Dunning, John Ray (1907-1975) American physicist who first measured the energy released in nuclear fission (1939), and the next year demonstrated the fission of uranium-235. He later helped to develop the gas-diffusion method of isotope separation used in making the first two atomic bombs. Related category • PHYSICISTS Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |