电解法生产氯酸钠的阳极研究

分别用钛基铱钽、铱钽锡、二氧化铅和钌钛电极作阳极,测定了它们在强酸性条件下强化电解生命,以及电解生产氯酸钠的阳极电极电位、槽电压和电流效率,比较了４种电极作为电解法生产氯酸钠阳极的优劣。     

钛-二氧化铅阳极电解次磷酸钠制备高纯次磷酸

以六室电解槽为反应槽,分别以石墨电极、钛-二氧化铅电极和钛涂钌电极为阳极,不锈钢为阴极电极,研究了电解法制备成本低、纯度高且环境友好的次磷酸新工艺。结果表明：六室电解槽制得的次磷酸杂质少;与国内外常用石墨和钛涂钌阳极材料相比,钛-二氧化铅电极作为阳极材料在阳极电位、产品浓度及产品室电流效率方面性能优良。钛-二氧化铅电极没有固体沉淀,无其他杂质离子产生,阳极液不必更换,只需定期补充电解消耗的水,属于清洁生产。在最佳电解电流、电解温度、原料浓度和电解时间条件下制得次磷酸产品,经减压富集后其杂质含量能够满足电容器生产的要求。     

氟硼酸铅镀液中电沉积钛基二氧化铅

以电沉积法从氟硼酸铅镀液中制备Ti基PbO2阳极(FB/PbO2)及其掺杂氟离子的FB/F - PbO2阳极.应用计时电位法研究了所制备阳极的电沉积成核速率,发现氟硼酸铅镀液在钛基表面电沉积二氧化铅的结晶速度比硝酸铅镀液更快.采用XRD和SEM技术对这两种电极进行了表征,并与传统的硝酸镀液制备的钛基二氧化铅对比,发现电...     

电化学法预处理TNT废水及机理研究

以TNT碱性废水(又称红水)为研究对象，采用钛基二氧化铅(dimensionally stable anodes)类阳极和不同材料的阴极对该类废水进行电化学处理。研究结果表明：不同的阴极材料、电流密度、pH值、槽电压、电解质浓度及极板间距对废水中CODCr的降解有不同程度的影响，并通过实验证实了电化学反应过程中苯胺类物质中间体的存在。     

锌电积用惰性阳极材料的研究现状

阐述了国内外铅及铅合金阳极、钛基二氧化铅阳极等锌电积用惰性阳极材料的研究现状,并对未来锌电积用惰性阳极材料的发展趋势进行了展望.     

钛基金属氧化物涂层电极的研究进展

钛基金属氧化物涂层电极又称DSA,是一种新型不溶性阳极电极。综述了钛基金属氧化物涂层电极的研究进展,包括钛基钌系涂层电极、钛基铱系涂层电极、钛基二氧化锰电极和钛基二氧化铅电极。介绍了不同钛基涂层电极材料的制备方法、性能特点和应用情况,并对其今后的发展方向作了展望。     

钛基体二氧化铅电极制备改性方法研究进展

寻找稳定性能好及催化性能高的阳极材料是推广电化学水处理技术的关键。钛基体二氧化铅电极在稳定性及催化性方面具有明显优势,但仍存在不少问题。对钛基体二氧化铅电极进行改性以提高其稳定性及催化性成为目前氧化物阳极材料研究中的热点之一。本文主要综述二氧化铅的性质、钛基体二氧化铅电极结构以及针对电极不同结构层进行的技术改性方法;重点阐述采用改性钛材料作为电极基体、在二氧化铅表层与钛基体之间引入中间层、采用杂质元素与杂质颗粒进行掺杂和电极制备方法改进及优化;并指出钛基体二氧化铅电极的发展趋势在于：电极组成形式与成分的多样化,开发新的电极制备技术,以及研究二氧化铅电极的失效机理以便指导电极后续的改性工作等。     

金属阳极电解槽阳极部件腐蚀原因浅析

1 概述 金属阳极替代石墨阳极是氯碱工业的一次重大变革,二者比较而言,金属阳极的网状极片减小了电解过程中的气泡效应,稳定的阴、阳极极距,大大地降低了单槽槽电压。金属阳极电解槽由阳极、阴极箱、阳极底板3大部分组成,其中阳极底板包括钢底板、钛衬板、导电铜板。每台电解槽受隔膜质量和其它因素限制运行时间不同,除槽解体后发现了下列情况。(1)钛衬板孔、钢底板孔发生了轻微和较严重的腐蚀。(2)金属阳极片钛法兰以下无螺纹部分发生腐蚀。(3)经修补后的钛衬板的孔腐蚀更为严重。对以上发生的情况做如下分析和探讨。     

电解铜始极片的制作

1　前言电解铜生产所用的阴极 (即始极片 ) ,是在种板槽中生产出来后再经加工而成的。始极片的制作质量直接关系到电解铜的生产 ,由于技术竞争的原因 ,对始极片的制作工艺、配方、添加剂的作用机理及故障排除等还少有报道 ,作者经过摸索实践 ,积累了一些经验 ,特在此作简要介绍。2　始极片制作工艺流程种板制作除油清洗入槽电解清洗干燥机械加工3　种板制作选用钛板作为种板比较好。钛板具有重量轻、耐腐蚀 ,析出的始极片光滑平整、韧性好、不粘板、板片易剥离、无须使用中性隔离剂等优点。选用的钛板应光滑平整 ,无凹坑、麻点和划痕等 ,否…     

改性二氧化铅阳极的研究

本文以钛极为基体进行改性二氧化铅阳极的研究,研究表明钛基涂上SnO_2A-SbO_y(1.5≤y≤2.5)中间层后,在含有Co_3O_4、Mg_xCo_(3-x) O_4(0≤x≤1)等催化剂的硝酸铅镀液中电沉积二氧化铅阳极,其析氯电位有明显降低;研究还表明在上述催化剂掺杂了SnO_2-SbO_y、ZrO_2等增强剂能进一步改善阳极电化学性能,显著提高电极寿命。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

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.