5 Strangest Materials

MattSparkes writes to tell us that NewScientist recently posted a quick look at five interesting materials with some very strange properties. There are liquids you can walk on, liquids that will escape containers by creeping up the sides, and magnetic liquids that can easily show you the shape of magnetic fields. The story also offers video links to display some of more amazing properties described.

Magnetic Fluid

[sporkme]

4. Ferrofluids - magnetic fluids that can look spectacular. They're made from nanoscale magnetic particles suspended in a liquid. The spectacular sculpture in the video below is made using a ferrofluid and electromagnets.

You can get this stuff from United Nuclear [unitednuclear.com] (about 2/3 of the way down the page, sorry no anchors), as well as some fun looking "super magnets" and some radioactive ores.

When I read about the fluid that can flow up the sides of a container, all I could think about was THE BLOB!

Slashdotted

[RAMMS+EIN]

Unfortunately, it does not include the mysterious liquid that prevents servers from being slashdotted.

Coral cache link [nyud.net]

Re:What? no mention of silly putty!?

[palndrumm]

From TFA:
1. Dilatants - fluids that get more solid when stressed.

That pretty much covers silly putty, doesn't it?

They forgot Aerogel

[Anonymous Coward]

Aerogel [wikipedia.org] is a low-density solid-state material derived from gel in which the liquid component of the gel has been replaced with gas. The result is an extremely low density solid with several remarkable properties, most notably its effectiveness as an insulator. It is nicknamed frozen smoke, solid smoke or blue smoke due to its semi-transparent nature and the way light scatters in the material; however, it feels like extruded polystyrene to the touch.

Re:I have one for you

[dgatwood]

I would like to nominate whatever the hell Wonder Bread is made from.

I believe that would be high fructose corn syrup. Yes. Mostly high fructose corn syrup.

Re:What? no mention of silly putty!?

[Em Adespoton]

Actually, no; Silly Putty expands when stressed, it doesn't get more solid.

I've always known dilatants as Newtonian Solids (for instance, cornstarch mixed with water, which you can sink your hand into, but which can also withstand the force of a sledgehammer [as can your hand if it's submersed at the time]).

Re:Hammer, Feather, Freefall on the Moon: Revisite

[Mattcelt]

That's ok, David Scott did it for him:
http://www.hq.nasa.gov/alsj/a15/a15.clsout3.html [nasa.gov]

So what you're saying is while there's a theoretical difference between the impact timings, the practical effect likely couldn't be measured. Makes sense.

Re:One More I would inlcude: Plutonium

[whitehatlurker]

Wikipedia [wikipedia.org] has a nicer version [wikipedia.org] of the same diagram. It appears that only the delta phase (or delta prime phase) exhibits this expansion on cooling phenomena.

Re:I have one for you

[CosmeticLobotamy]

I have a feeling I'm missing a reference to something, but in case I'm not, Wonder Bread isn't that bad. It's 60 calories a slice. 70 is about average for white bread. Most whole wheat breads are around 90. The best you can buy around here is 35, and it tastes like recycled toilet paper that came out too moist and delicious so they ran a hairdryer over it for a week. If you're trying to be less of one of those bloated lazy crap sacks, switching to Wonder Bread isn't a bad place to start.

Re:Superfluid temperatures

[shimage]

My recollection was that it (the HeI/HeII phase transition) was in the neighborhood of 2.2 K. Now, you can say, "that's pretty close to 5 K", but keep in mind that at 1 atm, the boiling point is just over 4 K, so 0–5 K covers all of hydrogen's interesting low-T behavior.

Re:Superfluid temperatures

[Khashishi]

It is possible to have negative temperatures under certain circumstances, using the thermodynamic definition of temperature, but these negative temperatures are actually hotter than any positive temperature. (Positive) absolute zero is still the coldest something can be, while negative absolute zero is the hottest anything can possibly be. Negative temperatures are only possible in a system where the number of quantum states available decreases as energy is added to the system.

Re:Superfluid temperatures

[Idarubicin]

Funnily enough, I was just bitching about scientific faux pas in the mainstream media, but New Scientist?

Dude, have you seen New Scientist lately? Their cover story a few months ago was a levitation device for flying cars. Which would have been great, if the basic operating principle weren't one that could have been debunked by a sharp high school student. Lo, behold the mighty EmDrive [wikipedia.org].

New Scientist's response [newscientist.com] is just embarrasing. From editor Jeremy Webb (emphasis added):

"It is a fair criticism that New Scientist did not make clear enough how controversial Roger Shawyer's engine is. We should have made more explicit where it apparently contravenes the laws of nature and reported that several physicists declined to comment on the device because they thought it too contentious.

But should New Scientist should have covered this story at all? The answer is a resounding yes..."

New Scientist is fun to read, but it's definitely not a good idea to mistake it as a source of solid science reporting.

Re:What? no mention of silly putty!?

[Foehg]

I believe you mean 'non-Newtonian'.

Oh, and "Slow down, cowboy!"

Re:Superfluid temperatures

[Mursk]

You're correct. 5 K is when the Helium becomes (ordinary) liquid. It becomes a superfluid at ~2 K. Guess my Google search was a bit too quick. ;)

Re:why are the only interesting materials only flu

[scottv67]

They don't make it, they sell it. The guy that runs United Nuclear works at Los Alamos, and has for years, and has contacts that get him some scraps that he can sell.

Bob Lazar used to work at Area 51. I'm sure he has contacts who can make practically anything. It's a safe bet that only the "tame" stuff shows up in the United Nuclear catalog...

Re:Water comes to mind

[BigBlockMopar]

Yeah, and it self-dissociates in its liquid state - hence pH, easy ionization required for cell behavior, etc. As I stated in an earlier post, it's weird stuff, common and "familiar" or not.

Re:Hey retard

[Anonymous Coward]

Please read what the GP posted again.

According to TFA, "To make a superfluid you must cool helium down to a couple of a degrees below zero - not one to try at home."

It doesn't state anything about using helium to cool anything. It does mention cooling helium until it becomes a superfluid, which occurs just above absolute zero. The scale is implied, unless you know of a scale that has 0 just above the temperature in which helium becomes a superfluid.