共查询到19条相似文献,搜索用时 112 毫秒
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硫酰氟(SO2F2),美国商品名叫Vikane(维肯)(含99.8%质量,0.2%惰性杂质),由道化学公司在五十年代后期开发作为建筑熏蒸剂,Vikane(现由Dow Elanco生产)具有消除在建筑物里蔓延的害虫的特性,它不燃,无腐蚀,不会产生异味,它能迅速穿透到建筑材料里,有效地杀死各种建筑物害虫,在散气时迅速散逸,这种物质是一种规定的建筑熏蒸剂,因而被考虑为甲基溴的替代品,自1961年在美国上市以来,它已被用来熏蒸一百万座以上的建筑物,包括博物馆,历史遗迹,珍贵图书馆,政府建筑,科学和医学研究实验室,及食品处理设施,和甲基溴相比较,硫酰氟穿透建筑材料更迅速,广谱杀来各种害虫更有效,在散气后残留在建筑材料中更少,这些特性使它成为替代溴甲烷用于建筑熏蒸的适用替代品。 相似文献
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建筑物用气体熏蒸剂—硫酰氟 总被引:2,自引:1,他引:1
硫酰氟(SO2F2),美国商品名称Vikane(含量99.8%,0.2%惰性杂质),由道化学公司在50年代后期开发作为建筑物熏蒸剂。Vikane(现在由Dow Elanco生产)具有杀灭在建筑物里蔓延的害虫的特性,它不燃,无腐蚀性,不会产生气味,它能迅速穿透到建筑材料里,有效地杀死种建筑物害虫。这种物质是一种规定用的建筑熏蒸剂,因而被考虑为甲基溴的替代品。自1961年在美国面市以来,已被用来熏蒸一百座以 上的建筑物,包括博物馆、历史遗迹、珍贵图书馆、政府建筑、科学和医学研究实验室及食品处理设施。和甲基溴相比较,硫酰氟穿透建筑物更迅速,更有效地广谱杀灭各种害虫,散气后残留在建筑材料中更少,这些特性使它成为替代溴甲烷用于建筑熏蒸的适用替代品。 相似文献
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土传病虫害例如线虫、植物病原真菌和杂草通常在作物移栽前使用土壤熏蒸来防治。以前,在美国甲基溴是一种重要的熏蒸剂,后其被禁用,这使得有关甲基溴替代物的研究再次兴起。当前美国和欧洲关于甲基溴替代物的应用研究通常集中于蔬菜作物生产。但是,在观赏作物上同样迫切需要使用甲基溴替代物。最近在佛罗里达州和加利福尼亚州的研究检验了熏蒸剂替代物在切花生产上的效果。 相似文献
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制备了一种新型的溴化试剂-载溴阴离子交换树脂。在间甲基茴香醚的溴化中,这种溴化剂有良好的选择性及稳定性,产物4-溴-3-甲基茴香醚的产率高达89.2%。 相似文献
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王跃进 《精细与专用化学品》1999,(22)
溴甲烷作为一种性能优良的熏蒸剂,一直被广泛应用于耐久储存品、易腐烂商品及建筑物等的熏蒸,在仓储物保护、检疫及装运前熏蒸中发挥着十分重要的作用。但是,溴甲烷是一种耗减臭氧层的物质,已经被列入逐步淘汰的熏蒸剂。为了中国今后能够实施有效的淘汰,本文就目前在耐久储存品和易腐烂商品熏蒸方面替代溴甲烷的主要技术和方法作了简要介绍。 相似文献
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Cleavage of alkenes by anodic oxidation 总被引:1,自引:0,他引:1
Oxidative cleavage of olefinic double bonds to carboxylic acids, aldehydes or ketones is one of the important reactions in
organic synthesis. Ozonolysis is mostly applied for this purpose, however, high costs for safety precautions in technical
scale conversions demand alternatives. For this purpose different electrochemical methods are investigated. In the direct
oxidation of cyclohexene at a platinum or graphite anode no cleavage occurs, but substituted and rearranged products are obtained.
At the boron doped diamond electrode (BDDE) aliphatic olefins with high oxidation potential are not converted. Electrochemical
ozonolysis by oxidation of water to ozone at the lead dioxide electrode leads to carboxylic acids as cleavage products in
high material yield but low current yield. Anodic bromo-formyloxylation followed by an anodic cleavage provides a two step
conversion of cyclohexene to hexane-1,6-dial derivatives. Thereby anodic discharge of bromide in formic acid leads to (2-bromocyclohexyl)-formate,
which is converted to cyclohexane-1,2-diol and the major part of potassium bromide is recovered for the next cycle. This electrochemical
conversion appears to be an attractive alternative to chemical oxidations with oxygen and catalysts or with hydrogen peroxide.
