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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."
But I was expecting something along the lines of "Researchers manage to make water freeze at greater than 0C," instead of "Researchers manage to make water freeze below normal freezing temperature."
Haven't they ever heard of salt? Or Anti-freeze?
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
That does sound really cool, even as a fundamental research, but are there some cool real-world applications I'm not thinking of?
It's not the fall that kills you. It's the sudden stop at the end. -Douglas Adams
It's not quite Hell, but it's an impressive step in that direction...
By reading the title only, I thought the overflow-bug of water was finally found.
I wonder if it's feasible to coat this material on the inside of water pipes, to prevent them freezing in winter?
An Australian from Mitta Mitta who failed a dowsing test claimed that he only failed because the water was "electrically charged wrong".
http://video.google.com/videoplay?docid=4694530584288972114
I don't remember the science story yesterday Physicists Discover How To Teleport Energy being called Japanese Physicists Discover How To Teleport Energy. Is the fact these scientists are Israeli title worthy?
When I put a beer in the freezer too long but not that long, when I take it out of the freezer, I can see it is pretty 100% liquid inside the bottle. Now, taking it out of the freezer makes it warmer and opening it even warmer due to air circulation inside the bottle.
Well, when I open it, it turns to ice so I make my beer freeze by making it warmer so nothing new here ;--))))
Very seriously, I swear this is true but I understand it could be due to other factors that the ones described in TFA like pressure inside the bottle but I thought it would interesting to mention anyway.
Haven't anybody else seen their beer freeze in their hand while opening it just after it has been in the freezer although it was in a liquid state when they actually took it out of the freezer ?
Everything I write is lies, read between the lines.
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.
One of these guys managed to turn water into wine 2000 years ago...
You clearly must be an American, since you compare beer to water. Over here in the old world, we know there is a difference by the taste for one.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
He must be negatively charged (thus keeping water a liquid on or in him) and then the moment he "releases" it, it freezes!
Could there be some sort of industrial application for this, like ice-making where you have a jet of "liquid" water (because it is kept in a negatively charged apparatus) but upon contact with something, loses its charge and freezes? How about rapid construction of ice sculptures? Just like spray on concrete.
I even seem to remember someone in WWII proposing making giant pontoons/floating islands out of ice and hay.
How about in Antarctica/on Mars using it for rapid construction of ice domes? Once it solidifies it won't melt.
This is going to make a better Martini how, exactly?
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
and warm at the same time... Being capable of controlling freezing point of water with an electric field could have very interesting applications in automotive and building industry.
Good beer is NOT about the amount of alcohol, it is about the flavor. If it has low alcohol, you just can drink more of it. Granted, the better tasting beers tend to have high alcohol content, but I am sure that is just a coincidence. As is the fact that my new driving license has "revoked" pre-stamped across it.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
Turning ice into water by cooling it?
In any direction, changing state (or prevent that change) not using plain heat, but just charging electrically could make some applications more energy efficient.
Supercooled water will freeze with just about any trigger. The precise mechanism of this is kind of neat, but as an effect, it's not terribly surprising.
No, it's more like the realization that Canada is south of Detroit.
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Yes, I have. I consider it one of the crowning achievements of my life. Beer at -4 degrees C is a wonderful, wonderful thing in an Australian summer.
Testing with a digital thermometer was fun too. If the beer was too cold, dipping the tip of the probe into the beer is enough to start a cascade of freezing that blooms down through the whole bottle in about a second. Interesting phenomena to observe. But a waste of beer.
With practice, I got the method worked out. Slow and careful is the key. Higher alcohol beers work better.
You could make one heck of a freeze gun with this technology... spray things and they freeze
Hmm, water ice that is stable at a higher temperature than liquid water? Can anyone say ice-9?
Yes, but it's due to the pressure changes and release of dissolved CO2. :-)
No, it's more like the realization that Canada is south of Detroit.
I need a global map with the lettering right side up.
They are all taking lessons from KDawson?
Hey KID! Yeah you, get the fuck off my lawn!
It sounds like it freezes due to the change in charge, not because the water warms up. It's freezing in *spite* of the water warming. It's like they are just chasing the freezing point around.
You get the same effect when opening a highly chilled bottle of soda. It starts to freeze due to the release of carbonation, although the pressure change might come into play as well.
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.
when she saves me money by spending it.
So, does water absorb/release 334 kJ/kg when it thaws/freezes due to this change in charge? If so, we may have some interesting applications in the area of refrigeration, heat engines, etc.
Have gnu, will travel.
Water needs to reach the correct temperature and then have something trigger the phase transition.
In other words:
The crystallization has to start somewhere. Imperfections in the surface or impurities supply this. If you have very pure water and a "perfect" container, the lack of a starting point for crystallization can delay the phase transition by quite a bit.
(Then you get YouTube videos showing flash freezing of water bottles!/i))
Sure, I hinted about this in my post...
But you still just gave me a great idea: I will design a beer based air conditioner ( air cooler ) and sell it/publish it on sites similar to engadget ;-)))
Put in 4 cases of 24 and have some mechanism opening them one by one coupled with a fan and I am done ;-)
First on my list: Buy 4 cases of 24...
half an hour later:
Done...
one hour later:
Second on the list: Funny, I don't remember now...
Everything I write is lies, read between the lines.
So in summary: It's interesting that the polarity of the charge of a container drastically affects the freezing point. It's quite a bit less interesting that by using a fancy container which alters its charge you can get water to freeze when it's warmed. (That's a bit more like a parlor trick though - it's not really the warming that's the point, it's the change of charge.)
What would be really interesting to know is WHY this happens, i.e. the underlying physics that casue this effect. Also, is this phenomenon isolated to water or are there other liquids with similar properies?
Do you know how air is liquefied and then separated into N2 and O2?
I've also seen this happen with regularity - at work we sometimes crack a beer after hours, my boss likes to keep his cube fridge hell-frozen-overishly cold. So perfectly liquid beers (can or bottle) from the top shelf often freeze within 20 seconds after opening. He swears by the belief that giving the can a good hard squeeze for several seconds prior to opening reduces the chance of it freezing, but nobody has yet come up with a believable theory as to why that would be. Guesses so far are that the applying of warm hands boosts the temperature just enough, or that the final squeeze helps compress any stray bubbles back into solution and thus eliminate possible nucleation points. Personally, I'm just amused to keep mine a bit warmer and watch a handful of MS and PhDs arguing over why their beer freezes.
Caveat Emptor is not a business model.
First of all, you wouldn't put REAL beer in a freezer. You must mean what we in the UK call "lager".
Some highly filtered lagers and "lite" beers can readily be supercooled in a freezer. When removed, they have not solidified since there are no nucleation sites available to them. When opened, the CO2 bubbles will act as nucleation sites and freezing will occur rapidly, producing dendrites of ice in all directions. The same effect can be initiated by tapping the unopened bottle SHARPLY (without breaking it!) on a convenient surface. It's a handy party trick: offer a supercooled lager to someone you don't like and watch them [not] drink it.
This is similar to the what happens with sodium acetate (used in re-usable hand warmers and such) which can't 'remember' how to crystallize until provided with a seed (the button trigger in a warmer) and then gives off heat as it crystallizes.
http://en.wikipedia.org/wiki/Sodium_acetate#Heating_pad