以H3PO4为提取剂,通过微波提取的方法,采用高效液相色谱-氢化物发生原子荧光光谱联用技术(HPLC-HG-AFS)实现了垃圾焚烧飞灰中砷的价态测定。重点探究了H3PO4存在下,使用HPLC-HG-AFS测定无机砷(As(Ⅲ)和As(Ⅴ)价态的色谱条件。结...以H3PO4为提取剂,通过微波提取的方法,采用高效液相色谱-氢化物发生原子荧光光谱联用技术(HPLC-HG-AFS)实现了垃圾焚烧飞灰中砷的价态测定。重点探究了H3PO4存在下,使用HPLC-HG-AFS测定无机砷(As(Ⅲ)和As(Ⅴ)价态的色谱条件。结果表明,当使用(NH4)2HPO4为流动相时,H3PO4的存在会对As?的分析造成不利影响,增大流动相流速对改善这种状况几乎没有效果;而使用Na2HPO4-KH2PO4混合溶液(p H 6.864)作为流动相时,可以显著降低H3PO4对As(Ⅴ)分析的干扰。在优化的色谱条件下,As(Ⅲ)和As(Ⅴ)可在5 min内实现分离,检出限分别为0.063和0.110μg/L。在标准物质加标回收实验中,各价态回收率良好(86.5%-102.5%)。利用本方法对来自4个垃圾焚烧电厂的飞灰样品进行分析,发现垃圾焚烧飞灰中的砷主要以As?的形式存在。展开更多
The Al/fly ash composites are fabricated by liquid reactive sintering P/M process with fly ash particles as intensifying phases. The reactivity and newly formed phases during liquid sintering process have been analyze...The Al/fly ash composites are fabricated by liquid reactive sintering P/M process with fly ash particles as intensifying phases. The reactivity and newly formed phases during liquid sintering process have been analyzed by combing Thermochemicdl data base calculation and XRD characterization. The results show that some of constituents in fly ash have reacted with liquid aluminum so that the elemental Si, Fe, Ti as well as some amount of intermetallic compounds occur. The properties of aluminum/fly ash composites have been improved. With the fraction of fly ash increase, the composite density decreases; the hardness and the modulus of the composite increases, and the composite wear resistance are significantly increased. The fly ash reinforced composites represent a sort of low cost product with possible widespread applications in the automotive, small engine, and electromechanical machinery sectors.展开更多
文摘以H3PO4为提取剂,通过微波提取的方法,采用高效液相色谱-氢化物发生原子荧光光谱联用技术(HPLC-HG-AFS)实现了垃圾焚烧飞灰中砷的价态测定。重点探究了H3PO4存在下,使用HPLC-HG-AFS测定无机砷(As(Ⅲ)和As(Ⅴ)价态的色谱条件。结果表明,当使用(NH4)2HPO4为流动相时,H3PO4的存在会对As?的分析造成不利影响,增大流动相流速对改善这种状况几乎没有效果;而使用Na2HPO4-KH2PO4混合溶液(p H 6.864)作为流动相时,可以显著降低H3PO4对As(Ⅴ)分析的干扰。在优化的色谱条件下,As(Ⅲ)和As(Ⅴ)可在5 min内实现分离,检出限分别为0.063和0.110μg/L。在标准物质加标回收实验中,各价态回收率良好(86.5%-102.5%)。利用本方法对来自4个垃圾焚烧电厂的飞灰样品进行分析,发现垃圾焚烧飞灰中的砷主要以As?的形式存在。
文摘The Al/fly ash composites are fabricated by liquid reactive sintering P/M process with fly ash particles as intensifying phases. The reactivity and newly formed phases during liquid sintering process have been analyzed by combing Thermochemicdl data base calculation and XRD characterization. The results show that some of constituents in fly ash have reacted with liquid aluminum so that the elemental Si, Fe, Ti as well as some amount of intermetallic compounds occur. The properties of aluminum/fly ash composites have been improved. With the fraction of fly ash increase, the composite density decreases; the hardness and the modulus of the composite increases, and the composite wear resistance are significantly increased. The fly ash reinforced composites represent a sort of low cost product with possible widespread applications in the automotive, small engine, and electromechanical machinery sectors.