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Nuclear Energy Strategy announced at CNA2026
At the Canadian Nuclear Association Conference (CNA2026) in Ottawa, Ontario, on April 29, Minister of Energy and Natural Resources Tim Hodgson announced that Natural Resources Canada (NRCan) is developing a new Nuclear Energy Strategy for the country. The strategy, which is slated to be released by the end of this year, will be based on four objectives: 1) enabling new nuclear builds across Canada, 2) being a global supplier and exporter of nuclear technology and services, 3) expanding uranium production and nuclear fuel opportunities, and 4) developing new Canadian nuclear innovations, including in both fission and fusion technologies.
John T. Mihalczo
Nuclear Science and Engineering | Volume 20 | Number 1 | September 1964 | Pages 60-65
Technical Paper | doi.org/10.13182/NSE20-60
Articles are hosted by Taylor and Francis Online.
Prompt-neutron lifetimes have been determined for unreflected and unmoderated critical assemblies of enriched-uranium metal (93.15% U235) in cylindrical geometry. Five solid cylinders ranging in diameter from 7 to 15 in. and three cylindrical annuli having outside diameters as large as 15 in. were assembled to delayed critical and their prompt-neutron decay constants measured by the Rossi-α technique. The prompt-neutron lifetimes were determined from the measured decay constants and effective delayed-neutron fractions obtained by Sn multigroup transport-theory calculations, which predicted the multiplication constants of all assemblies to within 1/2%. For the solid cylinders the lifetime value is 6.25 ± 0.04 nsec, which, within the limits of experimental errors, is independent of the dimensions of the cylinders and agrees with the lifetime of 6.2 ± 0.1 nsec obtained from earlier prompt-neutron decay-constant measurements with a uranium sphere (Godiva I). For the cylindrical annuli the lifetime varied from 7.0 to 8.0 nsec. The increase in the lifetime value over that of the solid cylinders is due to the time required for neutrons to cross the center void.
