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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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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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.
S. Tassan
Nuclear Science and Engineering | Volume 26 | Number 2 | October 1966 | Pages 271-276
Technical Paper | doi.org/10.13182/NSE66-A28169
Articles are hosted by Taylor and Francis Online.
Thermal spectrum measurements in 1% enriched uranium, 0.387-in. diam rod lattices, light water moderated, have been performed by the lutetium activation method in order to test the usefulness of this technique in not-well-thermalized lattices. Dysprosium-164 and 175Lu were used as reference thermal-neutron detectors. The experimental results are presented as the average values of the normalized (lattice/Maxwellian) activation ratios of 176Lu/Dy and 176Lu/ 175Lu with the pertinent cadmium-ratios, in the fuel and in the moderator over the H2O/U range from 1:1 to 4:1. The agreement with the results of a calculation performed using the THERMOS code is satisfactory. It is concluded that the 176Lu/Dy set appears to be adequate for the thermal spectrum analysis of light-water-moderated lattices, while the 175Lu/Dy set can provide rather accurate integral data for the epithermal component of the neutron spectrum.