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1.
盐酸中原儿茶醛在钢表面的吸附及缓蚀作用   总被引:1,自引:0,他引:1  
用失重法和动电位极化曲线法研究了在1.0mol/L HCl中20~50℃原儿茶醛(3,4-二羟基苯甲醛)在冷轧钢表面上的吸附及缓蚀作用.结果表明:原儿茶醛具有中等程度的缓蚀作用,为混合抑制型缓蚀剂,缓蚀率随原儿茶醛的浓度增加而增大,但随温度的增加而减小;原儿茶醛在钢表面的吸附符合Freundlich吸附模型.通过吸附理论和动力学Arrhenius公式求出了相应的吸附热力学参数(吸附自由能ΔG°,吸附热ΔH°,吸附熵ΔS°)和动力学参数表观活化能Ea,并根据这些参数详细讨论了缓蚀作用机理.  相似文献   

2.
溴化十六烷基吡啶在HCl中对冷轧钢的缓蚀作用   总被引:1,自引:0,他引:1  
邓书端  李向红  付惠 《云南化工》2010,37(2):7-9,13
用失重法研究了在1.0 mol/L HCl中20~50℃时溴化十六烷基吡啶(HDPB)在冷轧钢表面上的吸附及缓蚀作用。结果表明,HDPB对钢具有良好的缓蚀作用,缓蚀率随缓蚀剂浓度和温度的增加而增大;HDPB在钢表面的吸附符合Langmuir吸附模型。求出了相应的吸附热力学参数(吸附自由能ΔG0,吸附焓ΔH0,吸附熵ΔS0),并根据这些参数详细讨论了缓蚀作用机理。  相似文献   

3.
盐酸中硝氮黄染料在钢表面的吸附及缓蚀作用   总被引:1,自引:1,他引:0  
用失重法研究了在1.0 mol/L HCl中染料类化合物硝氮黄(NY)在冷轧钢表面上的吸附及缓蚀作用。结果表明,NY对冷轧钢具有中等程度的缓蚀作用,缓蚀率随NY的浓度增加而增大,而随温度的增加而减小;NY在钢表面的吸附符合Temkin吸附模型。通过吸附理论求出了相应的吸附热力学参数(吸附自由能ΔG0,吸附热ΔH0,吸附熵ΔS0),并根据这些参数详细讨论了吸附和缓蚀作用机理。  相似文献   

4.
中性红在盐酸溶液中对冷轧钢的缓蚀作用   总被引:1,自引:0,他引:1  
用失重法和动电位极化曲线法研究了酸碱指示剂中性红对冷轧钢在1.0~8.0 mol/LHCl溶液中的缓蚀作用.结果表明:中性红对冷轧钢在1.0 moL/L HCl溶液中具有良好的缓蚀作用,为混合抑制型缓蚀剂,且在钢表面的吸附符合校正的Langmuir吸附等温式,缓蚀率随缓蚀剂浓度的增加而增大,但随温度和盐酸浓度的增加而减小.通过吸附理论求出了相应的吸附热力学(吸附自由能△G°,吸附热△H°,吸附熵△S°)和动力学参数(腐蚀速度常数k,腐蚀动力学常数B),并根据这些参数讨论了缓蚀作用机理.  相似文献   

5.
用失重法研究了在1.0mol/L H2SO4中20-50℃聚乙二醇20000(PEG-20000)在冷轧钢表面上的吸附及缓蚀作用。结果表明:PEG-20000对钢具有良好的缓蚀作用,缓蚀率随缓蚀剂浓度的增加而增大;但随温度的增加而增大。PEG-20000在钢表面的吸附符合Langmuir吸附模型。通过吸附热力学和动力学公式分别求出了相应的吸附热力学参数(吸附自由能ΔG,°吸附焓ΔH°,吸附熵ΔS°)和动力学参数表观活化能Ea,并根据这些吸附参数详细讨论了缓蚀作用机理。  相似文献   

