
UCLA researchers have produced X-rays by simply unrolling Scotch tape (2008) - mpweiher
https://www.nytimes.com/2008/10/28/science/28xray.html
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Nanite
They went on an founded a startup called Tribogenics, raised a total of about
$20M over the years (among others from Nikon and Founders Fund), They worked
on developing lower cost portable XRF scanners, but apparently went out of
business earlier this year. From what I've heard the tech didn't work quite as
well as they had hoped and their market fit wasn't that great.

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smegger001
I wonder if the invisible electrostatic wall at the 3m tape plant is related
to this?
[http://amasci.com/weird/unusual/e-wall.html](http://amasci.com/weird/unusual/e-wall.html)

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Spare_account
Bringing up this story usually results in an argument about whether or not it
is even true.

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bkraz
I made a video in which I tried to replicate this effect. It didn't work.
Unrolling tape will definitely create a high potential difference, which will
accelerate electrons in a vacuum. For medically relevant levels of x-rays, the
potential needs to be 20KV at least, and about 100 microamps at minimum. This
is 2 watts. The triboelectric effect is not very efficient, so imagine you
have to get 20 watts into the unrolling tape. The adhesive will separate
before it will accept this power level. Anyway, I was thinking of
revisiting...

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bkraz
[https://youtu.be/QLvzvwQFKfI](https://youtu.be/QLvzvwQFKfI)

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mchahn
This is most interesting use of scotch tape since graphene was first observed.

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oever
Article is from 2008.

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stuaxo
Indeed, did anything else happen after this?

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newman8r
It was also discovered that the scotch tape method emits radiation in the
terahertz range (2009)
[https://www.ncbi.nlm.nih.gov/pubmed/19823546](https://www.ncbi.nlm.nih.gov/pubmed/19823546)

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raverbashing
Any explanations of why doing this to scotch tape releases such energetic
particles? (ok, THz not so much, but x-rays are energetic)

~~~
newman8r
Looks like it's due to triboelectric-related effects
[https://en.wikipedia.org/wiki/Triboelectric_effect](https://en.wikipedia.org/wiki/Triboelectric_effect)

so with the tape I'd assume it's due to the friction from unraveling the
sticky side from the non-sticky side

also related to
[https://en.wikipedia.org/wiki/Triboluminescence](https://en.wikipedia.org/wiki/Triboluminescence)
which the scotch tape demonstrates as well

