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Hi,
I assembled a MFC (MFC1) on 12/26/14 and it started blinking on 12/27/14 at night. Next day the power was at 3 micro-watts and I thought my experiment was going very well. The next day however the power went down to 2 micro-watts. The following day it stopped blinking and has not blinked ever since.
I assembled a second MFC (MFC2) on 12/27/14. This is the one I intend to add urine to later and use the MFC1 as control. MFC2 has not blinked yet.
What should I do with MFC1? Should I redo it? Why would it blink so early? Why would it stop? Will it blink again?
My project is due on Jan 25th and I am starting to worry about the success of this project.
Thanks for your help.
MWE
powered by pee: using urine in a MFC
Moderators: AmyCowen, kgudger, bfinio, MadelineB, Moderators
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Student1
- Posts: 6
- Joined: Tue Dec 30, 2014 10:21 am
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- Project Question: MFC with and without urine
- Project Due Date: Jan 25th 2015
- Project Status: I am conducting my experiment
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SciB
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Re: powered by pee: using urine in a MFC
Hi MWE,
Did you try measuring the voltage on MFC2? Also, you could take the lid with the hacker board and LED from MFC1 because you know it works and try it on MFC2. Equipment failure is always a possibility.
The only other thing I can think of is that somehow oxygen is getting to the anode and blocking the current flow. This could also explain why MFC1 stopped producing current. Where did you get the soil to make the mud? It should not have a lot of particles that could create air spaces. Also, you don’t want any pesticide residues or run-off from something like oil or solvents that could be toxic to the soil bacteria. One other thing I just thought of. Did you use distilled water when you made the mud? Chlorinated water can harm the soil bacteria.
You can take the cells apart and put in some fresh mud from a different location.
I hope this helps to solve the problem, but if not I would submit your question to the Life-Sciences forum. They have experts who may know more about the bacterial side of the MFC than experts in physics.
Good luck!
Sybee
Did you try measuring the voltage on MFC2? Also, you could take the lid with the hacker board and LED from MFC1 because you know it works and try it on MFC2. Equipment failure is always a possibility.
The only other thing I can think of is that somehow oxygen is getting to the anode and blocking the current flow. This could also explain why MFC1 stopped producing current. Where did you get the soil to make the mud? It should not have a lot of particles that could create air spaces. Also, you don’t want any pesticide residues or run-off from something like oil or solvents that could be toxic to the soil bacteria. One other thing I just thought of. Did you use distilled water when you made the mud? Chlorinated water can harm the soil bacteria.
You can take the cells apart and put in some fresh mud from a different location.
I hope this helps to solve the problem, but if not I would submit your question to the Life-Sciences forum. They have experts who may know more about the bacterial side of the MFC than experts in physics.
Good luck!
Sybee
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bradleyshanrock-solberg
- Former Expert
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Re: powered by pee: using urine in a MFC
Just to add another concern here...
It's tough to control the properties of urine (it is different from person to person, or between people and animal, indeed a large amount of diagnostic work in early medicine was based on looking at urine samples. Even with one individual, it can vary based on what you ate or drank recently).
It's tough to control the properties of urine (it is different from person to person, or between people and animal, indeed a large amount of diagnostic work in early medicine was based on looking at urine samples. Even with one individual, it can vary based on what you ate or drank recently).
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Student1
- Posts: 6
- Joined: Tue Dec 30, 2014 10:21 am
- Occupation: student
- Project Question: MFC with and without urine
- Project Due Date: Jan 25th 2015
- Project Status: I am conducting my experiment
Re: powered by pee: using urine in a MFC
very true, maybe that is why salt is used more commonly…
Thanks for your help.
Thanks for your help.
-
Student1
- Posts: 6
- Joined: Tue Dec 30, 2014 10:21 am
- Occupation: student
- Project Question: MFC with and without urine
- Project Due Date: Jan 25th 2015
- Project Status: I am conducting my experiment
Re: powered by pee: using urine in a MFC
Anybody has any suggestions on how to display data for this project? I have different resistors with different voltage and power measurement over many days for two diferent MFCs. Not sure what to compare and what to show in my charts, highest power per day, powers across same resistor, to compare or not the two MFCs on the same graph…. to complicate it even more, I will have new data after adding urine. I also have blinks per second to display. Please suggest ways to organize this data in an easy way to interpret.
thanks.
MWE
thanks.
MWE
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bradleyshanrock-solberg
- Former Expert
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Research in Traffic and Ceramic Composites
25 years doing IT, various roles, for multinational manufacturing company - Project Due Date: n/a
- Project Status: Not applicable
Re: powered by pee: using urine in a MFC
This answer is probably not going to be as specific as you'd like, but this is a good general rule for presenting data of any kind.
1. What story are you trying to tell? The data you present should tie into the Question that is driving your experiments, and show whether or not the expected outcomes occurred.
2. Remember that a graph can only handle two dimensions. If you have data that needs to show more than how two thing relate to each other, you will likely need more than one graph.
3. Raw data is good to have as backup to show your work, but is not an effective communication tool by itself. People are better at understanding images. Also different types of graphs are more effective for different types of communication. Most science fair projects tend to lean on Bar graphs, which are good for showing visually how results for two different data sets compare (eg, 3 trials done one way, compared to 3 trials with a single independnet variable change). Changes over time are often better expressed with line graphs (eg, showing petri mold growth over the course of the experiment, each line representing one sample, which might or might not have a variable change). Pie charts are best at showing changes within a population that didn't change, but can be fairly good at showing data with multiple "flavors" between two or more experimental setups. For example, you might have a pie chart showing distibution of data with salt water, and how it varied with urine, if the data is too complex to easily be done with a typical bar chart.
So go back to your question. Think about what in your data shows that you've answered your question and proved or disproved your hypothesis. Then try to come up with a way of showing it visually via graphs/charts that will help somebody not familiar with all the context understand what you did.
1. What story are you trying to tell? The data you present should tie into the Question that is driving your experiments, and show whether or not the expected outcomes occurred.
2. Remember that a graph can only handle two dimensions. If you have data that needs to show more than how two thing relate to each other, you will likely need more than one graph.
3. Raw data is good to have as backup to show your work, but is not an effective communication tool by itself. People are better at understanding images. Also different types of graphs are more effective for different types of communication. Most science fair projects tend to lean on Bar graphs, which are good for showing visually how results for two different data sets compare (eg, 3 trials done one way, compared to 3 trials with a single independnet variable change). Changes over time are often better expressed with line graphs (eg, showing petri mold growth over the course of the experiment, each line representing one sample, which might or might not have a variable change). Pie charts are best at showing changes within a population that didn't change, but can be fairly good at showing data with multiple "flavors" between two or more experimental setups. For example, you might have a pie chart showing distibution of data with salt water, and how it varied with urine, if the data is too complex to easily be done with a typical bar chart.
So go back to your question. Think about what in your data shows that you've answered your question and proved or disproved your hypothesis. Then try to come up with a way of showing it visually via graphs/charts that will help somebody not familiar with all the context understand what you did.