||Study to Improve Dissolved Oxygen Analysis Techniques to Facilitate Water Quality Field Survey Applications.
Raibl, R. W. ;
Testerma, M. K. ;
||Arkansas Univ., Fayetteville. Water Resources Research Center.
||Pub-13; DI-14-31-0001-3804; OWRR-A-017-ARK; 10559,; A-017-ARK(1)
( Water analysis ;
( Dissolved gases ;
Measuring instruments) ;
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
Many measurements of dissolved oxygen in water need to be made in field situations where recalibration techniques would be difficult and where making temperature corrections is time consuming for operators who may be making numerous measurements. This study was directed toward design of a compensation circuit for a dissolved oxygen electrode which will give the best possible measurement over a large water temperature range of 5C-35C without the necessity of recalibration. Studies were made of the temperature characteristics of dissolved oxygen probes and several electronic circuits with different configurations and components are described. Experimental data using two of the circuits are reported. One method involved using an integrated circuit multiplier module. The best temperature compensation was obtained for a circuit based on a design in which two thermistors were incorporated.