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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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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.
Takashi Nakamura, Masahiko Fujii, Kazuo Shin
Nuclear Science and Engineering | Volume 83 | Number 4 | April 1983 | Pages 444-458
Technical Paper | doi.org/10.13182/NSE83-A18648
Articles are hosted by Taylor and Francis Online.
The energy spectra of neutrons emitted by thick targets of carbon, iron, copper, and lead at angles of 0, 15, 30, 45, 75, and 135 deg to the incident beam of 30- and 52-MeV protons were obtained by unfolding the pulse height distributions measured with an NE-213 scintillator. The angular distribution of neutrons above 3 or 4 MeV was obtained by integrating the measured spectra. The measured spectra were compared with a Monte Carlo calculation based on the Fermi free gas model of intranuclear cascades and evaporation. This comparison revealed that the calculated spectra are harder and stronger in the forward direction, but softer and weaker in the backward direction than are the experimental spectra. There is good agreement between the two at ∼75 deg. This experimental result showed that the calculational model is not adequate in the energy region below ∼100 MeV, where nuclear structure has a great influence on neutron production. The total neutron yield was obtained by estimating the neutron yield below a few million electron volts by fitting the spectra measured above that energy to the Maxwellian distribution and showed good agreement with other experimental results.