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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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
ARPA-E announces $40 million to develop transmutation technologies for UNF
The Department of Energy’s Advanced Research Projects Agency–Energy (ARPA-E) announced $40 million in funding to develop cutting-edge technologies to enable the transmutation of used nuclear fuel into less-radioactive substances. According to ARPA-E, the new initiative addresses one of the agency’s core goals as outlined by Congress: to provide transformative solutions to improve the management, cleanup, and disposal of radioactive waste and spent nuclear fuel.
John T. Mihalczo
Nuclear Technology | Volume 175 | Number 2 | August 2011 | Pages 498-508
Technical Paper | Radiation Measurements and General Instrumentation | doi.org/10.13182/NT11-A12320
Articles are hosted by Taylor and Francis Online.
Prompt neutron decay at delayed criticality was measured by Oak Ridge National Laboratory for uranium-reflected highly enriched uranium (HEU) and Pu metal spheres (FLATTOP), for an unreflected Pu metal (4.5% 240Pu) sphere (JEZEBEL) at Los Alamos National Laboratory (LANL) and for an unreflected HEU metal sphere at Oak Ridge Critical Experiments Facility. The average prompt neutron decay constants from hundreds of Rossi- and randomly pulsed neutron measurements with 252Cf at delayed criticality are as follows: 3.8458 ± 0.0016 × 105 s-1 , 2.2139 ± 0.0022 × 105 s-1 , 6.3126 ± 0.0100 × 105 s-1 , and 1.1061 ± 0.0009 × 106 s-1 , respectively. These values agree with previous measurements by LANL for FLATTOP, JEZEBEL, and GODIVA I as follows: 3.82 ± 0.02 × 105 s-1 for a uranium core; 2.14 ± 0.05 × 105 s-1 and 2.29 × 105 s-1 (uncertainty not reported) for a plutonium core; 6.4 ± 0.1 × 105 s-1 , and 1.1 ± 0.1 × 106 s-1 , respectively, but have smaller uncertainties because of the larger number of measurements. For the FLATTOP and JEZEBEL assemblies, the measurements agree with calculations. Traditionally, the calculated decay constants for the bare uranium metal sphere GODIVA I and the Oak Ridge Uranium Metal Sphere were higher than experimental by [approximately]10%. Other energy-dependent quantities for the bare uranium sphere agree within 1%.