It was a neutron (Neutron), which was discovered in 1932 by the English physicist James Chaddock (James Chadwick 1891-1974) as one of the nuclei of atoms are the key that enables scientists from which to exploit the potential energy in the nuclei of atoms components. Scientists have used neutrons to study the installation of an atom's nucleus, to its ability to penetrate the positively charged nucleus without any little resistance because they do not carry any electric charge. Italian world was made famous Enrico Fermi (Enrico Fermi 1901-1954) in 1934, throwing most of the periodic table elements with neutrons and managed to get a large number of radioactive isotopes because of this fusion neutrons Bonoah ejected elements. And when he came round to throwing the nucleus of uranium component Fermi noted that his radiation has dramatically increased to consider where it emitted particles and radiation of high intensity can not be explained by assuming that the uranium may be turned into one of his peers. And uranium radiation remained a puzzle to enable each of the German scientist Otto Hahn (Otto Hahn 1879-1968) and Austrian Swedish scientist not Mitner (Lise Meitner 1878-1968) Austrian and British world Otto Frisch (Otto Frisch 1904-1979) in 1939 to prove the uranium atom ejected may split into two atoms with neutrons ejected after two Dhirta krypton and barium was accompanied by the emergence of a large amount of energy in the form of radiation and particles off at high speeds.
It surprises good news for scientists who have focused their efforts on the study of this phenomenon is strange that they found that the fission of uranium atoms does not require high-energy neutron ejected but that fission may be thermal or slow neutrons and carrying capacity for half an electron volt, leaving them optimistic too much possibility of exploiting corn energy. The other discovery, which sparked the curiosity of scientists is the phenomenon of the emission of between two and three free neutrons as a result of throwing the uranium atom and one neutron. It has predicted the world the Hungarian American Leo Szilard (Leó Szilárd 1898-1964) in 1933, the possibility of a nuclear chain reaction (nuclear chain reaction) if there is sufficient quantity of uranium where sufficient neutron and one to start the process of nuclear reaction and then provide for neutrons resulting from the fission of the atom uranium to cause a row and growing fissions this process takes place in less than the blink of an eye produces a huge amount of energy in the form of a stunning explosion if not controlled, as is the case in nuclear bombs. But if the rate of reproduction of neutrons to control it is possible to determine the amount of fission and energy produced rate as in nuclear reactors.
But the joy of scientists this discovery did not last long it has been shown to them later to slow the neutrons do not cleave only one isotope of uranium, U-235, which constitutes less than one percent of natural uranium, while is the main isotope which is 238 more than nine and ninety percent and the latter does not cleaved only neutrons high speed capacity of more than 10 million electron volts. One oddity coincidences that scientists discovered in time a new element, a fissionable element plutonium-239, a synthetic element does not exist in nature was discovered in 1940 during the extrusion of uranium 238 with neutrons. Scientists have managed in less than two years to build reactors for the purpose of producing plutonium has been produced large amounts of it and the cost is negligible with the cost of production of uranium-235 was used in the manufacture of fissile atomic bombs.
One of the problems faced by scientists in the design of nuclear reactors is the strange way it interacts uranium 238 with neutrons is absorbed greedily neutrons ranging capacity between one and seven electron volts transformed it into plutonium-239 fissionable element while absorbs neutrons less than or greater than its capacity for energy this band splits not only with neutrons which increase capacity for ten million electron volts. In spite of the significant role played by the absorption of neutrons in the production of plutonium for the atomic bomb-making property, they in turn hinder significantly the chain reaction in nuclear reactors, a process where a large proportion of neutrons resulting from the fission of uranium 235 is located within the absorption range of uranium-238 is needed to overcome this problem slow the neutrons to the low speeds in the so-called thermal neutrons (thermal neutrons) in order to avoid hunted by uranium atoms 238 and through the use of some materials Alambtih Kjeravi and water, light and heavy, which have the ability to slow the neutrons without the absorbing.
When the fission of the atom after the ejection Balniotron they are often divided into two atoms is relatively combi total weigh less than the weight of fissile atom is launching a range of neutrons and beta particles (β - particles) and gamma rays (γ-rays). And it is fission of the atom process in the form of a powerful explosion because Nwati atoms Alnatjtin dividing carrying a positive charge, whereupon the strength disharmony between them pay atoms in opposite directions and speeds are very high and this has been the energy association converter (binding or potential energy) into kinetic energy (kinetic energy). Kinetic energy carried by the atoms resulting from the division of nearly 85% and pose while carrying particles and radiation energy remaining. For example, the energy generated by fission atom of uranium-235 amounting to 202 million electron volts of which 169 million electron volts in the form of kinetic energy carried by atoms Alnatjtin and five million electron volts as energy mobility in neutrons and 7 million electron volts as energy kinetics in beta and 13 million electron particles volt as energy gamma rays in the electromagnetic and 8 million electron volts as energy stored in the excited atoms resulting from division and in the form of stable isotopes is transformed into stable elements after the radiation energy. As it is clear that 90% of the energy generated by fission of the atom kinetic energy is converted entirely into heat energy when the collision of atoms and particles Natjat for fission atoms surrounding corn ordnance.
The atoms Alkhviqh resulting from fission of heavy atoms as well as the type and number of neutrons and energy generated depends on the type of item has shattered into sharp as well as on the neutron energy carried by splitting the atom. When fissionable uranium atom 235 more than the potential for the type of atoms produced and the number of neutrons first stakes are is the fission of the atom into two atoms of barium (141Ba barium) and krypton (92Kr krypton) and the production of three neutrons The second possibility is the fission of the atom into two atoms of cesium (144Cs Caesium) and rubidium (90Rb rubidium) and the production of two neutrons and two third possibility is the fission of the atom into two atoms of xenon (143Xe xenon) and strontium (90Sr strontium) and the production of three neutrons.
