超微粉体材料需求增大

超微粉体材料市场前景十分广阔 ,据悉 ,今年全球对超微粉体材料的需求量将达到 3.2万ｔ。近年来 ,一些国际著名化学公司纷纷发展超微粉体材料工业 ,如 :德国、美国和日本已出现了超微粉体材料专业开发公司。日本是精细陶瓷研究开发比较早的国家 ,90年代 ,日本和西欧生产新型陶瓷用超微粉体材料的总产值分别为 1 5.8%和 1 8.9% ,预计进入 2 1世纪 ,超微粉体材料的应用在机械领域约占 4 0 .3% ,热能领域占 34 .6% ,电磁领域占 1 2 .9% ,生物医学占 8.9% ,光学领域占 2 .4 % ,其他方面占 0 .9%左右。我国已建立了一些超微粉体材料生产企业 ,有…     

超临界流体技术在制备超微粉体中的应用

SCF制备超微粉体是一项新技术。利用SCF较好的溶解、扩散和传输能力 ,能制备出性能优异的超微粉体。本文对RESS、SAS和SCF微乳液法制备超微粉体的原理进行了总结 ,并对其在化工材料、医药、食品等领域中的研究现状进行了介绍     

气流粉碎/静电分散与球磨制备超微粉体粒度对比研究

气流粉碎作为一种先进的超微粉体制备技术被广泛运用在工业生产中,然而气流粉碎后的颗粒将会自发团聚,从而影响到气流粉碎所制备超微粉体的优异性能,通过结合静电分散可使所制备的超微粉体保持较好的分散性。文中分别利用气流粉碎/静电分散法及高能球磨法制备了CaCO_3超微粉体,得到了两种方法所制备超微粉体的粒度分布规律,并对比分析了两者之间的优劣,结果表明气流粉碎/静电分散能够有效阻止所制备超微粉体的团聚产生,荷电电压越高则所制备超微粉体的平均粒度越小,而球磨所制备的超微粉体颗粒之间存在严重的团聚现象,颗粒粒度及其分布区间较大。     

超临界流体技术在制备超微粉体中的应用

SCF制备超微粉体是一项新技术。利用SCF较好的溶解、扩散和传输能力，能制备出性能优异的超微粉体。按其工艺原理可分为：SCF快速膨胀法(RESS)、SCF反溶剂法(SAS)和SCF微乳液法。本文对RESS、SCF反溶剂法(SAS)和SCF微乳液法制备超微粉体的原理进行了总结，并对其在化工材料、医药、食品等领域中的研究现状进行了介绍。     

超临界流体制备超微粉体的研究进展

超临界流体制备超微粉体是一项新技术，利用超临界流体较好的溶解、扩散和传输能力，能制备出高质量的超微粉体，根据其工艺原理可分为：超临界流体快速膨胀法（RESS），超临界流体脱溶剂法（GAS）和超临界流体微乳法，本文对RESS，GAS和超临界流体微乳法制备超微粉体的原理进行了总结，并对这3种方法在食品、医药、化工材料等领域中的研究现状进行了介绍。     

HTC高效涡轮超微分级机在浙江丰利问世

一种高性能、适用性广的新一代超微粉体材料分级机———ＨＴＣ高效涡轮超微分级机,由浙江丰利粉碎设备有限公司与国际知名粉碎机制造商德国霍伯尔工程公司强强合作,利用流体力学的变速涡轮分级原理研制而成,日前通过了浙江省科技成果鉴定。专家认为该机解决了超微粉体材料的分级难题,是粉体工程技术的一项重大突破。被誉为21世纪新材料的“超微粉体材料”,以其能大幅度地提高材料的附加值和利用率,用途广泛,经济和社会效益显著而列入了《当前国家优先发展的高新技术产业化重点领域指南(目录)》。随着我国高技术及新材料产业的发展,对超微粉…     

超微粉体技术发展展望

进入21世纪以来，信息、生物和新材料等技术带动了超微粉体技术研究的深入发展。超微粉体已获广泛应用，它不仅在高科技领域有着不可替代的作用，同时，也给传统产业带来生机和活力。超微粉体技术的一个突出的发展趋势是纳米化。随着科学与工业技术的进步，超微粉体技术作为一种工程学科在国民经济的发展中正扮演着举足轻重的角色。因此，世界各国，特别是美、日、欧对其发展的关注更为突出。     

超微粒子氧化物

日本水泥公司开发超微细粒子氧化物有氧化铝、氧化锆等精细陶瓷原料以及颜料用钛黑,氧化铁。另有锰铁氧体,镍铁氧体氧化物,无论那一种产品,粒径均是0.1～0.01μ的超微粉。它是分散的粒子,粒度分布范围非常小,纯度极高,表面具有亲油和亲水性,与一般产品比较,比表面积高。该公司开发独自的超微粉技术,可改变     

HTC高效涡轮超微分级机在浙江丰利问世

一种高性能、适用性广的新一代超微粉体材料分级机———ＨＴＣ高效涡轮超微分级机 ,由我国知名的超微粉碎设备生产基地浙江丰利粉碎设备有限公司与国际著名粉碎机制造商德国霍伯尔工程公司强强合作 ,利用流体力学的变速涡轮分级原理研制而成 ,日前通过了浙江省科技成果鉴定。专家认为该机解决了超微粉体材料的分级难题 ,是粉体工程技术的一项重大突破 ,产品填补了国内空白 ,其技术处于国内领先水平。随着我国高技术及新材料产业的发展 ,对超微粉体材料的需求越来越大 ,需要大批粒度在 8μｍ以下的高纯度超微粉体材料 ,以满足各行业的需求。…     

溶胶—凝胶法制多孔玻璃原料前驱体微粉

本文以硅酸乙酯、氢氧化钠、硼酸为原料用溶胶－凝胶法制备了硼硅酸盐超微粉，研究了各个过程参数对超微粉体性能的影响。     

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。