Okay, granted, the quantum-mechanic aspects of this are amazing, and the video is truly mesmerizing. But did you notice something else? The narrator is handling the liquid-nitrogen-cooled (-364 degrees F) puck with his bare hand!
@Electricaye... i wouldn't even know where to start. But the first application obviously would be a new kind of hair gel. Who would waste time and resources on something trivial like transportation, hover-boards or military applications?:)
Okay, granted, the quantum-mechanic aspects of this are amazing, and the video is truly mesmerizing. But did you notice something else? The narrator is handling the liquid-nitrogen-cooled (-364 degrees F) puck with his bare hand!
-Phil
Apparently it is appropriate to work without "protective" equipment when using liquid nitrogen.
The reason is the Leidenfrost effect. The LN2 droplets flash-evaporate when they hit bare skin, producing an insulating layer of gas, and prevents freezing damage. Assuming it's a quick spill, and not continous contact. Shoes, glove (including asbestos gloves), and any other clothing that confines the LN2, and cold gas *will* cause freezing.
I winced each time he touched as well. I think the Leidenfrost effect works with a liquid but this was a solid object at that temperature. I am actually shocked it didn't stick to him as it froze moisture on his skin.
I've experienced and been saved from a major burn from what I assume was the Leidenfrost effect...
Back when I was in my late teens I used an oxy-acetylene torch to cut off a few inch long piece of 1/2" by 3" steel.
Without thinking I bent down to pick it up from the floor as soon as it was cut, it just slipped out of my hand. I didn't feel any pain, just the distinct smell of burning flesh.
To my suprise I just had a layer of "dust" on my thumb and fingers where I touched it. My thought is that it vaporized the water in the top layer of skin and produced a barrier preventing further heat transfer.
ElectricAye
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Out of curiosity, how did you find this video?
A friend emailed it to me. Cool, huh? I especially like the locking feature.
I receive an electronics journal email each day and it had the article.
Stop messin with your hair and get busy on those room temperature superconductors! We need some new gadgets like that to drive around in.
-Phil
Sure, the first -20 degrees are a killer, but after that, it's all the same. Take my word for it.
-Phil
It doesn't happen right away. Geeeez!
Apparently it is appropriate to work without "protective" equipment when using liquid nitrogen.
From http://www.biotech.ufl.edu/EM/data/ln2.html
A more extreme example: http://www.popsci.com/diy/article/2010-08/cool-hand-theo
Back when I was in my late teens I used an oxy-acetylene torch to cut off a few inch long piece of 1/2" by 3" steel.
Without thinking I bent down to pick it up from the floor as soon as it was cut, it just slipped out of my hand. I didn't feel any pain, just the distinct smell of burning flesh.
To my suprise I just had a layer of "dust" on my thumb and fingers where I touched it. My thought is that it vaporized the water in the top layer of skin and produced a barrier preventing further heat transfer.
C.W.
-Tor