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一、序言在人类生产不断发展的同时,汞的污染给人类带来了很大的威胁。人们希望对于极微量的汞建立简单而灵敏的测定方法。目前,测定汞的多数标准分析法,是采用打萨宗比色法。但这种方法对于测定0.01ppm以下浓度的汞灵敏度不够。在通常的原子吸收分光光度法里(火焰法),汞也是灵敏度较低的元素之一。火花质谱及中子活化分析法测汞,其灵敏度虽高,但设备昂贵,操作也较复杂,不易推广。1964年有人用原子荧光法测汞[1],得到了5.0μg/ml的检出极限。随后有人用无极放电灯作为光源[2],以火焰法测汞,获得了0.1ppm的检出极限。1970年以前,有人用同样的光源[3—16],以各种不同类型的火焰测汞,其绝对检出极限都在微克级的水平。1970年以后又相继提出了电加热的无火焰原子荧光法,如石墨丝法[17],铂环法[18],他们以无极放电灯作为光源,得到汞的检出极限分别为5×10~-(11)g和10~(-8)g。以上这些方法由于需要燃烧气体(如乙炔、氧、氢等)和屏蔽气体(如氩、氮等),以及电加热系统,
I. Preamble While the continuous development of human production, mercury pollution poses a great threat to mankind. It is hoped that a simple and sensitive assay for trace amounts of mercury will be established. At present, most standard mercury determination method is the use of Sassan colorimetric method. However, this method is not sufficient for the determination of mercury concentrations below 0.01ppm. In the usual atomic absorption spectrophotometry (flame method), mercury is also one of the less sensitive elements. Spark mass spectrometry and neutron activation analysis of mercury, its sensitivity is high, but the equipment is expensive, the operation is more complex, not easy to promote. In 1964, mercury was detected by atomic fluorescence [1], and the detection limit of 5.0μg / ml was obtained. Followed by someone with a discharge lamp as the light source [2], the flame method mercury, obtained 0.1ppm detection limit. Before 1970, some people used the same light source [3-16] to measure mercury with various types of flames, and their absolute detection limits were all on the microgram level. After 1970, they also proposed the electric flameless atomic fluorescence spectrometry, such as graphite wire method [17], platinum ring method [18], they use the electrodeless discharge lamp as the light source, the mercury detection limit were 5 × 10 ~ - (11) g and 10 ~ (-8) g. These methods due to the need for combustion gases (such as acetylene, oxygen, hydrogen, etc.) and shielding gas (such as argon, nitrogen, etc.), as well as electric heating system,