ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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!
Latest Magazine Issues
May 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
July 2025
Nuclear Technology
June 2025
Fusion Science and Technology
Latest News
BREAKING NEWS: Trump issues executive orders to overhaul nuclear industry
The Trump administration issued four executive orders today aimed at boosting domestic nuclear deployment ahead of significant growth in projected energy demand in the coming decades.
During a live signing in the Oval Office, President Donald Trump called nuclear “a hot industry,” adding, “It’s a brilliant industry. [But] you’ve got to do it right. It’s become very safe and environmental.”
T. Trombetti, D. L. Hetrick
Nuclear Science and Engineering | Volume 86 | Number 2 | February 1984 | Pages 129-135
Technical Paper | doi.org/10.13182/NSE84-A18195
Articles are hosted by Taylor and Francis Online.
A multinode treatment of the problem of nonlinear reactor stability is given. The nodal kinetics equations account for nodal powers, precursor concentrations, and temperatures. Nonlinear power-plus-temperature feedbacks are admitted in each node. Quadratic and logarithmic Lyapunov functions are considered. By formulating and solving a suitable nonlinear programming problem, the optimal estimate of the domain of attraction of the reactor-operating equilibrium state that can be afforded by the aforesaid V functions is explicitly constructed. An example of a reactor with two nodal power feedbacks (one destabilizing) and two destabilizing nodal temperature feedbacks is given. These feedbacks are seen to give rise to an unstable equilibrium reactor state, in the region of all-positive perturbations, which is extremely well approached by the boundary of the estimate of the domain of attraction.
