等密度喷洒旋转造粒喷头及其新进展

指出凭估定设计的底部供料均布喷孔的传统喷头所存在的固有缺点，如喷洒密度呈尖峰状分布及部分喷洒线交错等。作者根据喷头及喷洒状况设计等密度喷头，并给出了各种规格喷头的喷洒密度分布曲线．德州化肥厂１３万吨／年尿素使用此种喷头喷洒密度分布曲线平坦，粒径在１．５～２．５ｍｍ的接近９０％，颗粒强度也很好．     

等密度喷酒旋转造粒喷头及其新进展

指出凭估定设计的底部件料均布喷孔的传统喷头所存在的固有缺点，如喷洒密度呈尖峰状分布及部分喷洒线交错等，作者根据喷头及喷洒状况设计等密度喷头，并给出了各种规格喷头的喷洒密度分布曲线。德州化肥厂１３万吨／年尿素使用此种喷头洒密度分布曲线平坦，粒径在１．５～２．５ｍｍ的接近９０％，颗粒强度也很好。     

等密度喷洒旋转造粒喷头的新进展

等密度喷洒旋转造粒喷头的新进展中国五环化学工程公司（化四院）对造粒喷头提出合理的“等重量密度喷洒设计法”，可对多种能力、塔径和粒径条件作出准确合理的设计。与传统喷头根本差别在于。喷头内部设有微分横向分料盘就地供料，锥体上喷孔呈特异分算其排距与孔距均各...     

大型化肥厂尿素造粒测定报告

调查与测定了６个大化肥厂造粒和储运包装的运行情况。结果表明：锥形与斜孔喷头所造粒的合格率均在９８％以上，横向喷洒密度分布均呈突出的驼峰状，斜孔喷头更为突出，两种喷头颗粒分布均呈现喷洒带外区为大颗粒，斜孔喷头所造颗粒在储运包装过程易粉化，锥形喷头塔顶排尘较大。针对所存在的问题提出改进建议     

国内动态

旋转造粒喷头新设计中国武汉化工工程公司设计开发的等重量密度喷洒技术的塔式化肥造粒旋转喷头,在国内大、中、小型化肥厂试验,取得理想效果。该公司已向国外有关部门提交了发明专利申请。这种新设计的旋转造粒喷头,喷孔喷出的每个颗粒都按照预定的空间位置降落,能保证喷洒线无交错,因而颗粒不会发生碰撞长大而使造粒塔底粘结。此外,由于喷洒带内可达到     

TX型造粒喷头的性能剖析及应用

美国ＴＸ型造粒喷头以其结构简单、维修方便、产品质量优良等特点，在我国许多大化肥厂尿素装置使用。但是在使用一段时间后，不同程度地出现一些问题，主要表现在颗粒不够均匀、强度不足。通过实际测试比较及理论分析，说明改变喷头转速及喷头孔径对产品的影响。１　ＴＸ型喷头性能参数ＴＸ型喷头性能参数：喷头孔数６２６４个；排数７２排；每排孔数８７个；能力８５（ｍａｘ），７３（ｎｏｒ），４３（ｍｉｎ）ｔ／ｈ；转速３２０（ｍａｘ），２８０（ｎｏｒ），２００（ｍｉｎ）ｒ／ｍｉｎ；１～２－４ｍｍ粒径≥９７％；造粒塔内径２２…     

新型尿素喷头化解造粒塔难题

由浙江省温岭市环球造粒喷射设备有限公司研制的ZL-H新型缓冲内旋转等压尿素造粒喷头,经在山东瑞星集团、山东寿光联盟化工有限公司等氮肥企业应用后表明：该喷头成功化解了φ9m塔造粒产能扩大与颗粒增大后出现的粘塔底、出料温度高、粉尘增多等影响尿素外观质量的难题。     

斜孔尿素造粒喷头的应用

一、概述当前,尿素造粒一般均采用直孔喷头。这种喷头由于喷洒分布不均,集中在塔内某一环带上,降低了塔的利用率。出现造粒状况不良,尿素出塔温度高,粘下料漏斗,排     

基于正交试验法对干法造粒颗粒大小影响因素的分析

采用正交试验设计方法,分析了陶瓷粉料干法造粒机喷水时的转速、造粒时的延时转速以及喷头类型这三个因素对干法造粒中颗粒大小的影响.通过直观分析、方差分析和贡献率分析,结果一致表明,各因素对陶瓷粉料干法造粒颗粒大小影响显著性的大小顺序为:喷头类型＞喷水转速＞造粒延时转速；最佳因素组合方案为A1B1C1,即造粒机喷水时转速为60r/min、造粒机造粒时转速为60r/min、喷头类型为喷头1,按此工艺可得到较高的成品率,且该组合经济实用,工艺可行.     

旋转式造粒喷头制造技术改进及应用

针对旋转式造粒喷头在使用过程中喷洒不均匀、焊缝易开裂、使用寿命低等问题，对设备结构、工作原理、原加工方案开展研究，通过比较分析直孔与斜孔喷头的优缺点，并结合使用效果，确定了斜孔喷头的研究方向。通过理论推导与计算，确定了最优斜孔角度，有效保证了造粒喷头的工作效率与喷粒质量。通过调整加工方案，采用喷筒双面自动焊接和下盖水切割分体的工艺方法，保证了造粒喷头的各项指标，提高了使用寿命。最终改进型喷头通过工程实践证明了可行性，并在国内多家化工厂内得到了推广应用，逐步取代进口技术，达到了尿素生产关键设备、部件国产化的目标。     

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.