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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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BREAKING NEWS: Trump issues executive orders to overhaul nuclear industry
The Trump administration issued four executive orders today aimed at boosting domestic nuclear deployment ahead of significant growth in projected energy demand in the coming decades.
During a live signing in the Oval Office, President Donald Trump called nuclear “a hot industry,” adding, “It’s a brilliant industry. [But] you’ve got to do it right. It’s become very safe and environmental.”
Y. Harima, S. Tanaka
Nuclear Science and Engineering | Volume 90 | Number 2 | June 1985 | Pages 165-173
Technical Paper | doi.org/10.13182/NSE85-A17674
Articles are hosted by Taylor and Francis Online.
Exposure buildup factors for plane isotropic, point isotropic, and plane normal sources have been calculated using a discrete ordinates direct integration code, PALLAS-PL, SP-Br, in infinite and finite water shields in the 0.06- to 0.1-MeV range. The values of the attenuation kernel, Be-µr, are greater than unity at distances up to a few mean-free-paths in an infinite medium. The maximum value of Be-µr depends on the incident energy, and this effect reaches a maximum for a 0.08-MeV source. The implication that the dose rate with a shield is greater than without a shield should be noticed. Results of this study show, however, that the large degree of scattering in a low-z material, such as water, produces this effect. Buildup factors, energy spectra, and angular distributions were analyzed for three source geometries in the comparisons of scattered gamma-ray transport in infinite and finite water shields.