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.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Winter Conference & Expo
November 15–18, 2026
Phoenix, AZ|Arizona Grand Resort & Spa
Latest Magazine Issues
Sep 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
October 2026
Nuclear Technology
Fusion Science and Technology
Latest News
Westinghouse, Nordion, and PSEG team up to produce Co‑60 in the United States
This past January, Westinghouse Electric Company, Nordion, and PSEG Nuclear formalized agreements to implement newly developed cobalt-60 production technology at Units 1 and 2 of PSEG’s Salem nuclear power plant in New Jersey, with the Co-60 to be supplied to Nordion. Through an ongoing joint initiative, the companies aim to harness U.S. pressurized water reactors to produce a key medical isotope and build the first commercial-scale Co-60 production platform in the United States.
F. Malvagi, G. C. Pomraning, M. Sammartino
Nuclear Science and Engineering | Volume 112 | Number 3 | November 1992 | Pages 199-214
Technical Paper | doi.org/10.13182/NSE92-A29069
Articles are hosted by Taylor and Francis Online.
We consider the problem of neutral particle transport in a stochastic Markovian mixture consisting of an arbitrary number M of immiscible fluids. The Liouville master equation is used to obtain a model for the ensemble-averaged angular flux. This model consists of M coupled transport equations. If the absorption, internal source, and temporal and spatial gradients are assumed small, this transport description can be reduced to a diffusive description. Depending upon the scaling of the Markovian transition lengths, this diffusive limit consists of either a single diffusion equation or a set of M coupled diffusion equations. The asymptotic analysis is also used to derive appropriate initial and boundary conditions for each diffusion equation.