FF现场总线安全技术在石化厂的应用

针对石化生产现场有易燃易爆化学介质的特殊生产环境,结合FF现场总线安全技术特点,介绍乙烯裂解装置凝液分离塔现场总线控制系统的设计方案.实践证明,该系统的投用提高了工业现场设备一级自动化和信息化的水平,在设备诊断和运行维护方面比传统控制系统缩短了工期并节省了费用.     

无线通讯技术在工业自动化领域中的应用

工业无线通信技术是继现场总线之后,工业控制领域的又一热点技术,是降低工业测控系统成本、扩展工业测控系统应用范围、推动自动化发展的关键技术。     

工业数据通信技术及其在赤天化的应用

现场总线是专为工业环境而设计的工业数据通信技术,赤天化纸业为了提高生产装置的自动化程度,增强集散控制,节省投资和维护成本,采用了这一技术。文章阐述了现场总线现有的标准概况、主要技术特点,重点介绍了该技术在赤天化纸业的应用场合,以及现场总线在施工、调试与运行过程中遇到的一些问题和处理情况,最后总结了这一技术在应用中取得的...     

炼油装置现场总线控制系统的实现及与MIS互连

介绍炼油装置生产过程中现场总线控制系统应用，以及控制系统总体设计、控制系统应用软件开发。采用动态网页技术实现了现场总线控制系统与炼油厂MIS系统的互连。     

ABB现场总线技术在水泥领域的应用

ABB推出工业IT（IndustrialIT）新控制系统平台后将工厂自动化技术水平提高到一个崭新的层次，该控制系统平台是完全基于现场总线系统，采用全开放一体化的全新控制器及操作员站作为硬件。软件采用控制领域最新技术和标准。目前在国内成功安装并运行在云南红塔滇西水泥项目，现将具体应用情况介绍如下。１．项目背景及技术要求云南红塔滇西水泥股份有限公司是云南红塔投资有限责任公司和云南省、大理州、大理市投资公司四方联合投资建设，由云南红塔投资有限责任公司控股的大型水泥生产企业，系云南省“八五”重点建设工程，配套服务于…     

Modbus现场总线在废水零排放项目中的设计与应用

现场总线技术是新一代分布式控制系统的核心技术,可通信连接生产现场的仪表、控制器等自动化装置;现场总线具有高精度,高扩展性,施工中可以降低安装成本,降低废水处理运行维护费用。结合内蒙某发电公司废水零排放项目,着重介绍了Modbus现场总线在总线控制系统(FCS)中的实际应用;重点阐述了Modbus总线网络结构与配置,对总线系统设计、调试中的部分细节进行说明;实际应用效果证明了现场总线控制技术在废水处理中的优越性。     

现场总线——第十一届多国仪器仪表展览会上的一道亮丽的风景

金秋时节 ,北京国际展览中心迎来了第十一届多国仪器仪表展览会。人们普遍关心的当前自动化领域热点内容之一———现场总线技术依旧是本届展览会的重头戏 ,囊括了当前流行的主要几种现场总线 ,从不同的角度展示了现场总线的技术、应用和发展趋势。就参展的主要现场总线Ｐｒｏｆｉｂｕｓ、ＦＦ、ＨＡＲＴ、ＬｏｎＷｏｒｋｓ中 ,当数Ｐｒｏｆｉｂｕｓ最大 ,ＦＦ和ＨＡＲＴ次之。现场总线的推广和应用 ,第一要求有符合协议的现场仪表 ,第二要求有控制系统的支持。从此次展览会看 ,各公司的过程控制装置几乎没有推出全新的现场总线控制系统 ,只…     

基于PLC的生产-教学两用型柔性电镀行车控制系统的设计

利用PLC、电机控制技术和现场总线技术,设计了一套柔性电镀行车控制系统。该系统的自动化程度高、可靠性好,能够适应柔性化电镀生产的需求,既可应用于自动化电镀生产线,也可作为应用实例用于PLC教学。     

浅谈现场总线技术的发展

论述了现场总线(FCS)的概念、组成和特点;通过对现场总线与常规集散系统(DCS)的比较,阐明了现场总线用于工业生产装置自动化控制的优点;简要介绍了国际自动化控制领域中较有影响的5项现场总线技术。     

基于工业以太网与现场总线的选煤厂综合自动化系统的设计

介绍了选煤厂基于工业以太网与现场总线技术的综合自动化系统的特点,与传统控制系统相比,该系统具有高实时性与安全性;同时,具有远程通讯接口,为实现矿井综合自动化奠定了基础。     

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。