高浓度的水热法合成四方晶相的摩尔分数为3%的Y2O3—ZrO2微粉

本文介绍了采用高浓度的（相当于5mol/LZr)氧氯化锆为母盐溶液，在75℃下与氨水进行沉淀反应，然后进行水热反应来合成ZrO2微粉，最初制备的粉末是由原生的超微ZrO2晶粒构成的、暂时性的团聚球粒，放入水中后团聚粒子消失而形成半透明的溶胶，在250℃下干燥处理5h形成团聚粒子，再将其制成含有适量YCl3的悬浮体，加入5g尿素/L溶液，在90℃下加热2h后进行离心分离、水洗除去Cl^-离子后进行微波干燥，最后在800℃下煅烧1h可得到一次粒径为42nm，团聚粒径为0.36um，含3%Y2O3（摩 尔分数）的单分散的四方晶型的ZrO2微粉。     

（Y2O3·CeO2）-ZrO2纳米粉的制备

用化学沉淀法合成了Y2O3、CeO2共掺杂的ZrO2纳米粉。通过XRD、TEM和粒度分布仪等检测手段对产品进行了表征,结果表明:Y2O3含量为2mol%,CeO2含量为9mol%时,在550℃得到了全稳定立方相ZrO2,粒径约为58.8nm。     

Phase Transformation and Melting Behavior of Silica Fumes

借助于 X 射线荧光仪、场发射扫描电子显微镜、能谱仪、X 射线衍射仪和激光粒度仪研究了 3 种不同产地的氧化硅微粉在常温和 800～1200℃热处理 3h 后的形貌、粒径分布、相变和熔融行为。常温下 3 种氧化硅微粉均为粒径小于 1μm 的圆球，可分辨的圆球粒径为 30～50nm，部分小球黏附在大球表面。圆球粒径大小不同，粒径大于 1μm 的多为团聚体。所有氧化硅微粉热处理至 800℃都为非晶态，至 900℃热处理后开始方石英化，1 200 ℃热处理后生成鳞石英。800 ℃热处理后，部分氧化硅微粉出现轻微黏结现象，随温度升高出现变形和熔融软化，在 1 200 ℃热处理 3 h 后，所有氧化硅微粉均呈熔融状。不同氧化硅微粉的相变和熔融行为与粒径分布和 Na2O、K2O 的含量有关，含 ZrO2的氧化硅微粉经 900 ℃热处理 3h 后出现 t-ZrO2，温度继续升高后未观察到进一步相变。     

球磨及立磨矿渣微粉颗粒特征及性能研究

用扫描电镜和激光粒度分析仪研究了球磨和立磨生产的矿渣微粉颗粒形貌和颗粒群分布。结果表明，球磨与立磨矿渣微粉颗粒形貌差别不大；矿渣微粉d50与比表面积有较好的相关性，两种产品均符合RRB分布，立磨矿渣微粉粒度分布范围较窄；立磨矿渣微粉的掺入对水泥标准稠度用水量、胶砂流动度和凝结时间的影响比球磨矿渣微粉大；掺立磨矿渣微粉的水泥各龄期强度均比掺球磨矿渣微粉的水泥低，立磨生产时矿渣微粉比表面积控制在400m^2／kg左右可能较为合理。     

多晶硅水性切削液除硅研究

以废切削液回收PEG后剩余的废砂为原料,采用酸溶和碱溶两种方法除去废砂中的多晶硅杂质,回收SiC微粉,并对两种方法的可行性及工艺条件进行了研究。结果表明,酸法除硅时,当HF浓度为4 mol/L,硝酸浓度为2 mol/L,温度为35℃,反应时间为70 min时,可使回收微粉中硅杂质含量在0.1%~0.2%。碱法除硅时,当NaOH的溶液3%左右,温度在70℃,反应时间2 h,可使回收微粉中硅杂质含量在0.2%~0.3%。粒度分析表明,酸法及碱法回收产品粒径分布均能满足指标要求,且碱法回收产品粒径分布与新砂一致。     

不同干燥方法处理前驱体对ZrO_2粉体的影响

采用电热、冷冻、喷雾干燥法对化学沉淀法制备的ZrO2前驱体进行干燥后,在600℃下保温2h进行煅烧,并对ZrO2前驱体及煅烧产物进行物相表征,对ZrO2煅烧产物形貌及粒度分布进行分析。研究表明,采用不同的干燥方法制备的ZrO2粉体形貌和粒度分布不同,其中喷雾干燥制备的ZrO2粉体分散性最好,粒度分布窄,粒径较小,平均粒径达到85nm。     

ZrO2载体的制备及Ru-Fe-B/ZrO2催化剂的苯选择加氢制环己烯催化性能

以氯氧化锆(ZrOCl2.8 H2O)和碳酸氢铵(NH4HCO3)为原料,采用化学沉淀法制备了二氧化锆微粉。X射线衍射、N2物理吸附和激光粒度分析等测试结果表明,制得的ZrO2粉体以单斜相存在,微晶尺寸42.9 nm,具有典型的介孔结构,孔径范围4.5~50 nm,平均粒度1.5μm。进一步通过化学还原法制备了高活性高选择性Ru-Fe-B/ZrO2苯选择加氢制环己烯催化剂。在150℃,5 MPa氢压下,考察了负载型催化剂Ru-Fe-B/ZrO2的活性和选择性。结果表明,在Ru-Fe-B/ZrO2催化剂上,苯转化81.3%时,环己烯选择性高达70.4%,同时环己烯选择性随苯转化率升高而缓慢下降。     

ZrO2陶瓷粉末的制备方法

ZrO2陶瓷由于其独特的相变效应与高温氧离子导电现象使其得到越来越广泛的应用。在制作ZrO2陶瓷的过程中，制得性能优良的粉末是关键的第一步。性能优良的粉末粒度要细且粒度分布范围窄。此外，超细粉具有强烈的扩散能力，在烧结后期容易达到高密度甚至完全致密化。     

矿渣微粉颗粒群几何特征的图像分析

以QUANTITATIVE60 0图像分析仪为测试手段 ,由矿渣微粉的二维截面图像推断出其三维结构特征 ,同时获得矿渣微粉试样的级配 (大小、分布曲线 )、颗粒形状因子 (圆度、长短径之比 )等一系列颗粒群特征三维参数。结果表明 :①矿渣微粉颗粒群的累计质量 粒度分布符合Rosin Rammler分布和修正的Gauss分布 ,其中Rosin Rammler分布可以得到很高相关性的拟合直线 ,而Gauss分布能直观地反映粉体颗粒群的分布情况 ;②矿渣是颗粒状粉体 ,用圆度 粒度、长短Feret径之比 粒度、CurveLength 粒度和CurveWidth 粒度分布来描述矿渣微粉颗粒群的形状特征具有较好的规律性。矿渣微粉颗粒群的细组分更接近于球体 ,而粗组分更接近于长方体     

溶胶-凝胶法制备ZnO微粉及其电学性质

以柠檬酸和柠檬酸三铵为络合剂,利用溶胶凝胶法制备ZnO微粉。在乙酸锌浓度为0.2mol/L、柠檬酸浓度为0.05mol/L时得到的ZnO微粒粒径较小;在乙酸锌浓度为1.0mol/L、柠檬酸三铵浓度为0.5mol/L、灼烧温度为600℃时得到的ZnO微粒粒径较小。并分别对其性能进行表征,包括激光光散射粒度分析、红外检测、X 射线衍射分析、电学性质测定(阻抗、伏安特性曲线)。     

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。