Fuel liquefaction release, fission products

In addition to destroying the UO2 matrix, fuel liquefaction accelerates the release of fission products from the fuel. However, minor alloying components or impurities can have large effects on such releases. For instance, tin, which is a 1% component of zircaloy, may act as a getter for tellurium resulting in significant holdup or retention of this fission product. Both fuel liquefaction and retention of tellurium in the presence of tin illustrate that chemical reactions are crucial to the understanding of severe accidents. 

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