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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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NEA issues call to action in report on nuclear cost reductions
A new report from the Paris-based OECD Nuclear Energy Agency declares that nuclear power is needed for countries to meet their Paris Agreement decarbonization and energy security policy goals, but that governmental support for a rapid reduction in the cost of new nuclear capacity through the creation of certain policy frameworks is likely necessary.
L. J. Esch, M. L. Yeater, W. E. Moore, K. W. Seemann
Nuclear Science and Engineering | Volume 46 | Number 2 | November 1971 | Pages 223-235
Technical Paper | dx.doi.org/10.13182/NSE71-A22356
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The double differential neutron scattering cross section for water has been measured at temperatures of 27, 170, and 270°C, The RPI linear electron accelerator provided the pulsed neutron source for a time-of-flight analysis of neutron energy. By phasing the LINAC with a high speed chopper, incident neutron energies ranging from 0.04 to 0.632 eV were selected. Energy distributions of scattered neutrons were obtained at scattering angles of 10, 14, 25, 40, 60, 90, 120, and 150 deg. The relatively wide range of incident energies with good resolution made it possible to observe clearly the molecular energy levels. The structure was seen to broaden considerably in going from 27 to 170°C but was little changed by the further temperature increase. A model has been developed in which the water scattering system is considered as consisting of aggregates of molecules. These clusters have temperature-dependent sizes, and diffuse according to a temperature-dependent diffusion constant. The energy levels of the molecules bound in the cluster are represented by a multi-Gaussian frequency distribution which varies with temperature. The internal vibrations of the individual water molecules are represented by delta functions. A new approach has been taken in comparing this and other models with the data, involving the application of recent improvements in methods of treating resolution and multiple scattering: a Monte Carlo technique has been used to impose these conditions on the models. These comparisons, and comparisons with integral data, indicate that the new model should have advantages for reactor calculations.