subcritical
61Reaction–diffusion system — Reaction–diffusion systems are mathematical models which explain how the concentration of one or more substances distributed in space changes under the influence of two processes: local chemical reactions in which the substances are transformed… …
62Demon core — The Demon core was the nickname given to a 6.2 kilogram (14 lb) subcritical mass of plutonium that accidentally went briefly critical in two separate accidents at the Los Alamos laboratory in 1945 and 1946. Each incident resulted in the… …
63Shutdown (nuclear reactor) — In a nuclear reactor, shutdown refers to the state of the reactor when it is subcritical by at least a margin defined in the reactor s technical specifications. Further requirements for being shut down may include having the reactor control key… …
64nuclear reactor — Physics. reactor (def. 4). Also called nuclear pile. [1940 45] * * * Device that can initiate and control a self sustaining series of nuclear fission reactions. Neutrons released in one fission reaction may strike other heavy nuclei, causing them …
65Delayed neutron — In nuclear engineering, a delayed neutron is a neutron emitted after a nuclear fission event by one of the fission products anytime from a few milliseconds to a few minutes later, similar to a prompt neutron decay which can occur within the same… …
66Startup neutron source — RBMK reactor control rod positions at the moment of the Chernobyl disaster; blue=startup neutron sources (12), yellow=shortened control rods from the reactor bottom (32), grey=pressure tubes (1661), green=control rods (167), red=automatic control …
67Nuclear power phase-out — A nuclear power plant at Grafenrheinfeld, Germany. Chancellor Angela Merkel s coalition announced on May 30, 2011, that Germany’s 17 nuclear power stations will be shut down by 2022, in a policy reversal following Japan s Fukushima Daiichi… …
68Curium — This article is about the chemical element. For the ancient city located in Cyprus, see Kourion. americium ← curium → berkelium …
69Comprehensive Nuclear-Test-Ban Treaty — (CTBT) Signed 10 September 1996 Location New York City Effective Not in force Condition 180 days after it is ratified by all 44 Annex 2 countries: Algeria, Argentina, Australia, Austria, Bangladesh, B …
70Nuclear fission — For the generation of electrical power by fission, see Nuclear power. Splitting the atom redirects here. For the EP, see Splitting the Atom. Nuclear physics Radioactive decay Nuclear fission Nuclear fusio …
