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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Prepare for the 2025 Nuclear PE Exam with ANS guides
The next opportunity to earn professional engineer (PE) licensure in nuclear engineering is this fall, and now is the time to sign up and begin studying with the help of materials like the online module program offered by the American Nuclear Society.
Donald C. Coonfield, Grover Tuck, Harold E. Clark, Bruce B. Ernst
Nuclear Science and Engineering | Volume 39 | Number 3 | March 1970 | Pages 320-328
Technical Paper | doi.org/10.13182/NSE70-A19993
Articles are hosted by Taylor and Francis Online.
Critical masses have been determined by experiment and by calculation for enriched-uranium-metal spherical shells moderated internally with a sphere of mild steel of radius 8.01 cm. The shells were reflected with various thicknesses of mild steel followed by an effectively infinite amount of oil. The points representing critical mass as a function of the thickness of the steel reflector are not related by a smooth curve. The irregularity appears to be most severe for a 3-cm-thick steel reflector and is due to the resonance in the neutron elastic-scattering cross section of iron.
