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1.
冷却水系统中的污垢热阻及金属腐蚀速度的在线监测   总被引:3,自引:0,他引:3  
研究了冷却水系统中污垢热阻及腐蚀速度的在线监测方法;研制了能模拟冷却水流动和传热状态,并消除自腐蚀电位漂移和溶液IR降影响的冷却水污垢热阻及腐蚀速度在线监测装置;同时开发出相应的软件使整个测量和数据处理过程实现了计算机自动控制。实验结果表明:该装置能真实地在线反映换热器结垢和腐蚀变化情况。  相似文献   

2.
主循环冷却水系统腐蚀监测的重要意义,指出能够对设备作实时在线腐蚀监测的电化学以及计算机在腐蚀监控中的及循环冷却水系统腐蚀监测的2个主要发展方向,并搪塞了恒电量技术在这方面的应用前景。  相似文献   

3.
介绍一套循环冷却水腐蚀在线监测系统的原理、组成及其在热电厂的应用情况。该系统采用同种材料三电极体系,以热电厂实际使用的铜管制作传感器,利用电化学线性极化技术和交流阻抗技术测量铜管的年腐蚀速率。经过半年现场试用表明,该在线监测系统可以帮助现场工作人员及时了解凝汽器铜管的腐蚀结垢状况,为现场腐蚀结垢监测,进而指导生产提供有益信息。  相似文献   

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冷却水长期循环使用后,会出现腐蚀、结垢、微生物滋生等问题,影响系统的正常运行。通过对循环冷却水系统进行合理的水质处理,同时采用腐蚀在线监测技术对系统的腐蚀状况进行监测,保证了循环水系统安全、稳定运行。  相似文献   

5.
通过闪速炉循环冷却水系统在线清洗,解决了大型循环冷却水系统因结垢、腐蚀、微生物生长和沉积等引起的污垢生成和附着物影响正常运转的问题寻找出一种除垢范围广、除垢率高、能有效抑制清洗过程中水泥及多种金属材质混合系统腐蚀现象的在线清洗方法,并对在线清洗的意义及一般规律进行了总结和探讨  相似文献   

6.
闪速熔炼炉循环冷却水系统在线清洗技术   总被引:1,自引:0,他引:1  
郑东晟 《化学清洗》1997,13(5):15-19
通过闪速炉循环冷却水系统在线清洗,解决了大型循环冷却水系统因结垢,腐蚀、微生物生长和沉积等引起的污垢生成和附着物影响正常运转的问题,寻找出一种除垢范围广、除垢率高、能有效抑制清洗过程中水泥及多种金属材质混合系统腐蚀现象的在线清洗方法,并对在线清洗的意义及一般规律进行了总结和探讨。  相似文献   

7.
通过对某石化公司循环冷却水系统生产运行数据的分析,选取了对腐蚀速率影响较大的水质参数,借助神经网络良好的非线性能力,基于BP神经网络建立了腐蚀速率的预测模型.利用该模型对循环冷却水系统一定周期腐蚀速率的预测结果较好.  相似文献   

8.
工业循环冷却水腐蚀速率模型的研究   总被引:1,自引:0,他引:1  
循环冷却水在工业生产中占有很大比重,而腐蚀是循环冷却水系统中常见的水质故障,严重影响工业生产中设备的运行。通过对某石化公司水质数据的分析,选取对腐蚀速率影响较大的水质参数,凭借神经网络良好的非线性能力,基于NARX神经网络建立了腐蚀速率预测模型。利用该模型对循环冷却水系统腐蚀速率进行预测,结果较好,说明该模型可行,且具有良好的应用前景。  相似文献   

9.
环氧丙烷分厂对循环冷却水系统进行了改造,采用中水代替滦河作为循环水补水,并通过加药稳定水质,控制系统腐蚀和结垢。改造后循环冷却水系统金属腐蚀速率、污垢热阻值以及莱氏稳定常数RSI均符合《工业循环冷却水处理设计规范》GB50050-2007相关要求,实现了对中水的回收利用,达到了优化工艺的和降低成本的目的。  相似文献   

10.
潘维照  郑莉 《清洗世界》2006,22(9):13-16
介绍循环冷却水系统工艺和聚乙烯装置循环冷却水系统在线清洗方法,并讨论了在线清洗技术发展前景。  相似文献   

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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.  相似文献   

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14.
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.  相似文献   

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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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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