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垃圾焚烧厂周围环境中2,3,7,8-TCDF的测定和分析
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作者 黄宇轩 宋佳玲 张月洋 《广州化工》 CAS 2019年第13期148-150,共3页
以某垃圾焚烧厂附近的大气样品和土壤样品为研究对象,采用同位素稀释高分辨气相色谱-高分辨质谱法(HRGC/MS)联用技术分析典型的二噁英类物质2,3,7,8-四氯代二苯并呋喃(2,3,7,8-TCDF)。结果表明,大气样品方法回收率为62%~134%,大气采样点... 以某垃圾焚烧厂附近的大气样品和土壤样品为研究对象,采用同位素稀释高分辨气相色谱-高分辨质谱法(HRGC/MS)联用技术分析典型的二噁英类物质2,3,7,8-四氯代二苯并呋喃(2,3,7,8-TCDF)。结果表明,大气样品方法回收率为62%~134%,大气采样点中2,3,7,8-TCDF的毒性当量浓度为2.02×10-6~8.57×10-6ngI-TEQ/Nm3,其中颗粒相浓度占比大于气相浓度。土壤样品方法回收率为82%~145%,土壤样品中2,3,7,8-TCDF的毒性当量浓度为0.11~0.42ngI-TEQ/kgdm,可以达到相关标准要求。 展开更多
关键词 垃圾焚烧厂 毒性当量 2 3 7 8-tcdf
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TCDF25颗粒物料包装组合机
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《粮油加工与食品机械》 2004年第6期32-32,共1页
关键词 tcdf25颗粒物料包装组合机 湖北省大冶粮机有限公司 电脑控制计量 技术特点 产品介绍
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质谱/质谱法快速检出国产五氯酚中的痕量剧毒杂质—四氯二苯并呋喃 被引量:2
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作者 蒋可 徐晓白 《环境科学学报》 CAS CSSCI CSCD 北大核心 1990年第1期96-100,共5页
多氯二苯并二(口恶)(口英)(PCDD)及多氯二苯并呋喃(PCDF)是化学结构相象的二组剧毒化合物.1976年意大利的Seveso发生污染事件后,它们对人体的伤害及生态环境的影响受到了世界上环境学家和生态学家的广泛重视.PCDD和PCDF各有75个和135个... 多氯二苯并二(口恶)(口英)(PCDD)及多氯二苯并呋喃(PCDF)是化学结构相象的二组剧毒化合物.1976年意大利的Seveso发生污染事件后,它们对人体的伤害及生态环境的影响受到了世界上环境学家和生态学家的广泛重视.PCDD和PCDF各有75个和135个异构体,其毒性差别可达1000—10000倍,其中的十个异构体(包括2,3,7,8-四氯二苯并二(口恶)(口英),TCDD)已被列入对动物具有最大毒性的一批天然和人为毒物之内,它们会引起肝损伤、氯痤疮、神经系统损伤及致突变、致畸、致癌.急性皮肤毒性的LD_(50)值为1—100μg/kg,对猴子的LD_(50)值,TCDD是30—70μg/kg,TCDF是1000μg/kg,Kara-sek建议人体(50kg体重)对TCDD和TCDF的允许暴露水平是2 pg/day(致癌性).这类化合物具有脂溶性,易被土壤吸附,在自然环境中代谢降解速度缓慢。 展开更多
关键词 tcdf 五氯酚 质谱/质谱法
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Determination of the Most Toxic Polychlorodibenzofurans in Fresh Milk from Southwest Iran
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作者 Azadeh Nakisa Zahra Nazari Khorasgani +2 位作者 Mohsen Rezaei Nima Imani Saeid Rezaee 《Food and Nutrition Sciences》 2015年第11期955-963,共9页
Background: Today’s presence of polychlorinated dibenzofurans (PCDFs) in foodstuff, such as milk and milk products, is considered to be the major concern for human health. This study was aimed to determine the concen... Background: Today’s presence of polychlorinated dibenzofurans (PCDFs) in foodstuff, such as milk and milk products, is considered to be the major concern for human health. This study was aimed to determine the concentrations of the most toxic congeners of furans in pasteurized milk samples produced in southwest Iran. Material and method: 15 composite samples of pasteurized milk were collected from 3 major dairy factories in Khuzestan Province (southwest of Iran) in summer, autumn and winter from July 2011 to March 2012. After precipitation of the proteins, fat phase was reduced and extracted with hexane and ether. After dehydration, furans existed in fat percolated with hexane through a column chromatography that contained respectively silica gel/silver nitrate, silica gel, silica gel/sulphuric acid and with percolating output through another column that contained activated charcoal and silica gel and washed the lower column with a mixture of dichloromethane-hexane and toluene, concentrated and dissolved in mobile phase and analyzed using HPLC: 150 mm × 4.6 mm ID, 5 μm cosmosil 5 NPE column equipped with a UV detector at 254 and 235 nm, mobile phase: methanol/water (80:20, v/v) at flow rate of 1 ml/min. Results: All samples were found to be contaminated with furans. The average concentration of 2,3,7,8 TCDF and 2,3,4,7,8 PCDF were 1.91 pg/g and 1.77 pg/g in lipid content ranging from 2% to 3% respectively. The mean total content of furans in milk fat was 0.36 TEQ (Toxic Equivalency) pg/g which was below the recommended EU (European Union) threshold value 3 pg (WHO-PCDFs-TEQ/g fat). Also, result showed that there were statistically significant differences between each factory during 3 seasons. 展开更多
关键词 POLYCHLORINATED DIBENZOFURANS 2 3 7 8 tcdf 4 8 PCDF MILK HPLC
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OH自由基引发的2,3,7,8-四氯代二苯并呋喃降解机理的理论研究
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作者 张坤 孙胜敏 张辉 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2014年第4期103-109,共7页
对2,3,7,8-四氯代二苯并呋喃(2,3,7,8-TCDF)的OH自由基加成反应机理以及后续的单分子降解反应机理进行了理论研究.从微观反应动力学角度解释了常温下2,3,7,8-TCDF作为二噁英类物质难降解的根本原因,并阐述了其在高温下的单分子降解反应... 对2,3,7,8-四氯代二苯并呋喃(2,3,7,8-TCDF)的OH自由基加成反应机理以及后续的单分子降解反应机理进行了理论研究.从微观反应动力学角度解释了常温下2,3,7,8-TCDF作为二噁英类物质难降解的根本原因,并阐述了其在高温下的单分子降解反应机理.采用密度泛函理论,计算得到了反应势能面上各稳定点的几何结构,同时完成了简谐振动频率分析,并通过内禀反应坐标理论计算出各反应通道的最低能量路径.结果表明,OH自由基容易加成到2,3,7,8-TCDF上,但后续的降解反应的能垒过高,因此2,3,7,8-TCDF降解反应只能在高温下进行. 展开更多
关键词 2 3 7 8-四氯代二苯并呋喃 二噁英 过渡态 降解机理
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