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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
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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Nuclear Science and Engineering
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Nuclear Technology
Fusion Science and Technology
Latest News
Bipartisan Fusion Energy Act pushes for regulatory clarity
Sen. Alex Padilla (D., Calif.) introduced the Fusion Energy Act (S. 4151) last month with a bipartisan group of cosponsors—John Cornyn (R., Texas), Cory Booker (D., N.J.), Todd Young (R., Ind.), and Patty Murray (D., Wash.). The legislation would codify the Nuclear Regulatory Commission’s regulatory authority over commercial fusion energy systems to streamline the creation of clear federal regulations that will support the development of commercial fusion power plants—and would require a report within one year on a study of risk- and performance-based, design-specific licensing frameworks for “mass-manufactured fusion machines.
“Congress must do everything in its power to ensure continued U.S. leadership in developing commercial fusion energy facilities,” said Padilla as he introduced the bill. “The Fusion Energy Act would provide regulatory certainty for investors as the NRC develops and streamlines frameworks for such facilities.”
Benjamin A. Lindley, N. Zara Zainuddin, Paolo Ferroni, Andrew Hall, Fausto Franceschini, Geoffrey T. Parks
Nuclear Technology | Volume 185 | Number 2 | February 2014 | Pages 127-146
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT13-53
Articles are hosted by Taylor and Francis Online.
Multiple recycle of transuranic (TRU) isotopes in thermal reactors results in degradation of the plutonium (Pu) fissile quality with buildup of higher actinides (e.g., Am, Cm, Cf), some of which are thermal absorbers. These phenomena lead to increasing amounts of Pu feed being required to sustain criticality and accordingly larger TRU content in the multirecycled fuel inventory, ultimately resulting in a positive moderator temperature coefficient (MTC) and void reactivity coefficient. Because of the favorable impact fostered by use of thorium (Th) on these coefficients, the feasibility of Th-TRU multiple recycle in reduced-moderation pressurized water reactors (PWRs) and boiling water reactors (BWRs) has been investigated. In this paper, Part I of two companion papers, the analysis is limited to a single assembly, with full-core models presented in Part II. Spatial separation of TRU from bred uranium is found to greatly improve neutronic performance. A large reduction in moderation is necessary to allow full actinide recycle. This will pose thermal-hydraulic challenges, which are discussed in Part II. In addition, the harder neutron spectrum resulting from the reduced moderation also reduces the control rod worth, while there is a neutronic incentive to use increased mechanical shim to maintain a negative MTC. It may therefore be desirable to increase the number of rod cluster control assemblies. Superior burnup is achievable in a reduced-moderation BWR as a larger reduction in moderation is feasible, although the incineration rate is reduced relative to a PWR due to a higher conversion ratio.