The diol is cleaved in high yield to hexane-1,6-dial or its acetal either directly or indirectly with periodate as mediator. 相似文献
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为了解决煤中痕量卤素-溴的燃烧产物排放造成的污染,通过固定床管式炉煤燃烧试验,研究了燃煤过程中添加钙基质(CaO)作为固溴剂对溴化物析出的影响。结果表明:钙基质(CaO)能够有效地降低燃煤过程中溴化物的排放量;采用预混与喷射相结合的方式向锅炉中添加固溴剂能够最大限度的吸收燃煤过程中析出的溴化物,减少溴化物的排放量。此外,钙基固溴剂的脱溴效率还受燃烧温度、停留时间、钙基固溴剂(CaO)的添加量、燃烧气氛等因素的影响,燃煤过程中控制合理的钙基质与溴化物的反应条件有利于提高钙基质的脱溴效率。 相似文献
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Tushar S. Deore Amid L. Sadgar Radha V. Jayaram 《Journal of surfactants and detergents》2021,24(1):185-190
Ionic liquids have been found to be suitable alternatives to volatile organic solvents in chemical transformation. Through a proper choice of cations and anions, the properties of an ionic liquid can be tuned so that it resembles an amphiphile. Such specially designed molecules are known as surface-active ionic liquids (SAIL). Like conventional surfactants, SAIL also form aggregates in an aqueous medium. Studies show that the mixing of SAIL with conventional surfactants leads to synergistic micellization. However, very few reports are available on the application of such systems as reaction media. Present study focuses on the application of mixed micelles of 1-tetradecyl-3-methylimidazol-1-ium bromide, ([C14mim]Br) with nonionic surfactant, Octylphenol ethoxylate with 10 moles of ethylene oxide (OPE-10). Enhanced solubilization and selective catalytic oxidation of toluene using hydrogen peroxide as an oxidant and tungstic acid as a catalyst have been studied in detail using this system. 相似文献
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David Eugene Kimbrough Lina Boulos Sirikarn Surawanvijit Paul Westerhoff Howard An I.H. “Mel” Suffet 《臭氧:科学与工程》2012,34(4):269-279
In four recently published articles, a process for the oxidation of bromide to bromine and the volatilization of bromine from drinking water sources was presented. This process was shown to be able to remove up to 35% percent of the bromide found naturally in the California State Water Project. Although bromide itself is quite harmless, it has been shown to react with commonly used disinfectants to produce compounds or disinfection by-products (DBPs) of suspected carcinogens. Bromide reacts with ozone to form bromate. This article presents two studies of pilot scale, flow-through electrolytic reactors that oxidize bromide to bromine and volatilize bromine at <pH 3.5, which occurs at the anode as a result of the oxidation of water. One reactor had 14 anodes that were 91 cm deep and the other had 13 anodes 1.2 cm deep. The bromide removal rates were studied at several different water flows and power settings for different bromide concentrations for both reactors. The results show removal of bromide is impacted by water flows and power settings for different bromide concentrations. Effluent from the deep reactor did show some reduction in bromate concentration as compared to control samples but the results were inconsistent. This appeared to be caused by significant differences in the ozone demand produced by different experimental conditions, difficulty determining the concentration of chlorine, and the use of hydrogen peroxide as a dechlorinating agent. Using the shallow reactor, these difficulties were overcome by developing a more consistent determining chlorine concentration, using much larger ozone doses to overwhelm the ozone demand, and by using ascorbic acid instead of hydrogen peroxide. With these changes, it could be shown that the electrolytic reactor not only lowered the concentration of bromide in the water but when ozonated, the amount of bromate formed was reduced in direct proportion to the amount of bromide removed for an equal dose of ozone. 相似文献
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通过试验研究了使用氨-水-溴化锂三元工质对氨吸收式制冷性能的影响。根据现有研究,工质中溴化锂的质量分数设定为5%、10%、15%和20%,试验中发生温度设定为90~130℃,蒸发温度设定为-19~-4℃,冷却水温度设定为22~33℃。通过试验发现,溴化锂质量分数在15%时对COP提升效果最好,发生温度在130℃时性能系数可以达到0.408,蒸发温度在-4℃时性能系数可达0.410,冷却水温度在22℃时性能系数可以达到0.412;而且添加三元工质可以减小精馏能耗且充分利用低品位热能,因此采用氨-水-溴化锂三元工质可以在高效利用热能情况下改善氨吸收式制冷系统的劣势。 相似文献
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N,N′-二乙基喹啉菁染料分子吸附在溴化银溶胶上的表面增强喇曼散射 总被引:1,自引:0,他引:1
N,N′-二乙基喹啉菁染料分子吸附在硫敏化过的溴化银溶胶上产生强的表面增强喇曼散射,这种散射实际上是在直晒银上产生的。N,N′-二乙基喹啉菁染料分子吸附在硫敏化过的溴化银溶胶和银溶胶上的喇曼谱基本相似。而未经硫敏化的溴化银溶胶和经硫敏化后再被高硫酸钠氧化的溴化银溶胶中测不到N,N′-二乙基喹啉菁染料的表面增强喇曼信号。本实验进一步表明,表面增强喇曼散射方法可以用于感光机理的研究。 相似文献