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Ref. No. [UMCES] CBL 2015-010
ACT VS15-03
Figure 3.
Time series of the Campbell Scientific Instruments pH test instrument pH results along with
the dye reference pH results for the complete ten week lab test. Results include nine rapid pH transition
tests conducted at each temperature and salinity condition. Detailed plots of each transition test are
provided in Appendix I.
Results were further examined for the stable portions of the test for each of the source
waters and these data do not include any of the pH shifts or temperature shifts. Again, no data
were generated during the initial three weeks of seawater trials due to the battery failure.
During the brackish water trials, salinity was maintained to within 0.11 units (range =
21.75 to 21.86) with an average of 21.80 and temperature was maintained to within 0.7
o
C for
each set point (Fig. 4 top). The first temperature trial ranged from 9.95 to 10.67
o
C, with an
average of 10.09
o
C, the second temperature trial ranged from 20.02 to 20.40
o
C, with an average
of 20.20
o
C, and the third temperature trial ranged from 30.18 to 30.54
o
C, with an average of
30.43
o
C. Time series results of the Idronaut 305 Plus started six days into the brackish water test
and no results are were available for the 10
o
C trial. Instrument results along with reference
Metrohm data and reference dye pH data are shown in figure 5 (middle panel) and the time series
of the calculated difference between instrument and reference pH are shown in the bottom panel.
The average difference between the Idronaut 305 Plus and reference pH for the remaining
brackish water component was 0.006 ± 0.072, with a total range of -0.091 to 0.066 (N=53).
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