International recommendations provided by the International Commission on Radiation Protection (ICRP), as well as national regulations, set by the U.S. Nuclear Regulatory Commission (NRC), state that the exposure of skin to highly concentrated radioactive sources should be monitored at specified depths in skin and kept below specific dose equivalence levels....
Characteristic methods are widely known to be very accurate approaches to the
solution of numerical transport problems. These methods are most often used for
neutron transport applications (i.e. lattice physics calculations) where spatial cells
are of intermediate optical thickness (O(1) - O(100) mean free paths, depending on
the energy group)...
Fission product yields (FPYs) are used for a wide range of applications including nuclear fission theory, nuclear reactor design, reactor antineutrino anomaly, stellar nucleosynthesis, and nuclear forensics. These applications rely on FPYs that were last evaluated in 1993, which included measurements from all over the world up until 1993. In...
Mathematical modeling plays a pivotal role in understanding the mechanism of radiation-induced cellular effects, and also in quantifying the radiation risk to the cell. However, there are still compelling challenges facing the conventional modeling in radiobiology, such as lacking a generalized theory structure of quantifying target effect and non-target effect...
Characterization of uranium isotope compositions is of great interest in many nuclear sub-areas for safeguards purposes. Reprocessing facilities utilizing pyroprocessing raised an issue of uranium isotope monitoring due to the difficulty to apply traditional approaches under extreme environments. An rapid and remote method to characterize uranium isotope compositions for such...
Effective separation of lanthanides (Ln) from the minor actinides (MA) is a crucial technical challenge to closing the nuclear fuel cycle. This separation is a necessary prerequisite to transmute long-lived isotopes of Am and Cm, which will allow a reduction of the repository volume, thermal load, and radiological toxicity of...
There is renewed interest in the reliability and safety of nuclear power plants following the Fukushima Daiichi nuclear accident followed by 8.9 magnitude earthquake and Tsunami with the height of 15 m on March 11, 2011. Small Modular Reactors (SMRs) have been developed to improve safety systems by utilizing passive...
'Hot particle' skin dosimetry calculations are commonly performed using homogeneous dose-point kernels (DPK) in conjunction with scaling and backscatter models to account for non-homogeneous geometries. A new scaling model for determining the actual DPK for beta-particles transmitted by a high-Z source material has been developed. The model is based on...
For over 30 years, the Implicit Monte Carlo (IMC) method has been used to
solve challenging problems in thermal radiative transfer. These problems are typically optically thick and di ffusive, as a consequence of the high degree of "pseudo-scattering" introduced to model the absorption and reemission of photons from a...
Total electronic energies are calculated numerically for
free and singly-ionized He, Li, C, and Ne atoms using density
functional theory. Immersion energies are calculated for a single
C impurity atom embedded or absorbed into a charge-neutral system
composed of a free-electron gas with uniform positive background,
also called 'jellium'. Nonspherical...