Abstract
Nowadays, it is still a challenge for commercial nitrate sensors to meet the requirement of high accuracy in a complex water. Based on deep-ultraviolet spectral analysis and a regression algorithm, a different measuring method for obtaining the concentration of nitrate in seawater is proposed in this paper. The system consists of a deuterium lamp, an optical fiber splitter module, a reflection probe, temperature and salinity sensors, and a deep-ultraviolet spectrometer. The regression model based on weighted average kernel partial least squares (WA-KPLS) algorithm together with corrections for temperature and salinity (TSC) is established. After that, the seawater samples from Western Pacific and Aoshan Bay in Qingdao, China with the addition of various nitrate concentrations are studied to verify the reliability and accuracy of the method. The results show that the TSC-WA-KPLS algorithm shows the best results when compared against the multiple linear regression (MLR) and ISUS (in situ ultraviolet spectrophotometer) algorithms in the temperatures range of 4–25 °C, with RMSEP of 0.67 µmol/L for Aoshan Bay seawater and 1.08 µmol/L for Western Pacific seawater. The method proposed in this paper is suitable for measuring the nitrate concentration in seawater with higher accuracy, which could find application in the development of in-situ and real-time nitrate sensors.
Highlights
The prediction ing from 0 μmol/L to 100 μmol/L were measured with the system
A different method for measuring nitrate concentration in seawater based on deepultraviolet spectral sensor is proposed studied in this paper
R2ultraviolet spectrometer to determine the nitrate concentration in seawater interference
Summary
With the development of the economy, agricultural fertilizers and various sewages are continuously discharged to the coastal seawater [1,2] and have led to the abnormal reproduction of algae and even red tide outbreaks. This abnormality does bring serious consequences to nature and human beings, and results in huge losses to the local economy [3,4]. Developing nitrate sensors with high accuracy in a complex water is of great significance for the exploration of the mechanisms behind red tide outbreaks. It is still a challenge today for commercial in-situ nitrate sensors to meet the demand
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
