Lieutenant-General Avraami Pavlovich Zavenyagin (1 May 1901, Nodal - 31 December 1956; his first name is also sometimes given as Avram or Abraham) was a leading figure in the Soviet nuclear projects of the 1940s and 1950s. A protege of Lavrenti Beria's, Zavenyagin survived the purge after the death of Joseph Stalin

Joseph Stalin

Joseph Vissarionovich Stalin was the Premier of the Soviet Union from 6 May 1941 to 5 March 1953. He was among the Bolshevik revolutionaries who brought about the October Revolution and had held the position of first General Secretary of the Communist Party of the Soviet Union's Central Committee...

 because of a long friendship with Nikita Khrushchev

Nikita Khrushchev

Nikita Sergeyevich Khrushchev led the Soviet Union during part of the Cold War. He served as First Secretary of the Communist Party of the Soviet Union from 1953 to 1964, and as Chairman of the Council of Ministers, or Premier, from 1958 to 1964...

which dated back to the 1920s. He died of a heart attack.