复混肥结块原因及预防措施

阐述了复混肥结块的机理,分析了影响复混肥结块的主要因素,提出了防结块措施。     

尿素涂层液在复混肥防结块中的应用

复混肥结块长期影响复混肥产品的质量和施用。随着中、高浓度复混肥的发展和推广 ,结块问题显得更加突出。笔者根据多年的生产实践 ,介绍尿素涂层液在复混肥防结块中的应用。1　复混肥的结块与对策按照国家复混肥标准 GB1 50 63- 94,产品品位不同 ,允许其含水在 2 %～ 5%的范围 ,这些水分是肥料盐的饱和溶液。结块与包装温度、产品颗粒度、带粉状况和堆叠高度等有着密切关系 ,应采取下列措施加以解决。( 1 )　降低产品含水量　在生产中 ,一些厂家把低浓度二元复混肥的含水量控制在 2 % ,中、高浓度复混肥则控制在 1 .5%以下 ,从而降低产品…     

25%和34%复混肥改良防结块剂试验初报

分析肥料的结块和防结块机理及复混肥结块因素,通过添加烷基芳基磺酸盐、脂肪酸铵盐、高分子聚合物和胺类等多种成分研制改良防结块剂。将改良防结块剂应用于25%和34%复混肥,通过吸湿率和防结块效果试验,表明其吸湿率较低,防结块率高,利于长期贮存。     

复混肥料防结块剂的研究与应用

阐述了影响复混肥料结块的因素、复混肥防结块剂的类型及应用情况。针对现有防结块剂存在的问题,论述了新型和缓释型防结块剂的研究开发现状,讨论了复混肥防结块剂的发展方向。     

高氮复混肥防结块剂的使用小结

介绍适用于含氮25%～28%高氮复混肥防结块剂的防结块机理、使用情况及防结块效果。     

复混肥料的结块因素分析及防结块技术

分析了复混肥料结块的因素 ,以及我公司为解决复混肥料的结块问题所采取的措施 ,主要介绍了两种防结块剂在 3万t/a复混肥装置上的应用     

复混肥防结块技术的研究和开发

阐述了复混肥结块的3大机理,影响结块的主要因素及作用原理,分析了防结块的方法,其中最常用的方法是向复混肥中添加防结块剂.分析了防结块剂的作用机理、主要类型、添加方式及防结块性能的评价方式.评述了国内外防结块剂的发展状况,并讨论了复混肥防结块剂及防结块技术的研究方向和发展趋势.     

内外防结块剂共同使用的防结块效果

大多数复混肥生产厂家采取扑粉、包膜或包膜加扑粉的方式处理复混肥产品的结块问题。其中包膜处理工艺使用较多 ,复混肥也因不同的包膜处理 ,防结块效果有的 2～ 3个月 ,好的达到 5～ 6个月 ,但防结块效果存在一个明显的趋势 ,即随着时间的推移 ,防结块效果越来越差 ,结块趋势越来越严重。复混肥料在贮存中含水量和吸湿对其结块影响最大。为了减轻复混肥的结块程度 ,应设法提高其临界相对湿度(CRH值 )。有些厂生产复混肥时 ,与基础肥料一起加入一定量的内防结块剂 ,用来提高复混肥料的 CRH值 ,减缓其吸湿速率。使用的内防结块剂有机物有…     

复混肥结块与防结块剂的应用

合肥四方磷肥有限责任公司有1套5万t/a复混肥装置,其高浓度复肥产品存在一定的结块现象。分析影响复混肥结块的因素,对原防结块剂装置进行了技术改造,选用花王复混肥防结块剂,取得了满意的效果。花王防结块剂的化学组成是阴离子表面活性剂和阳离子表面活性剂的混合物,主要是通过减少肥料颗粒间结合力和减少吸湿—干燥反复过程来防止肥料结块。通过调研、试验及论证,我公司决定对原防结块剂装置进行技改,现将选用花王复混肥防结块剂的应用情况介绍如下。1　工艺流程采用蒸汽加热、伴热与保温。将花王固体防结块剂直接加热熔化,流入保温贮…     

复混肥水溶性防结块剂的制备与性能测试

通过分析复混肥结块的影响因素和表面活性剂-聚合物复配物的防结块机理,开发出一种水溶性复混肥防结块产品。介绍了产品的制备过程及其所具有的特性,并通过吸湿率测定、加速结块、模拟堆压和N溶出率测定等实验完成产品防结块及缓释性能的测定。试验结果显示,在加速结块和模拟堆压条件下防结块率达到90%以上;4 h时N溶出率为85.2%,证明产品的具有较好的防结块性能和一定的缓释性能。     

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。