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1.
四氢呋喃-水-钾盐体系相平衡数据的测定和关联   总被引:1,自引:0,他引:1  
测定了四氢呋喃–水–氟化钾及四氢呋喃–水–碳酸钾体系在25℃时高盐浓度下的液–液相平衡数据,用Pitzer理论和NRTL方程对相平衡数据进行了关联计算,计算值与实验值吻合较好.  相似文献   

2.
针对乙醇水溶液萃取丁醇+辛烷+壬烷混合物后的萃取相中残留的辛烷和壬烷,提出了使用十四烷作为反萃剂对萃取相进行反萃,测定了常压、298.15K下乙醇+丁醇+辛烷或壬烷+水+十四烷五元体系和乙醇+丁醇+辛烷+壬烷+水+十四烷六元体系的液液相平衡数据.使用Othmer-Tobias方程检验了液液相平衡数据的准确性,线性相关系...  相似文献   

3.
采用气相色谱法测定了环己酮-水-氟化钾、环己酮-水-碳酸钾体系在25℃时的液液相平衡数据,相平衡数据表明产生的环己酮相中含有可以忽略的盐、水相中含有可以忽略的环己酮,因此采用氟化钾或碳酸钾可以有效地分离环己酮-水体系。分别采用Pitzer和NRTL方程计算水相和环己酮相中水的活度,将二者结合对液液相平衡进行了数学计算,计算值与实验值吻合较好,说明所选热力学模型对环己酮-水-氟化钾及环己酮-水-碳酸钾体系具有较好的计算精度,为采用氟化钾或碳酸钾分离环己酮-水体系提供了基础数据和设计依据。  相似文献   

4.
测定了丁酮 水 氟化钾及丁酮 水 碳酸钾体系在 30℃时的液液相平衡数据 ,用Pitzer理论和Wilson方程对相平衡数据进行了关联计算 ,计算值与实验值符合良好 ,为工业上用盐分离丁酮 水体系提供了基础数据  相似文献   

5.
许文友  袁希钢 《化学工程》2004,32(1):65-68,76
实验测定了正丙醇 水 氟化钾、异丙醇 水 氟化钾、正丙醇 水 碳酸钾、异丙醇 水 碳酸钾体系在25℃时的液液相平衡数据,当水相中氟化钾或碳酸钾浓度较高时产生的正丙醇或异丙醇富集相中含有可以忽略的盐,水富集相中含有可以忽略的正丙醇或异丙醇,因此用氟化钾或碳酸钾可以成功地分离正丙醇 水或异丙醇 水体系。采用Pitzer方程计算富水相中水的活度,用NRTL方程计算富正丙醇或异丙醇相中水的活度,将二者结合对液液相平衡数据进行理论计算。结果表明计算值与实验值符合良好,为工业上用钾盐分离正丙醇 水或异丙醇 水体系提供了数据和模型。  相似文献   

6.
为解决在液液萃取或三相精馏过程的设计和操作中面临的液液相或汽液相平衡问题,论述了完全互溶二元物系和部分互溶二元物系UNIQUAC模型参数的估算原理;介绍了运用Matlab优化工具箱函数进行参数估值的方法;以丙酮苯的等温汽液平衡数据、乙醇正己烷的等压汽液平衡数据、醋酸甲酯水的相互溶解度数据为例,估算了各二元对的UNIQUAC模型参数,结果表明,用Matlab优化函数计算的结果与文献值十分吻合。  相似文献   

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为了给溶剂萃取分离正己烷–异丙醇混合物的过程设计和流程模拟计算提供基础数据,以二甲亚砜、1,4-丁二醇、1,2-丙二醇、乙腈、糠醛和N,N-二甲基甲酰胺为萃取剂,测定了30℃下萃取分离正己烷–异丙醇混合物的液液相平衡数据,并利用分离因子评价不同萃取剂的萃取分离性能。根据Hand方程对实验数据进行一致性和可靠性检验,拟合方程的相关系数都在0.98以上。随后,采用Aspen Plus软件选取NRTL活度系数模型对相平衡数据进行关联,得到相应的二元交互作用参数,并以此计算相应的相平衡组成。结果显示,计算值和实验值的均方根偏差小于1.0%,表明NRTL模型能够准确描述三元体系的液液相平衡。  相似文献   

8.
叔丁醇-水-钾盐体系液液相平衡的研究   总被引:1,自引:0,他引:1  
将氮化钾或碳酸钾加入到叔丁醇—水体系中时,可产生水富集相和叔丁醉富集相。实验测定了叔丁醇-水—氮化钾、叔丁醇—水—碳酸钾体系在25℃时的液液相平衡数据。结果表明,当水相中氮化钾或碳酸钾浓度较高时产生的叔丁醇富集相中含有可以忽略的盐,水富集相中含有可以忽略的叔丁醇,因此用氮化钾或碳酸钾可以成功地分离叔丁醇-水体系。采用Pitzer方程计算富水相中水的活度,用Wilson、NRTL或UNIQUAC方程计算富有机相中水的活度,将二者结合对液液相平衡数据进行理论计算,计算值与实验值符合较好。  相似文献   

9.
二氧化碳与乙醇和异丙醇的二元汽液平衡   总被引:1,自引:1,他引:1  
应用汽液双循环高压相平衡装置,测定了二氧化碳-乙醇和二氧化碳-异丙醇二元混合物分别在303.15K,310.15K和329.15K,压力范围为1.78~10.04MPa下的汽液相平衡数据。用DDLC-SRK方程关联两个二元体系的汽液相平衡数据,计算值与实验值吻合良好。  相似文献   

10.
李柏春  王琮  黄岩  张文林 《化工进展》2013,32(10):2292-2296
采用汽液双循环平衡釜,在常压(101.3 kPa)下测定了丙酮-丙酮连氮二元组分物系以及部分丙酮-水-丙酮连氮三元组分物系的汽液平衡数据。实验数据经Herington面积积分法检验符合热力学一致性。通过化工过程模拟软件,分别采用Wilson、NRTL、UNIQUAC 活度系数模型对丙酮-丙酮连氮二元组分物系实验数据进行关联得到模型参数。并对汽液平衡的计算值与实验值进行比较,3种模型都吻合良好,其中由NRTL方程关联得到的计算结果最为适合,平均温度偏差和汽相组成偏差分别为0.0639 K和0.0048。从三元汽液相平衡数据中拟合出了丙酮-丙酮连氮、丙酮-水、水-丙酮连氮之间的NRTL方程相互作用参数。为验证数据及其二元相互作用参数的可靠性,利用关联出的丙酮-丙酮连氮模型参数计算出汽相组成与丙酮-丙酮连氮的二元数据比较,二者符合较好。实验和关联的结果为精馏分离丙酮-水-丙酮连氮汽液平衡体系提供了一定的基础数据。  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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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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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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