Supercooling

(redirected from Super-cool)

supercooling

[¦sü·pər′kül·iŋ]
(thermodynamics)
Cooling of a substance below the temperature at which a change of state would ordinarily take place without such a change of state occurring, for example, the cooling of a liquid below its freezing point without freezing taking place; this results in a metastable state.

Supercooling

 

cooling of matter to temperatures below those of equilibrium phase transition that brings the matter to a new state of aggregation, or another crystalline modification that does not result in a phase transition. A supercooled material is in a state of metastable equilibrium.

The phase transitions that are associated with loss of heat— condensation, crystallization, and polymorphic transformations —usually involve supercooling in their initial stages; the supercooling helps generate nuclei of the new phase in the form of tiny droplets or crystallites. It is difficult to form nuclei at the phase-transition temperature because the nuclei feature higher pressure or solubility and thus cannot be in equilibrium with the initial phase at this temperature. Under conditions where the generation and growth of nuclei of a new phase are inhibited, for example, during recrystallization of a solid and during crystallization of a highly viscous liquid, deep supercooling can be used to obtain a practically stable phase whose internal structure resembles that of phases at higher temperatures. This procedure is the basis for steel-quenching processes and for the production of glass. The degree to which water vapor is supercooled in the atmosphere determines whether precipitation will occur in the form of rain, snow, or hail.

References in periodicals archive ?
SUPER-COOL Kilcoo will cross swords with old adversaries Crossmaglen in the Ulster semi-final after a 19 point rout yesterday.
Sweatshirts, T-shirts and super-cool trainers are on offer in stores now, and start PS30.
THIS dish is super-cool and would be wonderful on its own just as an arty object, or on a sideboard in the hall to throw your keys into as you walk through the door.
Charles' Saturday night soul and funk show on BBC 6 Music is required listening for people of a certain age - and a few super-cool young 'uns too.
For a sequel, it's been a long time coming, but everything from the crisp HD visuals and super-cool audio to the careful balancing of strategy, discovery and laugh-out-loud moments of pure fantasy combine to deliver one of the Wii U's finest moments to date.
In a move which makes pals Kanye West and Kim Kardashian look like paupers in comparison, the super-cool suite at the Brooklyn Nets ground in New York apparently costs $1 million a year to rent while Jay-Z watches a game or performs to his home crowd.
Given a super-cool ride from Graham Lee, The Tiger sluiced through the pack and pulled right away in the straight to beat his rivals senseless by four-and-a-half lengths and more.
He's super-cool, relaxed, chilled and very honest, which I love.
Insider hears the Liverpudlian X Factor star was out dining in Scarpetta Italian eaterie (very posh, $28 for pasta dontcha know) on the edge of the city's super-cool Meat Packing District when she noticed a familiar face at the next table.
Ryan Gosling is brilliant as the super-cool Driver.
Opened in Liverpool One last night, and is a super-cool place to sup.
1 SUPER-COOL Daryl McFadyen held his nerve to score the decisive spot-kick as Ants won through 4-2 on penalties after a West of Scotland Cup stalemate.