模板法组装Ag纳米线阵列及其微结构

以多孔阳极氧化铝(AAO)作为模板,利用直流电沉积法,在AAO模板孔洞中成功组装了Ag纳米线阵列。扫描电子显微镜(SEM)分析表明,Ag纳米线的长度分布十分均匀,其长度随着沉积时间的延长而线性增长,生长速度约为5μm/h。透射电子显微镜(TEM)表明,Ag纳米线粗细均匀,直径约为200 nm。选区电子衍射(SAED)分析表明,所得Ag纳米线具有多晶结构。     

氧化铝模板中Ag纳米线阵列的选择性生长

利用Ag离子与Br离子之间的化学沉积作用在孔隙中充满明胶的阳极氧化铝（AAO）模板中制备了AgBr/AAO纳米介孔复合材料.材料选择性曝光后,利用原位显影液对其进行化学显影,在AAO模板中选择性得到Ag纳米线阵列.实验结果表明：Ag纳米线是连续的、致密的,且具有多晶结构,充满了曝光部分的模板孔隙.本文还对影响Ag纳米线选择性生长的因素进行了简单讨论.     

以多孔氧化铝为模板钴纳米线阵列的制备

以多孔氧化铝为模板,采用交流电沉积的方法制备了钴纳米线阵列膜.采用扫描电子显微镜(SEM)对电沉积钴纳米线前后的多孔氧化铝模板的形貌进行表征,通过透射电子显微镜(TElM)观察钴纳米线的表面形貌.结果表明:金属钴沉积到多孑L氧化铝模板的纳米孑L中,钴纳米线的平均直径约为50n/n,与氧化铝模板的孔径相一致.     

Cu@ZnO/Ag花簇型三元异质结构纳米复合材料的合成及其光催化性能的研究

采用模板化法制备了具有花簇形态的三元异质结构纳米复合光催化剂Cu@ZnO/Ag。首先,采用水热法制备Cu纳米线并将其作为核心,然后使ZnO纳米棒在核心表面生长,得到Cu纳米线-ZnO纳米棒(Cu@ZnO)复合物。最后,通过光沉积法将Ag纳米粒子(Ag NPs)负载在ZnO纳米棒上。通过扫描电子显微镜(SEM)、高分辨率透射电子显微镜(HRTEM)、能量色散谱仪(EDS)和X射线衍射(XRD)研究和确认了样品的形态和微观结构。光催化活性研究表明,Cu@ZnO/Ag在模拟太阳光照射下对RhB水溶液的降解具有较高的活性,当Ag NPs的负载量为5%(wt),且RhB的浓度为1×10-5 mol/L时,样品的催化活性达到最佳。     

Ag2O-钛酸锶钡的制备及内建电场调控可见光催化性能研究

采用水热法结合共沉淀法制备Ag2O-钛酸锶钡(Ag2O-BST)纳米线复合材料,将罗丹明B作为模拟污染物,研究Ag2O-BST的可见光催化活性。结果表明:水热合成温度影响BST纳米线成分和形貌,温度为85℃时剩余H2Ti3O7模板含量最低,立方体晶粒较少。Ag2O相对含量低的Ag2O-BST在光照后期降解效率较纯Ag2O高14%,Ag2O-BST复合材料中BST自发极化产生的内建电场有助于促进界面处光生电子-空穴对的分离,提升可见光催化性能。     

氧化镍纳米线的制备及光电性能研究

通过电沉积法在阳极氧化铝(AAO)模板内制备了镍纳米线,然后在800℃下氧化8h得到NiO纳米线。利用X射线衍射(XRD)、原子力显微镜(AFM)和扫描电子显微镜(SEM)对NiO纳米线的组成、结构和形貌进行了表征,并测试了NiO/AAO阵列体系的光电压。测试结果表明:NiO纳米线为面心立方结构,平均晶粒尺寸为50nm,纳米线直径约90nm,与模板孔径相当;长度约为25μm,并受镍纳米线沉积时间的影响;在紫外灯(365nm)照射下,40V比60VNiO/AAO阵列体系的光电压大。     

多孔氧化铝膜制备金纳米线阵列

利用二次阳极氧化法制备了多孔氧化铝模板,用交流电化学沉积方法成功地在模板孔道内制备了Au纳米线。采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)对Au纳米线的形貌、晶体结构进行了研究。结果表明,模板的孔径均匀,孔道平直。Au纳米线均匀分布在PAA纳米孔中,直径与PAA孔径一致,约50 nm,且为多晶结构。     

利用配位反应法制备多孔阳极氧化铝/氧化锌纳米线阵列

研究了一种新型的制备氧化锌(ZnO)纳米线的配位反应法.以氨水为配位剂、氨水与可溶性的锌盐反应配制的锌氨配合物溶液为前驱液,在多孔阳极氧化铝(porous anodic alumina,PAA)模板中沉积了ZnO纳米线.研究了ZnO纳米线的生长机理和配位反应条件.用X射线衍射仪、扫描电子显微镜和透射电子显微镜对PAA/...     

磁性纳米线阵列的制备与应用

介绍了以多孔氧化铝(AAO)和刻蚀高聚物为模板制备磁性纳米线阵列的方法,包括溶胶-凝胶法、化学沉积法和电沉积法等.结合磁性纳米线的研究现状,展望了磁性纳米线阵列在磁记录、巨磁电阻、量子磁盘和高密度磁存储等方面的应用前景.     

ZnO纳米线阵列膜的自组装生长及其金属接触特性

以磁控溅射制备的ZnO纳米晶薄膜作为籽晶层,用水热法在80℃氧化铟锡(indium tin oxide,ITO)玻璃衬底上,实现了大面积ZnO纳米线阵列膜的取向生长,制备了3种金属-半导体-金属(metal-semiconductor-metal,MSM)结构的ZnO半导体纳米线阵列膜样品,测试了薄膜样品的光学特性和I-V特性。结果表明:在相同的生长液浓度下,籽晶层对所生长的纳米线尺度分布有显著影响。所制备的纳米线薄膜在室温下具有显著的紫外带边发射特性。ZnO纳米线/Ag和ZnO纳米线/Al的金属-半导体接触均具有明显的Schottky接触特性,而ZnO纳米线/Au的金属-半导体接触具有明显Ohmic接触特性。     

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.     

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。