3 . the exposure time and recovery time of the optode membrane are 5s and 25s respectively . the reversibility of the fluorescence signal was evaluated by alternate measurements in air saturated water and nitrogen - purged water . the relative standard deviation 与标准法相对照,用本仪器系统测定了不同盐度的人工海水中的溶解氧浓度,两种方法在不同浓度水平下的溶解氧测定值均无显著性差异。