- Fertile material
Fertile material is a term used to describe
nuclideswhich generally themselves do not undergo induced fission (fissionable by thermal neutrons) but from which fissilematerial is generated by neutron absorption and subsequent nuclei conversions. Fertile materials that occur naturally which can be converted into a fissile materialby irradiation in a reactor include:
thorium-232which converts into uranium-233
uranium-234which converts into uranium-235
uranium-238which converts into plutonium-239Artificial isotopes formed in the reactor which can be converted into fissile materialby one neutron capture include:
plutonium-238which converts into plutonium-239
plutonium-240which converts into plutonium-241Some other actinidesneed more than one neutron capture before arriving at an isotope which is both fissile and long-lived enough to probably be able to capture another neutron and fission instead of decaying.
plutonium-242to americium-243 to curium-244 to curium-245
uranium-236to neptunium-237 to plutonium-238to plutonium-239
americium-241 to curium-242 to curium-243 (or, more likely, curium-242 decays to plutonium-238, which also requires one additional neutron to reach a fissile nuclide)Since these require a total of 3 or 4 thermal neutrons to eventually fission, and a thermal neutron fission generates only about 2 to 3 neutrons, these nuclides represent a net loss of neutrons. In a fast reactor, they may require fewer neutrons to achieve fission, as well as producing more neutrons when they do fission.
fast breederreactor, a reactor with little or no neutron moderatorand hence utilising fast neutrons, can be configured to produce more fissile material than it consumes, using fertile material in a blanket around the core, or contained in special fuel rods. Since plutonium-238, plutonium-240and plutonium-242are fertile, accumulation of these and other nonfissile isotopes is less of a problem than in thermal reactors, which cannot burn them efficiently.
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fertile material — noun An isotope (eg uranium 238) that can be readily transformed by the capture of a neutron into fissionable material (plutonium 239) • • • Main Entry: ↑fertile … Useful english dictionary
fertile material — n. material which can be converted into a fissile material by a neutron induced nuclear reaction, as uranium 238 or thorium 232 * * * … Universalium
fertile material — n. material which can be converted into a fissile material by a neutron induced nuclear reaction, as uranium 238 or thorium 232 … English World dictionary
Fertile material — См. Воспроизводящий материал Термины атомной энергетики. Концерн Росэнергоатом, 2010 … Термины атомной энергетики
Fertile material — Material that is not itself fissionable by thermal neutrons but can be converted to fissile material by irradiation. The two principal fertile materials are uranium 238 andthorium 232. U.S. Dept. of Energy, Energy Information Administration s … Energy terms
Fertile (disambiguation) — Fertile is the ability organisms, including people or animals, to produce healthy offspring.Fertile may also refer to: *Fertile material, nuclides which generally themselves do not undergo induced fission, but from which fissile material can be… … Wikipedia
fertile — adjective Etymology: Middle English, from Middle French & Latin; Middle French, from Latin fertilis, from ferre to carry, bear more at bear Date: 15th century 1. a. producing or bearing fruit in great quantities ; productive b. characterized by… … New Collegiate Dictionary
fertile — /ˈfɜtaɪl / (say fertuyl), Originally US / təl/ (say tuhl) adjective 1. bearing or capable of bearing vegetation, crops, etc., abundantly, as land or soil: a region fertile in wheat. 2. bearing offspring freely; prolific. 3. abundantly productive… … Australian English dictionary
fertile — adj. 1 a (of soil) producing abundant vegetation or crops. b fruitful. 2 a (of a seed, egg, etc.) capable of becoming a new individual. b (of animals and plants) able to conceive young or produce fruit. 3 (of the mind) inventive. 4 (of nuclear… … Useful english dictionary
fissile material — ▪ nuclear physics also called Fissionable Material, in nuclear physics, any species of atomic nucleus that can undergo the fission reaction. The principal fissile materials are uranium 235 (0.7 percent of naturally occurring uranium),… … Universalium