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砷及其化合物有毒并且是致癌物质,水及某些生物链中砷的含量是环境监测中不可缺少的指标。砷也是寻找某些矿物的指示元素。因此,建立准确、快速、灵敏的痕量砷的分析方法是十分必要的。作为测定砷的方法主要有原子吸收光谱法和原子荧光光谱法。在原子荧光法中光源必须应用无电极放电灯,而在原子吸收光谱法中则可应用无电极放电灯或空心阴极灯。据文献介绍,无电极放电灯具有比空心阴极灯更高的强度、较好的原子吸收灵敏度和线性,但稳定性不如空心阴极灯,寿命比较短,且需要专用的电源。因此有时还必须应用空心阴极灯。砷导电性差、性脆,在常压下加热只升华而不熔化,这给砷阴极的制作带
Arsenic and its compounds are toxic and carcinogenic, and the amount of arsenic in water and certain biological chains is an indispensable indicator of environmental monitoring. Arsenic is also an indicator element for finding certain minerals. Therefore, the establishment of accurate, rapid and sensitive trace arsenic analysis method is very necessary. As a method of determination of arsenic are atomic absorption spectrometry and atomic fluorescence spectrometry. In atomic fluorescence spectroscopy, electrodeless discharge lamps must be used, whereas in atomic absorption spectroscopy electrodeless discharge lamps or hollow cathode lamps can be used. According to the literature, electrodeless discharge lamps have higher intensity than hollow cathode lamps, better atomic absorption sensitivity and linearity, but their stability is not as good as that of hollow cathode lamps. Their life span is relatively short and they require special power supply. It is sometimes necessary to use hollow cathode lamps. Poor conductivity of arsenic, the nature of crisp, under normal pressure heating only sublimation without melting, which gives the arsenic cathode production zone