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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!
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Nuclear Science and Engineering
February 2025
Nuclear Technology
January 2025
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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?
R. W. Conn, T. Y. Sung, M. A. Abdou
Nuclear Technology | Volume 26 | Number 4 | August 1975 | Pages 391-399
Technical Paper | Reactor | doi.org/10.13182/NT75-A24440
Articles are hosted by Taylor and Francis Online.
The induced radioactivity and afterheat in five recently presented fusion reactor blanket designs have been calculated. These designs differ in the choices of structural material, coolant, and neutron multiplier. Nevertheless, the radioactivity levels at shutdown after a 2-yr operation are within a factor of 4 of each other and are clustered at ∼1 Ci/W(th). However, the long-term radioactivity (>200 yr) is greatest for niobium structures and least for aluminum. For niobium, the level of long-term activity is ∼5 × 10−5 Ci/W(th), whereas for aluminum, the level drops to ∼10−7 Ci/W(th) just several weeks after shutdown. This last result will be modified by the inclusion of trace elements and impurities. Afterheat levels are found to vary from to 5% of the thermal operating power, depending on design and the choice of structural material. Importantly, however, the afterheat power density is only ∼0.2 W/cm3 at most and this is roughly a factor of 10 to 60 less than the afterheat power density in fast breeder reactors. Biological hazard potential (BHP) values are calculated for all designs by the pessimistic approach of dividing the activity in Ci/kW(th) by the lowest maximum permissible concentration value, in Ci/km3 of air, given in U.S. Atomic Energy Commission rules, Title 10, Part 20. In all cases, the BHP nevertheless drops below 1 km3/ kW(th) 20 yr after shutdown following a 2-yr operation. The key isotopes contributing to radioactivity, afterheat, and BHP are listed for future reference.