X-10 Graphite Reactor Belgium. Financed through the Belgian uranium export tax, and built with the help of British experts, the 4 MW research reactor went critical for the first time on May 11, 1956. It is used for scientific purposes, such as neutron activation analysis, neutron physics experiments, calibration of nuclear measurement devices and the production of neutron transmutation doped silicon. X-10 Graphite Reactor The X-10 Graphite Reactor at Oak Ridge National Laboratory in Oak Ridge, Tennessee, formerly known as the Clinton Pile and X-10 Pile, was the world's second artificial nuclear reactor (after Enrico Fermi's Chicago Pile-1), and the first designed and
S1W reactor S1W reactor The S1W reactor was the first prototype naval reactor used by the United States Navy to prove that the technology could be used for electricity generation and propulsion on submarines. The S1W designation stands for The land-based nuclear reactor was built at the National Reactor Testing Station, later called Idaho National Engineering Laboratory near Arco, Idaho. The plant was the prototype for the USS "Nautilus" (SSN-571), the world's first nuclear-powered submarine. The specific location within the vast Idaho National Laboratory where the S1W prototype was located was the Naval Reactors Facility. Under the leadership of Admiral Hyman G.