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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Genn Saji, Roy A. Axford
Nuclear Science and Engineering | Volume 35 | Number 3 | March 1969 | Pages 319-331
Technical Paper | doi.org/10.13182/NSE69-A20010
Articles are hosted by Taylor and Francis Online.
A new theoretical formalism of the space-time kinetics is developed for heterogeneous reactor models. The basic time-dependent diffusion equation, which contains terms representing localized absorption and fast-neutron production by fuel rods, has been analytically transformed into a convolution integral form. This enables computation of space- and time-dependent flux for heterogeneous reactors by considering the sizes and spacings of the fuel rods, their geometrical locations, and the nuclear properties of the material used. Although the basic idea and mathematical formalism developed in this paper can be applied for various other space-time kinetics problems, the final calculation is performed for the forced oscillation problem. Two computer codes, HERMITS-1 and HERMITS-2, are developed. By using these codes, it is shown that contour maps of the static flux, phase angles, and amplitudes of neutron waves around the fuel rods can be calculated in an extremely short amount of machine time.