ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Nuclear Technology | Volume 93 | Number 1 | January 1991 | Pages 53-64
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT91-A34518
Articles are hosted by Taylor and Francis Online.
A postulated loss-of-residual heat removal (RHR) event for a reactor coolant system (RCS) in a midloop condition is analyzed for the Palo Verde Nuclear Generating Station (PVNGS) using the RETRAN-2/MOD4 computer code. The PVNGS is a Combustion Engineering, two-loop, 3800-MW(thermal) pressurized water reactor (PWR). This analysis was prompted by the U.S. Nuclear Regulatory Commission generic letter 88-17, which requires PWR licensees to perform analyses of loss-of-RHR events for their facilities. Such analyses yield a detailed understanding of loss-of-RHR events and provide a basis for emergency procedures and recovery actions. Simulations of events following a loss of RHR are used to determine the time for RCS coolant to reach boiling, evaluate the potential for a rapid core uncovery due to pressurization of the reactor ves sel head with a corresponding liquid ejection from a cold-leg breach, and evaluate options for maintaining the RCS inventory above the core. Key features of the PVNGS midloop condition RETRAN model include isolating both steam generators from the RCS by nozzle dams, setting the initial RCS inventory at midloop, venting the RCS to containment by removing the pressurizer safety relief valves, defining a maintenance breach on one cold leg, and providing options to evaluate makeup water injection to a hot or cold leg by either pump or gravity feed. The RETRAN model provides a satisfactory method for dynamically evaluating loss-of-RHR events from a reduced RCS inventory condition, and for evaluating alternative recovery actions for PVNGS.