A control rod is a rod made of chemical elements capable of absorbing many neutrons without fissioning themselves. They are used in nuclear reactors to control the rate of fission of uranium and plutonium. Because these elements have different capture cross sections for neutrons of varying energies, the compositions of the control rods must be designed for the neutron spectrum of the reactor it is supposed to control. Light water reactors (BWR, PWR) and heavy water reactors (HWR) operate with "thermal" neutrons, whereas breeder reactors operate with "fast" neutrons.
Read more about Control Rod: Operation Principle, Materials Used, Safety
Famous quotes containing the words control and/or rod:
“There is one thing you and I as parents cannot do, not do we want to do if we really think about it, and that’s control our children’s will—that spirit that lets them be themselves apart from you and me. They are not ours to possess, control, manipulate, or even to make mind.”
—Barbara Coloroso (20th century)
“Yea, though I walk through the valley of the shadow of death, I will fear no evil: for thou art with me; thy rod and thy staff they comfort me.”
—Bible: Hebrew Psalms, 23:4.