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1.
测定了柴油机油模拟油/蒸馏水体系的界面张力、界面剪切粘度和乳状液稳定性。结果表明,含有添加剂T154的柴油机油模拟油与蒸馏水间的界面张力明显低于无添加剂的体系的界面张力,界面剪切粘度增加,乳状液特性值比模拟油/蒸馏水体系稍大,乳状液稳定性增加;添加剂T109却使模拟油与蒸馏水体系的界面张力增大,界面剪切粘度降低,乳状液特性值比模拟油/蒸馏水体系小,乳状液稳定性降低,有一定的破乳作用。  相似文献   

2.
新滩稠油O/W乳状液是由含水较高的W/O乳状液直接转相形成的,利用微观摄像技术对其微观结构进行了研究。研究发现,乳状液中含有一定量的W/O/W液滴,其数量的多少与乳化剂浓度和含水量的大小有一定关系。液滴的形状大多数是等轴球形,既有液滴单个的乳滴存在,又有相互接触的乳滴簇存在,有乳滴形成乳滴簇的过程,也有乳滴簇分离的过程。乳滴大小分布模式基本相似,但对于具体的乳状液来说还是有差别。乳滴的大小分布受乳化剂浓度、油水性质含水量和放置时间等的影响。乳状液随时间表现出的性质主要是其微观结构变化的结果。液滴的大小分布情况和存在方式,在一定程度上影响乳状液的稳定性和流变行为。  相似文献   

3.
随着乳状液频繁的应用于提高采收率过程中,乳状液驱替效率与其影响因素之间的关系越来越重要。乳状液不仅可以作为堵剂,提高波及面积,改善注水剖面;也可以作为驱油剂提高非均质油层的驱油效率。在乳状液驱替提高采收率研究中,乳状液的驱油效率受到很多影响因素的制约,与乳滴本身大小、空隙结构以及外驱动压力梯度、界面张力都有非常密切的关系。通过岩心驱替实验,发现乳状液在驱替过程中,随着乳滴增大和界面张力增大,渗透率下降;随着驱动压力增大,渗透率升高。  相似文献   

4.
用界面张力仪、表面黏弹性仪和Zeta电位仪研究了胜利埕东油田聚合物强化泡沫复合驱中聚合物和/或发泡剂质量浓度对油水界面特性及乳状液稳定性的影响.结果表明,随聚合物质量浓度增加,模拟水与原油模拟油间油水界面张力、界面剪切黏度和油滴表面的Zeta电位绝对值增大;而随发泡剂质量浓度增加,模拟水与原油模拟油间的界面张力降低,界面剪切黏度有所增加,但变化幅度很小,油滴表面的Zeta电位绝对值增大;原油模拟油与含聚合物和发泡剂的模拟水间所形成的W/O乳状液稳定性随聚合物和/或发泡剂质量浓度增加而增强.  相似文献   

5.
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   

6.
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   

7.
环境温度会对乳状液使用性能产生重要影响。本文针对实验室自制乳化剂构筑的油包水乳状液体系,明确油包水乳状液稳定性随静置时间的增长而变差;在静置温度≤40℃范围内,油包水乳状液稳定性随温度的升高变化不大,在静置温度>40℃范围内,油包水乳状液稳定性随温度的升高而下降,在静置温度达到90℃时会导致油包水乳状液破乳,但在选定温度范围内不会破坏体系内组分化学结构,经二次高速搅拌可重构稳定的油包水乳状液。  相似文献   

8.
阳离子对稠油乳状液破乳的影响   总被引:1,自引:0,他引:1  
以稠油为研究对象,考察了不同阳离子对稠油乳状液破乳效果的影响。测定了不同种类及含量的无机盐对稠油乳状液脱水率、黏度及油一水界面张力的影响。结果表明:二价离子ca^2+,Mg^2+可以促进破乳,一价离子Na^2+对乳状液破乳影响不大,心对破乳有一定抑制作用。阳离子促进乳状液破乳能力由大到小依次为:Mg^2+ca^2+,Na^2+,K^2+。稠油乳液黏度、界面张力对破乳影响无规律性。  相似文献   

9.
王玉江 《应用化工》2010,39(3):318-322,328
用界面张力仪、表面粘弹性仪和Zeta电位仪测定了胜利坨11南原油模拟油与采出水间的界面特性,研究了聚合物、交联剂及弱凝胶对这些界面特性及乳状液稳定性的影响。结果表明,模拟水中加入聚合物、弱凝胶后,模拟水与原油模拟油间的界面张力、界面剪切粘度和油滴表面的Zeta电位绝对值增加,原油与含聚合物和弱凝胶的模拟水间所形成的W/O和O/W乳状液稳定性随聚合物、弱凝胶浓度增加而增强;交联剂对原油模拟油与模拟水间的界面性质及所形成的乳状液稳定性影响很小。  相似文献   

10.
原油组分对采出水乳状液稳定性的影响   总被引:1,自引:0,他引:1  
采用界面张力仪、表面粘弹性仪和浊度仪,研究了原油组分对桩西采出水乳状液稳定性的影响.结果表明,当各组分在模拟油中的浓度相同时,沥青质的界面张力最小,蜡组分的最大,胶质的居中;在相同的剪切速率下,沥青质的界面剪切粘度最大,蜡组分的最小,胶质的居中.原油组分浓度增加,组分模拟油油水界面张力减小,界面剪切粘度增加,乳状液稳定性增强.分离组分模拟油乳状液稳定性的强弱顺序依次为:沥青质组分>胶质>蜡组分.  相似文献   

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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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