The COD of water sampling may have different results varying from kinds and concentrations of oxidizing agent,acidity of reaction solution,reaction temperature and time and if there are catalysts.

• 水样的化学需氧量,可由于加入氧化剂的种类及浓度,反应溶液的酸度,反应温度和时间,以及催化剂的有无而获得不同的结果。