An Automated Precise Winkler Titration for Determining Dissolved Oxygen on Board Ship
نویسندگان
چکیده
An automated titration for the Winkler method is presented for measuring primary productivity in the ocean. The system is based on a microcomputercontrolled titration with potentiometric endpoint detection. By the use of 0.005-N sodium thiosulfate as a titrant and a program designed to shorten the time for measuring, the method achieves a precision of 0.04% coefficient of variation with a range of 0.01 to 0.10% for six replicates of samples at oxygen concentration of 70 to 250 μM. It takes about four to five minutes to measure one sample.
منابع مشابه
Limnol. Oceanogr., 44(4), 1999, 1148–1154
Several researchers have proposed spectrophotometric modifications of the Winkler titrimetric method for measuring dissolved oxygen (DO). These modifications, although simple, are not widely used because of concern about accuracy, calibration, and possible sources of interference. Here we show, using natural samples from lakes and rivers as well as samples manipulated in the laboratory, that th...
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