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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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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
P. F. Nichols
Nuclear Science and Engineering | Volume 17 | Number 1 | September 1963 | Pages 144-148
Technical Paper | doi.org/10.13182/NSE63-A17219
Articles are hosted by Taylor and Francis Online.
Reactivity measurements have been made in the Physical Constants Testing Reactor (PCTR) on a series of plutonium-aluminum rods with 0.65 in. diam and 31.00 in. long. The samples were contained in a cadmium cover during the measurements. The series of rods consisted of eight sets of two rods each. Two separate batches of plutonium with different isotopic compositions were used in the two rods within a set. The concentrations of plutonium in the alloys were adjusted in such a manner that (1) the two rods within a set differed effectively only in Pu240 content, and (2) the rod with the most Pu240 in one set had the same quantity of Pu240 as the rod with the least Pu240 in an adjacent set. The difference in reactivity measured between the rods in a set is the result of different resonance absorption rates in Pu240 in the two rods. The sensitivity of the reactor to epicadmium absorption in Pu240 was obtained by calibrating the system with three sets of rods that were all very nearly dilute in Pu240 concentration. The experimental data yield effective resonance integrals of Pu240 for the remaining rods relative to the dilute resonance integral. The value of the effective resonance integral for the rod with the highest concentration of Pu240 is a factor of about seven smaller than the dilute integral.
