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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Inkjet droplets of radioactive material enable quick, precise testing at NIST
Researchers at the National Institute of Standards and Technology have developed a technique called cryogenic decay energy spectrometry capable of detecting single radioactive decay events from tiny material samples and simultaneously identifying the atoms involved. In time, the technology could replace characterization tasks that have taken months and could support rapid, accurate radiopharmaceutical development and used nuclear fuel recycling, according to an article published on July 8 by NIST.
Herbert S. Wilf
Nuclear Science and Engineering | Volume 5 | Number 5 | May 1959 | Pages 306-319
Technical Paper | doi.org/10.13182/NSE59-A25603
Articles are hosted by Taylor and Francis Online.
The use of the method of discrete ordinates as a numerical tool in reactor calculations is described. A scheme for the numerical integration of the discrete ordinate equations is developed, and the results compared with known exact solutions. The problem of reflection and transmission of neutron beams in stratified slab geometry is considered from the point of view of the method of discrete ordinates. A matrix formalism is derived which permits the calculation of transmitted and reflected distributions if the incident beam is given. Asymptotic expressions for the relevant matrices are given, and comparison is made with the work of Chandrasekhar. Tables of the matrix elements in the P7 approximation are presented.
