化工设备焊接中常见的缺陷及其控制措施

化工设备焊接中出现缺陷,轻则导致设备的损坏,重则危及人身安全。本文简要介绍了化工设备的焊接缺陷控制的意义,并深度分析了化工设备焊接中常见的焊缝外部、焊缝内部缺陷及其防止和修补策略。     

刍议化工设备安装中安全管理策略

化学工业在我国国民经济中占据的地位是毋庸置疑的,而化工生产在系统上通常是无数个设备相互连接组成的,工序的复杂和风险性以及技术都给化工设备的安装带来了一定的难度和隐患,因此做好化工设备安装中的安全可以说是化工安装中的重中之重,必须要加强化工设备在安装中的安全管理。本文主要从化工设备安装的特点入手,对化工设备安装中的安全管理策略进行分析。     

浅谈化工设备的安全检修

实现化工设备安全检修不仅要确保检修作业的安全,防止重大事故的发生,还应促进检修作业保质保量的完成,使化工设备投入运行后操作稳定、运转率高,杜绝事故和污染环境,为安全生产创造良好条件。文中叙述了化工设备安全检修中的危害因素,系统的分析了设备检修过程中所应采取的安全措施,对于今后化工设备安全检修工作具有借鉴作用。     

化工设备安全管理的策略研究

现阶段伴随着我国科技水平的不断提高,目前化工设备安全管理已经成为化工企业中生产的重要保证。近年来,化工产品的用途越来越广,已经运用到了各个经济领域,因此化工设备安全管理的问题备受关注,同时化工设备安全管理在保障设备和人员安全的前提下,还必须进行合理的安装,从而保障设备达到最佳的使用状态。主要对化工设备安全管理及其重要性进行了概述与分析,对目前化工设备安全管理面临的现状以及提升化工设备安全管理的策略进行了探讨。     

换热管与管板封口焊焊缝密封性试验改进

介绍了压水堆核岛设备中一回路主系统Ⅰ级设备蒸汽发生器(SG)换热管与管板封口焊焊缝密封性试验,其对重要化工设备的密封性检测具有借鉴作用。     

化工设备安装中焊接质量控制研究

化工设备的质量是保证化工生产安全进行的基本条件,而焊接又是化工设备安装质量的重要保障,由此可见,化工设备的焊接工艺是非常重要的,直接影响着化工设备的质量安全,本文笔者就对化工设备安装中如何控制焊接质量进行必要的研究,旨在提高化工设备的质量,保证化工生产的安全进行。     

化工设备安装中的焊接质量控制研究

焊接是化工设备安装中的常用技术之一,焊接质量受到焊接工艺、外界空气温湿度、焊接方式、焊条类型等多种因素的影响,若焊缝出现质量缺陷,将降低化工设备的安装质量,进而影响化工设备后续运行的安全性、稳定性、可靠性与持续性。基于此,文章简要论述化工设备安装中常用的焊接技术类型,分析化工设备焊接前需要做足的准备工作,分析焊接工作中的质量控制措施,并探究化工设备焊接后的质量检测方法,旨在为化工设备的安装提供思路。     

化工机械技术在化工设备中的应用

化工设备是支持化工生产的重要设备。化工设备是否可以安全、稳定运行直接影响着最终化工生产的效果。随着化工生产的规模逐渐的增大,化工设备的使用越来越频繁,一些问题也逐渐的涌现出来。化工机械技术应用到化工设备中可以充分的满足当今时代化工设备安全、稳定运行的要求。因此,为了更好地促进化工生产,化工企业要重视化工机械技术在化工设备中的应用。本文主要对化工机械技术在化工设备的应用进行了深入的研究,首先分析了化工机械技术的重要地位以及作用,然后提出了化工设备中机械技术的具体应用策略。     

分析化工设备安装中焊接技术的质量控制

在化工行业发展过程中,化工设备安装质量直接关系着化工设备的正常运转和生产安全,必须要加强焊接质量控制。对化工设备安装前、安装过程中和安装后焊接质量控制进行探究,旨在全面提升焊接质量,提升化工设备安装的精准性。     

化工设备的安装管理探析

化工设备的安装与普通设备安装相比具有更强的不可确定性，更易受到外界各种因素的影响，如果安装过程中管理工作不到位，将会对整个企业造成重大损失。化工设备安装、系统装配以及零部件组装等都是需要加强管理的注意点。本文分析了化工设备安全管理的注意事项以及要点。     

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。