝基苯的降解均显示出催化活性.相同实验条件下,催化性能与矿渣中的钛含量有关,钛含量越高,催化活性越好.     

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。