Деление И Цепной Распад Урана

Extreme States in a Nuclear Explosion

“…To acquire the requisite data about the physical properties and gas-dynamic features of substance behavior under the extreme conditions of a nuclear explosion, a start was made on a complex of experimental and theoretical research programs, which gave birth to a new science-the physics of high energy densities [5, 10,36,37,110,122] and the dynamic physics of high pressures (Chap. 3).…”

“…Khariton, et al even in 1939 substantiated the feasibility of a nuclear fission chain reaction in uranium and therefore the prospect of practical use of a radically new-nuclearenergy source, millions of times more powerful than traditional chemical reactions. A short time later, conditions [122] for the realization of a chain nuclear reaction of explosive type (previously discovered by academician N.N. Semenov for chemical reactions) attended with the liberation of an unprecedented amount of energy.…”

“…Although it is an excellent nuclear fuel by itself (in the "bare ball" configuration its critical mass, like that of plutonium, is close to 15 kg [4,5,15,106,115,122]), its production is associated with major technical difficulties, because natural thorium does not contain a highfissility isotope (similar to uranium-235 in natural uranium). Meanwhile, adequate studies have been made of the nuclear fuel cycle whereby uranium-233 is produced in the reproduction zone, which accommodates natural thorium-232.…”

“…The nuclear explosion itself, if this term is meant to imply the primary energy liberation, develops in a time no longer than several microseconds-initially in the chain reaction of uranium or plutonium fission and then (in the case of a thermonuclear explosive device) in a certain sequence of tritium-deuterium nuclear fusion reactions [9,58,107,114,122]. While on the subject of a nuclear explosion, implied most often is the outward appearance ( Fig.…”

“…Furthermore, plutonium possesses favorable mechanical properties: unlike hard and brittle uranium, it is easily compressible. From the standpoint of weapons design, this permits realizing an efficient method of reaching the critical mass-implosion [4,5,15,115,122] (the passage to the supercritical state for an invariable mass by increasing the density and lowering the effective surface). The use of this method permits making modern nuclear ammunition with very high performance characteristics.…”