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Hot contender ousts current champ

点击量:   时间:2019-03-15 07:20:00

By Melanie Cooper This is a classic article from New Scientist’s archive, republished as part of our 50th anniversary celebrations IN THE 1980s, “high-temperature superconductors” promised everything from magnetically levitating trains to resistance-free power lines and cheap MRI scanners. They have failed to deliver largely because they could not carry enough current. Now a material will not only conduct with zero resistance but has overtaken its rivals on the current it can carry. The material, magnesium diboride (MgB2),