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
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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Nuclear Science and Engineering
February 2025
Nuclear Technology
January 2025
Fusion Science and Technology
Latest News
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.
J. Devooght
Nuclear Science and Engineering | Volume 67 | Number 2 | August 1978 | Pages 147-161
Technical Paper | doi.org/10.13182/NSE78-A15432
Articles are hosted by Taylor and Francis Online.
The spectrum of the multigroup-multipoint operator with delayed neutrons is studied under the assumption of a common fission spectrum. Using the fact that the fission operator is proportional to a projector, the Weinstein-Aronszajn technique for degenerate perturbation can be used. The general problem is first reduced to a problem without delayed neutrons. The high degeneracy of the spectrum is further examined and connected with the definition of “clusters.”