الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
After the discovery by Hahn, Strassman, and Meitner that neutrons ,Induced fission in uranium, and that the number of neutrons relased in fission was greater than one, many scientists realized that it should be possible to build a chain-reacting system in which large amount of nuclear energy are released under controlled conditions. since that time, hundreds of nuclear reactors have been built through the world for research production 01 plutonium, and for power production. Nuclear chemistry must play an essential part in achieving safety and reliability in this most rapidly expanding source of power. Nuclear chemists are also responsible for much of the nuclear fuel cycle from uranium ore processing to ultimate disposal of radioactive reactor waste• The nuclear fuel cycle comprises the handling of all fissile and fertile materials necessary for nuclear power production and of the radioactive products formed in this process. The fuel cycle is suitably divided into a front end and a back and parts, where the nuclear power station is the dividing line. The front end comprises uranium exploration, mining, and refining. isotope enrichment, and fuel element fabrication, while the back end involves reprocessing and radioactive waste handling. Health and environmental aspects are important in all these steps, which are not considered as steps in tile nuclear fuel cycle. The composition of used reactor fuels varies as ,3 function of input composition {kinds and amount of fissile and fertile atoms}, the neutron spectrum and fluency and exposure time, and cooling time after removal from the reactor. increased burn-up increase the concentration of fission products and a larger amounts ’of higher actinides are formed. A high flux results in more high order reactions, while a long irradiation time produces relatively larger amounts of long-lived products. With increased cooling time the fraction of short-lived products is reduced.