Ultra Low Temperature Experiment: LN2 & AXP
 

Great read, good pictures, nice results!

"With the whole beginning of the project, one wished to create a new cooling based on a relaxation of Joule with air or gas nitrogen contained in the large bottles with 200 bar. It is a little this kind of thing which is used in last stage of a cryogenic installation intended to approach very close to the absolute zero (-273.15 °C) by slackening helium. The brutal relaxation of gas high pressure through opening gauged in a cavity maintained under a low pressure would have made it possible to descend gas at very low temperature (towards its temperature of liquefaction)."

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