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Israeli Scientists Freeze Water By Warming It
ccktech writes "As reported by NPR and Chemistry world, the journal Science has a paper by David Ehre, Etay Lavert, Meir Lahav, and Igor Lubomirsky [note: abstract online; payment required to read the full paper] of Israel's Weizmann Institute, who have figured out a way to freeze pure water by warming it up. The trick is that pure water has different freezing points depending on the electrical charge of the surface it resides on. They found out that a negatively charged surface causes water to freeze at a lower temperature than a positively charged surface. By putting water on the pyroelectric material Lithium Tantalate, which has a negative charge when cooler but a positive change when warmer; water would remain a liquid down to -17 degrees C., and then freeze when the substrate and water were warmed up and the charge changed to positive, where water freezes at -7 degrees C."
Salt and anti-freeze just have typical freezing-point depression; there's no way to use them to produce a situation where water that is a stable liquid at one temperature will turn solid if you increase the temperature. The situation in this experiment is that water that's liquid at -17 C will freeze as you head it up towards -7 C.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
That's an old bar trick. It has to do with the co2 being released on pressure change. Nothing like the science these folks have described.
You missed the point. The neat thing is that water was liquid, and then they WARMED it, and it froze. It is just a gimmick, but it's not just that they managed to get it to freeze at a temperature below 0C. It's that, due to the interaction between temperature, charge, and the freezing point, they reversed the normal COLD-WARM SOLID-LIQUID order.
Slashdot headlines seem to do it now and then:
Canadian Scientists Regrow Teeth
French Scientists Link Higher BMI with Lower IQ
British Scientists Reverse Casimir Effect
German Physicists Claim Speed of Light Broken
Japanese Scientists Claim To Reconstruct Images From Brain Data
Italian Scientists Put Robot Spiders In Your Colon
etc.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
I don't find it particularly disturbing. I was pointing out the examples for the opposite reason--- to suggest that "[Nationality] Scientists" is not a particularly unusual phrase, contrary to the claims of the poster I was replying to.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
I thought pure water doesn't go solid, not until an impurity starts crystal formation that turns the water into a solid?
In many cases, the surface of the container has defects which can play that role.
Gravitation is a theory, not a fact.
Actually, liquid water already contains quite a lot of tetrahedral "crystalline" structures floating around amongst the other molecules. So it really shouldn't need anything external to crystallize around... it already has some of its own.
Not only is it not particularly hoppy, it has a pretty significant rice content. If anything, bud is hop-flavored rice alcohol. This being said, it's still my favorite mass market beer.
I think he was referring to the fact that it tastes like fizzy water with beer-like flavour, not the alcohol content. And Budweiser tastes pretty darned watery, even compared against other beers of the same type. Ales usually have a heavier taste to them, so it's not really fair to compare Budweiser against something like Guiness or Caledonian in terms of flavour. It is, however, fair to compare it against a good lager like Pilsner Urquell. Even when you compare it against a shitty lager, like Labatt Blue (which is also a pilsner, like Budweiser), Budweiser comes out on the bottom.
(and no, I'm not saying that Canadian beer sucks, just that some of the most popular Canadian beers suck. Namely, Labatt and Molson. If you want a good Canadian beer, try something like Steam Whistle, or Wellington. We don't export the good stuff. Similarly, I think the Australians are smart enough to export the shitty beers and keep the good stuff for themselves, as are the Dutch... think about that when you order a Fosters or a Heineken.)
Tantalum is non-toxic, but you know it doesn't really work like that. Sodium is explosive; chlorine is toxic; sodium chloride is tasty.
Still, as you say, lithium tantalate is going to be far too expensive for coating pipes.
There has been quite a bit of work put into different 'icecretes', as a matter of fact. Here are a few examples, although I'm sure there's more that I'm not even aware of:
http://www.globalsecurity.org/military/library/policy/army/fm/31-70/Ch6.htm
Skip down to para 6-8.c and 6-10.b
http://en.wikipedia.org/wiki/Pykrete and http://en.wikipedia.org/wiki/Project_Habakkuk
http://pisces.hilo.hawaii.edu/documents/VT-NIA-PISCESFinalReport.pdf
A *very* interesting paper on using lunar regolith icecrete for construction (among other topics)
-b
No offense, but I've stopped responding to AC's.
When you open it COs is released this causes the pressure to fall.
pV = nRT
So you did in fact cool it by opening it.
You could also supercool it I guess and shaking it a little when taking it out causes it to crystallize - but I'm having doubts about beer and beer bottles being pure enough to not crystallize out in the first place.
This is recent research. I believe you can find the article on Ars Technica right now.
Yeah, and if you pull a certain amount of vacuum on it, you can get water to do all of boil, liquefy and freeze at the same temperature. This is even without applying mechanical energy or kinky fields (electrostatic or magnetic) to coerce its behavior.
Caveat Emptor is not a business model.