玻璃基板澄清过程中一种氧气泡产生的机理及其控制方法

玻璃基板生产中,玻璃液的熔化、澄清、均化、冷却过程中广泛使用耐热金属铂及其合金组件,铂及其铂合金与玻璃液接触时两者界面会产生大量气泡。本文针对澄清部到出料口位置分析了气泡产生的原因,并且得出用于抑制界面气泡生成的环境湿度控制方法。     

耐火材料在玻璃中析出气泡的趋势

众所周知,气泡,即渗入玻璃中的气体,是玻璃主要缺陷之一。渗入大量气泡会破坏玻璃的均一性,减少透光性,降低机械强度和热稳定性。玻璃中气泡的形成与一系列原因有关,其中包括耐火材料与玻璃在接触界面相互作用。相互作用结果产生的气泡,可能出现玻璃内部或玻璃表面处的缺陷。 为了提高玻璃产品质量,需要选择合炭更少的耐火材料,应用在玻璃熔窑的冷却部和成型部,使用时减轻玻璃中形成气泡的程度。 本文所做工作目的,主要是确定测定方法以估价耐火材料在玻璃中析出气泡的趋势,电熔耐火材     

超白玻璃生产中耐火材料气泡的分析与对策

某浮法玻璃生产线在超白玻璃生产期间,出现大量气泡缺陷,在板带分布没有明显规律,厚度上位于玻璃板的中下部。经过检测分析气泡成分主要包含氮气(N_2)、二氧化碳(CO_2)、氩气(Ar),判断气泡缺陷来自于熔窑澄清部池底的耐火材料侵蚀。经过采取措施,降低熔窑澄清部池底耐火材料与玻璃液界面处的温度和玻璃液的流动性,达到了解决气泡缺陷的目的。在熔窑放完玻璃水后,检查熔窑澄清部池底耐火材料被侵蚀情况,印证了气泡缺陷来源的判断。     

铂及其合金在硼硅酸盐玻璃中的应用

基于铂及其合金的性能,通过对其分析与讨论,提出其应用场景变化对铂及其合金的要求。针对硼硅酸盐玻璃质量要求高,熔化、澄清、成形困难的特点,提出了铂及其合金在硼硅玻璃中的应用及其注意事项。     

玻璃液温度测量热电变换器

玻璃液温度是表征熔窑作业的主要参数之一,它需要长时间地连续测定。为此,一般采用热电变换器,其感温元件是用铂铑及铂做的热电极(Tnn)或铂铑电极(Tpp)组成的热电偶。温度测量范围分別为0～1300℃和300～1600℃。为了防止熔融玻璃液对变换器感温元件的损坏作用,一般把它装在一个用铂、铑合金制的保护罩里。然而所采用的保护装置也有许多缺点,主要是价格昂贵,且在高温下机械强度低。     

从玻璃液中打捞钢板的尝试

铁器掉进玻璃液中是十分有害的,它将使玻璃制品长期产生气泡,不但影响产品质量,而且也影响产量.我厂在上一个窑期,四机无槽投产初期,热修吊平碹和热换大梁砖的过程中,螺栓、钩子、钢管等铁器不慎掉入成形通路的玻璃液中,造成玻璃原板上产生大量气泡,大气泡长达几十厘米.由于气泡而扣尺,产量下降;由于玻璃板上有气     

光伏压延玻璃硅珠结石产生机理与分析

利用岩相分析、电子探针和光学显微镜,对光伏压延玻璃生产线产生的玻璃硅珠结石缺陷进行分析,鉴别出硅珠类结石为单质硅结石,来源于玻璃液中二氧化硅与杂质铝反应生成,同时伴随气泡产生,并对玻璃硅珠结石缺陷问题提出了有效的解决方法,为全氧燃烧窑炉压延玻璃生产提供了技术参考。     

玻璃窑炉耐火材料(下)

4.耐火材料的临界使用性质及玻璃工业所用耐火材料的试验 A、腐蚀作用 (1)与玻璃液接触部位。在生产窑炉中,腐蚀通常不是均匀地在与玻璃液接触的硅的整个表面上发生的。在液面线处,即在气—液—固三相界面处腐蚀是加速进行的,此处腐蚀速度为液面以下的几倍。但玻璃液面以下的腐蚀也可能很快,这是由所谓向上钻蚀所造成的,这种钻蚀亦包含着气—液—固三相界面的腐蚀作用。当玻璃液与耐火材料向下的表面接触,并且在该耐火材料表面的下面捕获了一些气泡时,就发生了这种钻蚀作用。鞋底钉或其它金属掉到窑炉中也会加速     

新型节能硅砖引起的玻璃气泡及其对策

采用光学偏光显微镜、扫描电镜-X射线能谱仪、气泡分析质谱仪分析了气泡内壁沉积物的形貌、化学组成和气泡内气体的成分,推断出气泡产生的位置和原因：熔窑碹顶所用新型节能硅砖中含有SiC,在升温过程中局部发生破碎产生碎砖渣,在加入碎玻璃和配合料前碎砖渣掉入熔窑,随玻璃液移动到工作部末端,与玻璃液反应形成气泡。最后,提出解决气泡缺陷的方案,应用效果良好。     

玻璃熔融过程中的澄清

具有气泡的钠钙玻璃熔液的澄清机理,从本文的照片和文献数据中即可了解其概况。气泡是随熔融体的温度升高而逐渐消失。而且气泡的大小和时间形成直线的关系。同时本文阐述了气泡在玻璃澄清过程中生成非均质晶核的理沦问题。在全熔融时间里使矿石和气泡从玻     

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。