连续式碳纤维自发热机场道面温升规律试验研究

针对布置连续式碳纤维线的自发热机场混凝土道面,分别制作了内设6K、12K、24K发热线的水泥混凝土板,并在不同室外环境、不同输入功率下进行了温升规律现场试验。试验结果表明:1距离发热线越近,温升越快,温度越高;2发热线间距为10cm时,板面不同位置的温差在3℃以内,温度均匀性良好;3温升效果主要由输入功率决定,当环境温度在-10℃且输入功率为382W/m2时,3.5h后板面温度即可超过3℃;4自然环境对板面温升影响显著,板面温度变化与环境温度变化趋势一致,环境温度降低3℃,板面温度将会随之降低20%以上;5混凝土道面板散热慢,可以利用余热进行融雪化冰。     

碳纤维混凝土机场道面融雪化冰的影响因素

碳纤维混凝土具有良好的电热效应,可将其用于机场道面的融雪化冰,该方法是当前机场融雪除冰的方式之一。文章探讨了影响碳纤维混凝土机场道面融雪化冰的因素,主要包括碳纤维混凝土层厚度,通电时间及碳纤维掺量,粗骨料粒径,裂缝宽度,环境温度与冰层厚度,除冰功率等。     

连续式碳纤维电热机场道面融雪化冰数值模拟与验证

为了研究连续式碳纤维发热线的埋深和间距会对机场道面混凝土板表面的温度均匀性产生的影响,以及XPS隔热层的布设对板面融雪化冰效果的优化程度,利用有限元分析软件Ansys建立连续式碳纤维电热机场道面板温升及融雪化冰的瞬态传热模型,主要模拟道面板的温升及化冰过程,结果发现:在连续式碳纤维发热线布置间距≤100 mm、埋深≥50 mm时,板面温度均匀性良好;通过"有效融化时间"和"能源有效利用率"的定量计算,证明XPS隔热层的布设起到了良好的隔热保温的效果,为其在机场道面融雪化冰中的应用提供一定的理论依据.     

具有融雪功能的连续碳纤维电热混凝土路板的研制

本文利用连续碳纤维的电热性和高强性,把连续碳纤维铺放在混凝土中,研制出具有融雪功能的电热混凝土路板,提出在混凝土中铺设"加热带",而非整个路面全部加热的思路,达到减少制造成本的目的.确定了"加热带"宽为500mm,碳纤维到混凝土表面距离为15～20mm,碳纤维束的间距为12mm,最大设计功率设定为700W/m2.进行缩比样实验,实验结果表明,电热混凝土板加热均匀,升温速度适当,在-13℃左右、风速较低的情况下采用200～300W/m2的输入功率可使所降的中雪落地即融化.     

Φ4.2m×13m水泥磨系统增设V型选粉机的改造

正我公司下属九江公司2号水泥粉磨系统,配置了Φ1.6m×1.2m辊压机、SF650/160打散机及Φ4.2m×13m开流磨,辊压机功率为900k W×2,磨机功率3 550k W,设计生产P·O42.5水泥台时产量为145t/h,80μm筛筛余3%,工序电耗为29k Wh/t以下,入辊压机物料综合水分要求在1.2%以下,于2011年7月26     

固相反应法快速制备FeSb2及其电学性质研究

采用高温固相反应法,在773～923 K的温度范围内考察了FeSb2的生成规律.制备出的样品进行了XRD和SEM分析,并对样品的电阻率和Seebeck系数进行了测试分析,结果表明:在温度883 K保温3 h的制备条件下,可以合成单相的多晶体化合物FeSb2.制备出的样品内部存在不均匀的微米级孔洞.样品在测试温度为511.63 K时获得最大的Seebeck系数36.34μV/k,在453.72 K时获得最大功率因子188.68μW/(m·K2)     

节能新技术在有机硅废气处理中的应用

介绍了有机硅单体生产中废气处理的工艺原理及流程,分析了现有技术的缺点并提出了有效的改进措施,开发了有机硅废气处理节能新技术。经该技术处理后,柴油使用量由70~80 L/h降低至40~43L/h,耗电量由410 k W·h降低至287 k W·h,环保和节能效益显著。     

中小型污水处理厂自动控制系统及其节能降耗效能

以白山市污水厂CAST工艺为例,探索了中小型污水处理厂的节能降耗措施,重点分析了自动控制过程的节能降耗效能。结果表明,采用自动控制等节能措施后,耗电量约在0.3 k W·h/m3左右,在保证出水水质达标的前提下可实现节能降耗。     

Ф3.8 m×13 m水泥磨产量翻倍的技术改造

<正>1改前系统运行情况介绍平凉祁连山水泥有限公司2004年投产的2 500t/d新型干法水泥生产线,配套了2条Ф3.8 m×13 m(尾卸磨,中心传动,电机功率:2 500 k W)闭路水泥粉磨生产线,单条线产量为75t/h(P·O 42.5)。其中#2水泥粉磨线采用了常规的闭路工艺流程(流程图略),其主要配套设备有:N-2000型的O-SEPA 2000(改进型)选粉机,其电机功率132 k W,生产能力60~100 t/h;气箱脉冲袋式收尘器,其处理风量     

辊压机双闭路联合粉磨系统节电措施分析

针对粉磨系统中存在的最大瓶颈——成品选粉机子系统进行改造,将选粉效率较低的O-Sepa N-3500成品选粉机及系统通风阻力大的成品收集专用布袋收尘器与560 k W系统风机拆除,更换为Sepax-4500高效涡流选粉机,使选粉机子系统装机功率进一步下降了340 k W。同时,在实现"磨内磨细"的前提下,优化研磨体级配与装载量,管磨机主电机实际运行功率约降低700 k W左右;系统全部采用了变频调速节电技术。生产P·O42.5级水泥,系统产量保持250 t/h甚至更高(最高台时可达到270 t/h、比表面积≥380 m2/kg),粉磨系统电耗由38.1 k Wh/t降至25 k Wh/t。     

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。