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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
J. Schlösser
Nuclear Science and Engineering | Volume 24 | Number 2 | February 1966 | Pages 123-132
Technical Paper | doi.org/10.13182/NSE66-A18297
Articles are hosted by Taylor and Francis Online.
A model of parallel capillaries with different diameters has been developed to explain back-diffusion experiments on four rather different graphites both impregnated and unimpregnated. The transport phenomenon has been taken as an interaction between diffusional and molecular flow on one hand, and viscous and slip flow on the other, to cover the whole range of diameter to mean-free-path ratios possible in graphite. It can be shown that only by assuming at least three bundles of capillaries with different diameters can these experiments be adequately explained. It is further possible to relate the material constants, the viscous flow component B0, and the slip flow component K0 to the pore-size distribution obtained. When we consider the complexity of porous capillaries in graphite, the agreement is found to be good, about 30%.
