毛细滴管数滴微型滴定法野外快速测定水中溶解氧

Fast Determination of Dissolved Oxygen by Counting Drop of Capillary Burette Micro Titration

用毛细滴管数滴微型滴定法对水中溶解氧进行了现场快速测定。实验结果表明，该法的不确定度Urel（C）约为1．6％，与常量滴定法相当，符合国家标准。该法以自制的液滴体积为0．01～0．02mL的聚乙烯毛细滴管就地进行滴定，避免了水样长期保存和运输中产生的误差。其主要仪器外形小巧、便于携带，滴定快速、准确，滴定剂用量仅为65～100滴。完全能够满足现场快速水盾测定和野外水环境监测的需要。

Fast determination of dissolved oxygen was performed by counting drop of capillary burette microtitration. The results showed that the uncertainty （Urel） of the method was about 1.6%, an equivalent value to the conventional titrimetric analysis and is conformed to national standards. A polyethylene capillary burette with the single drop volume of 0. 01～0. 02 mL was used for the microtitration and the possible error resulting from the keeping and transportation of the water samples could be avoided. The apparatus is small, portable, the titration process is rapid and only 65～100 drops of titrant is needed, which would satisfy the requirements of spot analysis and rapid monitoring of water samples.