French scientists. Irene was a daughter of Pierre and Marie Curie. She were married in 1926. Both were assistants at the Radium Institute in Paris, of which Irene, succeeding her mother, was director in 1932. Together the Joliot-Curies continued the work of the Curies on radioactivity. For their artificial production of radioactive substances, in which they bombarded certain elements with alpha particles, they shared the 1935 Nobel Prize in Chemistry. In 1940 they collaborated on research on the chain reaction in nuclear fission. In 1946 they helped to organize the French atomic energy commission, and in the same year Frederic was appointed chairman of the commission. He was forced to resign in 1950, however, because of his Communist activities, and in 1951 Irene was also dropped from the commission because of her Communist affiliations. In 1947, Irene became a professor and the director of the radium laboratory at the Sorbonne. In 1956, Frederic was a member of the French Communist party's Central Committee, and in the same year he was appointed to the chair of nuclear physics at the Univ. of Paris.