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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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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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Three nations, three ways to recycle plastic waste with nuclear technology
Plastic waste pollutes oceans, streams, and bloodstreams. Nations in Asia and the Pacific are working with the International Atomic Energy Agency through the Nuclear Technology for Controlling Plastic Pollution (NUTEC Plastics) initiative to tackle the problem. Launched in 2020, NUTEC Plastics is focused on using nuclear technology to both track the flow of microplastics and improve upstream plastic recycling before discarded plastic can enter the ecosystem. Irradiation could target hard-to-recycle plastics and the development of bio-based plastics, offering sustainable alternatives to conventional plastic products and building a “circular economy” for plastics, according to the IAEA.
V. K. Paré, J. T. Mihalczo
Nuclear Science and Engineering | Volume 56 | Number 2 | February 1975 | Pages 213-218
Technical Note | doi.org/10.13182/NSE75-A26662
Articles are hosted by Taylor and Francis Online.
A theory is developed for the cross-power spectral densities between the signal from an ionization chamber containing a 252Cf neutron source, which provides the initiation of fission chains in a reactor or neutron multiplying assembly, and the signals from detectors of particles from fission chains in the reactor. Previously derived spectral densities between two detectors are modified to include the effects of the inherent and 252Cf source in the reactor. Calculations of the amplitude of the coherence function for noise measurements, both conventional and 252Cf, for the reactor at the Fast Flux Test Facility are presented and can be used to estimate the time required for a measurement with a given precision. The equivalence between the expressions developed here and those previously developed for time-domain measurements of this type is also shown. Use of a 252Cf chamber makes possible a new method of determination of the reactivity which is independent of the inherent source strength and detection efficiency. This method does not require a calibration near delayed criticality as do the previously used methods such as break frequency or coherence amplitude noise analysis and modified source multiplication measurements. It requires the knowledge of some properties of the ionization chamber containing 252Cf which can be determined outside the reactor. Since this method does not require a calibration near delayed criticality, it may be used in the initial loading of a reactor to determine the reactivity before criticality is achieved. The independence of detection efficiency also makes it useful during initial loading, since large changes in detection efficiency can occur with loading. The independence of the method on the inherent source would be advantageous during refueling of a reactor when the inherent source in the fresh fuel inserted may be much less than that of the burnt-up fuel removed. The method may also be useful in determining the reactivity of assemblies where sufficient fuel to achieve criticality is not available.
