对用作水质色度测定标准的铂(Ⅳ)-钴(Ⅱ)溶液和铬(Ⅵ)-钴(Ⅱ)溶液的吸收光谱及色度学特性作了比较研究,从而对应用后者代替前者作为标准的可行性和合理性作出判断。结果表明:尽管两者之间存在色度学上的差异以及同色异谱问题,但在色调上人眼难以分辨,而且应用铬(Ⅵ)-钴(Ⅱ)溶液作标准,在实际测量时引入的误差均在允许误差范围以内。然而,对光照及温度的稳定性而言,铬(Ⅵ)-钴(Ⅱ)溶液较铂(Ⅳ)-钴(Ⅱ)溶液差,因此在应用铬(Ⅵ)-钴(Ⅱ)溶液时应注意其保存方法和有效使用时间。

A comparative study on the absorption spectra and the colorimetric characteristic of Pt(Ⅵ)-Co(Ⅱ) solution and Cr(Ⅵ)-Co(Ⅱ) solution was made to prove the feasibility and rationality of the use of the later instead of the former solution as standard in the determination of colority of water. It was found that in spite of the presence of difference in colorimetric factors and of the metamerism character, the difference of color between the 2 standard solutions was hardly be distinguished by naked human eyes, and that the errors due to the use Cr(Ⅵ)-Co(Ⅱ) solution as standard were within the tolerable values. However, it was also found that the Cr(Ⅵ)-Co(Ⅱ) standard solution was less stable than the Pt(Ⅳ)-Co(Ⅱ) standard solution against illumination and temperature, hence attention should be paid to the storage and time of expiration of the Cr(Ⅵ)-Co(Ⅱ) solution in use.