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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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College students help develop waste-measuring device at Hanford
A partnership between Washington River Protection Solutions (WRPS) and Washington State University has resulted in the development of a device to measure radioactive and chemical tank waste at the Hanford Site. WRPS is the contractor at Hanford for the Department of Energy’s Office of Environmental Management.
S. J. Raffety, J. T. Mihalczo
Nuclear Science and Engineering | Volume 48 | Number 4 | August 1972 | Pages 433-443
Technical Paper | doi.org/10.13182/NSE72-A22511
Articles are hosted by Taylor and Francis Online.
A series of clean critical experiments has been performed with homogeneous mixtures of finely divided U(2)F4 or U(3)F4 dispersed in dispersed in paraffin with H/235U atomic ratios varying from 133 to 972. The assemblies were constructed in rectangular geometry, and minimum critical masses and volumes in cylindrical and spherical geometries were obtained from buckling conversions. The minimum critical spherical volumes of a U(2)F4-paraffin mixture when unreflected and when reflected with an effectively infinite solid hydrogenous material are 199 and 138 liters, respectively, and the minimum critical 235U masses are 7.5 and 5.4 kg, respectively. The experiments with the U(3)F4-paraffin mixtures were not extensive enough to determine experimentally the values at optimum moderation but transport theory calculations indicate that the unreflected and reflected minimum critical volumes are about 93 and 57 liters, respectively, and that the minimum critical masses are about 4.1 and 2.7 kg of 235U, respectively. Measurements of the 238U-to-235U fission ratio indicated that in some assemblies as much as 6.5% of the fissions occurred in 238U. Prompt-neutron decay constants, α = βeff/1 were measured in reflected and unreflected delayed-critical assemblies of several fuel mixtures by the pulsed-neutron technique; the infinite-medium neutron multiplication factor, k∞, for the various fuel mixtures was inferred from height perturbation measurements.Transport theory calculations of k∞ and feff have been made using various cross-section sets.