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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.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
G. S. Gangwani, S. P. Tewari, L. S. Kothari
Nuclear Science and Engineering | Volume 57 | Number 1 | May 1975 | Pages 63-74
Technical Paper | doi.org/10.13182/NSE75-A40343
Articles are hosted by Taylor and Francis Online.
Calculations are reported for time-dependent, space-dependent, and steady-state neutron spectra in D2O ice assemblies of different dimensions and in the temperature range of 253 to 4 K. The scattering kernel used for these studies incorporates one- and two-phonon processes and is based on the Debye distribution function for the lattice vibrations of the D2O crystal. The multigroup Boltzmann diffusion equation was diagonalized to obtain transient and asymptotic spectra in assemblies at different temperatures with bucklings ranging from 0 to 0.15 cm-2. The calculated values of the effective decay constant are found to agree reasonably well with the experimental values reported by Salaita and Robeson at 253 K for waiting times of 160 to 320 μsec. The decay constants reported by Salaita and Robeson do not correspond to the asymptotic values, as claimed by the authors. The appropriate Boltzmann operator for the space-dependent problem was diagonalized to obtain its eigenvalues and eigenfunctions. By using these eigenfunctions, neutron spectra at different distances from the source plane were calculated in D2O ice at 253 K, and the diffusion lengths of neutrons were determined. Steady-state spectra in heavy ice assemblies at 77, 21, and 4 K were also investigated. The results for the effective neutron temperatures and the cold-neutron fractions agree well with the experimental results of Rush et al.