建筑隔震橡胶支座四立柱平板硫化机加热方式优选

根据建筑隔震橡胶支座生产工艺的特殊性,对其硫化所用四立柱平板硫化机（简称平板硫化机）加热方式进行优选。从平板温升情况和温度极差以及平板硫化机制程稳定性和联程统一性4个方面分析,确定建筑隔震橡胶支座平板硫化机最佳的加热方式是导热油载体加热,以实现多台平板硫化机集中加热、联机运行。     

微波加热技术在橡胶硫化中的应用研究

本文针对橡胶微波加热硫化所存在的问题,应用ANSYS有限元分析软件,在分析比较了传统加热硫化和微波加热硫化胶料温升特点的基础上,提出了微波间歇加热的方法。根据硫化历程,设计了间歇加热的流程图,并模拟分析了微波间歇加热硫化胶料的温度变化趋势,模拟结果显示：采用微波间歇加热硫化能有效的解决微波连续加热硫化升温过快、焦烧时间不足、胶料不能很好充满模型,以及胶料内外温差逐渐加大的问题,对实际工程具有一定的实用价值。     

橡胶微波-传统联合加热硫化研究

运用ANSYS有限元分析软件,对圆波导模式下橡胶的微波-传统联合加热硫化过程进行仿真模拟,并与微波加热硫化过程进行对比。结果表明:仅采用微波加热方式,硫化胶内部温度较高,外部温度较低;而采用传统加热与微波加热相结合的方式,加热一定时间后,胶料内外能够同时被加热,胶料内部的温度梯度较小,内部温度分布较均匀。     

隔震橡胶支座的硫化工艺优化

采用TP700多路数据记录仪对隔震橡胶支座（以下简称支座）的硫化过程进行温度监测,利用阿累尼乌斯方程式计算支座各胶层的硫化效应、等效硫化时间以及硫化程度,并对支座的硫化工艺进行优化。支座的优化硫化条件为120 ℃×7 h,在该优化硫化条件下支座的硫化时间大幅缩短,硫化设备利用率提高,生产成本降低,产品性能满足设计要求。     

高效液相色谱法测定环保型丁苯橡胶及其凝聚水中防老剂EPDM含量

建立11.00R25轮胎硫化-传热耦合有限元模型,分别采用多维模型和混合定律模型模拟橡胶材料和橡胶-帘线复合材料,采用Isayev焦烧模型、经典内生热模型和混合动力学模型模拟橡胶的硫化特性,研究硫化介质温度对轮胎硫化特性的影响。结果表明,蒸汽温度对轮胎硫化影响较大,提出的分布区块法可以用来合理匹配蒸汽和过热水的温度。     

轮胎硫化温度场数值模拟

建立了硫化仿真有限元模型,其中胶料热物性参数和硫化动力学参数均为实测值,为最大可能考虑橡胶和帘线复合材料的结构特征,其导热系数采用正交各向异性模型,模型中加入了橡胶硫化过程中的反应热。三维轮胎模型的有限单元均采用六面体或者五面体单元,最大程度保证模型的计算精度。利用该仿真模型分析关键点仿真温度场和硫化程度场,历程曲线与实验值高度一致,硫化时间最大误差为4.8%,说明有限元模型能够高度反映实际硫化过程。     

建筑隔震橡胶支座硫化工艺研究

以LNR600建筑隔震橡胶支座为例,研究橡胶支座产品的硫化工艺。结果表明,按照总结出的橡胶支座硫化过程中胶料内部升温规律和硫化时间计算方法设计硫化工艺,采用该硫化工艺的产品性能达到技术要求,质量稳定可靠。     

硫化机电磁加热磁场分布的均匀性研究

研究橡胶硫化机电磁加热磁感应强度分布的均匀性。有限元模型分析表明:线圈感应加热装置加热过程中热板中心存在加热死区,通过在线圈中心增加铁芯(位于热板部分,为圆台形),提高了热板上的磁感应强度和温度场分布的均匀性,橡胶硫化质量提升。     

铅芯橡胶支座对桥梁横向抗震减碰影响分析

针对在地震作用下公路桥梁上部结构横向碰撞震害特征,通过铅芯橡胶支座来提升公路桥梁的横向抗震性能,减小主梁位移、主梁与挡块之间的碰撞力以及碰撞次数。以我国西北部一座典型公路桥梁为例,通过opensees有限元软件建立有限元全桥模型。采用非线性时程分析的方法探讨了铅芯橡胶支座对公路桥梁的横向减碰效果,采用铅芯橡胶支座比采用板式橡胶支座的模型主梁位移减少了22%,墩顶最大位移降低了64%,所产生的主梁与挡块碰撞力降低了24%和50%,碰撞次数也有所减少。结果表明:使用铅芯橡胶支座能够有效的减小主梁的位移、墩顶位移、碰撞力及碰撞次数,对横向抗震减碰能够起到很好的效果。     

火灾作用下钢筋混凝土基础隔震结构连续倒塌分析

为了得到火灾发生后基础隔震结构倒塌性能, 先进行了铅芯橡胶隔震支座在高温下力学性能的研究。通过ABAQUS有限元软件，建立了铅芯橡胶隔震支座和基础隔震框架的有限元模型并进行热力耦合分析。分析了火灾高温下橡胶隔震支座竖向刚度变化规律以及基础隔震框架结构的倒塌机制、应力状态、变形规律和塑性铰分布规律。结果表明：铅芯橡胶隔震支座的竖向刚度随受火时间的增长而逐渐降低，受火75 min时完全失去承载力；基础隔震框架不同位置支座受火时，框架呈现不同的应力、变形状态；边支座和内部双支座受火时，框架发生连续倒塌。     

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。