Burnup is an important parameter in criticality safety evaluations of spent nuclear fuel in which burnup credit is taken into account. The Neodymium-148 method is widely used to evaluate the burnup of post irradiation examination (PIE) samples, and it is well known for its good accuracy. However, accuracy of the evaluated burnup values may be affected by the neutron capture reaction of 147 Nd and 148 Nd. Moreover, in the analysis of PIE data from a PWR, the calculation results of 148 Nd have more than a 1% deviation from the experiment. In this study, the contribution of neutron capture reactions of 147 Nd and 148 Nd to the amount of 148 Nd is discussed. The PIE data analyses using new evaluation of 147 Nd capture cross section show that the JENDL-3.2 cross section data is overestimated. The change in the amount of 148 Nd due to both reactions is less than 0.7% under normal reactor operation conditions. In particular, it is in the 0.1% range if burnup is approximately 30 GWd/t for a BWR and 40 GWd/t for a PWR.
Under an atmospheric pressure of hydrogen alkynes were successively hydrogenated to give alkanes via (Z)-alkenes with the metallic nickel catalyst, which was easily prepared by reaction of nickel bromide with zinc powder. Phosphines and diamines as catalyst modifiers were effective for the partial hydrogenation of alkynes.
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