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NRC proposes changes to its rules on nuclear materials
In response to Executive Order 14300, “Ordering the Reform of the Nuclear Regulatory Commission,” the NRC is proposing sweeping changes to its rules governing the use of nuclear materials that are widely used in industry, medicine, and research. The changes would amend NRC regulations for the licensing of nuclear byproduct material, some source material, and some special nuclear material.
As published in the May 18 Federal Register, the NRC is seeking public comment on this proposed rule and draft interim guidance until July 2.
Tejbir Singh, Updesh Kaur, Shivali Tandon, Parjit S. Singh
Nuclear Science and Engineering | Volume 165 | Number 2 | June 2010 | Pages 240-244
Technical Note | doi.org/10.13182/NSE09-35TN
Articles are hosted by Taylor and Francis Online.
Photon interaction (ZPIeff) and photon energy absorption (ZPEAeff) effective atomic numbers have been computed for some amino acids, namely, alanine (C3H7NO2), arginine (C6H14N4O2), aspartic acid (C4H7NO4), glycine (C2H5NO2), isoleucine (C6H13NO2), serine (C3H7NO3), and valine (C5H11NO2) in the energy range of 1 keV to 20 MeV. It has been observed that the effective atomic numbers (photon interaction and photon energy absorption) for the selected amino acid differ only in the lower-energy region (5 to 100 keV) and the maximum deviation is observed at ˜30 keV. Further, the maximum values of the effective atomic numbers for photon interaction and photon energy absorption were observed to be at different energies. For the photon interaction effective atomic number, the maximum for the selected amino acids appears at ˜5 keV, whereas the photon energy absorption effective atomic number has its maximum for the selected amino acids at ˜15 keV. Among the selected amino acids, aspartic acid shows the maximum effective atomic number, whereas the least effective atomic numbers were observed for isoleucine.
