Re:At high pressures, potassium adopts a mix of crystalline ...
by rcthompson on Tuesday April 09, 2019 @11:19AM
(#19615523)
What they describe doesn't sound like a non-newtonian fluid, although it's possible that the atomic-scale behavior they described manifests non-newtonian behavior on a macroscopic scale.
Re:At high pressures, potassium adopts a mix of crystalline ...
by halfjew222 on Tuesday April 09, 2019 @11:15AM
(#19615472)
Love oobleck - really neat stuff.
From the article, it seems that what’s described is slightly different. While oobleck requires certain stimulation to achieve its states (standing still on Oobleck, you will sink; walking across oobleck, you’ll be fine) the potassium contraption described chemically appears to be a solid but is also actually melting.
Forgive me if I didn’t do a good job describing, but I felt the difference was worth pointing out. Perhaps it would be fair too to say that the potassium did require a little prodding at 20,000 an increase in pressure to that of earth.
Re:At high pressures, potassium adopts a mix of crystalline ...
by dwighttk on Tuesday April 09, 2019 @11:15AM
(#19615478)
One new thing is that this is a single element, not a combination of molecules.
Re:At high pressures, potassium adopts a mix of crystalline ...
by empath75 on Tuesday April 09, 2019 @11:16AM
(#19615485)
This is not a non-newtonian fluid.
Re:At high pressures, potassium adopts a mix of crystalline ...
by derekp7 on Tuesday April 09, 2019 @11:18AM
(#19615513)
I wonder if something like that would work in a ballistics armor application?
An inexpensive, non-toxic example of a non-Newtonian fluid is a suspension of starch (e.g. cornstarch) in water, sometimes called "oobleck", "ooze", or "magic mud" (1 part of water to 1.5–2 parts of corn starch). The name "oobleck" is derived from the Dr. Seuss book Bartholomew and the Oobleck.
Because of its properties, oobleck is often used in demonstrations that exhibit its unusual behavior. A person may walk on a large tub of oobleck without sinking due to its shear thickening properties, as long as the individual moves quickly enough to provide enough force with each step to cause the thickening. Also, if oobleck is placed on a large subwoofer driven at a sufficiently high volume, it will thicken and form standing waves in response to low frequency sound waves from the speaker. If a person were to punch or hit oobleck, it would thicken and act like a solid. After the blow, the oobleck will go back to its thin liquid like state.