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The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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Findings of the ANS Executive Order Expert Advisory Group
On May 23, President Donald Trump signed four Executive Orders (EOs) designed to “usher in a nuclear energy renaissance” by building on federal policies and programs and directing efficiencies in the licensing, siting, development, and deployment of advanced reactor technologies.
In order to evaluate the specific proposals contained in the EOs, a group of experts was convened from various sectors of the U.S. nuclear technology enterprise, under the auspices of the ANS External Affairs Committee, to compare the EOs against existing ANS board-approved Position Statements and to offer constructive input for subsequent implementation by the Trump administration.
The group’s findings and feedback, which were delivered by ANS CEO Craig Piercy to ANS President Lisa Marshall and the Board of Directors, are listed below, grouped by individual EO.
Mitsuo Manaka
Nuclear Technology | Volume 143 | Number 3 | September 2003 | Pages 335-346
Technical Paper | Radioactive Waste Management and Disposal | doi.org/10.13182/NT03-A3421
Articles are hosted by Taylor and Francis Online.
Immediately after the geological disposal of high-level radioactive waste, the oxygen initially existing in the repository is expected to strongly affect the redox condition of the near field. The oxygen dissolves in the groundwater, is transported by diffusion through it, and is consumed by the oxidation of pyrite as an impurity in bentonite. To assess the influence of the oxygen, this study was conducted to estimate the diffusion of dissolved oxygen (DO) and the rate of pyrite oxidation by DO in compacted purified and crude sodium bentonites (SBs) in more detail than the Manaka et al. study. The effective diffusion coefficient (De) of DO in the compacted purified SB was measured in low ionic strength solution (carbonate buffered solution with pH ~ 9) using the electrochemical method. The empirical equation between De value of DO and dry density (0.5 × 103-1.8 × 103 kg m-3) of purified SB was obtained as follows:DeDOKunipia-F = 8.2 ± 1.5 × 10-10× exp(-2.6 ± 0.2 ×10-3,where DeDOKunipia-F is the De of DO in compacted purified SB (Kunipia F) (m2 s-1) and is the dry density of the SB (kg m-3).On the other hand, the De value of DO in the compacted crude SB was estimated using the relationship between De values of tritiated water in compacted purified and crude SBs. The empirical equation between the De value of DO and dry density (0.5 × 103-1.8 × 103 kg m-3) of crude SB was derived as follows:DeDOKunigel-V1 = 2.04 × 10-9 exp(-2.6 × 10-3),where DeDOKunigel-V1 is the De of DO in compacted crude SB (Kunigel V1) (m2 s-1) and is the dry density of the SB (kg m-3).The rates of pyrite oxidation by DO were estimated from the experimental data in pyrite-purified SB systems using the obtained De values of DO. The relation between rate constant (k') of pyrite oxidation by DO and dry density () of the SB was derived as follows:k' = 3.9 ± 1.1 × 10-8 exp(-1.3 ± 0.3 × 10-3),where k' is the rate constant at pH ~ 9 in compacted purified SB of dry density ranging from 0.8 × 103 to 1.2 × 103 kg m-3.The rate constants of pyrite oxidation by DO in the compacted crude SB (0.8 × 103 to 1.2 × 103 kg m-3) were also calculated using the estimated De values of DO. In general, the values of rate constants in the crude SB are 1.5 times as large as that in the purified SB.
