Thermo Scientific Dionex ICS-5000, Руководство оператора

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Dionex ICS-5000 Operator’s Manual
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Doc. 065342-06 12/11
applied to the working electrode must be raised approximately 0.3 V when
switching from the “Ag” reference to the “pH” reference.
In acidic eluents, the reference potential of the pH half-cell is positive with
respect to the Ag/AgCl half-cell, and all applied potentials must be decreased
by 0.059 V per pH unit when switching from the “Ag” reference to the “pH”
reference.
Monitoring the ED Cell pH Readout
Monitoring the pH readout of a solution with a known composition lets you
detect any reference potential shift that may occur over time. This allows you
to determine when the
pH-Ag/AgCl reference electrode needs regenerating or
replacing, thus improving the reproducibility of your analyses. For
instructions on how to monitor the pH readout, see
Section 4.1.2 .
NOTE
Monitor the pH when the pH-Ag/AgCl reference electrode is
used in the Ag mode as well as in the pH mode.
Do not allow the pH-Ag/AgCl reference electrode to dry out. Make sure
that eluent is being pumped continuously through the cell at a low flow
rate (for example, 0.05 mL/min). If the cell will not be used for a short
time (less than 2 days), disconnect the tubing from the inlet and outlet
fittings and install fitting plugs. For longer shutdowns, remove the elec-
trode from the cell and store it in its storage cap filled with saturated
KCl solution. See
Section 6.4 for detailed storage instructions.