在pH 2-7的溶液中,碘汞酸钾和溴化十六烷基吡啶(CPB)反应生成离子缔合物,在390 nm处有共振散射峰,峰强度随汞(Ⅱ)浓度的增加而急剧增大.在试验条件下,汞(Ⅱ)的线性范围为15-200 μg ·L-1,检出限为5 μg·L-1,用于合成水样和环境水样中汞(Ⅱ)的测定,在4个浓度水平测得结果的RSD均小于1.5%,用标准加入法测得的回收率在94.9%至102.1%之间.

In a slightly acidic or nearly neutral solution of pH 2-7,an ionic association product was formed by the reaction between potassium mercuric tetraiodide and cetylpyridine bromide electrostatically.A resonance scattering peak was found at 390 nm of the spectrum.It was found that the intensity of the resonance scattering peak increased abruptly with the increase of concentration of mercuric ion,and that linear relationship between these two parameters was found in the range from 15-200 μg·L-1 of Hg(Ⅱ),with a detection limit of 5 μg·L-1.In its application to the determination of traces of mercury(Ⅱ) in water samples,RSD′s found at 4 different concentration levels were less than 1.5%,and results of recoveries obtained by standard addition method were in the range of 94.9%-102.1%.