Superconductivity a better environmental performance but could also improve public acceptance for expansion of the electric grid. Superconductivity Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic flux fields occurring in certain materials, called superconductors, when cooled below a characteristic critical temperature. It was discovered by Dutch physicist Heike Kamerlingh Onnes on April 8, 1911, in Leiden. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon. It is characterized by the Meissner effect, the complete ejection of magnetic field lines from the interior of the superconductor during its transitions into the superconducting state. The
Heike John Heike John Heike John (now Heike Walpot; born 19 June 1960) is a retired German swimmer and former astronaut candidate. She won a bronze medal at the 1977 European Aquatics Championships. She competed at the 1976 Summer Olympics in the 100 m and 200 m backstroke events but did not reach the finals. During her career she won five national titles in the 100 m (1977) and 200 m (1977, 1978) backstroke and 200 m medley (1977, 1978). She missed the 1980 Summer Olympics because of their boycott by West Germany. After her swimming career, she studied medicine at RWTH