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Title: He and baloons
Date: 05-03-2021
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Hi there!
Last day before weekend - and maybe last day of lessons in presence.
This morning, during the NMR class, my professor told us about the role of
helium to obtain a superconducting coil.
Small digression: although helium is the second most abundant element in the
universe, it's presence in the Earth's atmosphere only in trace amount (about
5 ppm), since it's too light too be retained by gravity. The reserves of this
element are running out. Some estimates predict its exhaustion in about 20
years.
In addition to the cool uses that chemists make of it, this liquefied gas is
used in the medical-diagnostic field for the MRI (Magnetic Resonance Imaging).
Think about it every time you see kids with ballons: that helium is lost
forever.

21.12 UTC+1 update
I've just received an email from my university: all lessons are suspended until
20-03-21. Fuck.

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