nuclear reactor: Quick Facts

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Temelín Nuclear Power Plant, South Bohemia, Czech Republic

Diagram showing the sequence of uranium nucleus fission after being struck by a neutron: the nucleus absorbs the neutron, deforms, splits into fragments, releases more neutrons and gamma rays, and emits beta particles as the fragments decay. Labels identify neutrons, protons, beta particles, and gamma rays, with accompanying explanatory text.

Diagram illustrating the moderated, controlled fission of uranium-235, showing uranium nuclei splitting after absorbing slow neutrons, releasing fast neutrons, and how moderators slow neutrons to sustain a controlled chain reaction.

nuclear power plant at Angra dos Reis, Brazil

Cherenkov radiation

Diagram of a nuclear reactor showing labeled parts including the control rod, reflector, moderator, nuclear fuel, biological shield, and coolant pipes for coolant in and out.

Cutaway diagram of a nuclear reactor core showing fuel assemblies inside a cylindrical reactor pressure vessel, with labeled components including control rod drive assembly, upper and lower grid plates, and a human figure for scale.

Diagram of a nuclear fuel assembly for a pressurized-water reactor, showing a vertical bundle of parallel fuel rods held by grid spacers, with control rods inserted among them, and labeled top and bottom nozzles.

Diagram showing three types of power cycles in nuclear power plants: a single-loop cycle with one closed water circuit from reactor to turbine, a two-loop cycle with separate primary and secondary loops connected by a steam generator, and a three-loop cycle adding a tertiary loop and heat exchanger for extra separation between the reactor and turbine systems.

Cutaway diagram of a pressurized-water nuclear reactor showing labeled parts including control rods, control rod drive mechanism, fuel assemblies, coolant inlets and outlets, thermal shields, and baffle plate.

A journey through the Chernobyl Exclusion Zone

How does a nuclear power plant generate electricity?

Hear about the April 1986 disaster at the Chernobyl nuclear power station and the catastrophe caused due to the escaping radiation

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Topics

control rod reactivity criticality critical core size BORAX ZOE critical concentration probabilistic risk assessment shielding storage pool turbine cooling system piston and cylinder injector electric motor battery electric generator pump magnetohydrodynamic power generator machine

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energy conversion: Fission reactors

Key People

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Frédéric Joliot-Curie

French chemist and physicist

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Irène Joliot-Curie

French chemist

Werner Karl Heisenberg sits at a desk in a suit with his hands folded, bookshelves in the background.

Werner Heisenberg

German physicist and philosopher

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Igor Vasilyevich Kurchatov

Soviet physicist

Hyman G. Rickover

Hyman G. Rickover

United States admiral

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Bruno Pontecorvo

Italian-born physicist

Men of the Royal Norfolk Regiment at Aldershot now undergoing a course of revolver shooting wear gas masks while at practice in order to got used to wearing the masks under all conditions. Two Tommies sighting the target in their gas masks. (World War I)

Do You Know Which African American Inventor Created Which Product?