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Weapons grade plutonium (with greater than 90% 239 Pu) is used to make nuclear weapons and has many advantages over other fissile material for that purpose. Lower proportions of 239 Pu would make a reliable weapon design difficult or impossible; this is due to the spontaneous fission (and thus neutron production) of the undesirable 240 Pu.
Specific activity (symbol a) is the activity per unit mass of a radionuclide and is a physical property of that radionuclide. [1] [2] ... 239 Pu: 24.11 × 10 3 years ...
Weapons-grade plutonium is defined as being predominantly Pu-239, typically about 93% Pu-239. [24] Pu-240 is produced when Pu-239 absorbs an additional neutron and fails to fission. Pu-240 and Pu-239 are not separated by reprocessing. Pu-240 has a high rate of spontaneous fission, which can cause a nuclear weapon to pre-detonate. This makes ...
The most stable are 244 Pu with a half-life of 80.8 million years; 242 Pu with a half-life of 373,300 years; and 239 Pu with a half-life of 24,110 years; and 240 Pu with a half-life of 6,560 years. This element also has eight meta states ; all have half-lives of less than one second.
The "reactor-grade" plutonium produced by a regular LWR burnup cycle typically contains less than 60% Pu-239, with up to 30% parasitic Pu-240/Pu-242, and 10–15% fissile Pu-241. [127] It is unknown if a device using plutonium obtained from reprocessed civil nuclear waste can be detonated, however such a device could hypothetically fizzle and ...
In a fission nuclear reactor, uranium-238 can be used to generate plutonium-239, which itself can be used in a nuclear weapon or as a nuclear-reactor fuel supply. In a typical nuclear reactor, up to one-third of the generated power comes from the fission of 239 Pu, which is not supplied as a fuel to the reactor, but rather, produced from 238 U. [5] A certain amount of production of 239
If compared with MOX fuel, the activity around one million years in the cycles with thorium will be higher due to the presence of the not fully decayed 233 U. For natural uranium fuel, fissile component starts at 0.7% 235 U concentration in natural uranium. At discharge, total fissile component is still 0.5% (0.2% 235 U, 0.3% fissile 239 Pu ...
One of four example estimates of the plutonium (Pu-239) plume from the 1957 fire at the Rocky Flats nuclear weapons plant. The Rocky Flats Plant, a former United States nuclear weapons production facility located about 15 miles (24 km) northwest of Denver, caused radioactive (primarily plutonium, americium, and uranium) contamination within and outside its boundaries. [1]