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
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
The Frisch-Peierls memorandum: A seminal document of nuclear history
The Manhattan Project is usually considered to have been initiated with Albert Einstein’s letter to President Franklin Roosevelt in October 1939. However, a lesser-known document that was just as impactful on wartime nuclear history was the so-called Frisch-Peierls memorandum. Prepared by two refugee physicists at the University of Birmingham in Britain in early 1940, this manuscript was the first technical description of nuclear weapons and their military, strategic, and ethical implications to reach high-level government officials on either side of the Atlantic. The memorandum triggered the initiation of the British wartime nuclear program, which later merged with the Manhattan Engineer District.
H. Amano, M. Atarashi, H. Noguchi, S. Yokoyama, Y. Ichimasa, M. Ichimasa
Fusion Science and Technology | Volume 28 | Number 3 | October 1995 | Pages 803-808
Tritium Safety | Proceedings of the Fifth Topical Meeting on Tritium Technology in Fission, Fusion, and Isotopic Applications Belgirate, Italy May 28-June 3, 1995 | doi.org/10.13182/FST95-A30503
Articles are hosted by Taylor and Francis Online.
Trace amounts of elemental tritium (HT) were released continuously to the surface atmosphere at a site at Chalk River Laboratories, Canada over the 12-day period 1994 July 27 to August 8. The test area consisted of four agricultural plots, each 5 m square. One plot was left in its natural state, and the other three were cultivated. Cherry tomatoes, radishes and edible Chinese mustard (Komatsuna in Japanese) were grown in the three cultivated fields. After the HT gas reached the surface of the field, some portion of it was converted into the water form (HTO) mainly by microorganisms in the soil. Then, plant absorbs HTO from both soil and air. Photosynthesized organic material in plant contains tritium,also. The main purpose of this research is to analyze the variation with time of tissue free-water tritium (TFWT) and organically bound tritium (OBT) in several plant species during the HT release. The specific activity of HTO in plants increased rapidly after the HT exposure. The HTO concentration in plant leaves almost attained its maximum value in about 10 days, even though there were several precipitation events, which decreased the soil HTO concentration. The specific activity of OBT in plants increased gradually after the start of the exposure. The OBT concentration in plants did not attain steady state over the whole exposure period of 12 days. The OBT/HTO ratio in plants increased gradually during the release. The ratio in Komatsuna leaves changed from 0.06 to 0.24 between 2 and 11 days. The production rates of OBT in plants are fitted to numerical equations.