纳米ZnO的水热合成及性能研究

采用简单的水热方法制备出纯净且粒径均匀的纳米Zn O粒子,借助于X射线粉末衍射仪(XRD)和扫描电子显微镜(SEM)对其物相组成及表面形貌进行了表征,通过日光下亚甲基蓝的降解研究了其光催化性能。将获得的ZnO纳米粒子沉积成膜,经表面修饰低表面能物质1H,1H,2H,2H-全氟辛基三氯硅烷(CAS)后,采用接触角测量仪研究了其润湿性能。结果表明,反应时间为20 h的ZnO纳米粒子在日光照射20 min后,亚甲基蓝的降解率达到90%以上;经表面修饰CAS后,Zn O膜呈现良好的疏水性能;经紫外光照射后,疏水性ZnO膜转换为亲水性,实现了润湿性的转换。     

稀土掺杂对ZnO材料结构及光催化性能的影响研究

为提高ZnO光催化性能采用超声波辅助微波水热法分别制备了ZnO、Nd/ZnO及Dy/ZnO光催化材料,利用XRD、SEM、FESEM、XPS及亚甲基蓝降解实验对样品的结构与性能进行了表征.研究表明:掺杂Nd及Dy有助于促进六方纤锌矿结构ZnO晶体的生长.与纯ZnO相比,掺杂Nd及Dy促进了样品表面羟基化及氧的吸附,从而提高了ZnO的光催化活性.采用超声波辅助微波水热法制备的样品光催化性能优异,紫外光辐照4h后,ZnO、Nd/ZnO、Dy/ZnO样品对亚甲基蓝的降解率分别为89.69％,91.01％,91.13％.     

单壁碳纳米管显著增强的ZnO可见光催化活性

利用醋酸锌为原料,采用溶胶-凝胶法制备了单壁碳纳米管(SWMTs)和氧化锌的纳米复合物(ZnO/SWNTs)。用X射线衍射光谱(XRD)、拉曼光谱、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、热重分析(TGA)、傅里叶变换红外光谱(FT-IR)以及紫外-可见吸收光谱(UV-Vis)对复合物进行了表征。结果显示,粒径为10~20 nm的ZnO粒子均匀地负载在SWNTs表面,且在可见光区具有很好的光吸收性能。研究了ZnO/SWNTs光催化剂在太阳光照射下对甲基橙和亚甲基蓝的光催化降解情况。结果表明,复合物的催化活性明显高于ZnO。对于甲基橙,光照200 min后,降解率为99.8%,是纯ZnO(4.8%)的20倍;对于亚甲基蓝,仅光照20 min,降解率就达到了98.4%,是纯ZnO(4.0%)的25倍。     

溶剂热法制备Ag/ZnO纳米复合材料及其光催化性能的研究

用溶剂热法制备了Ag/ZnO纳米复合材料,用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、能量色散谱点(EDS)分析了复合材料的表面形貌及结构.以亚甲基蓝为模拟污染物,在紫外光照射下考察了纳米Ag/ZnO复合材料的光催化活性.结果表明,一定量银沉积能有效地改善ZnO时亚甲基蓝的光催化降解性能.     

ZnO/氧化石墨烯复合材料的制备及其可见光催化性能

以均匀沉淀法制备纳米ZnO,并将其负载在氧化石墨烯(GO)上制得了ZnO/GO复合材料。XRD、TEM、UV、PL等证实在GO表面分散着颗粒均匀的ZnO纳米颗粒,GO与ZnO纳米颗粒之间存在电子转移效应,抑制ZnO中光生电子空穴对的复合,提高了ZnO的可见光催化性能;考察了复合材料在模拟太阳光条件下降解亚甲基蓝的光催化性能,当GO添加量为10%时,模拟太阳光照射90 min后,对亚甲基蓝的降解率达到97.2%,经过10次循环使用后降解率没有明显降低,复合材料的可见光催化活性明显优于纯的纳米ZnO,同时ZnO/GO复合材料对部分工业染料也有很好的降解活性。     

ZnO/氧化石墨烯复合材料的制备及其可见光催化性能?

