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
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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
Jan 2025
Jul 2024
Latest Journal Issues
Nuclear Science and Engineering
February 2025
Nuclear Technology
January 2025
Fusion Science and Technology
Latest News
Reboot: Nuclear needs a success . . . anywhere
The media have gleefully resurrected the language of a past nuclear renaissance. Beyond the hype and PR, many people in the nuclear community are taking a more measured view of conditions that could lead to new construction: data center demand, the proliferation of new reactor designs and start-ups, and the sudden ascendance of nuclear energy as the power source everyone wants—or wants to talk about.
Once built, large nuclear reactors can provide clean power for at least 80 years—outlasting 10 to 20 presidential administrations. Smaller reactors can provide heat and power outputs tailored to an end user’s needs. With all the new attention, are we any closer to getting past persistent supply chain and workforce issues and building these new plants? And what will the election of Donald Trump to a second term as president mean for nuclear?
As usual, there are more questions than answers, and most come down to money. Several developers are engaging with the Nuclear Regulatory Commission or have already applied for a license, certification, or permit. But designs without paying customers won’t get built. So where are the customers, and what will it take for them to commit?
K. Subba Rao, M. Srinivasan
Nuclear Technology | Volume 49 | Number 2 | July 1980 | Pages 315-320
Technical Note | Reactor | doi.org/10.13182/NT80-A32493
Articles are hosted by Taylor and Francis Online.
BeH2 could serve as an effective moderator in reducing critical masses in minimum critical mass systems on account of its (n,2n) reactivity bonus and the possibly higher hydrogen atomic density. A parametric study of the variation of keff and critical mass with BeH2 moderator density in the range of 600 to 1000 kg/m3 for the three main fissile nuclides of 235U, 233U, and 239Pu in small spherical thermal assemblies indicates that for 0.40-m-thick BeO-reflected spherical systems with BeH2 moderator of density ≥680 kg/m3 the critical masses are lower than with any other known moderator (such as H2O or CH2). With a moderator of crystalline BeH2 having a density of 780 kg/m3, critical masses are found to be lower than with CH2 by about 15%.
