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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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Latest News
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.
Herbert Rief
Nuclear Science and Engineering | Volume 10 | Number 1 | May 1961 | Pages 83-89
Technical Paper | doi.org/10.13182/NSE61-A25934
Articles are hosted by Taylor and Francis Online.
A Monte Carlo code is used to calculate the fast effect in both homogeneous and heterogeneous systems. The following results are obtained: for an infinite block of natural uranium, δ28 = 0.39, ∈ = 1.247; for an infinite block of beryllium, ∈ = 1.078; for beryllium oxide, ∈ = 1.046. In addition, results are given for homogeneous mixtures of uranium and beryllium. Calculations have also been carried out for uranium-water lattices and compared with experimental results for slightly enriched uranium rods and slabs, and uranium oxide rods. Other results show the increase in ∈ when uranium fuel elements are surrounded by beryllium cladding of varying thickness.