A photometric method to determine molecular oxygen in water was developed. When manganese(II) is oxidized by oxygen under alkaline conditions, the presence of polyphosphate can prevent precipitation due to a coacervate reaction. The oxidized manganese later dissolves in acid to form a pink Mn(III) species, which has a stable UV/vis spectrum. Monitoring of the oxygen concentration based on the absorbance of the pink Mn(III) species at 517 nm showed a strong correlation with both the Winkler method and an optical sensor. As a result, the present method can measure not only dissolved oxygen, but also fine bubbles oxygen in in the water sample with high reliability (0 – 26 mg dm⁻³, r² = 0.9995). During this process, no significant interference from nitrite or metal ions was observed. The accuracy of the measurement was steady at high temperatures of the water samples (≤ 363 K).

开发了一种测定水中分子氧的光度法。当锰 (II) 在碱性条件下被氧气氧化时，多磷酸盐的存在可以防止由于凝聚层反应而导致的沉淀。氧化后的锰随后溶解在酸中，形成粉红色的 Mn(III) 物质，其具有稳定的紫外/可见光谱。基于粉红色 Mn(III) 物质在 517 nm 处的吸光度监测氧浓度表明与 Winkler 方法和光学传感器都具有很强的相关性。因此，本方法不仅可以测量溶解氧，还可以测量水样中的细气泡氧，可靠性高（0 – 26 mg dm ^-3 , r ²= 0.9995）。在此过程中，未观察到亚硝酸盐或金属离子的显着干扰。在水样高温 (≤ 363 K) 下，测量精度稳定。