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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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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.
Mitsuo Manaka, Manabu Kawasaki, Akira Honda
Nuclear Technology | Volume 130 | Number 2 | May 2000 | Pages 206-217
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT00-A3088
Articles are hosted by Taylor and Francis Online.
The redox condition of the near field is expected to affect the performance of engineered barrier systems. In particular, the oxygen initially existing in the pore spaces of compacted bentonites strongly affects the redox condition of the near field. To assess the influence of the oxygen, research was done to assess its transport parameters in the compacted bentonite and consumption process. To understand the diffusion of dissolved oxygen (DO) in compacted bentonite and to predict the effect of the DO, the measurements of the effective diffusion coefficient of DO in compacted sodium bentonite were made by electrochemistry. As a result, the following relationship between the dry density of compacted sodium bentonite and the effective diffusion coefficient of DO in compacted sodium bentonite was derived: De = 3.0 ± 0.5 × 10-9 exp(-3.7 ± 0.2 × 10-3), where De is the effective diffusion coefficient (m2 s-1) of DO in compacted sodium bentonite and is the dry density (kg m-3) of compacted sodium bentonite.The oxygen concentration in the bentonite is expected to be controlled by the oxidation of pyrite as an impurity in the bentonite. To investigate this idea, the rates of pyrite oxidation by DO in compacted sodium bentonite were estimated from the experimental data in pyrite-bentonite systems using the obtained effective diffusion coefficient of DO. The results show that the average of the rate constants of pyrite oxidation by DO in compacted sodium bentonite was 1.16 ± 0.35 × 10-8 m s-1, whereas the rate constant in a carbonate-buffered solution (pH = 9.24) was 1.46 ± 0.09 × 10-9 m s-1.
