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Science

Israeli Scientists Freeze Water By Warming It 165

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."

Comment The problem isn't optics its processsing power (Score 2, Informative) 216

When it comes to taking video the limiting factor on video quality/resolution in a handheld device is almost always the processing power needed to encode said video in realtime, not the optics, which is why most phones with 5+MP cameras can save pictures at the full resolution of the CCD but videos are often limited to 640x480 at 25fps because that is all the processor can handle. For example my netbook with 1.3MP webcam takes far better quality videos than my sony ericsson phone with 5MP camera simply because it has the power to encode the video at a higher resolution in realtime. Of course if you have the storage space available to store the video uncompressed then its less of a problem but again we're talking a handheld device where storage space is by no means plentiful. And simply stuffing in a faster processor won't help because the power requirements mean a larger battery which means a larger device, and the whole point in these things is compact size.

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