水性环氧-丙烯酸酯复合纳米涂层的制备及其防腐性能

先以Fe Cl_2和Fe Cl_3为原料,用化学共沉淀法制备了Fe_3O_4纳米粒子,再在其表面包覆Si O_2制得Fe_3O_4@Si O_2颗粒,然后将Fe_3O_4@Si O_2颗粒与水性环氧-丙烯酸酯乳液混合制备了复合涂层。采用透射电镜、红外光谱仪和X射线衍射仪表征了Fe_3O_4纳米粒子改性前后的形貌和晶体结构。通过塔菲尔极化曲线和浸泡试验考察了纳米粒子对复合涂层在自来水、3.5%(质量分数)HCl、3.5%Na OH和3.5%Na Cl溶液中耐蚀性的影响,并探讨了涂层的防腐机理。Si O_2成功包覆到Fe_3O_4粒子表面,提高了其与水性环氧–丙烯酸酯乳液的相容性,显著改善了复合涂层的防腐性能。     

SiO_2纳米胶囊的细乳液法制备及其载药性能研究

在细乳液反应体系中,以阳离子型乳化剂稳定的纳米油滴为模板,通过正硅酸乙酯(TEOS)的界面水解-缩合反应制备Si O_2纳米胶囊,并将其用于装载姜黄素。采用动态光散射和透射电镜研究了Si O_2纳米胶囊的尺寸和形态;采用红外光谱和热失重测试研究了Si O_2纳米胶囊装载姜黄素的能力;采用紫外-可见分光光度计研究了装载姜黄素的Si O_2纳米粒子的姜黄素缓释动力学。结果表明:细乳液法能高效地制备Si O_2纳米胶囊,其尺寸和壳壁稳定性能通过阳离子乳化剂和TEOS的用量调控;Si O_2纳米胶囊能高效地装载姜黄素,且对其有一定的缓释效果。     

纳米SiO_2对Sr_(0.98)BaSiO_4:0.02Eu绿色荧光粉性能的影响

以纳米和微米Si O_2为原料,采用高温固相法合成了Sr_(0.98)Ba Si_xSi-(1-x)O_4:0.02Eu(其中,x表示纳米Si O_2的含量,x=0-1.0)一系列绿色荧光粉。结果表明:原料中掺入纳米Si O_2后,可以有效改善荧光粉的发光强度、晶体形貌和尺寸,增强粉体稳定性,降低用粉量等。值得注意的是,当纳米Si O_2的掺杂比例为0.6时,所得粉体质量较佳。本研究为后期进一步改进绿色荧光粉的性能奠定了一定的实验基础。     

TiO_2/SiO_2复合气凝胶的制备分析

以酞酸丁酯和正硅酸乙酯为原料,在酸性条件下,溶胶-凝胶法制备Ti O_2/Si O_2复合气凝胶。采用SEM照片分析Ti O_2/Si O_2复合气凝胶为松散的颗粒状,粒径为100~200 nm;通过XRD分析确定煅烧前后Ti O_2/Si O_2复合气凝胶的晶型转变,确证Ti O_2/Si O_2复合气凝胶的成功制备;通过光催化降解分析表明:Ti O_2/Si O_2复合气凝胶对罗丹明B具有较好的吸附作用,且在150 min时罗丹明B基本降解完全。     

MXene和纳米SiO2对粉煤灰水泥水化性能的影响

本文利用差热分析、X射线衍射、扫描电镜等手段研究了纳米Si O_2和MXene对粉煤灰水泥水化性能的影响。结果表明,单掺纳米Si O_2能够促进粉煤灰水泥早期水化,提高水化开始时的放热速率,并使粉煤灰水泥浆体更加密实;而单掺MXene、复掺纳米Si O_2和MXene对粉煤灰水泥后期水化的促进作用比较明显,能够促进水泥中期强度增长。     

