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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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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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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How to talk about nuclear
In your career as a professional in the nuclear community, chances are you will, at some point, be asked (or volunteer) to talk to at least one layperson about the technology you know and love. You might even be asked to present to a whole group of nonnuclear folks, perhaps as a pitch to some company tangential to your company’s business. So, without further ado, let me give you some pointers on the best way to approach this important and surprisingly complicated task.
S. P. Tewari, L. S. Kothari
Nuclear Science and Engineering | Volume 39 | Number 2 | February 1970 | Pages 193-206
Technical Paper | doi.org/10.13182/NSE70-A21199
Articles are hosted by Taylor and Francis Online.
Calculations on the decay of a neutron pulse in H2O ice assemblies of various bucklings and at various temperatures in the range 273 to 21°K are reported. The scattering kernel is based on the Debye frequency distribution function of lattice vibrations, with a suitably chosen Debye temperature. Contributions from one- and two-phonon processes have been considered. The Boltzmann equation in the diffusion approximation has been solved both by an iterative procedure to obtain the fundamental mode of decay, and by a matrix diagonalization method. This latter method enables us to calculate neutron spectra at various times after the introduction of the neutron pulse. These time-dependent spectra have been compared with available experimental results with considerable success. By studying the time variation of the mean energy of the neutron distribution, we have calculated the slowing down relaxation times τth in ice at various temperatures and compared these with the measured values. We have also studied the heating up of a low-energy neutron pulse in ice assemblies at a few temperatures and find that, unlike the case of beryllium (Grover and Kothari) the heating up relaxation time τH comes out to be nearly the same as τth. The calculated values of diffusion coefficient D0, and diffusion cooling coefficient C at various temperatures have been compared with the experimental results. The agreement between the two sets of values is very good for D0, but not so good for C.