6.
H_2SO_4中聚乙二醇20000在钢表面的吸附及缓蚀作用   总被引:1,自引:0,他引:1  
用失重法研究了在1.0mol/L H2SO4中20~50℃聚乙二醇20000(PEG-20000)在冷轧钢表面上的吸附及缓蚀作用。结果表明:PEG-20000对钢具有良好的缓蚀作用,缓蚀率随缓蚀剂浓度的增加而增大;但随温度的增加而增大。PEG-20000在钢表面的吸附符合Langmuir吸附模型。通过吸附热力学和动力学公式分别求出了相应的吸附热力学参数(吸附自由能ΔG,°吸附焓ΔH°,吸附熵ΔS°)和动力学参数表观活化能Ea,并根据这些吸附参数详细讨论了缓蚀作用机理。  相似文献   

7.
邓书端  李向红  付惠 《清洗世界》2009,25(8):9-13,30
用失重法及电化学法研究了阴离子表面活性剂油酸钠(SO)对冷轧钢在3.0 mol/L H3PO4溶液中的缓蚀作用.结果表明:油酸钠对冷轧钢具有良好的缓蚀作用,为阴极抑制型缓蚀剂,缓蚀率随油酸钠的浓度增加而增大,而随温度的升高而减小;油酸钠在钢表面的吸附在30℃和40℃时符合校正的Langmuir吸附模型,50℃和60℃时则符合Freundlich吸附模型.通过吸附理论和化学热力学基本公式求出了相应的吸附热力学参数(吸附自由能ΔG°, 吸附热ΔH°, 吸附熵ΔS°),并根据这些参数详细讨论了缓蚀作用机理.  相似文献   

8.
盐酸介质中吐温-60对冷轧钢的缓蚀作用机理   总被引:5,自引:0,他引:5       下载免费PDF全文
木冠南  李向红  屈庆  周俊 《化工学报》2005,56(11):2150-2156
用失重法及电化学法研究了非离子表面活性剂吐温-60对冷轧钢在1.0~8.0 mol•L-1盐酸溶液中的缓蚀作用. 结果表明:吐温-60对冷轧钢在1.0 mol•L-1盐酸溶液中具有良好的缓蚀作用,且其在钢表面的吸附符合Langmuir吸附模型. 缓蚀率随缓蚀剂浓度的增加而增大,但随盐酸浓度和温度的增加而减小. 动电位极化曲线表明,吐温-60为混合抑制型缓蚀剂,但主要是抑制阴极反应. 通过吸附理论和动力学公式求出了相应的吸附热力学参数和动力学参数,并根据这些参数详细讨论了缓蚀作用机理.  相似文献   

9.
HCl中溴化十四烷基吡啶在钢表面的吸附及缓蚀作用   总被引:2,自引:1,他引:1  
用失重法和电化学法研究了在1.0 mol/LHC l中20~50℃时溴化十四烷基吡啶(TDPB)在冷轧钢表面上的吸附及缓蚀作用。结果表明,TDPB对钢具有非常好的缓蚀作用,为混合抑制型缓蚀剂,最大缓蚀率为99%,在钢表面的吸附符合Langmu ir吸附模型。求出了相应的吸附热力学参数(吸附自由能ΔG0,吸附热ΔH0,吸附熵ΔS0),并根据这些参数详细讨论了缓蚀作用机理。  相似文献   

10.
用失重法研究了紫竹(Phyllostachys nigra Munro)竹叶提取物PMLE在0.01~0.05 mol/LHCl溶液中对锌的缓蚀作用。结果表明:PMLE对锌在0.01 mol/LHCl溶液中具有良好的缓蚀作用,且在锌表面的吸附符合Langmuir吸附等温式。缓蚀率随缓蚀剂浓度的增加而增大,但随温度和盐酸浓度的增加而减小。通过Van't Hoff方程和Mathur经验动力学公式分别求出了吸附焓ΔHads和腐蚀动力学参数(速率常数k,动力学常数B),并据此参数讨论了PMLE的缓蚀行为。  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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