PCM在两端有钢塑转换接头的埋地钢质管道中的应用

非开挖检测技术对埋地管道的安全和经济运行具有重要的作用,而PCM外防腐层检测是埋地钢质管道非开挖检测的重要内容。本文介绍了PCM外防腐层检测的基本原理,并结合工程实例,介绍了两端有钢塑转换接头的埋地钢质管道的PCM检测方法以及埋地钢质管道在不具备导电连续性时的PCM检测技术,以便更好地发挥PCM在管道检测中的作用。     

在用工业埋地管道检验方法探讨

对于埋地敷设的压力管道,管道检验和安全性评价中不仅要考虑常规工业管道可能出现的损坏和失效形式,还要充分考虑到埋地管道所特有的管道外腐蚀、防腐层破损、老化等情况,即必须对管道埋地因素予以充分考虑。本次对工业埋地管道的检验在上海尚属首次,所以有必要对检验方法进行探讨。     

埋地钢质管道外防腐层的选择及运用

对气田长输管线而言,管道外防腐层是一个重点。从埋地钢质管道外防腐层的性能要求出发,介绍了外防腐层常见方案和运用原则,并结合四川气田进行分析,为进一步提高管道防腐性能提供新的思路。     

津华线埋地管道防腐涂层——三层PE

从天津港-华北石化原油管道工程管道防腐涂层的选择出发,介绍了埋地管道三层PE防腐涂层的特点,分析了埋地管道三层PE防腐涂层各部分的化学组成。指出埋地管道三层PE中,环氧粉末起主要防腐作用,聚乙烯层的作用是阻挡外界介质,胶黏剂是"桥梁",可以将熔接环氧粉末和聚乙烯有机连接在一起。最终,项目在特殊地段选择了三层PE防腐层,在一般地段选择了环氧粉末防腐层。     

管道电流测绘技术在地下燃气管道防腐层检测中的应用

城镇地下燃气管道的运行状况直接关乎城镇的安全。管道电流测绘技术可以在非开挖条件下对埋地管道的阴极保护有效性做出评价,有效地检测出埋地钢质管道外防腐层缺陷。在工程应用中,采用这种新颖的检测技术可以快速检测和定位某处地下燃气管道的外防腐层缺陷。     

埋地输油管道外防腐层检测及修复技术

为了确保埋地输油管道的安全、稳定运行,需要采用合理的技术手段对管道外防腐层破损进行准确地检测与完整修复。本文介绍了埋地输油管道外防腐层破损常用的检测方法和检测内容。并且,根据不同的实际情况,完成防腐层修复材料选择、管道表面处理以及修复施工与质量检测几方面的工作。其中,压敏胶热缩带不但可以改善自身的密封性与防水性,还有效地促进粘弹体防腐胶带的流动作用和浸润作用,因此粘弹体防腐胶带配合压敏胶热缩带将成为埋地输油管道防腐层修复的最佳选择。     

埋地油气管道防腐层检测与评价

埋地油气管道在施工及运行过程中,外防腐层不可避免会产生各种缺陷。为了保证油气管道安全稳定运行,必须定期对管道实施外检测以及时发现缺陷并加以安全评价。首先对埋地油气管道外防腐层缺陷检测内容进行了介绍,进一步分析了各种检测技术的工作原理及优缺点、防腐层分级评价和外腐蚀直接评价,最后阐述了外腐蚀检测的应用及存在的问题、相关技术标准以及发展趋势。指出应该不断发展完善现有管道防腐层检测技术,建立相应的分级评价体系,同时充分利用挖掘各类检测数据,深入拓展各种评价标准,建立适合国情的外腐蚀检测方法与评价体系。     

埋地管道外防腐及快速检测技术

介绍了埋地管道的主要腐蚀类型和保护措施,讨论了强制电流法保护系统在埋地管道防腐中的应用,管道防腐层的快速检测技术,并提出了在埋地管道防腐中应该注意的几个问题。     

埋地金属管道腐蚀机理及防护研究进展

腐蚀是困扰埋地金属管道的重要难题之一,更是造成管道事故的重要原因。文章综述了埋地金属管道的电化学腐蚀、微生物腐蚀、杂散电流腐蚀等主要机理,介绍了国内外利用缓蚀剂防腐、特殊涂层防腐、金属管道表面改性、阴极保护等几种主要的防护措施,并指出金属管道表面改性对于埋地金属管道防腐具有良好的作用,其应用前景非常广阔。     

三层PE防腐新技术在埋地管道中的应用

简要介绍先进的埋地管道防腐工艺——管道三层PE防腐,在埋地天然气管道、给排水管道中的应用,三层PE管道防腐工艺逐渐取代传统的管道防腐工艺。     

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。