基于荧光猝灭溶解氧传感器的校准方法研究

溶解氧是海洋水质监测的常规关键参数,基于荧光猝灭原理研制的溶解氧传感器具有准确度高、稳定性好和可长期在线测量等优点,已经被广泛用于海水溶解氧浓度监测。针对传感器可能发生的数据漂移和显著偏差可能造成的准确度问题,本文设计了一套专门的校准装置和校准方法。通过严格控制校准水体的温度和溶解氧浓度,测量待校准传感器和参比传感器的相移、温度和溶解氧浓度数据,拟合获取传感器校准系数,实现对光学溶解氧传感器的单个多点校准。传感器校准值与参比值偏差在±8μmol·L^–1以内。实验室和海水现场比测结果显示,校准结果达到传感器性能指标要求。此校准装置及方法并不局限于光学溶解氧传感器,具有良好的推广价值。

Calibration method of a fluorescence quenching dissolved oxygen sensor

Dissolved oxygen is one of the conventional key parameters for the monitoring of marine water quality.The dissolved oxygen sensor based on the principle of fluorescence quenching has been widely used in the monitoring of dissolved oxygen concentration in the sea owing to its high accuracy,good stability,long-term in situ measurement,and other advantages.Aiming at the accuracy problem caused by the possible data drift and significant deviation of the sensor,this study designed a special calibration device and calibration method.Under the strict control of temperature and the dissolved oxygen concentration of the calibrated water body,the phase shift,temperature,and dissolved oxygen concentration data of the sensor and reference sensor to be calibrated were measured.The sensor calibration coefficient was obtained by fitting.Single multipoint calibration of the optical dissolved oxygen sensor was realized.The calibration value of the sensor was within±8μmol·L^–1.Laboratory results and field seawater comparison showed that the calibration results meet the requirements of the sensor performance indexes.The calibration device and method are not limited to optical dissolved oxygen sensors and have a good popularization value.