Comment by boxed
8 hours ago
Because then it doesn't alter the side of the membrane where it does the reading (plus one minus one equals zero). That makes the measurement more accurate.
8 hours ago
Because then it doesn't alter the side of the membrane where it does the reading (plus one minus one equals zero). That makes the measurement more accurate.
Specifically, if you assume a partial pressure of Oxygen and of all other gases on the electrode-side of the diffusion membrane, then you'll only see a certain number of "ionization events" per time, and you're limited in how much electrical signal you get by how fast oxygen can diffuse across the membrane. This is likely driven by maintenance of a partial pressure within the membrane. However if you re-ionize the oxygen that you deionized, then the partial pressure is much closer to equilibrium, and therefore the partial pressures are only dependent on the amount of oxygen outside of the membrane instead of being dependent on both the ionization rate and the recovery rate through the membrane. It probably makes the calculation a lot faster and more closely dependent on the environmental presence of oxygen which is what you want.
You're not really making things clearer.
What does "adds back an oxygen molecule" mean?
It means you do an electrochemical reaction that releases an oxygen molecule, like the original explanation said. It doesn't really matter what reaction it is, but it could for example be electrolysis, where you split 2x H2O into 2x H2 and 1x O2.
The point is this reaction is reversible. In one direction, you end up with fewer O2 molecules than you had before. In the other direction, you end up with more.
That's an implementation detail no? Are you asking how to add an oxygen molecule, or how this makes the sensor better?
Yeah, how do you add the oxygen molecule, and how do you know when you have to do that?
Elaborate and you'll find the issue with this setup.
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