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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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.
J. T. Mihalczo, T. E. Valentine
Nuclear Science and Engineering | Volume 121 | Number 2 | October 1995 | Pages 286-300
Technical Paper | doi.org/10.13182/NSE95-A28565
Articles are hosted by Taylor and Francis Online.
The 252Cf-source-driven noise analysis method has been used in measurements for subcritical configurations of fissile systems for a variety of applications, including a dynamic measurement that was the first step in applying this method to monitor nuclear fuel processing plants. Previous measurements have shown large changes in noise-measured parameters such as the coherences and ratio of spectral densities for small changes in the measured configuration of fissile material, for small changes in k, or for changes in other system variables. Direct calculation of the experimental observables by the Monte Carlo method allows the benchmarking of calculational methods and cross sections with a higher sensitivity to changes than calculations of the neutron multiplication factor itself. Measurements and sensitivity studies with the KENO-NR Monte Carlo neutron transport code showed that this measurement method has the potential to monitor many dynamic situations in processing plants such as in casting facilities, in a continuous dissolver, or in batch dissolvers either to be used as a signature to verify that various processes are occurring in a repeatable or bounded way or to obtain the neutron multiplication factor k. This verification of normal operation would be by comparing noise analysis signatures for the process with reference signatures. A Abnormal operation could be ascertained if the signature deviates by some specified amount from the reference signatures from normal operation. The deviations from normal could be specified by measurements or by Monte Carlo neutron transport theory methods directly calculating the measured parameters for the processing plant applications. Measurements with enriched uranyl nitrate solutions are presented as an example to demonstrate the high measured sensitivity of noise-measured parameters. To evaluate this high sensitivity, KENO-NR was used to investigate changes in the noise-measured parameters to variation in fissile system parameters using neutron transport calculations for three aqueous solutions, uranyl nitrate, uranyl fluoride, and plutonium nitrate, and also for an array of light water reactor spent fuel. This high sensitivity has also allowed this measurement method to be used to identify nuclear weapons and/or weapons components in shipping containers by comparing with reference signatures obtained from measurements or calculations and for nondestructive assay of special nuclear materials.