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Atlanta, GA|Atlanta Marriott Marquis
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Nuclear energy for maritime shipping and coastal applications
The Boston-based Deon Policy Institute has published a white paper that examines the applications of nuclear energy in the maritime sector—specifically, floating nuclear power plants and nuclear propulsion for commercial vessels. Topics covered include available technologies, preliminary cost estimates, and a status update on the regulatory framework.
Unique opportunity: The paper points out that nuclear energy has the potential to benefit the shipping industry with high energy efficiency, lower operating costs, and zero carbon emissions. The report has a special focus on Greece, a nation that controls about 20 percent of the global commercial fleet and thus has an opportunity to take a leading role in the transition to nuclear-powered shipping.
J. T. Mihalczo
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 393-414
Technical Paper | doi.org/10.13182/NSE74-5
Articles are hosted by Taylor and Francis Online.
Cross-correlation measurements between the pulses from an ionization counter containing a 252Cf neutron source, which provided the initiators of fission chains in a neutron-multiplying assembly, and the pulses from a detector observing the particles from the fission chains leaking from the assembly were performed for unmoderated and polyethylene-moderated uranium (∼93 wt% 235U)-metal cylindrical assemblies with uranium masses varying from 12 to 160 kg and with prompt-neu-tron decay constants varying from 3 × 103 to 108 sec-1. The applicability of this randomly pulsed neutron method with 252Cf as the neutron source for the determination of the prompt-neutron decay in plutonium was investigated in experiments with unmoderated plutonium-metal assemblies with masses varying from 2.2 to 16 kg and with spontaneous fission rates from 240Pu varying from 4.5 × 104 to 8.2 × 105 fiss/sec. These assemblies included spheres and parts of spheres of plutonium with 4.5 or 20.1 at.% 240Pu. The ratio of the correlated count rate in the randomly pulsed neutron method to that in a Rossi-α method is inversely proportional to the detector efficiency and was as large as 8000 for some assemblies where both measurements were made. Thus, the randomly pulsed neutron method allowed the determination of the prompt-neutron decay without the use of a complicated pulsed-neutron source where the Rossi-α method was not practical. In assemblies for which Rossi-α measurements were also made, the prompt-neutron decay constant agreed within the precision (<1%) of the measurements with those obtained in much less time by this technique. Since the prompt-neutron decay can also be determined for plutonium-metal assemblies with ∼20 at.% 240Pu, using a californium source as small as 3000 fiss/sec, this technique can be used for the subcriticality determination for both unreflected and unmoderated uranium (93.2)- or plutonium-metal assemblies.
