Nanotech

Nanogenerators May Spark Miniature Machines (Update) from PhysOrg.com

Researchers have developed a new technique for powering nanometer-scale devices without the need for bulky energy sources such as batteries. By converting mechanical energy from body movement, muscle stretching or water flow into electricity, these "nanogenerators" could make possible a new class of self-powered implantable medical devices, sensors and portable electronics.
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