玄武岩纤维生产炉窑耐火材料侵蚀研究

以玄武岩纤维生产炉窑顶部加料口上部的刚玉莫来石砖和侧壁内衬高铬砖作为研究对象,采用XRD、XRF、SEM和EDX等分析方法,研究了玄武岩熔体对炉窑耐火材料的侵蚀行为,结果表明炉窑顶部的刚玉莫来石砖以50 mm/a侵蚀速率被侵蚀,刚玉莫来石砖内部的刚玉和莫来石晶粒与玄武岩反应生成低熔点的钙长石、橄榄石、铁尖晶石等物质,同时受到挥发分气流的物理性冲刷,导致刚玉莫来石砖耐侵蚀性能差;而炉窑内侧壁高铬砖耐侵蚀性较好,腐蚀速率为2. 5 mm/a,高铬砖与熔体接触区以化学反应结合物理磨损侵蚀方式为主,同时,Fe元素在高铬砖侵蚀过程中起着固溶-传质的作用,加速炉衬材料侵蚀。     

HIsmelt工艺熔融还原炉用耐火材料的抗侵蚀性研究

为促进HIsmelt工艺的进一步发展和应用，根据HIsmelt工艺熔融还原炉(SRV)的特点，利用静态坩埚法对比研究了SRV渣在1 500℃下对铬刚玉砖、微孔刚玉-莫来石砖、刚玉-莫来石砖、刚玉-尖晶石砖的侵蚀。结果表明：1)铬刚玉砖抗SRV渣渗透侵蚀能力最强，因为FeO与铬刚玉砖中的Al₂O₃和Cr₂O₃反应生成高熔点物，抑制炉渣的渗透和侵蚀。2)微孔刚玉-莫来石砖中镁铝尖晶石与钙铝黄长石的生成在侵蚀层形成保护层，阻止SRV渣的渗透侵蚀，在3种无铬材料中，表现出最优的抗侵蚀性。3)刚玉-莫来石砖中由于大量钙长石的形成产生的缝隙造成渣的不断渗入，使得熔渣对砖的侵蚀较严重。4)刚玉-尖晶石砖中原位生成粒径小、活性高的尖晶石晶粒，能有效吸收熔渣中的铁离子形成镁铝铁复合尖晶石，阻挡SRV渣的侵蚀。     

耐火材料抗碱蒸气侵蚀性研究

以高纯刚玉砖、刚玉-莫来石砖、莫来石砖、六铝酸钙砖、六铝酸钙-刚玉砖为研究对象,探究了5种耐火制品在1370和1500℃碱蒸气侵蚀下的反应状态及抗碱蒸气侵蚀机制.结果表明:1)在高温碱蒸气环境下,高纯刚玉砖无明显渣层,反应膨胀明显.2)刚玉-莫来石砖在1370℃时反应膨胀较为明显,1500℃时转变为熔蚀.3)1370℃...     

塑性相结合刚玉复合砖的高温性能

通过设定高炉使用条件 ,将塑性相结合刚玉复合砖与现在高炉使用的刚玉莫来石砖及棕刚玉碳化硅砖在同等实验条件下进行了高温性能的比较。结果表明 :塑性相结合刚玉复合砖的结构致密 ,高温抗折强度高 ;而且在高温还原气氛下 ,其基质中的Si可与C和N2 反应 ,生成具有良好抗炉渣、铁水和碱金属侵蚀能力的碳化物和氮化物 ,并填充表面的间隙 ,形成一个良好的防护层 ,因此其抗侵蚀性能优于棕刚玉碳化硅砖和刚玉莫来石砖。     

