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
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Fu-Long Chen, Shih-Hai Li
Nuclear Technology | Volume 90 | Number 2 | May 1990 | Pages 215-225
Technical Paper | Radioacitive Waste Management | doi.org/10.13182/NT90-A34416
Articles are hosted by Taylor and Francis Online.
To analytically predict the transport of radionuclides in porous media, it is necessary to develop a complete mathematical model. This means that the mechanisms must be described and the governing equations derived, along with their general solutions for the transport processes. The four major mechanisms—ad-vection, dispersion, adsorption-desorption and ion exchange, and degradation—are physically described and mathematically modeled. Based on the classic principle of mass conservation in a control volume, the governing equation for the transport of radionuclides in porous media is derived, which may be called the advection-dispersion equation. Some general solutions of the governing equation are obtained by using constant dispersion coefficients. In addition, some ambiguities of the advective-dispersion equation are solved, and this equation is extended to fractured media.
