双硫腙—Pb比色法,有混色法和单色法。其鳌合物为红色,最大吸收峰在500nm左右。双硫腙试剂绿色、本底深过量,且在500nm处有重迭。并随Pb含量不同过量双硫腙为变量。再者双硫腙试剂在不同碱性环境中在水相的分配也不尽相同。故混色法采用固定双硫腙试剂做空白,来消除本底干扰,显然会造成较大误差。单色法虽能很好地消除本底干扰、但增加 Dithizone-Pb colorimetric method, a mixed color method and monochromatic method. The chelate is red, the maximum absorption peak at about 500nm. Dithizone reagent green, background overdose, and overlap at 500nm. And with different Pb content of excessive dithizone as a variable. Furthermore dithizone reagents in different alkaline environment in the water phase distribution is not the same. Therefore, the color mixing method using a fixed dithizone reagent blank, to eliminate background interference, obviously will cause greater error. Monochrome method can well eliminate background interference, but increased