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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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.
S. R. Bierman, E. D. Clayton
Nuclear Science and Engineering | Volume 55 | Number 1 | September 1974 | Pages 58-66
Technical Paper | doi.org/10.13182/NSE74-A23966
Articles are hosted by Taylor and Francis Online.
There has been considerable interest in the use of fixed neutron absorbers (poisons) for criticality control since their use would permit safely handling larger quantities of nuclear materials with reduced probability of criticality. The effectiveness of such absorbers as neutron poisons depends on self-shielding effects which in turn are determined by the magnitude of the absorption cross sections and their variation with energy, the thickness of material, and the neutron-energy spectrum. For the fixed poisons to be considered as either a primary or secondary means of criticality control, their use must be based on a firm knowledge of these effects. To obtain experimental data in this area, the reactivity worth of two such materials, copper and copper containing 1 wt% cadmium, was recently measured in two different energy spectrums and at different thicknesses up to ≈2½ cm. The results of these measurements are presented in this paper and provide a set of clean, well-defined, poisoned critical assemblies that can be used to check calculational techniques and cross-section data., In the relatively thermalizwd neutron-energy spectrum, very little additional absorption was observed in the copper plate at thicknesses greater than ≈2½ cm or in the copper-cadmium plate at thicknesses greater than 1 cm. At thicknesses greater than these, self-shielding precluded any additional absorption, and the change in reactivity was due almost entirely to the additional void being introduced into the system by the poison plates., In the relatively fast neutron energy spectrum, neutron absorption was observed to continually increase with plate thickness for both sets of plates. However, in this spectrum the void effects, caused by the presence of the poison plates, had a greater reactivity worth, over the thickness range covered, than the neutron absorption., In either spectrum, the 1 wt% cadmium in the copper contributed significantly to the neutron absorption. Of course, the cadmium was found to be worth much more in the thermalized spectrum.