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
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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
Oct 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
November 2025
Nuclear Technology
Fusion Science and Technology
Latest News
Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
Kohtaro Ueki, Yuichi Ogawa, Hiroshi Naito, Tomonori Hyodo
Fusion Science and Technology | Volume 7 | Number 1 | January 1985 | Pages 90-98
Technical Paper | Shielding | doi.org/10.13182/FST85-A24521
Articles are hosted by Taylor and Francis Online.
A 14-MeV neutron streaming through a narrow vertical hole duct in the diagnostics room of a Deuterium-Tritium Fusion Experimental Device (R tokamak) was analyzed using the Monte Carlo coupling technique. Neutron dose rate distributions in the horizontal direction as well as in the axial direction along the vertical hole duct were calculated to evaluate the neutron streaming effect through the hole duct. The dose rate distribution in the axial direction undergoes relatively small changes, but the distribution changed abruptly in the horizontal direction. Compared to ANISN results, Monte Carlo calculations show a neutron streaming effect at locations beyond the vertical hole duct axis in the horizontal direction. The fractional standard deviation (FSD) due to error propagation was calculated by the ORION code based on an error propagation equation. The FSDs were within 0.06 at the detector locations along the axial direction along the vertical hole duct; but, they were as much as 0.25 to 0.47 for >15 cm beyond the hole duct axis in the horizontal direction.
