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Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Mark S. Jarzemba, James Weldy, English Pearcy
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 275-281
Technical Paper | doi.org/10.13182/NSE131-275
Articles are hosted by Taylor and Francis Online.
Two subcritical assemblies (consisting of a subcritical reactor plus a neutron emitter such as 252Cf) designed for conducting neutron activation analyses in the field are described. The size of the assemblies has been minimized (compared to conventional, graphite-moderated assemblies) to allow for field portability. Although less powerful than using a research reactor as the source of neutrons, these assemblies will provide an adequate source of neutrons for detecting gold concentrations in rock or soil samples down to the limits of economic importance. Using a field-portable source of neutrons eliminates the need for shipping samples back to the reactor for analysis, which may be important for reasons of sample security and measurement turnaround time. The two subcritical assemblies are composed of natural uranium metal as the multiplying material and high-density polyethylene as the moderator, and they have keff approximately equal to 0.8 for the smaller assembly (~692-kg assembly mass) and 0.9 for the larger assembly (~3059-kg assembly mass). The larger assembly was found to be more desirable from a neutronics standpoint; however, it may be too massive to maintain field portability. It was found that the optimal location for the irradiation facility (a 4.0-cm-high, 2.0-cm-diam right cylinder) in the subcritical assemblies is the grid location as close to the neutron emitter location as possible. It was also found that the total, epithermal plus thermal (i.e., neutron energy <0.5 eV), and thermal (i.e., neutron energy <0.05 eV) volume-averaged neutron fluxes were as follows (assuming a neutron emitter source strength of 109 n/s): 1.72 × 108, 4.47 × 107, and 2.15 × 107 cm-2s-1 for the smaller assembly, and 3.43 × 108, 9.09 × 107, and 4.37 × 107 cm-2s-1 for the larger assembly. Although the purpose for which the assembly was designed was for conducting neutron activation analyses for gold, the assemblies should also work equally well for analyzing sample compositions of other elements at both the bulk and trace levels.