Media Contributed by Rick
Obama meets Rama X, 2012 President Barack Obama, with Secretary of State Hillary Rodham Clinton and Ambassador Kristie Kenney, left, meet with King Bhumibol Adulyadej of the Kingdom of Thailand, at Siriraj Hospital in Bangkok, Thailand, Nov. 18, 2012.
Chicago Pile-1 The first nuclear reactor was erected in 1942 in the West Stands section of Stagg Field at the University of Chicago. On December 2, 1942 a group of scientists achieved the first self-sustaining chain reaction and thereby initiated the controlled release of nuclear energy. The reactor consisted of uranium and uranium oxide lumps spaced in a cubic lattice embedded in graphite. In 1943 it was dismantled and reassembled at the Palos Park unit of the Argonne National Laboratory.
A nuclear fission chain reaction
- An uranium-235 atom absorbs a neutron, and fissions into two (fission fragments), releasing three new neutrons and a large amount of binding energy.
- One of those neutrons is absorbed by an atom of uranium-238, and does not continue the reaction. Another neutron leaves the system without being absorbed. However, one neutron does collide with an atom of uranium-235, which then fissions and releases two neutrons and more binding energy.
Title page of the assembly language code that produced Altair BASIC Developed by Allen, Gates, and Monte Davidoff, with two early Microsoft business cards showing Gates as president and Allen as vice president
