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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.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Latest News
Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Masahide Imasaki and Torao Yanaru
Nuclear Science and Engineering | Volume 33 | Number 1 | July 1968 | Pages 93-105
Technical Paper | doi.org/10.13182/NSE68-A20921
Articles are hosted by Taylor and Francis Online.
The stability of flux-shaped spatial modes is studied in a Calder Hall type reactor in three dimensions using the homogeneous boundary condition of the reactivity with the following three results: 1) the modal interaction due to coolant flow is also a second-order term in the three-dimensional modal analysis and can be ignored as the first approximation; 2) the Nyquist criterion should be applied to the expression containing the involved transcendental function in the transfer function of the thermal system; and 3) the simple thermal model, which treats only the fuel, moderator, and coolant, is adequate to judge the stability of the mode. The effects of flattening the radius on the threshold value of the moderator reactivity temperature coefficient and on the period of the sustained oscillation have been studied by this method as a function of the eigenvalue, and it has been shown that: 1) the modes with the same order in axial and radial direction form a group; and 2) the modes with the second order in axial direction are more stable than the modes with the first order in axial direction.