植物提取物自组装膜在盐酸中对Q235钢的缓蚀作用

以铁线蕨植物提取物(ACE)为成膜物质,在Q235钢表面自组装得到缓蚀膜。通过极化曲线和电化学阻抗谱测试研究了该自组装膜对Q235钢在1 mol/L HCl溶液中的缓蚀性能。结果表明,该自组装膜对Q235钢的阴、阳极腐蚀反应均有抑制作用,可明显减缓Q235钢在盐酸溶液中的腐蚀,且缓蚀作用随ACE质量浓度的增大而增强。ACE分子在Q235钢表面的吸附遵从Langmuir和Frumkin吸附模型,为单分子层吸附,吸附分子之间存在横向吸引力。     

壳聚糖与CTAB复合缓蚀剂对Q235钢的缓蚀性能研究

采用失重法、交流阻抗法和极化曲线法研究了盐酸介质中壳聚糖及其与十六烷基三甲基溴化铵(CTAB)复合缓蚀剂对Q235钢的缓蚀性能。测试结果表明,单独使用壳聚糖作为缓蚀剂,对Q235钢表面有较强的缓蚀性能。当壳聚糖的质量浓度为0.1 g/L时,在1.0 mol/L的盐酸介质中30℃腐蚀24 h,3种方法测得的缓蚀效率均达到85%以上;加入CTAB后,缓蚀性能明显增强,CTAB的质量分数为10%时,缓蚀效率达到了92%以上。2种缓蚀剂在Q235钢表面吸附机理不同且吸附过程相互补充,因此二者复配后缓蚀性能加强。     

细菌胞外物质中糖类对Q235钢的腐蚀研究

细菌及其胞外物质是影响金属腐蚀的重要原因之一。细菌胞外物质的构成较为复杂,各组分对腐蚀的影响也各有不同。主要研究了细菌胞外物质中糖类对Q235钢腐蚀的影响,采用静态失重、电化学等方法研究胞外物质中含量较高的3种常见糖类(葡萄糖、鼠李糖和海藻糖)及其混合物在1 mol/L Na2SO4溶液中对Q235钢的缓蚀作用。结果表明,当糖类的质量浓度在10 g/L时,糖类及其混合物在溶液中对Q235钢都有一定的缓蚀作用,缓蚀率均能达到30%左右,但其效果与铁细菌的氧化作用相比甚微。     

新型吡啶季铵盐的合成和缓蚀性能的研究

合成了新型吡啶季铵盐阳离子缓蚀剂,研究并讨论了其在炼油装置塔顶空冷器、水冷器的1000 ppm HCl～500 ppm H2S腐蚀介质中对Q235钢的缓蚀性能及其与中和有机胺、表面活性剂的配伍性.研究表明,该吡啶季铵盐对Q235钢均表现出较传统咪唑啉季铵盐好的缓蚀性能,该吡啶季铵盐添加量20 ppm时缓蚀效率可达90％以上,对Q235钢腐蚀表现出明显的抑制作用.     

离子液体在甲醇/硫酸介质中对Q235钢表面的缓蚀性能

探究硫酸存在时Q235钢在甲醇中的腐蚀行为,以及离子液体1-丁基-3-甲基咪唑氯盐（[Bmim]Cl）对金属表面的缓蚀作用。通过静态失重法、电化学测试、扫描电子显微镜来测定[Bmim]Cl对Q235钢的缓蚀性能。并利用量子化学计算和分子动力学模拟分析[Bmim]Cl分子的缓蚀机理。在甲醇中随着硫酸含量的增加碳钢的腐蚀速率增加。含有59.51 ml 0.05 mol·L^-1 H₂SO₄的甲醇溶液作为腐蚀介质时,随着[Bmim]Cl浓度升高,缓蚀效率逐渐增大,当浓度为0.6 mol·L^-1时,缓蚀效率达到最佳值,为90.63%,且[Bmim]Cl是主要控制阳极反应的混合抑制剂,SEM分析表明在含有缓蚀剂溶液中浸泡后的Q235钢表面相对于未加缓蚀剂更加平整。前线轨道分析和Fukui指数都表明,离子液体在碳钢表面的吸附位点分布在咪唑环上,与Fe发生化学吸附。分子动力学模拟结果表明缓蚀剂分子以阳离子[Bmim]⁺平行吸附于金属表面,阴离子Cl^-扩散在溶液中的方式达到缓蚀的效果。理论计算结果与实验结果一致,即[Bmim]Cl在甲醇/硫酸水溶液中对Q235钢具有很好的缓蚀作用,为新型离子液体缓蚀剂研究应用奠定了基础。     

