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Ref. No. [UMCES] CBL 2016-014
ACT VS16-05
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Figure I.
Response of the Hach HL4 LDO (sn 0431) to changing dissolved oxygen concentrations
at 30.6
o
C and S=34.43.
Top Panel
: Time series of instrument readings and Winkler reference
samples drawn at level of sensor foil in well-mixed test tanks.
Bottom Panel
: Corresponding
offset between instrument reading and Winkler DO reference sample during exposure trial. Dotted
line represents zero offset from reference. Note that a significant instrument clock drift occurred
during the trial resulting in missed sample intervals and loss of records.