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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NN Asks: What did you learn from ANS’s Nuclear 101?
Mike Harkin
When ANS first announced its new Nuclear 101 certificate course, I was excited. This felt like a course tailor-made for me, a transplant into the commercial nuclear world. I enrolled for the inaugural session held in November 2024, knowing it was going to be hard (this is nuclear power, of course)—but I had been working on ramping up my knowledge base for the past year, through both my employer and at a local college.
The course was a fast-and-furious roller-coaster ride through all the key components of the nuclear power industry, in one highly challenging week. In fact, the challenges the students experienced caught even the instructors by surprise. Thankfully, the shared intellectual stretch we students all felt helped us band together to push through to the end.
We were all impressed with the quality of the instructors, who are some of the top experts in the field. We appreciated not only their knowledge base but their support whenever someone struggled to understand a concept.
Drew E. Kornreich
Nuclear Technology | Volume 181 | Number 2 | February 2013 | Pages 282-302
Technical Paper | Reactor Safety | doi.org/10.13182/NT13-A15784
Articles are hosted by Taylor and Francis Online.
This work involved estimating the homogeneous metal-water mixture critical mass curves of 34 fissionable nuclides from thorium to einsteinium. Calculations were performed using the discrete ordinates code PARTISN with ENDF/B-VII.0 69-group cross sections. Sample MCNP5 test cases indicate reasonable agreement between the two transport codes. In general, the results confirmed that there are three "forms" of the critical mass curves: (a) the traditional curve most well known as characterizing the "big 3" nuclides (233U, 235U, 239Pu), where the minimum critical mass is found in a dilute solution; (b) a simple monotonic curve characterized by a monotonically increasing critical mass as water is added to the metal, where the minimum critical mass is a metal system; and (c) a hybrid curve where the shape is similar to the traditional curve but the minimum critical mass is the pure metal. In general, the traditional and monotonic curves follow the "odd-even" rule of thumb that a nuclide with an even Z and an odd A or vice versa will have a traditionally shaped curve and that the other nuclides will have a monotonically shaped curve. The violations of this rule of thumb, i.e., the hybrid curves, in the set of nuclides analyzed are comprised of 232U and 252Cf. Plutonium-236 is especially interesting because it is a traditionally shaped curve with the minimum critical mass in a relatively dilute solution, but it violates the "odd-even" rule of thumb.