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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
R. C. Lloyd, E. D. Clayton
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 726-735
Technical Paper | doi.org/10.13182/NSE77-A15213
Articles are hosted by Taylor and Francis Online.
Knowledge of the effects of neutron absorbers on the criticality of uranium-plutonium systems is necessary to better establish criticality safety programs. These data are needed in setting criticality safety specifications for storage, processing, and shipping of fissile materials where it is desired to handle quantities with safety and efficiency. These data are also needed for validating calculational techniques and cross-section sets. Aqueous solutions of the nitrates of uranium and plutonium were used in these experiments to determine the effect of neutron absorbers on criticality. In some experiments, UO2 and PuO2 rods were latticed in the solutions to which various amounts of gadolinium and a gadolinium-boron mixture were added. Critical dimensions were measured of homogeneous mixtures of the solutions with varying amounts of gadolinium and gadolinium-boron added. The effect of boron-glass Raschig rings on the criticality of the solutions was also determined. Plutonium comprised 30 wt% of the uranium-plutonium component of the solution.