高温炭黑反应炉炉衬选材分析

本文从抵抗高温气流冲蚀,抗炭黑粒子化学侵蚀和抵抗炉气杂质化学侵蚀等三个方面分析比较了高纯刚玉砖,刚玉莫来石砖、铬刚玉砖,高铬砖和氧化锆砖。讨论分析认为：在燃烧室和喉管采用高纯刚玉砖和铬刚玉砖,反应段和急冷段采用高纯刚玉砖较好;氧化锆砖在整个反应炉各段使用都是可行的,高铬砖因抗炭黑粒子化学侵蚀性差,不适合使用于高温炭黑反应炉。     

高温炭黑反应炉炉衬选材分析

从抵抗高温气流冲蚀、抗炭黑粒子化学侵蚀和抵抗炉气杂质化学侵蚀等三个方面对高纯刚玉砖、刚玉莫来石砖、铬刚玉砖、高铬砖和氧化锆砖作了分析比较。分析认为,在燃烧室和喉管采用高纯刚玉砖和铬刚玉砖,反应段和急冷段采用高纯刚玉砖较好;而氧化锆砖在整个反应炉各段使用都是可行的。高铬砖因抗炭黑粒子化学侵蚀性差,不适合使用于高温炭黑反应炉     

危废处置回转窑用典型耐火材料抗熔渣侵蚀性能研究

对比了危废处置回转窑用几种典型耐火材料铬锆刚玉50砖、铬锆刚玉30砖、铬刚玉砖、高铝砖、刚玉莫来石砖和铝铬碳化硅砖分别在1100和1300℃的抗熔渣侵蚀性能.结果表明:1)在1100℃侵蚀试验后,6组试样均表现出较好的抗侵蚀性能和抗渗透性能,试验后坩埚内都残留了大量熔渣.2)在1300℃侵蚀试验后,6组试样的熔渣侵蚀和...     

鲕状高磷赤铁矿超细粉的气基还原实验研究

使用新开发装置对高磷赤铁矿超细粉进行气基还原实验研究.该矿中P主要以磷灰石形式嵌布于鲕状赤铁矿和其他脉石颗粒之间,但Fe和P元素未处于化学结合状态.采用超级涡流磨技术将高磷赤铁矿磨成平均粒度为2μm的超细粉,实现Fe和P元素较好的解离.还原实验结果表明,使用新开发的还原装置实现了矿粉的高度还原;粒度对还原结果的影响最显...     

酸性铬铁渣对耐火材料侵蚀的试验研究

为了研究冶炼铬铁的竖炉炉缸用耐火材料受酸性渣侵蚀情况,利用化学试剂CaO、MgO、SiO2、Al2O3和铬铁矿配制了不同碱度(分别为0.31、0.45和0.55)的酸性铬铁渣,采用静态坩埚法,分别在1500℃、1550℃、1580℃保温3h条件下,对高铝质、莫来石质、铝碳质、铝碳化硅质、刚玉-莫来石质、刚玉质和棕刚玉-碳化硅质等耐火材料进行侵蚀试验,比较了不同耐火材料被侵蚀和渗透的程度。试验结果表明:随着铬铁渣碱度和温度的增加,耐火材料的侵蚀量都有所增加;铬铁渣对铝碳砖的侵蚀和渗透程度均很轻,对莫来石砖和棕刚玉-碳化硅砖的较轻;而对刚玉、刚玉-莫来石砖渗透程度很严重,但侵蚀很轻;对高铝砖和铝-碳化硅砖侵蚀程度严重。     

高磷鲕状赤铁矿直接还原制铁工艺研究

高磷鲕状赤铁矿由于含磷高、品位低、氧化铁晶粒嵌布粒度细等原因无法精选富集。对高磷鲕状赤铁矿的直接还原制备铁精矿的工艺进行了系统研究,发现在还原温度为1 250℃,还原剂为40%的密云无烟煤,添加剂石灰石用量为15%(质量分数),还原时间为30 min时,黑石板铁矿的Fe品位最高,磷的品味也较好。铁精矿的品位可以达到96.08%,铁精矿中磷的品位为0.171,磷的回收率为19.80%。     

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。