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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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A webinar, and a new opportunity to take ANS’s CNP Exam
Applications are now open for the fall 2025 testing period for the American Nuclear Society’s Certified Nuclear Professional (CNP) exam. Applications are being accepted through October 14, and only three testing sessions are offered per year, so it is important to apply soon. The test will be administered from November 12 through December 16. To check eligibility and schedule your exam, click here.
In addition, taking place tomorrow (September 19) from 12:00 noon to 1:00 p.m. (CDT), ANS will host a new webinar, “How to Become a Certified Nuclear Professional.” More information is available below in this article.
Toru Obara, Hiroshi Sekimoto
Nuclear Science and Engineering | Volume 130 | Number 3 | November 1998 | Pages 386-390
Technical Note | doi.org/10.13182/NSE98-A2014
Articles are hosted by Taylor and Francis Online.
The positive neutron temperature coefficient of reactivity of a dilute plutonium-water solution is discussed analytically and numerically. It is explained by the competition of the temperature sensitivity coefficients of microscopic thermal cross sections of fissile materials and absorbers. The use of 176Lu, 180Ta, or 167Er, which have absorption resonances at low energy, in the solution makes it possible for the neutron temperature coefficient of reactivity of a dilute plutonium-water solution to be negative.
