Gamry Instruments MultiPort, Руководство оператора

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Customizing Your Cell--Addition of Corrosive Agents
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Customizing Your Cell
The MultiPort was designed to have options available even while fully accommodating the ASTM G5 standard.
There are seven total ports and only three or four necessary for most experiments (five or six for full ASTM G5
compliance with opposed counter electrodes and a thermometer or temperature probe). With anywhere from
one to four spare access ports and a two-piece cell design, customization options are myriad. Some common
modifications to experiments are mentioned below.
Addition of Corrosive Agents
In many experiments, you record a baseline curve before you add a vital reactant to the cell. You then add that
reactant, stir the cell, then record another curve. Many of Ga
mry’s analysis packages allow you to subtract the
baseline curve from the data curve. The resulting curve shows only electrochemistry related to this reactant.
Another common use for added reactant is current-versus-concentration studies.
In either case the additional ports allow you to make changes to the solution easily.
Temperature Sensing and Control
The rate of almost all chemical reactions is strongly temperature-dependent. For this reason, you might want to
either measure or control the temperature of your cell.
Many thermometers will fit the standard bushing for a #7 thread. This is an convenient way to add temperature
measurement to your system.
In many cases, temperature must be controlled, not measured. One way to do this is:
1. Purchase the jacketed option for the corrosion cell. This is a special cell body that allows a flowing
temperature-transfer fluid to encase the cell.
2. Plumb the jacket on the cell to a recirculating constant-temperature bath.
3. If the bath offers remote temperature sensing, place a sensor in the spare port of the cell. This may
require purchase of another option (for example an RTD-to-14/20-port adapter).
In some cases, Gamry’s software supports setting automatically the temperature. Add the controlled
temperature to the expe riment’s Setup window, and the software controls the temperature bath via an RS-232
port. In other cases, a modified script is required.
Addition of a pH Electrode
Another possible use for the space port is addition of a pH electrode. An adapter is required.
Getting a Stir Bar into the Cell
If you want to magnetically stir, and you forget to add a stir bar to your cell, you can add it using the spare port.