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
Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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
General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
J. P. Stora
Nuclear Technology | Volume 17 | Number 3 | March 1973 | Pages 225-233
Technical Paper | Material | doi.org/10.13182/NT73-A31266
Articles are hosted by Taylor and Francis Online.
A survey has been made of equations for calculating the thermal conductivity of two-phase solid bodies based on Ohm’s law and the flux laws. Most of these equations can be reduced to the Fricke relationship for a two-phase medium containing the second phase as randomly distributed ellipsoids. Fricke’s relationship is applied to porous uranium dioxide and to cermets UO2-metal with a structural orientation. First of all, in the case of UO2, Loeb’s formula based on Ohm’s law is considered. Although physically inadequate, this formula is easily handled and used by almost all of the investigators: the thermal conductivity of UO2 is corrected by introducing an empirical factor a multiplying the whole porosity of the oxide; a is generally determined by experimental measurements. The most probable value for α is 2.3 ± 0.5. By using the Fricke equation the a factor is justified and calculated. Second, the thermal conductivity of UO2-Fe, and UO2-Ni, containing 10, 20, and 30% metal by weight, is calculated, according to the parallel and perpendicular directions of “metallic veins,” using the Fricke mixture equation. Finally. the calculated values are compared with the experimental thermal dif-fusivity data measured along the two previous directions. The Fricke two-phase equation is found not to agree experimentally, especially at low temperatures. This discrepancy is probably due to the insufficiently precise mathematical formulation.