电沉积Cu-Zn-SiO_2纳米复合镀层工艺及耐蚀性研究

用电沉积方法在锌合金基体的表面制备Cu-Zn合金镀层和Cu-Zn-Si O2纳米复合镀层,采用扫描电镜(SEM)研究Cu-Zn合金镀层及其Cu-Zn-Si O2纳米复合镀层的表面形貌。采用络合滴定法和称重法确定掺杂纳米Si O2粉末的质量。采用浸泡法和电化学极化法(Tafel曲线)研究不同电镀时间的两类镀层在5.0wt%Na Cl和5.0wt%HCl溶液中的腐蚀行为。研究结果表明:纳米Si O2粉末的最佳掺杂量为2.0 g·L-1。通过与合金镀层比较,纳米复合镀层在5.0wt%Na Cl和5.0wt%HCl溶液中都表现出极好的耐腐蚀性能。此外,对不同施镀时间的纳米复合镀层耐蚀性能进行比较,最终确定适度最佳时间为4.0 min。     

纳米SiO_2及制备条件对聚偏氟乙烯微滤膜的影响研究

采用相转化法制备聚偏氟乙烯(PVDF)-纳米二氧化硅(n Si O_2)复合微滤膜,研究了n Si O_2投加量、制膜过程中的搅拌转速和搅拌时间对复合膜的影响,通过扫描电子显微镜、死端过滤实验、接触角测量、孔隙率、清水通量等,分别对不同膜的微观结构、抗污染能力、表面亲水性、分离性能进行了联合表征。结果表明,n Si O_2的引入能有效改善膜的抗污染性能,以n Si O_2的质量分数为0.05%为最佳;随着搅拌转速的增大,膜亲水性能、分离性能均有所提高,当搅拌转速为800 r/min、搅拌时间以4 d时,膜性能最优。     

玻璃负载纳米TiO_2/SiO_2膜的制备和光催化性能

制备了玻璃负载纳米Ti O_2/Si O_2光催化膜,以甲基橙溶液作为模拟废水研究了其光催化性能,分别考察了光催化膜中m(Ti O_2)∶m(Si O_2)、膜厚度、使用次数和中试扩大以及再生方式对甲基橙模拟废水降解率的影响。试验结果表明,在太阳光下照射4 h,厚度为200~400 nm的光催化膜对10 mg/L的甲基橙模拟废水降解率为84%,失活的光催化膜可用模拟风、光、酸雨和人工清洗方式再生。纳米Ti O_2/Si O_2光催化膜可应用于光催化水处理设备、建筑易清洁玻璃和太阳电池玻璃。     

纳米复合电镀层的研究

纳米复合电镀是获得纳米复合镀层的一种新工艺,能够很好地提高镀层的性能。纳米复合电镀层比一般的复合镀层具有更好的耐磨性、耐蚀性和更高的硬度。本文介绍了纳米粒子复合电镀层的结构及具有耐磨性能、耐腐蚀性能、自润滑性能、抗高温氧化性能和催化性能等不同功能的纳米复合电镀层,并对纳米复合电镀的发展前景进行了展望。     

纳米复合镀镍研讨会

中国电子学会生产技术学分会电镀专业委员会于 2 0 0 2年 1月 7日在重庆召开了纳米复合镀镍研讨会 ,来自全国的会议代表共 30余名。中国电子学会生产技术学分会副主任委员 ,电镀专业委员会主任蒋宇侨先生出席会议并讲话。会议由中国电子学会生产技术学分会电镀专业委员会复合镀层研究会主任委员 ,天津大学应用化学系主任、博士生导师王为教授主持。西南师范大学博士生导师李声泽教授讲述了《高耐蚀耐磨纳米复合电镀浆料及其电镀工艺》。纳米 α-Al2 O3 复合电镀浆料使纳米粒子在高浓度的电解液中具有良好的分散性且不团聚 ,长期存放也能均…     

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。