Device converts radioactive energy directly into motion

摘要

A microscopic device that is said to convert the energy stored in radioactive material directly into motion has reportedly been built by researchers at Cornell University, Ithaca, N.Y. The prototype is made of a copper strip 1mm wide, 2cm long, and 60 microns thick. It is cantilevered by tiny rod above a thin film of nickel-63, a radioactive isotope. As the isotope decays, it emits beta particles, which are electrons. The emitted electrons collect on the copper strip, building a negative charge. The isotope film, having lost electrons, becomes positively charged. The attraction between positive and negative bends the rod down. When the rod gets close enough to the nickel film, a current flows, equalizing the charge. The rod springs up, and the process repeats.