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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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How to talk about nuclear
In your career as a professional in the nuclear community, chances are you will, at some point, be asked (or volunteer) to talk to at least one layperson about the technology you know and love. You might even be asked to present to a whole group of nonnuclear folks, perhaps as a pitch to some company tangential to your company’s business. So, without further ado, let me give you some pointers on the best way to approach this important and surprisingly complicated task.
Weston M. Stacey, Jr.
Nuclear Science and Engineering | Volume 48 | Number 4 | August 1972 | Pages 444-458
Technical Paper | doi.org/10.13182/NSE72-A22512
Articles are hosted by Taylor and Francis Online.
A variational theory is developed for estimating reactivity worths (and other bilinear ratios) and reaction rate ratios in critical nuclear reactors. These estimates embody corrections to first-order perturbation theory which account for the flux change caused by the reactivity perturbation and for the changes in the flux and adjoint when the system is altered. The physical significance of certain generalized functions which arise in the development of the theory is investigated. The relation of the variational theory to generalized perturbation theory is examined, and the additional restrictions required to reduce the former to the latter are established. Finally, the variational theory is demonstrated to yield accurate estimates for reactivity worths and reaction rate ratios in a fast reactor model, subject to a wide range of alterations in nuclear properties and compositions.