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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
J. Nilsson and R. Sandlin
Nuclear Science and Engineering | Volume 23 | Number 3 | November 1965 | Pages 224-233
Technical Paper | doi.org/10.13182/NSE65-A19555
Articles are hosted by Taylor and Francis Online.
An investigation has been carried out concerning the transmission of thermal and fast neutrons in air-filled annular ducts. A calculational model to predict the air-gap flux is developed and fitted to the results from foil-activation experiments in a Fe-D2 O configuration, the duct length being about half a meter and the annular air gaps varying from 0.5 to 2.0 cm. It is based upon the condition that the flux is theoretically and experimentally divided into uncollided and collided components for both thermal and fast neutrons. The model may be applied to most of the straight annular ducts that occur in reactor shielding, but it is especially designed for the problems met with in short ducts.
