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.
Division Spotlight
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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!
Latest Magazine Issues
Jun 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
July 2025
Fusion Science and Technology
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.
A. Abdelghafar Galahom
Nuclear Science and Engineering | Volume 193 | Number 6 | June 2019 | Pages 638-651
Technical Paper | doi.org/10.1080/00295639.2018.1560757
Articles are hosted by Taylor and Francis Online.
This work presents a comparison between the homogeneous and heterogeneous [seed-blanket (SB)] fuel assembly used in the VVER-1200 core. The MCNPX 2.7 code with the ENDF/B-VII.0 data library was used to investigate the possible advantages that can be achieved when the SB assembly is used instead of homogeneous assembly. Thorium-232 was used as a fertile material in the blanket region and different fissile materials were investigated in the seed region. The neutronic characteristics of the presented designs were investigated by comparing four different combinations of fissile materials with (Th,U)O2 that were distributed uniformly through the whole assembly. The radial power distribution was investigated in both homogeneous and SB assemblies. The power distribution is flatter in the homogeneous assembly than the heterogeneous assembly. The suggested fuels in the SB assembly achieved a longer fuel cycle than the homogeneous assembly. Neutronic parameters related to reactor safety operation, such as control rod worth, Doppler reactivity coefficient, and effective delayed neutron fraction βeff have been investigated for the suggested fuel types. The SB assembly achieved a higher conversion ratio than the homogeneous assembly. Therefore, the fissile inventory ratio decreased more slowly with burnup in the case of SB than in the homogeneous assembly. Using 232Th instead of 238U reduced the production of the plutonium and the transuranic atoms.
