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.
Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
2021 ANS Virtual Annual Meeting
June 14–16, 2021
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
Latest Journal Issues
Nuclear Science and Engineering
Fusion Science and Technology
Dickman sheds light on Fukushima wastewater issue during CNBC interview
Paul Dickman, former senior official with the Nuclear Regulatory Commission who served as the study director for the ANS Special Committee on the Fukushima Daiichi accident, discussed Japan’s plans to dispose of Fukushima wastewater during an appearance on CNBC’s Street Signs Asia with hosts Amanda Drury and Tanvir Gill on April 16.
Appearing on the show as an ANS spokesman, Dickman assured the hosts that there will be no negative environmental impact from releasing the advanced liquid waste processing system (ALPS)-treated water into the Pacific Ocean. “The Japanese government has done an extraordinary effort to mitigate any harm that would be from the release of this water,” Dickman said. “Frankly, they’ve diluted it to such an extent that it would hardly be detectable above background (radiation).”
Robert B. Hayes
Nuclear Technology | Volume 197 | Number 2 | February 2017 | Pages 209-218
Technical Paper | dx.doi.org/10.13182/NT16-98
Articles are hosted by Taylor and Francis Online.
Some quality considerations for use in isotopic dating are presented to identify and correct heretofore unidentified overestimate scenarios. These include to a lesser degree the statistical interpretation issues with linear-least-squares fitting results but more importantly the isotope effect in the individual components of the isochron coefficient ratios. By taking into consideration the isotope effect (differential mass diffusion rates) when measuring isotopic ratios from very old samples, the distribution dependency in the coefficient ratios will cause a bias if isotopic diffusion rates are not identical throughout a sample. The isotope effect is that isotopes having a smaller atomic mass will diffuse faster throughout a medium than will their heavier counterparts causing concentration gradients of their ratios even when there are no contributions from radioactive decay. The application to Rb/Sr dating is evaluated and shown to result in expected age overestimates when isotopic ratios are employed to linearize the isochron. A suggested method to test for this effect is argued to require rigorous statistical analysis. An associated optimal sampling technique would involve using single-grain etching. It is also shown that the only method to fully eliminate the isotope effect is to not use isotopic ratios at all in radioisotopic dating as the physics do not require the use of isotopic ratios for geochronological dating. However, without the ratios, the data are inherently noisy.