ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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!
Latest Magazine Issues
Dec 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
December 2025
Nuclear Technology
Fusion Science and Technology
November 2025
Latest News
Perpetual Atomics, QSA Global produce Am fuel for nuclear space power
U.K.-based Perpetual Atomics and U.S.-based QSA Global claim to have achieved a major step forward in processing americium dioxide to fuel radioisotope power systems used in space missions. Using an industrially scalable process, the companies said they have turned americium into stable, large-scale ceramic pellets that can be directly integrated into sealed sources for radioisotope power systems, including radioisotope heater units (RHUs) and radioisotope thermoelectric generators (RTGs).
Hiroshi Maekawa, Yasushi Seki, Toru Hiraoka, Masatoshi Moriyama
Nuclear Science and Engineering | Volume 57 | Number 4 | August 1975 | Pages 335-340
Technical Notes | doi.org/10.13182/NSE75-A15426
Articles are hosted by Taylor and Francis Online.
Spherical lithium-metal assemblies with and without a graphite reflector were prepared by stacking lithium arid graphite blocks to investigate the neu-tronics in the fusion reactor blanket. The ratio of 238 U-to-285U fission rates was measured by micro -fission chambers. The fission ratio was calculated by the one-dimensional transport code ANISN with the Pg-Sg approximation using a 42-group neutron cross-section set. The fission ratios measured in the lithium-metal assembly without a graphite reflector agree well with the calculated ones. In the assembly with a graphite reflector, however, there is a large discrepancy between experiment and calculation.
