Cleber Borges

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  1. Hello @Andras ... Very cool your results ... This case study is very interesting! Have you considered putting all this information on a blog too? (It can be an inspiration and starting point for others).
  2. Hello @Andras ... I think bubble formation is critical ... 1- Is CO2 forming? 2 - Just some other gas coming out? 3 - Yes, temperature is a critical parameter in measurements that require a lot of accuracy ... But I don't know how much temperature variation can affect a preliminary study that doesn't need as much precision and accuracy. Cleaning the electrodes I think is a good idea ... It would be nice to check how much influence on the results ...
  3. Hello @Andras ... Actually, two parallel plates are enough as electrodes ... But always make sure that they are well fixed and constant as any change in geometry adjustment will cause a lot of variation in measurement. The arrangement would only need more sophistication if the electrode itself developed a chemical potential at its interface! Which is not the case here ... So I think your scheme is satisfactory. [ 1 ] I would like to know the results with your yeasts ... if you can post the results. Very good to see a case study. Thank you very much Cleber [ 1 ] - p
  4. Hello @Andras ... Could you show how your electrode scheme looks? I think it is also geometry / electrode setup is a very important parameter. Very cool the results of your experiments ... In electrochemical impedance spectroscopy (EIS), I see that the voltage amplitudes are much smaller than you are using ... In general, the articles show that they are 100mV amplitudes due to problems with linearities in Nerst's law ... Have you tested at lower amplitudes? Thank you very much. Best regards, Cleber
  5. hello @Andras ... My IA board (impedance analyzer) arrived a few days ago, but I did not even test it ... But now I have the AI board in my hands. Thanks for your attention. The IA board does not allow a reference electrode (RE) such as figure-item B. Such a scheme would be to not pass current between the working electrode (WE) and a reference electrode (RE). It would be to measure more accurately and discount several other effects in a more automated way. This scheme is not necessarily mandatory. You can use the scheme of just two electrodes as you mention. I am a chemist
  6. @Andras I ordered the IA card and it took six months to arrive in Brazil. (Digilent-USA did not want to sell me direct for having representatives in Brazil) ... So I left the project temporarily 😞 I'm sorry you can not contribute information Cleber
  7. Hello @attila, Good Morning, I imagined that using the reference resistors (such as the impedance analyzer extension board) could have been used the I-V method, since it would be easy to calculate the current value (I) ... But, given your explanation, I understand that the AI tool still uses the same method: Transfer Function Analysis (or the same as FRA - Frequency Response Analysis) ... [I needed this information to report] Thank you very much for your response and dedicated attention to this issue. Cleber Borges
  8. Hello @attila Thank you for your consideration and for your response. My question is more about the theory itself. Since I have the Magnitude and Phase experimental measure, the rest of the properties are reasonably easy to calculate by a CAD (algebra software) My concern is to know what are the real limitations involved in measuring when I ask about fundamental differences.
  9. Hello everyone, Reading about the EIS area - Electrochemcical Impedance Spectroscopy - I found that currently commercial potentiostats implement Impedance analysis by the method: FRA - Frequency Response Analyzer, also referred to as Transfer Function Analysis. As far as I understand, this method would be the same as the one implemented by the Network Analyzer tool in AD2 (am I right? 🙂 ), since in its description it consists of: "The Network Analyzer is used to analyze transfer functions (the ratio between an output function and an input function)" If I can have the Impedance
  10. Hi @attila, Is there any future revision possibilities for the IA-adapter to be able to contemplate these three electrodes? Since minimizing the connectors, wires, welding ... And always using the same precision resistors greatly improve the accuracy of measurements. It would be an interesting platform for use in electrochemistry with the use of 3 electrodes. thanks Cleber Borges ps.: (here in Brazil I never found resistor 0.1% to buy) :-(
  11. Hi @attila, Good Morning! As far as I understand, this implementation: W1-C1P-DUT-C1N-C2-R-GND was tailor-made for the example I mentioned! Thank you very much because it will be much easier to do chemistry tests. In general, in Chemistry, the frequencies of ~ 1kHz - 100kHz are more usual and values of ~ nanofarad Thanks :-) Cleber Borges
  12. Many thanks @attila, But if you say you tested in the differential configuration, I will not try to do it because I do not have much experience or material for these tests. And logically for the use of 3 electrodes I would necessarily need to use differential mode. In any case, it would be very useful for electrochemistry if it worked.
  13. Dear all, Good afternoon! In electrochemistry, a system of 3 electrodes is used to: 1 - measure the Potential (V) between the Working Electrode (WE) and the Reference Electrode (RE) 2 - measure the current (i) between the Working Electrode (WE) and the Counter-Electrode (CE) The RE is constructed so that no electric current must flow between WE and RE. My question is: If I use the schematic of figure B, the tool: Impedance Analyzer, implemented in Waveform, will it use the potential difference of the channels of the Scope1 (+) port and the (-) port? My goal is