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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
J. R. L. de Ladonchamps, L. M. Grossman
Nuclear Science and Engineering | Volume 12 | Number 2 | February 1962 | Pages 238-242
Technical Paper | doi.org/10.13182/NSE62-A26063
Articles are hosted by Taylor and Francis Online.
The space energy distribution of neutrons diffusing in a source-free, nonabsorbing medium possessing a temperature gradient is obtained by solving the appropriate Boltzmann equation to a second order approximation using the expansion technique of Chapman and Enskog. The medium is assumed to possess a locally Maxwellian energy distribution and the neutron scattering is taken to be isotropic in the laboratory system of coordinates. It is found that the neutron current is increased in the direction of a negative temperature gradient and the “thermal diffusion” transport coefficient is evaluated as a function of the mass of the moderator nuclei. For the case of infinite mass nuclei, the results correspond to the kinetic theory model of a Knudsen gas in a binary Lorentzian gas mixture. An analysis of the results is carried out in the framework of the thermodynamic theory of coupled irreversible processes.