Image: Purdue University/Maria Okuniewski

A team of researchers led by Purdue University has used X-ray imaging conducted at Argonne National Laboratory’s Advanced Photon Source to obtain a three-dimensional view of the interior of an irradiated nuclear fuel sample. The use of synchrotron micro-computed tomography could lead to more accurate modeling of fuel behavior and more efficient nuclear fuel designs, according to the researchers.

You may have read the abbreviated version of this article in the November 2020 issue of Nuclear News. Now here's the full article—enjoy!

I have enjoyed a long and stimulating career in applied nuclear physics—specifically nuclear reactor physics, nuclear fusion plasma physics, and nuclear fission and fusion reactor design—which has enabled me to know and interact with many of the scientists and engineers who have brought the field of nuclear energy forward over the past half-century. In this time I have had the fortune to interact with and contribute (directly and indirectly) to the education of many of the people who will carry the field forward over the next half-century.

The MiFi-DC as portrayed in a video released by Argonne.

Electrifying the nation’s trucking industry could reduce consumption of fossil-based diesel fuel, but it would also pose new challenges. A cross-country 18-wheel truck needs five to 10 times more electricity than an electric car to recharge its battery. Where will that electricity come from?

A team of engineers at Argonne National Laboratory has designed a microreactor called the MiFi-DC (for MicroFission Direct Current) that they say could be mass-produced and installed at highway rest stops to power a future fleet of electric 18-wheelers.

Nuclear News reached out to the MiFi-DC team to learn more. The team, led by Derek Kultgen, a principal engineer at Argonne who also leads the lab’s Mechanisms Engineering Test Loop, responded to questions by email. While they emphasized that much more needs to be done before the MiFi-DC could become a fixture at rest stops across the country, the information the team shared sheds some light on the process of designing a tiny reactor for a specific purpose.

The National Academies of Sciences, Engineering, and Medicine (NAS) has begun a new webinar series, with the first entry titled “What’s new in low-dose radiation.” The July 22 event kicked off the Gilbert W. Beebe Webinar Series—an extension of the Beebe Symposium, which was established in 2002 to honor the scientific achievements of the late Gilbert Beebe, NAS staff member and designer/implementer of epidemiologic studies of populations exposed to the atomic bombings of Hiroshima and Nagasaki as well as the Chernobyl accident.

The Ghana Research Reactor-1, located in Accra, Ghana, was converted from HEU fuel to LEU in 2017. Photo: Argonne National Laboratory

In late 2018, Nigeria’s sole operating nuclear research reactor, NIRR-1, switched to a safer uranium fuel. Coming just 18 months on the heels of a celebrated conversion in Ghana, the NIRR-1 reboot passed without much fanfare. However, the switch marked an important global milestone: NIRR-1 was the last of Africa’s 11 operating research reactors to run on high-enriched uranium fuel.

The 40-year effort to make research reactors safer and more secure by replacing HEU fuel with low-enriched uranium is marked by a succession of quiet but immeasurably significant milestones like these. Before Africa, a team of engineers from many organizations, including the U.S. Department of Energy’s Argonne National Laboratory, concluded its conversion work in South America and Australia. Worldwide, 71 reactors in nearly 40 countries have undergone conversions to LEU, defined as less than 20 percent uranium-235. Another 31 research reactors have been permanently shut down.