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:
“Physical nature lies at our feet shackled with a hundred chains. What of the control of human nature? Do not point to the triumphs of psychiatry, social services or the war against crime. Domination of human nature can only mean the domination of every man by himself.”
—Johan Huizinga (1872–1945)
“For the first fourteen years for a rod they do whine,
For the next as a pearl in the world they do shine,
For the next trim beauty beginneth to swerve,
For the next matrons or drudges they serve,
For the next doth crave a staff for a stay,
For the next a bier to fetch them away.”
—Thomas Tusser (c. 1520–1580)