WPI APOLLO 4000, Инструкция по эксплуатации

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APOLLO 4000
NITRIC OXIDE DETECTION
WORLD PRECISION INSTRUMENTS C-4
5.
Place the stand (and water bath if appropriate) on the magnetic stirrer, and
turn on the stirrer so that the bar is stirring at a moderate rate.
6. Secure the ISO-NO sensor in an electrode holder or micromanipulator (or use
one of the septums included with the start-up kit). Do not push the sensor
tip through the hole — slide the elctrode through the sliced side
of the septum. Carefully lower the sensor into the vial sealing the opening
with the septum. The sensor tip should be immersed about 2-3 mm into the
solution, and should not be in contact with stir bar. Be very careful when
inserting the sensor not to make contact between the cap and/
or bottom of the jar with the tip of the sensor. This could
damage the membrane of the sensor.
7. Wait until the current on the display becomes stable again before continuing.
This may take several minutes if the sensor has undergone a large temperature
change.
8. If you feel it is necessary to degas solution #1 prior to calibration, this can be
done by inserting one of the long stainless steel needles included with the
calibration kit through the septum so that the tip is in the solution. Attach the
needle through appropriate tubing to a source of pure argon gas (nitrogen
may also be used). Insert one of the short needles included with the kit
through the septum such that the needle tip is clearly exposed ( not in the
solution ) inside the vial. The small needle allows gas to escape, thereby
avoiding a buildup of pressure. Purge the solution at low pressure (5 psi or
less) for 15 minutes.
9. Once purging is complete and the gas source is turned off, remove the purging
and pressure relief needles.
10. One should allow a few minutes for the temperature to equilibrate with the water
bath again since purging with the gas may have changed the temperature.
11. Once the current has achieved a stable value, record this value.
12. Generally, it is not necessarry to pre-purge the calibration solution, since the NO
decays only very slowly in this solution.