The Carolinas-Virginia Tube Reactor site, circa 1963. (Photo: Duke Energy)
The Carolinas-Virginia Tube Reactor (CVTR), also known as Parr due to its location in Parr, S.C., was a 65-MWt (17-MWe) pressurized tube reactor. Construction began in January 1960, and the reactor reached initial criticality in March 1963. Commercial operation commenced in December 1963, and the reactor was permanently shut down in January 1967 after the test program was complete.
SHINE’s isotope production building, called the Chrysalis, under construction in October 2022.
In a former farm field just outside the historic town of Janesville in south-central Wisconsin, a large concrete-and-steel building is taking shape. Dubbed the Chrysalis, the building will eventually house eight accelerator-based neutron generators, which start-up company SHINE Technologies will use to produce molybdenum-99. As the precursor to the medical radioisotope technetium-99m, Mo-99 is used in tens of millions of diagnostic procedures every year, primarily as a radioactive tracer.
At the heart of the Chrysalis will be the high-flux neutron generators, being supplied by SHINE’s sister company, Phoenix. The compact accelerators use a deuterium-tritium fusion process to produce neutrons, which in turn induce a subcritical fission reaction in an aqueous low-enriched uranium target (19.75 percent uranium-235) to produce Mo-99.
Artist’s view of heavy water eliciting sweet taste in humans. Graphic design: Tomáš Bello/IOCB Prague
Is isotope science all sweetness and light? Recent headlines on research confirming the sweet taste of heavy water and the creation of the lightest isotope of uranium yet may give that impression. But the serious science behind these separate research findings has implications for human health and for the understanding of the process of alpha decay.
Scientists studied the migration of six butterflies (from top left to bottom right): American Snout butterfly, Queen butterfly, Cloudless Sulphur butterfly, Empress Leilia butterfly, Variegated Fritillary butterfly, and Southern Dogface butterfly. (Composite photo: IAEA; photo credits: S. Bright, V. Charny, J. Gallagher, J. Green)
While scientists can tag migrating birds, mammals, and other animals to track their movements, the precise migration patterns of butterflies and other insects too small for tagging evaded scientists’ scrutiny for decades. That changed in 1996, when Leonard Wassenaar and Keith Hobson, working at the time as isotope scientists for Environment Canada, demonstrated that isotopic techniques could be used to determine the origin of individual monarch butterflies and deduce the species’ annual migration routes. Now, the same technique is being used to study other butterfly species.