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1.
水平管内油水乳状液流动特性研究   总被引:3,自引:0,他引:3  
对水平管内油包水型(W/O)和水包油型(O/W)油水乳状液进行了深入的实验研究。根据实验结果分析得出一个新的油水乳状液表观粘度的表达式,同时也得出一个新的油水乳状液相转变的判别式,并提出采用Re数和摩擦阻力系数的关联式计算摩擦阻力的方法,也得到判别油水乳状液为牛顿流体和非牛顿流体的方法  相似文献   

2.
油包水乳状液中水合物生长行为的差异会影响水合物的生长速率和生成量,为多相管道的安全运行和流动保障策略的制定带来挑战。本文结合国内外关于油包水乳状液中水合物生成行为的实验及理论研究成果,系统阐述了水合物生成实验研究方法及水合物生长过程常用量化指标,总结了油水体系中油相组成、含水率等因素对水合物生长行为的影响规律,分析了油包水乳状液中水合物的生长机理和量化模型的研究进展。文章指出,油包水乳状液中水合物生成方法和量化指标已较为完善,对影响因素和生长机理的认识正日趋深入。未来应进一步探明多组分复杂体系下的水合物生长动力学行为,并从微观角度深入对油水体系中水合物壳体结构及生长机理的理解,最终建立适用于实际多相管道的水合物生长速率模型。  相似文献   

3.
采用近红外稳定性分析仪研究了水包沥青质模拟油型乳状液的稳定性。考察了2种表面活性剂十二烷基硫酸钠(SDS)和十二烷基苯磺酸钠(SDBS)、沥青质浓度以及盐对乳状液稳定性的影响,探讨了油水界面张力及油珠表面的Zeta电位与乳状液稳定性的关系。结果表明,SDBS稳定的乳状液要比SDS的稳定;在所考察的条件范围内,沥青质浓度越高,乳状液越不稳定,盐能增强乳状液的稳定性。油水界面张力的降低有利于水包油乳状液的稳定,而Zeta电位可能不是影响乳状液稳定性的主要因素。  相似文献   

4.
邹小勇  赵如松  慕朝  房晓 《精细化工》2013,30(2):193-197
采用近红外稳定性分析仪研究了水包沥青质模拟油型乳状液的稳定性。考察了两种表面活性剂十二烷基硫酸钠(SDS)和十二烷基苯磺酸钠(SDBS)、沥青质质量浓度以及盐对乳状液稳定性的影响,探讨了油水界面张力及油珠表面的Zeta电位与乳状液稳定性的关系。结果表明,SDBS稳定的乳状液要比SDS稳定;在所考察的条件范围内,沥青质质量浓度越高,乳状液越不稳定,盐能增强乳状液的稳定性。油水界面张力的降低有利于水包油乳状液的稳定,而Zeta电位不是影响乳状液稳定性的主要因素。  相似文献   

5.
本文采用正交试验法,综合考虑10个影响因素,探究抗高温高密度柴油基油包水钻井液主要性能的影响因素,采用极差分析法处理实验数据,最终得出:影响乳状液稳定性的显著因素依次是辅乳加量、油水比、主乳润湿剂交互作用、主乳加量;影响流变性的共同显著因素是有机土加量、油水比;影响高温高压滤失性的显著因素依次是主乳加量、油水比、主乳润...  相似文献   

6.
管道运输是油品运输的重要方式之一,所以稠油乳状液在运输过程中的稳定性对运输效率起到决定性作用。不同类型的表面活性剂、界面张力、油水比、乳化温度、分散相粒径、化学添加剂、界面电荷等对稠油乳状液稳定性有着不同的影响,而影响水包油乳状液稳定性的主要因素是稠油乳状液分散性粒径的大小、界面张力和油水界面膜的性质。分析了平均粒径、界面张力和油水界面膜性质对水包油型稠油乳状液的稳定性影响,探究了使其稳定的机理和影响平均粒径、界面张力、油水界面膜性质的因素,并对水包油乳状液稳定性研究的发展前景进行展望。  相似文献   

7.
母铃燕  廖芮  朱泽城  叶杰 《广州化工》2020,48(17):55-56
目前国内大多数油田处在高含水开采阶段,易形成水包油型分散体系。这种油水分散体系中油滴的粒径分布对于原油的集输和分离都会产生一定程度的影响。本论文采用实验研究和理论分析相结合的方法,通过变量控制法配置多种水包油型乳状液,分析了含油率、搅拌转速、温度对油滴粒径分布的作用机理及其影响。研究结果为进一步进行多相混输管线的设计以及提高油水分离效率提供了理论支持。  相似文献   

8.
龚献  吴玉国  李小玲 《应用化工》2023,(4):1218-1224
根据国内外近年来对稠油乳状液稳定性的研究,综述了水包油型稠油乳状液稳定性的影响因素。介绍了水包油型稠油乳状液的形成以及油水界面膜性质,油水界面膜的强度在很大程度上决定了水包油型乳状液的稳定性。其次综合分析了稠油乳状液的动态稳定性与静态稳定性,含水率、乳状液粒径分布、乳化温度、界面张力、矿化度以及化学添加剂都对水包油型稠油乳状液的稳定性存在一定的影响。最后简介了基于聚焦光束反射测量仪的乳状液粒径分布测量,为研究稠油乳状液的动态稳定性提供一定的参考价值。  相似文献   

9.
分析了油水两相之间的界面张力大小,通过乳化实验测出乳状液的黏度变化和稳定时间,再借助显微镜观察水滴分散程度,最后得出对于酯类和磺酸盐类等大多数乳化剂,疏水基单烷基链越长,在油相中与油相之间交错的程度就会越复杂,配制出的乳状液性能越好;若乳化剂的疏水基团中存在不饱和双键,在空间上限制了烷基碳链在油相中的三维伸展,形成的乳状液乳化效果越差;若乳化剂的疏水基团中存在与烷基主链相同的支链,由于氢键的存在严重限制了疏水基在油相中的分散吸附,同时由于界面膜之间也会产生有一定的角度,使得界面膜的排列紧密程度变弱,导致乳状液性能变差。  相似文献   

10.
1 油田采出水的稳定机理及处理方法油田采出液中含有油包水(W/O)型和水包油(O/W)型两种不同的乳状液,是原油脱水和污水除油处理的主要对象。乳状液是热力学不稳定体系,纯的油水两相不能形成稳定乳状液,油田采出水之所以能稳定存在主要有两个方面的原因:开采和集输过程中受泵和管道机械外力搅拌作用,使得油水混合,生成了油水乳状液;  相似文献   

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12.
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.  相似文献   

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14.
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.  相似文献   

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17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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