DPD光度法与便携仪器法测定游离氯的比较研究

目的：比较DPD光度法和便携仪器法测定游离氯的特点，以便合理选择和应用。结果：DPD光度法和便携式仪器法精密度均较好，DPD光度法线性一般，重复性较差。实际样品测定表明：便携式仪器法测得低浓度水样RSD为18.8%，高浓度RSD为4.7%；DPD光度法测得低浓度水样RSD为2.4%，高浓度水样RSD为3.9%。结论：便携式仪器法快速、简便的特点适合在现场进行测定，DPD光度法操作繁琐，但测定低浓度水样时比便携式仪器法准确度高。

Comparison of DPD Spectrophotometry and Portable Detector for Testing Residual Chlorine

Objective：To compare two methods for testing residual chlorine in water for reasonable selection and application.Results：Both of the two methods had good precisions.The linear of DPD Spectrophotometry was general.And this method had bad repetition.Determination of the samples showed that in method porta-ble detector,low concentration RSD was 18.8%,high concentration RSD was 4.7%;in method DPD Spectro-photometry,low concentration RSD was 2.4%,high concentration RSD was 3.9%.Conclusion：Method portable detector is more advantageous and easier to use on field.Though method DPD Spectrophotometry had the complex operation,it was more accurately than method portable detector for low concentration detection.