Production
Small amounts of fission products are naturally formed as the result of either spontaneous fission of natural uranium, which occurs at a low rate, or as a result of neutrons from radioactive decay or reactions with cosmic ray particles. The microscopic tracks left by these fission products in some natural minerals (mainly apatite and zircon) are used in fission track dating to provide the cooling ages of natural rocks. The technique has an effective dating range of 0.1 Ma to >1.0 Ga depending on the mineral used and the concentration on uranium in that mineral.
About 1.5 billion years ago in a uranium ore body in Africa, a natural nuclear fission reactor operated for a few hundred thousand years and produced approximately 5 tonnes of fission products. These fission products were important in providing proof that the natural reactor had occurred. Fission products are produced in nuclear weapon explosions, with the amount depending on the type of weapon. The largest source of fission products is from nuclear reactors. In current nuclear power reactors, about 3% of the uranium in the fuel is converted into fission products as a by-product of energy generation. Most of these fission products remain in the fuel unless there is fuel element failure or a nuclear accident, or the fuel is reprocessed.
Read more about this topic: Nuclear Fission Product
Famous quotes containing the word production:
“Just as modern mass production requires the standardization of commodities, so the social process requires standardization of man, and this standardization is called equality.”
—Erich Fromm (1900–1980)
“The heart of man ever finds a constant succession of passions, so that the destroying and pulling down of one proves generally to be nothing else but the production and the setting up of another.”
—François, Duc De La Rochefoucauld (1613–1680)
“Every production of an artist should be the expression of an adventure of his soul.”
—W. Somerset Maugham (1874–1965)