熔融盐对氧化锆纳米片合成的影响EI北大核心CSCD

以四氯化锆为锆源,乙醇为溶剂,采用溶剂热辅助熔盐法低温煅烧制备氧化锆纳米片。研究并讨论了熔盐种类和用量对氧化锆晶体生长和形貌的影响。结果表明:以NaCl和Na3PO4的混合物为熔盐,且m(前驱体):m(NaCl):m(Na3PO4)=10:10:1时,可以得到平均边长超过1.8μm,厚约70 nm,宽厚比大于10:1的单斜氧化锆纳米片。纳米片为单晶结构,无明显缺陷,主要暴露面为(001)晶面,其在熔盐中的形成符合自聚焦机理,包括溶解、扩散、吸附和生长过程,(001)面主导的氧化锆纳米片与表面能的理论计算结果吻合。     

熔融盐对氧化锆纳米片合成的影响

以四氯化锆为锆源,乙醇为溶剂,采用溶剂热辅助熔盐法低温煅烧制备氧化锆纳米片。研究并讨论了熔盐种类和用量对氧化锆晶体生长和形貌的影响。结果表明:以NaCl和Na_3PO_4的混合物为熔盐,且m(前驱体):m(NaCl):m(Na_3PO_4)=10:10:1时,可以得到平均边长超过1.8μm,厚约70 nm,宽厚比大于10:1的单斜氧化锆纳米片。纳米片为单晶结构,无明显缺陷,主要暴露面为(001)晶面,其在熔盐中的形成符合自聚焦机理,包括溶解、扩散、吸附和生长过程,(001)面主导的氧化锆纳米片与表面能的理论计算结果吻合。     

Ag纳米粒子改性MoS_2/暴露(001)面TiO_2二维复合材料及其可见光催化性能研究

以钛酸四丁酯、氢氟酸、钼酸钠、硫代乙酰胺和硝酸银为原料,利用水热法和光沉积法成功在二硫化钼(MoS_2)/暴露(001)面TiO_2二维复合材料上沉积了银纳米粒子(Ag)。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、紫外可见吸收(UV-vis)对样品的相组成、表面形貌、表面元素组成和光响应范围进行表征测试,并在可见光下考察了复合材料降解亚甲基兰(MB)的光催化性能。结果表明粒径约为20~30 nm的Ag颗粒成功负载在MoS_2/暴露(001)面的TiO_2纳米片上(MT-001),Ag纳米粒子的等离子共振效应有效的改善了MT-001纳米片的光催化性能,改性后复合材料对MB的最佳降解率为89.72%,为同等条件下纯TiO_2纳米片的1.55倍。     

氧化石墨烯尺寸对水泥基复合材料的影响

采用Hummers法以石墨粉为原料制备氧化石墨烯(GO),采用球磨法制备不同尺寸的氧化石墨烯纳米片,分别使用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电镜(TEM)和马尔文激光粒度仪(Zetasizer Nano,Zs)进行结构表征.结果 表明,球磨法可制备不同粒径分布的氧化石墨烯纳米片;水泥基复合材料的SEM微观形貌以及力学性能测定结果显示当掺杂0.25％、球磨16 h制得的氧化石墨烯(80 ～ 184 nm),复合材料的抗折、抗压强度分别为12.1 MPa和73 MPa,相较于对照样品提高了47.56％和38.52％;小尺寸氧化石墨烯促进水泥内部形成规则有序的水化物,这些水化物在水泥内堆叠,形成相互交联的晶体网络,微观上改变复合材料内部结构,宏观上提高了其力学性能.     

Cr2O3晶体形貌模拟及纳米参数的计算研究

介绍了量子化学计算软件Material Studio的Morphology模块,采用BFDH法则对氧化铬晶体进行形貌模拟,得到其(001)和(001-)为最易外显面,显示几率达30.6435%.在晶体结构的基础上,运用晶体化学和纳米科技的基本原理,通过计算氧化铬不同粒径大小的总晶胞数、总原子数、总分子数目、以及表面原子数、晶胞数和表面原子所占的比例,分析和讨论了结构稳定性和化学活性与粒径的关系.对计算结果进行分析,得到氧化铬的最佳纳米化尺度是110 nm.     

纳米针状羟基磷灰石晶体的常压水热合成研究

利用正交试验法探讨常压下制备纳米针状羟基磷灰石(HA)晶体。用FTIR、XRD及TEM分析了HA的结构和形貌。讨论了前驱体的浓度、反应搅拌速度、pH值(当pH≥10时)及分散剂N,N-二甲基甲酰胺(DMF)含量对羟基磷灰石晶体形貌及尺寸的影响。结果表明:在合成条件变化很宽的范围内,可以制得纯度高、分散性好的纳米级针状HA晶体。这种纳米针状HA晶体与自然骨中的HA晶体在组成、结构、结晶度和形貌方面有十分相似之处。另外,正交分析表明分散剂含量及前驱体的浓度对制备纳米级针状HA晶体的长度影响较为显著,而HA晶体的长径比受搅拌速度和pH值影响较大。     

喷雾燃烧制备SnO2纳米棒及其气敏性能

采用喷雾燃烧法制备SnO2纳米棒,对其形貌和结构进行了表征. 所制SnO2纳米棒长200~350 nm,直径30~50 nm,沿(001)方向生长. 考察了Fe掺杂量和Sn4+浓度对SnO2纳米棒形貌的影响,分析了其生长机理. 高温快速反应使Fe3+进入SnO2晶格,促使其沿(001)方向取向生长. 对乙醇等有机气体的气敏性能测试结果表明,棒状SnO2比颗粒状的具有更优的气敏性能,在100′10-6(j)乙醇浓度下,棒状SnO2的灵敏度为12,反应和恢复时间分别为9.5和6 s.     

以天然石墨为原料制备纳米石墨片在有机溶剂中的分散液

以天然石墨为原料,采用球磨法制备纳米石墨片在有机溶剂中的分散液.考察了球磨时间、不同分散剂和分散剂含量以及树脂含量对纳米石墨片分散效果的影响.研究发现以天然石墨为原料,采用球磨工艺可以制备直径为5μm,厚度小于30nm的纳米石墨片.纳米石墨片分散液的稳定性随着球磨时间的延长、分散剂的增加先增大后减小;随着树脂含量的增加先显著增加,达到最高之后,略有降低.     

水热法制备Zn-Mg-Al花状水滑石

采用水热法,以尿素为沉淀剂,Zn(NO3)2、Mg(NO3)2和Al(NO3)3为原料,在120℃下连续反应10 h后制备了Zn-Mg-Al水滑石纳米片以及由纳米片组装成的花状结构水滑石。利用XRD、FTIR、TG-DTA、ICP和SEM分别对产物的尺寸、结构和形貌进行了分析。结果表明,合成的水滑石具有均一的花状形貌,花状晶体直径约8μm左右,构成花状结构的纳米片厚度约为100 nm,花状水滑石晶体具有良好的"记忆效应"。初步阐释了花状水滑石的可能形成机理。     

二氧化钛纳米片的合成及光催化性能

以钛酸丁酯为钛源,在乙醇与乙腈的混合体系中,一步法制备外露(001)面的TiO2纳米片。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和激光拉曼光谱仪等表征手段,分别对产物的形貌和结构进行了表征。考察了体系中乙腈和钛酸丁酯的浓度等因素对产物形貌的影响。并以亚甲基蓝为探针研究了产物的光催化活性。     

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.     

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.     

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。     

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.     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Some Large Wood-Boring Beetles in Southeastern USA

Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.