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
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
Yeon Soo Kim
Nuclear Technology | Volume 130 | Number 1 | April 2000 | Pages 9-17
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT00-A3073
Articles are hosted by Taylor and Francis Online.
The literature dealing with fission gas release from UO2+x is reviewed. A simplified semiempirical model predicting fission gas release from UO2+x fuel to the fuel rod plenum as a function of stoichiometry excess x is developed to apply to the fuel of a defective light water reactor fuel rod in operation. An effective diffusion coefficient including a parabolic dependence of x is obtained based on existing data in the literature. The new diffusion coefficient is a composite expression of intrinsic, fission-enhanced, and nonstoichiometry-induced diffusion. The effective diffusion coefficient is incorporated into the Booth model to assess the time-dependent fractional fission gas release. The new model predictions are compared with existing data.
