涡街流量计在化工行业流量测量中的应用

结合化工行业流量仪表应用的实践,介绍了涡街流量计的测量原理,涡街流量计的选择和安装。提出了在化工行业的流量测量中使用涡街流量计的注意事项。     

涡街流量计在石油化工行业中的应用

涡街流量计是现代石油化工行业中测量流量的重要工具之一;简述了涡街流量计的测量原理和主要优点,提供了涡街流量计的选型、安装、使用和维护的建议;通过规范设计、合理选型、正确的安装和维护,让涡街流量计在石油化工行业中发挥更大的作用。     

涡街流量计在炼厂的应用

针对现代炼厂较少维护和低能耗的需求,涡街流量计在流量测量中应用的越来越广泛。本文比较了涡街流量计在国内外炼厂的应用现状,分析了涡街流量计在流量测量的优势,同时探讨了影响涡街流量计测量准确性的因素和对策。     

涡街流量计在UOP丙烷脱氢工艺装置的应用及维护

主要介绍涡街流量计的特点,并分析了涡街流量计的测量原理和测量方法,通过在UOP丙烷脱氢工艺装置的实际应用中的具体情况和运行维护中的经验,提出在涡街流量计安装、调试和维护上应注意的事项,最后对涡街流量计在生产运行过程中的常见故障进行了分析,并提出了故障处理方法。     

涡街流量计在氯碱行业中的应用

介绍了涡街流量计的工作原理、选型注意事项及安装要求,分析了其使用过程中的常见问题及相应对策,指出涡街流量计具有压力损失小、量程范围大、精度高、维护工作量小、成本低廉的特点,主要用于工业管道介质流体的流量测量。     

关于涡街流量计在蒸汽测量中的讨论

介绍涡街流量计的测量原理和特点,分析了在蒸汽测量中影响涡街流量计测量精度的因素,并提出了解决方法。     

YF100型旋涡流量计的应用

介绍涡街流量计在石油化工生产中应用,以上海横河YF100型旋涡流量计为例,简单介绍了涡街流量计的测量原理、特点、安装等问题,并在实际使用维护中提出几点注意事项以供参考。     

罗斯蒙特涡街流量计工作原理及常见故障处理

罗斯蒙特涡街流量计是化工厂中常用的流量测量仪器。结合实际操作中存在的问题和错误,从涡街流量计的工作原理出发,介绍了安装和使用过程中的注意事项。归纳了在现场应用中的多发故障和处理手段。本文对正确安装,使用和维护罗斯蒙特涡街流量计有一定的指导作用。     

差压式涡街质量流量计在蒸汽计量中的应用

鉴于稠油开采过程中的蒸汽吞吐及蒸汽驱技术,提出了对井口蒸汽质量流量计量的新方法。首先测量蒸汽通过涡街发生体后的差压,得到涡街频率,进而求出蒸汽的质量流量。这里主要介绍了用于蒸汽质量流量计量的压差式涡街流量计的原理,并对流量计的检测特点和实现的可行性进行了简单阐述。     

涡街流量计的技术改进研究进展

涡街流量计是根据涡街原理制备的测量气体和液体流量计量仪器,自上世纪八十年代以来被广泛使用,其技术也不断进步。本文就涡街流量计的旋涡发生体(阻流体)、检测元件(传感器)、前置放大器、滤波整形电路、D/A转换电路、输出接口电路等方面的技术特点和研究进展进行了综述,通过对涡街流量计原理的进一步的了解,期待有更好的改进思路,推动涡街流量计技术的进步。     

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.     

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。     

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.