Search results
Results From The WOW.Com Content Network
Decay chain of 240 Pu. Plutonium-240 (240 Pu or Pu-240) is an isotope of plutonium formed when plutonium-239 captures a neutron.The detection of its spontaneous fission led to its discovery in 1944 at Los Alamos and had important consequences for the Manhattan Project.
240 Pu undergoes spontaneous fission at a small but significant rate (5.8 × 10 −6 %). [1] The presence of 240 Pu limits the plutonium's use in a nuclear bomb, because a neutron from spontaneous fission starts the chain reaction prematurely, causing an early release of energy that disperses the core before full implosion is reached. This ...
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
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 ...
The change in the definition for reactor grade, from describing plutonium with greater than 7% Pu-240 content prior to 1976, to reactor grade being defined as containing 19% or more Pu-240, coincides with the 1977 release of information about a 1962 "reactor grade nuclear test". The question of which definition or designation applies, that, of ...
After removal of fuel from reactor, decay will predominate for shorter-lived isotopes such as 238 Pu, 241 Pu, 242–244 Cm; but 245–248 Cm are all long-lived. Fertile material is a material that, although not fissile itself, can be converted into a fissile material by neutron absorption .
15. Plutonium. Cost: $4,400-$5,600 per gram. The devastating power of nuclear weapons, such as those used on Japan in World War II, probably makes plutonium more well-known than it otherwise might be.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us