Getting the ice by heating the water.
As is known, the formation of ice usually occurs around a musorinki or dust. If not, then in a perfectly clean atmosphere even at normal pressure, water can remain liquid form down to -42° C. This so-called supercooled water, which is used in medicine, cryogenics, etc.
On the influence of the electric field at the freezing point of water has been known for over 150 years: in particular, in the electric field of the negative charge water freezes at lower temperatures. The most popular theory - is that water molecules are supposedly "change their orientation in the field, which complicates the crystallization of ice. Surprisingly, so far, this mechanism has not been fully explored. The problem is the absence of experimental data: the scientists could not manage to find the material through which you can skip the charge and who does not react with water.
Elegant experiment has come up with Igor Lubomirski with colleagues from the Weizmann Institute (Israel). The scientists used Pyroelectricity of lithium tantalate (LiTaO3), which changes its electric field when heated / cooled. In the absence of the charge drop of water on its surface freezes at -12,5° C. But if the surface is cooled, the lithium tantalate acquires a negative charge, and drops of water remain liquid to -18° C. If the surface is heated, then the positive charge of the water freezes at -7° C.
The scientific results published in the journal Science: David Ehre, Etay Lavert, Meir Lahav and Igor Lubomirsky, Science, 2010, DOI: 10.1126/science.1178085.
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On the influence of the electric field at the freezing point of water has been known for over 150 years: in particular, in the electric field of the negative charge water freezes at lower temperatures. The most popular theory - is that water molecules are supposedly "change their orientation in the field, which complicates the crystallization of ice. Surprisingly, so far, this mechanism has not been fully explored. The problem is the absence of experimental data: the scientists could not manage to find the material through which you can skip the charge and who does not react with water.Elegant experiment has come up with Igor Lubomirski with colleagues from the Weizmann Institute (Israel). The scientists used Pyroelectricity of lithium tantalate (LiTaO3), which changes its electric field when heated / cooled. In the absence of the charge drop of water on its surface freezes at -12,5° C. But if the surface is cooled, the lithium tantalate acquires a negative charge, and drops of water remain liquid to -18° C. If the surface is heated, then the positive charge of the water freezes at -7° C.
The scientific results published in the journal Science: David Ehre, Etay Lavert, Meir Lahav and Igor Lubomirsky, Science, 2010, DOI: 10.1126/science.1178085.
"Get Money for Clicks" - Fastest Growing Domain Parking Company in the World.
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