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Young Members Group
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.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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DOE-EM awards $37.5M to Vanderbilt University for nuclear cleanup support
The Department of Energy’s Office of Environmental Management announced on January 16 that it has awarded a noncompetitive financial assistance agreement worth $37.5 million to Vanderbilt University in Nashville, Tenn., to aid the department’s mission of cleaning up legacy nuclear waste.
J. J. Rush, G. J. Safford, T. I. Taylor, W. W. Havens, Jr.
Nuclear Science and Engineering | Volume 14 | Number 4 | December 1962 | Pages 339-345
Technical Paper | doi.org/10.13182/NSE62-A26240
Articles are hosted by Taylor and Francis Online.
Recent neutron cross-section measurements have shown that certain ammonium salts and methyl substituted compounds may be useful as moderators for cold neutron sources. In the present experiments slow-neutron total cross sections for polycrystalline NH4PF6, (NH4)2S2O8, and (NH4)2CrO4 have been measured at 80°K and 296°K as a function of neutron wavelength. In addition cross sections have been measured at 23°C for NH4SO3F and CH3C≡CCH3. Cross sections vs. temperature for NH4PF6 and (NH4)2S2O8 were also obtained at λn = 8 A (0.0015 ev) from 80°K to room temperature. The long-wavelength slopes in b/A of the scattering cross sections per hydrogen atom at 23°C are: NH4PF6, 12.7; (NH4)2S2O8, 9.6; NH4SO3F, 10.0; (NH4)2CrO4, 5.5; CH3C≡CCH3, 12.4. The slope for NH4PF6 approaches that for free NH3 gas indicating a rotational barrier of ∼0.2 kcal/mole for the ammonium ion. The high slope for CH3C≡CCH3 indicates a low barrier to rotation of the methyl groups in this compound. The lower slopes for (NH4)2S2O8 and NH4SO3F show that the ammonium ions in these compounds have higher barriers of the order of O.7 to 1 kcal/mole. Slopes measured at 80°K are: NH4PF6, 2.5 b/A-H; (NH4)2S2O8, 1.0 b/A-H; (NH4)2CrO4, 0.0 b/A-H. In addition the cross section vs. temperature curve for NH4PF6 indicates no abrupt change in rotational barrier down to 80°K. These low-temperature results show the presence of significant rotational freedom in NH4PF6 even at 80°K. The presence of rotational states at low temperature for exchange of energy with neutrons, together with the comparatively low absorption cross sections, make ammonium salts such as NH4PF6 (N15 enriched) and methyl substituted compounds like CH3C≡CCH3 of interest as moderators for cold neutron sources.
