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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Candidates for leadership provide statements: ANS Board of Directors
With the annual ANS election right around the corner, American Nuclear Society members will be going to the polls to vote for a vice president/president-elect, treasurer, and members-at-large for the Board of Directors. In January, Nuclear News published statements from candidates for vice president/president-elect and treasurer. This month, we are featuring statements from each nominee for the Board of Directors.
A. W. Gray
Nuclear Technology | Volume 12 | Number 4 | December 1971 | Pages 342-347
Technical Paper | Reactor | doi.org/10.13182/NT71-A30982
Articles are hosted by Taylor and Francis Online.
An analytical study has been completed to define minimum critical mass parameters for a spherical region containing a 235U-H2O mixture reflected by a natural uranium-water mixture. The study indicates that for an optimum natural-H2O reflector, the calculated minimum critical mass for the central sphere lies in the range of 75 to 200 g of 235U. The analytic study was divided into three phases. In the first phase homogeneous two-region systems were examined using diffusion theory programs. The results indicated a minimum critical mass of 451-g 285U for an optimal system. In the second phase a Monte Carlo program was utilized to compute keff for uranium metal rod-H2O moderated lattices for which experimental data are available. The purpose of the second phase was to establish the validity of the Monte Carlo program as an analytical tool. In the third phase the Monte Carlo program was used to calculate 235U + H2O spheres closely reflected by an optimum lattice of natural uranium rods. The Monte Carlo program indicates that the minimum critical mass in an H2O-moderated system reflected by a uranium metal lattice is 135 ± 65 g 235U.
