Posted By: vitas (vitas) on 'CZscience' Title: Re: Obnovitelne zdroje, cista energie Date: Thu Apr 20 13:26:24 2006 Ahoj, > > Nevyrabeji se jaderne hlavice z plutonia, ktere je "odpadem" z elektraren? > > Hm, jak tak koukam do wikipedie tak je pravda ze se da pouzit i U235 > > http://en.wikipedia.org/wiki/Nuclear_weapon_design , otazka z ceho jsou > > vyrobeny ty kterych maji USA a Rusko 3x ... spoustu. > > Co si pamatuju, co bylo ve zpravach, tak pro elektrarny musi byt uran > obohacen > o izotop 235 neco kolem 5% a pro jaderne zbrane to bylo o dost vice, ted > nevim presne kolik (30%?). Cituji z vyse uvedeneho odkazu: Uranium which is more than 20% U-235 is called highly enriched uranium (HEU), and weapons grade uranium is at least 93.5% U-235. U-235 has a spontaneous fission rate of 0.16 fissions/s-kg. which is low enough to make super critical assembly relatively easy. The critical mass for an unreflected sphere of U-235 is about 50 kg, which is a sphere with a diameter of 17 cm. The critical size can be reduced to about 15 kg with the use of a neutron reflector surrounding the sphere. Nebo-li: ten uran z hlavic by se asi musel ochuzovat nez by se dal do elektrarny, coz ale urcite zdaleka neni tak tezke jako ho na takovouto hodnotu obohatit. vitas @;;