SSS 2008-08-08(在线收听) |
This is Scientific American’s 60-Second Science. I’m Steve Mirsky. Got a minute? Ever been woken up by the sound of the refrigerator compressor kicking on? Well, such clumsy heat exchange units featuring long metal coils may be on their way out. Because Penn State scientists are investigating the possibility of solid-state refrigerators that take advantage of electric fields to exchange heat.The researchers work with what are called ferroelectric polymers. When you apply an electric field to these substances, their internal structure goes from random to highly organized. And that makes the material colder. Turn off the electricity and the stuff sucks heat back in. In the August 8th issue of the journal Science, the researchers report an electrically induced temperature change of over 22 degrees Fahrenheit. Throw a heat exchanger into the mix and repeatedly zapping the polymers with electricity could make it possible to heat or cool a space over a wide range of temperatures. Before you get a solid-state fridge, though, look for electronics applications. The polymers could cool circuit boards, making it possible to jam more electronics closer together, leading to smaller devices. Thanks for the minute, for the Scientific American’s 60-Seconds Science. I’m Steve Mirsky. |
原文地址:http://www.tingroom.com/lesson/sasss/2008/8/98863.html |