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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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
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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?
Robert E. Rothe, Donald L. Alvarez, Harold E. Clark
Nuclear Technology | Volume 25 | Number 3 | March 1975 | Pages 502-516
Technical Paper | Chemical Processing | doi.org/10.13182/NT75-A24388
Articles are hosted by Taylor and Francis Online.
Nuclear safety engineers must evaluate the criticality potential of a variety of plant problems. Many of these involve an essentially unreflected system containing uranium solution and a fixed nuclear poison. Measured critical parameters for such a system at solution concentrations of 52.2- and 141.5-g U/liter, together with those reported previously at 450.8-g U/liter, provide the engineer information over a wide range of concentrations normally encountered in industrial applications. The uranium was enriched to 93.24 wt% 235U. The fixed poison was 1.02 wt% natural boron alloyed in stainless-steel plates. Critical solution heights were measured for various numbers of nearly uniformly spaced vertical plates within the 106.6-cm-diam experimental tank. The simplest cases studied involved no poison, resulting in low critical heights. As plates were added, the critical height increased until a sufficient number were present that even an infinitely tall tank would have been subcritical. The actual finite plate height permitted a third type of experimental result: the critical parameters of an unpoisoned uranium solution slab on top of a highly poisoned solution region. Experimental data at all three concentrations compared with results from Monte Carlo and neutron transport computer codes are found to predict critical heights consistently in excess of measured values. A nuclear safety engineer may safely apply these calculational methods to similar plant situations provided an ∼20% reduction in either the solution height or plate spacing— whichever is appropriate—is made to account for the theory/experiment difference. Boron-containing plates are compared with borosilicate glass Raschig rings as fixed nuclear poisons for large-volume solution storage. Neither is clearly superior to the other considering the poison volume percent required for criticality. Nuclear safety engineers may safely apply these experimental poison plate data to standard ringpoisoned systems involving a high-concentration uranium solution provided a 2% increase in the boron density is made to account for uncertainties in the comparison.