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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
Meeting 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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A look inside NIST’s work to optimize cancer treatment and radiation dosimetry
In an article just published by the Taking Measure blog of the National Institute of Standards and Technology, Stephen Russek—who leads the Imaging Physics Project in the Magnetic Imaging Group at NIST and codirects the MRI Biomarker Measurement Service—describes his team’s work using phantom stand-ins for human tissue.
Farzad Rahnema, Piero Ravetto
Nuclear Science and Engineering | Volume 128 | Number 2 | February 1998 | Pages 209-223
Technical Paper | doi.org/10.13182/NSE98-A1952
Articles are hosted by Taylor and Francis Online.
It is shown that a perturbation in the external boundary of a system can be converted into (treated as) a perturbation in the boundary condition of the neutron balance equation. As a result, one may then use existing boundary condition perturbation or variational methods to estimate the change in the parameters of interest. The equivalent perturbation in the boundary condition is derived both in transport theory and its diffusion approximation for eigenvalue as well as fixed-source problems. Generalized boundary conditions in both diffusion and transport theory are considered. The existence of a solution to the problem with the equivalent boundary conditions that are nonstandard is investigated through analytic examples. The analysis is limited to first-order perturbation theory.