浅谈管链输送机在聚酯装置中的应用

中石化洛阳分公司聚酯装置的主要原料精对苯二甲酸(PTA)现全部由化工车间提供,主要依靠气力输送系统由PTA大料仓向日料仓输送,耗氮量大,能耗高。本文结合装置实际运行情况对现有PTA输送系统进行了改造和优化,简要介绍了管链输送机在聚酯装置PTA输送系统中的应用,为解决因化工车间间歇式生产造成的聚酯及短纤维两套装置无法长周期平稳运行的问题提供了较好的解决方案,成功突破了聚酯装置原料输送瓶颈。     

尿素仓加装超高分子量聚乙烯板

尿素包装大料仓为矩形结构,四角尿素易结块,影响包装尿素质量,料仓清理时存在安全隐患,容易造成人员摔伤、砸伤等严重后果。在大料仓内壁加装超高分子量聚乙烯板,防止尿素板结在内壁上,消除结块现象。     

5000 m3 PTA料仓的整体优化设计

5000 m~3 PTA料仓是国内自行设计、制造的最大的焊接料仓。通过比较詹森和赖姆伯特两种计算方法的不同,验证了对于大直径料仓赖姆伯特方法更合理的结论。同时,在分析仓壳应力的基础上,通过理论推导和实际计算比较,对仓壳进行了整体的优化设计,从而节约材料,降低投资,提高安全性。     

浅议PTA料仓装车系统的设计

文章主要介绍了PTA料仓装车系统的的设计。通过对装车系统设计的一些设计原则进行了分析和探讨,以便于更好地掌握和改进PTA料仓装车系统的技术。     

浮动料仓在机立窑成球上的应用

为保证机立窑成球盘前生料仓连续供料,避免仓空,使料仓保持一定料位,我们于1976年将两个容量为10米~3圆锥料罐各自搁在三个φ140/20×240毫米弹簧上,(可利用铁路货车弹簧)料仓侧装上、下两个触头(JLXK1-311行程开关)当罐内物料至下限时,上触头动作使上料绞刀供料;罐内物料至上限时下触头动作,则绞刀停止供料。投产五年多来自控运行良好,安全可靠。     

塑料片材缓存料仓的设计

塑料回收清洗行业中片材缓存料仓经常遇到成拱现象,成拱架桥在料仓的设计中如何避免十分重要,现在设计料仓会常用到詹森(Janssen)公式,詹森(Janssen)公式是计算料仓存储静压力的基本公式,在设计料仓中得到广泛应用,但由于塑料片材在料仓的静态和动态运动状态不同,很多时候是两者交替存在,实际受力情况比较复杂,所有本文分析了料仓内物料流动特点,结拱的类型及成因,利用詹森(Janssen)公式理论计算,并结合实际设计生产实践经验,调整其理论长径比,料仓出料锥体斜度,设计出比较合理的料仓结构,为解决塑料行业片材缓存料仓的成拱架桥问题提出了参考方案。     

浅谈空气炮在煤仓防堵中的应用及选型

分析了物料在料仓内滞留起拱的原因及主要形式,论述了空气炮产品破拱助流的基本原理及操作控制方法,同时指出,对空气炮产品的选型,应根据料仓容积的大小及仓内各种物料的特性及结团程度选择相应的产品。     

料仓安设改流体的试验

一、改流体的应用在玻璃厂的粉料仓中,常会发生流动不畅、击穿和起拱的现象。料仓流,应该是全流的,如图1A所示。但实际上由于物料流动性的差异,将会出现的料流状态有: 1、流动性好,水分极少的物料、例如干长石粉,尽管在料仓中下料时不发生     

一种超细高分散橡胶助剂生产装置

正本实用新型公开了一种超细高分散橡胶助剂生产装置。该装置底座的顶部设有混料仓,混料仓的顶端开设有进料口,混料仓的内部横向穿插连接有搅拌杆,搅拌杆的外侧焊接有搅拌叶,底座的顶部内侧设有挤料仓。挤料仓的一端设有出料口,出料口的底部安装有切料仓,     

仓壳圆筒与仓壳锥体连接部分的受力分析

由于仓壳圆筒与仓壳锥体连接部分在几何上的不连续性,造成应力集中。通过对该部位的受力分析,得出对于大直径料仓,仓壳锥体圆周方向力Q为负值的结论,并且讨论了料仓设计标准中关于许用压缩应力的计算,给出了比较合理的选取。     

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。