Difference between revisions of "Radon measurement with DIY track detectors"
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Inspecting the samples under the microscope. There are holes or bumps in different densities and with a size of about 3um of diameter. | Inspecting the samples under the microscope. There are holes or bumps in different densities and with a size of about 3um of diameter. | ||
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[[File:DVD.png|300px]] [[File:CR39_2.png|300px]] | [[File:DVD.png|300px]] [[File:CR39_2.png|300px]] | ||
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DVD sample and CR39 sample under the web cam microscope. (400x) | DVD sample and CR39 sample under the web cam microscope. (400x) | ||
Tried to look at the samples with the DVD scanning microscope. Looks nice: | Tried to look at the samples with the DVD scanning microscope. Looks nice: | ||
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[[File:LaserDumpAlpha1.png|300px]] [[File:LaserDumpAlpha2.png|300px]] | [[File:LaserDumpAlpha1.png|300px]] [[File:LaserDumpAlpha2.png|300px]] | ||
Revision as of 18:43, 28 November 2018
Radon: origin, health effects, measurements, Marco Silari, CERN:
Playing with Radioaktiviät - cool.
Alpha particles form the gas or liquid shoot holes in the plastic, then you develop it to make the hole bigger. Take CR-39 Plastic (from laser googles ?) etch it with 7M NaOH, 70°C for 5h ?
1 M NaOH is 40g
NaOH is commonly used to develop photo-resist when making DIY printed circuit boards... so we should have some in the lab.
PMMA/Acryl should work as well...
Can we use the DVD laser scanner to see the holes?
And could we use a DVD as detector material (Polycarbonat)? And how about modifying a DVD player to read the holes? And using old CDs or DVDs from a cellar to determine the radon concentration? Make it a community science project?
People have looked into this before: Application of polystyrene films for indoor radon dosimetry as SSNTD
Radon mapping by retrospective measurements – an approach based on CDs/DVDs
echt geil
How about Electrochemical etching or Ultrasonic etching?
First Experiments
Let's try and meet at SDG Solution Space in Geneva for "Open Hackuarium 228 "Sans les murs" #2, Spécial Genève"
Hmm... did not work. No traces.
Second Experiment
Let's try again.
Maybe we need to use ultrasonic bath or electrochemical etching?
Electrochemical etching with 15 kV AC/cm, 40 kHz.
Electrochemical etching studies of the CR-39 plastic
Getting the CR39 from ebay, it's cheap. (Look for "CR39 welding")
Put a piece of CR39 and a piece of delaminated DVD-R on an alpha source (Quantum Pendant), then 2 hours in 7M NaOh in an ultrasonic bath a 70-80°C.
The source produces about 2-5 big alpha impacts per cm2 per second.
And there seems to be something. One side of the plastic sample turned milky. The other side that was covered by a scotch tape during radiation (not during the etching) is clean.
Inspecting the samples under the microscope. There are holes or bumps in different densities and with a size of about 3um of diameter.
DVD sample and CR39 sample under the web cam microscope. (400x)
Tried to look at the samples with the DVD scanning microscope. Looks nice:
Links: