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污泥中的难降解有机污染物是影响污泥资源化利用的主要原因之一。综述了污泥中主要难降解有机物多环芳烃在国内外的污染现状,并分别从生物法及物理化学法处理污泥多环芳烃进行概述,同时对污泥中的多环芳烃的处理做出展望。 相似文献
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卤代芳烃是重要的有机合成中间体,被广泛应用于医药、农药化学品及天然产物的合成当中[1-4]。卤代芳烃主要分为氯代、溴代和碘代三种。芳环溴代后的产物,除了可以和镁或者锂反应生成有机金属试剂并进一步与很多类化合物反应外[5-8],还可以在一些过渡金属催化下,方便的、温和高效的发生一系列偶联反应。这些反应有Ullmann biaryl coupling[9],Heck reaction[10],Suzuki cross-coupling[11],Stille reaction[12],Hiyama[13],Kumada[14],Negish[15],Sonogashira cross-coupling[16]等。文章详细介绍了四类芳环上溴制备溴代芳烃的方法。 相似文献
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多环芳烃是一个全球性的污染物,存在于许多环境介质中。本文详细介绍了前线轨道理论及其对多环芳烃的应用,并综述了国外对多环芳烃使用前线轨道理论计算并预测降解反应方向和产物的研究,同时,对未来多环芳烃的理论研究进行了展望。 相似文献
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三种新型溴代芳胺类阻燃剂的合成研究 总被引:1,自引:0,他引:1
合成了三种溴代芳胺类阻燃剂∶十溴二苯胺、双(2,3,5,6 四溴 4 氨基苯基)甲烷、双(3,5 二溴 4 氨基苯基)甲烷,并对产品的后处理进行了探讨。实验还发现非溶剂法不适合于多溴代芳胺类化合物的合成。 相似文献
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Four commercial asphalt release agents were chemically characterized using different analytical methods. Functional groups and molecular weight distributions were determined by fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), gel permeation chromatography (GPC) and mass spectrometry (MS). General compositions of the agents were obtained as petroleum hydrocarbons, fatty acid methyl esters (FAMEs), fatty acids and glycerides using gas chromatography-mass spectrometry (GC-MS) and MS probe inlet method. The contents of health related analytes, such as aromatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs), were determined. Asphalt release agents emission was investigated using thermogravimetric analysis (TGA) and headspace solid-phase microextraction (HS-SPME). The emission proneness as well as emission level of aromatic hydrocarbons from these agents were compared. The results obtained were used for ranking the agents with regard to health hazards. 相似文献
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同位素稀释-气相色谱-质谱法同时测定化妆品中20种多环芳烃类化合物 总被引:1,自引:0,他引:1
建立了一种同位素稀释-气相色谱-质谱法同时测定化妆品中20种多环芳烃类化合物的方法。不同类型化妆品用环己烷以不同方法进行提取,然后采用GC-MS的选择离子模式对20种目标物进行定性、定量分析。方法具有良好线性,相关系数r均大于0.992,定量限为50μg/kg。各组分平均回收率在70.5%~114.5%,相对标准偏差在1.7%~13.6%。采用此方法测定了化妆品中多环芳烃的水平,发现某些化妆品中存在萘、1-甲基萘和2-甲基萘。 相似文献
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Crosslinked polystyrene beads modified with polar groups for the separation of aromatic/aliphatic hydrocarbons 下载免费PDF全文
Crosslinked polystyrene (CPS) beads modified with polar groups for the separation of aromatic/aliphatic hydrocarbons were successfully prepared. The synthesized beads were characterized by Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, and thermogravimetric analysis. The effects of the crosslinking agents and polar groups on the swelling and selectivity performances toward n‐heptane/toluene mixtures were studied. Impressively, the results indicated that the sulfone‐modified CPS beads obtained a high toluene selectivity. Further adsorption tests with a variety of aromatic/aliphatic hydrocarbons were carried out at 50°C with initial aromatic concentrations of 13 wt %, and the results showed that the beads had a preferential selectivity for aromatic hydrocarbons, in particular, a higher separation factor of 6.76 for benzene/cyclohexane mixtures. We expect that modified CPS beads will serve as an effective material for the selective separation of aromatic/aliphatic hydrocarbons in chemical and petrochemical fields. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40156. 相似文献
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采用愈创木酚作为生物质模型化合物,以ZSM-5为催化剂,在固定床反应器中研究了反应温度、质量空速以及分压对热解产物产率、选择性的影响,并考察了催化剂的积炭情况。结果表明,愈创木酚催化热解的主要产物为酚类,其次是芳香烃。温度对产物分布有显著影响。催化剂适量的积炭有利于提高烯烃和芳香烃的产率。根据愈创木酚催化热解反应产物分布,推测其主要反应为脱除甲氧基形成酚类,进一步芳构化形成芳香烃。本文研究结果为研究生物质催化热解反应机理提供了理论依据。 相似文献
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Abstract Exposure to polycyclic aromatic hydrocarbons can result from numerous sources including dietary as well as environmental. Exposure to polycyclic aromatic hydrocarbons has been well-established through combustion sources, particularly coal-fired power plants, automobile and diesel exhaust emissions, and the burning of fossil fuels. In addition, exposure to polycyclic aromatic hydrocarbons occurs through the intake of tobacco smoke, both mainstream and sidestream, and this exposure potentially represents one of the highest concentrations of polycyclic aromatic hydrocarbons to which we can be exposed. The plethora of chemicals found in tobacco presents considerable problems when trying to assess biological exposures to single or multiple compounds since the interactions of each of the chemicals with each other may deter the detection of the previous compound. In addition other materials found in tobacco may mask selective detection of certain compounds thereby minimizing their quantitative and qualitative analysis in biological products exposed to tobacco. Previous studies from our laboratory have focused on the detection and characterization of biological markers to aromatic hydrocarbons, particularly in the application of protein biomarkers. In addition, our research has focused on the characterization of biomarkers of tobacco related products during specific time frames of pregnancy ranging from early first trimester pregnancies to third trimester and delivery samples. In the present series of investigations, we investigated the application and utilization of breast milk as a biological marker of postdelivery exposure of neonates to polycyclic aromatic hydrocarbons. 相似文献