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Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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Orlando, FL|Renaissance Orlando at SeaWorld
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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. R. Lee, P. B. Daitch
Nuclear Science and Engineering | Volume 28 | Number 2 | May 1967 | Pages 247-258
Technical Paper | doi.org/10.13182/NSE67-A17475
Articles are hosted by Taylor and Francis Online.
An eigenvalue-eigenfunction analysis of beryllium assemblies over a large buckling range has been performed in a discrete energy representation. Transverse harmonics and the treatment of the energy dependence of the transverse buckling are shown not to change the conclusions. The decay in small assemblies that do not have an asymptotic (discrete) eigenvalue is seen to be dominated by a highly excited region of the continuous eigenvalue spectrum. This is characterized as a pseudo-fundamental eigenvalue-eigenfunction and is seen to be responsible for the observation of experimental decay constants that are greater than the minimum interaction rate. The pseudo-fundamental eigenfunction is peaked at the Bragg energies and describes a trapping of neutrons at these energies for the intermediate times accessible to experiment. It is doubtful that the theoretical long-time buildup of near-zero-energy neutrons, seen as a peak at the lowest energy mesh point for the lowest “continuum” eigenfunction can be observed by experiment. Spatial effects are examined by comparing Marshak and zero-flux boundary-condition results. The Marshak boundary condition gives, for example, a 3% increase in the decay constant and a higher peak in the spectrum at the major Bragg energy for B2 = 0.0753 cm−2. A surface spectrum predicted by diffusion theory is seen to be in qualitative agreement with experiment. The P3 pseudofundamental eigenvalue is nearly identical to the diffusion theory result, lending support to the assumption that transport effects are not dominant for the times, energies, and assembly sizes considered here. Spectra at energies below the Bragg cutoff are very sensitive to the transport approximation used, but these energies are outside the experimental range and have a negligible effect on integral parameters, such as the decay constant. The major features of the theory are checked against experiment.