新疆油田高盐含氧体系缓蚀剂的性能研究

为解决油田氧腐蚀问题，以反式对甲氧基肉桂醛、3-氨基苯甲酸为主要原料合成了具有多个吸附位点的席夫碱缓蚀剂TMCAM。首先，通过动态失重法评价了不同浓度的席夫碱缓蚀剂TMCAM在60℃含氧油田模拟配水中对Q235钢的缓蚀性能。结果表明，在TMCAM质量浓度为60 mg/L时，Q235钢的腐蚀速率为0.062 4 mm/a，满足现场要求；TMCAM投加质量浓度为100 mg/L时，Q235钢腐蚀速率仅为0.036 8 mm/a，缓蚀率可达到90%。其次，采用扫描电镜、电化学法、接触角测试等表征技术评价了TMCAM的缓蚀性能并分析其缓蚀机理。结果表明，TMCAM是一种偏阴极的混合型缓蚀剂，TMCAM分子与Fe之间的吸附能力强，且TMCAM可在钢表面形成疏水膜，减少了含氧污水与管道的接触时间，减缓了腐蚀，进而保护了管道。最后，通过分子模拟技术从理论角度分析了缓蚀剂的缓蚀性能与缓蚀剂分子构型之间的关系，结果显示TMCAM分子结构具有较强的吸附能力，高于文献报道的其他席夫碱缓蚀剂。     

一种新型联吡啶双子季铵盐的合成及缓蚀性能

以4,4'-联吡啶和氯化苄为原料,经季铵化反应制备了化合物1,1?-二苄基-4,4?-联吡啶双子季铵盐(PBA),产率为76.3%,通过FTIR、~1HNMR对产物结构进行了表征;利用失重法、电化学技术、AFM考察了PBA对1 mol/L盐酸溶液中Q235钢的缓蚀作用和其在Q235钢表面的吸附行为。结果表明,PBA是一种同时抑制阴、阳极的混合型缓蚀剂,缓蚀率随PBA浓度的增加而增加,随温度的升高而略有降低。当PBA质量浓度为80 mg/L时,缓蚀率可达96.53%。PBA在Q235钢表面的吸附为放热反应,遵循Langmuir等温式,是以化学吸附为主的混合型吸附。PBA在钢表面形成了一层致密的保护膜,大大阻碍了钢腐蚀。使用量子化学法研究了PBA的缓蚀机理,结果表明,PBA的活性区域集中于苯环和杂环上,且PBA分子接受电子的能力大于提供电子的能力。     

O,O’-二(环己基)二硫代磷酸-N,N,N-三乙铵的制备及缓蚀性能研究

制备了酸洗有机缓蚀剂O,O’-二(环己基)二硫代磷酸-N,N,N-三乙铵(NTOD),采用失重法、电化学法研究了NTOD在5%HCl溶液中对Q235钢的缓蚀性能和吸附行为。研究结果表明:NTOD在5%HCl溶液中是一种混合型缓蚀剂,在5%HCl溶液中的最高缓蚀率达到97%;NTOD在Q235钢表面的吸附完全符合Langmuir吸附等温式,属化学吸附。同时,还研究了腐蚀体系温度、酸浓度、放置时间对NTOD缓蚀性能的影响。     

烯丙基硫脲对金属材料在盐酸中的缓蚀性能研究

文章通过静态失重法和电化学法对缓蚀剂烯丙基硫脲在盐酸体系中对金属材料的缓蚀性能进行了研究。分别考察了不同缓蚀剂浓度、挂片温度及不同金属材料等情况下烯丙基硫脲的缓蚀性能。结果表明,烯丙基硫脲对Q235碳钢的缓蚀性能较好,失重法实验结果表明,在20℃下,0.5 mol/L盐酸溶液中加入100 ppm烯丙基硫脲对不锈钢的缓蚀率可达93%;0.5 mol/L盐酸溶液中加入50 ppm烯丙基硫脲对Q235碳钢的缓蚀率可达94%。电化学法实验结果则表明,当烯丙基硫脲浓度达到1000 ppm时,对不锈钢的缓蚀率达到97%,对Q235碳钢的缓蚀率可达98%。     

某天然气处理厂回注水处理系统腐蚀防护方法研究

为了考察回注水系统的腐蚀情况,针对陕北某天然气处理厂含甲醇污水显酸性、 Cl~-和硫化物含量高、腐蚀性强的特点,通过分析污水组成性质,研究污水对20#钢、 Q235B钢和L316钢的腐蚀情况,并利用灰色系统理论建模软件3.0研究各腐蚀因素对Q235B钢腐蚀速率和腐蚀深度的影响程度大小。研究结果表明:L316钢更耐腐蚀,腐蚀速率为0.001 5 mm/a,达到国标0.076 0 mm/a以下,最大腐蚀深度为47.63μm,为3种材质中最低;以腐蚀速率和腐蚀深度作为母因素,在硫化物、 Cl~-、矿化度和pH值4种因素当中,硫化物对应的灰关联度分别是0.75和0.80,是造成腐蚀的最主要因素;采用抗硫缓蚀剂保护法,通过电化学法从3种缓蚀剂中筛选出TS-792C,阻抗数据模拟软件ZSimpWin模拟出等效电路图,其所对应Q235B钢的阻抗最大,Tafel极化曲线拟合下腐蚀速率为0.013 0 mm/a,缓蚀率可达90.26%,抗硫效果最好。在80℃和硫化物含量为300 mg/L时,Q235B钢的腐蚀速率均低于0.076 0 mm/a,在TS-792C投加量为100 mg/L时,回注污水的腐蚀电流密度和腐蚀速率分别为0.462 m A/cm~2和0.050 5 mm/a,均处于最低值,具有良好的耐温、抗硫性能。     

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。