以均匀沉淀法制备纳米ZnO,并将其负载在氧化石墨烯(GO)上制得了ZnO/GO复合材料。XRD、TEM、UV、PL等证实在GO表面分散着颗粒均匀的ZnO纳米颗粒,GO与ZnO纳米颗粒之间存在电子转移效应,抑制ZnO中光生电子空穴对的复合,提高了ZnO的可见光催化性能;考察了复合材料在模拟太阳光条件下降解亚甲基蓝的光催化性能,当GO添加量为10%时,模拟太阳光照射90 min后,对亚甲基蓝的降解率达到97.2%,经过10次循环使用后降解率没有明显降低,复合材料的可见光催化活性明显优于纯的纳米ZnO,同时ZnO/GO复合材料对部分工业染料也有很好的降解活性。     

单壁碳纳米管显著增强的ZnO可见光催化活性

利用醋酸锌为原料,采用溶胶-凝胶法制备了单壁碳纳米管（SWMTs）和氧化锌的纳米复合物（ZnO/SWNTs）。用X射线衍射光谱（XRD）、拉曼光谱、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、热重分析（TGA）、傅里叶变换红外光谱（FT-IR）以及紫外-可见吸收光谱（UV-Vis）对复合物进行了表征。结果显示,粒径为10～20 nm的ZnO粒子均匀地负载在SWNTs表面,且在可见光区具有很好的光吸收性能。研究了ZnO/SWNTs光催化剂在太阳光照射下对甲基橙和亚甲基蓝的光催化降解情况。结果表明,复合物的催化活性明显高于ZnO。对于甲基橙,光照200 min后,降解率为99.8%,是纯ZnO（4.8%）的20倍;对于亚甲基蓝,仅光照20 min,降解率就达到了98.4%,是纯ZnO（4.0%）的25倍。     

铁掺杂氧化锌纳米晶的制备及光催化性能研究

通过水热法制备了铁掺杂氧化锌纳米晶,采用红外、X射线衍射（XRD）、可见光谱对其进行了表征,并以铁掺杂纳米氧化锌对亚甲基蓝进行催化降解实验来检验其催化降解性能,结果表明当Fe^＋／ZnO纳米晶浓度为1．0mol／L、亚甲基蓝质量浓度为5mg／L、太阳光照射3h时,甲基橙降解效果最好,降解率达90％以上。     

纳米ZnO/膨润土光催化降解亚甲基蓝研究

以Zn(NO3)2和膨润土为原料,采用沉淀法制备纳米ZnO-膨润土复合光催化材料,用FT-IR、XRD和SEM对其结构和形貌进行了表征。以高压汞灯为光源,光催化降解活性亚甲基蓝模拟染料废水,研究了ZnO/有机膨润土光催化降解性能,讨论了影响亚甲基蓝降解率主要因素。结果表明,在光照射下1.5 h,ZnO/膨润土光催化降解亚甲基蓝达96%,其重复使用降解效果保持稳定,利用该复合光催化材料降解有机染料废水是一种可行的方法。     

纳米氧化锌和纳米银对棉织物的多功能整理

以植物金银花提取物作为还原剂制备了纳米ZnO和纳米Ag,通过浸轧法将纳米ZnO单独整理以及将两者依次整理到棉织物上制备多功能棉织物(ZnO-棉织物、ZnO/Ag-棉织物).利用SEM、XRD、FTIR分析了整理前后棉织物的形貌和结构,并探讨了整理后棉织物的多功能性.结果表明,棉织物上的纳米粒子分布较均匀且发生了轻微团聚.与ZnO-棉织物相比,ZnO/Ag-棉织物对亚甲基蓝(MB)和红酒的降解率分别提高了7.09％和10.61％,说明纳米Ag提升了纳米ZnO的光催化活性.ZnO-棉织物经过10次洗涤后其纳米粒子含量虽有小幅下降,但对MB的降解率仍达到83.24％以上,说明负载纳米粒子后棉织物具有良好的自清洁能力和耐洗性能.此外,ZnO-棉织物和ZnO/Ag-棉织物的紫外防护系数(UPF)值分别达到33.23和41.06,对大肠杆菌和金黄色葡萄球菌的抑菌率均达到95％以上,表现出优良的抗紫外线性和抗菌性能.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。