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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
R. R. Ruch, V. P. Guinn, R. H. Pinker
Nuclear Science and Engineering | Volume 20 | Number 4 | December 1964 | Pages 381-385
Technical Paper | doi.org/10.13182/NSE64-A20980
Articles are hosted by Taylor and Francis Online.
In criminal cases involving shootings, a suspect is often apprehended fleeing the scene of the crime, or is picked up at some other location shortly after the crime. In such cases it is desirable to examine the hands of the suspect to ascertain whether or not he has fired a gun recently. In the past the so-called ‘paraffin test’ has often been used in such cases. Unfortunately, evidence has long been accumulating which shows this test to be rather unreliable. At present, there is no alternate test of proven reliability. Some earlier exploratory studies, carried out by General Atomic and the Los Angeles Police Department, indicated the possibility of detecting gunpowder and/or primer-residue elements by means of neutron-activation analysis. The present study is exploring this approach further, with very promising results. Virtually all U. S. and foreign revolver ammunition contains an antimony compound in the primer of the bullet, and many also contain a barium or a lead compound. Studies in these laboratories have shown that, in all revolver ammunition examined to date, readily measurable traces (of the order of 0.2 μg) of antimony are deposted on the back of the hand each time the gun is fired. In many cases, easily measurable traces of barium are deposted (∼1 μg), while in certain cases, copper is also found (0.2–3.0 μg). A satisfactory neutron-activation procedure has been worked out which involved (1) careful removal of any possible residue from the hand, (2) activation of the removed material for 30 – 60 minutes in the TRIGA reactor at a thermal neutron flux of 1.8 × 1012 n/sec cm2, (3) radiochemical separation of any induced 2.8-daySb122, 84-minuteBa139, and 12.8-hour Cu64 activities with carriers, and (4) multichannel gamma-ray spectrometry identification and quantitative determination of each activity. Possible means of removing powder residues from skin have been explored, and several satisfactory methods are now available. The residues have not been examined for lead because of the relatively poor sensitivity for lead (∼10 μg) and because the 3.3-hour Pb209 induced activity is a pure beta emitter. The Sb, Ba, and Cu are separated from the salty solution obtained from the hand, and from one another, by postirradiation carrier precipitation of barium as BaSO4, extraction of antimony as SbCl5 with isopropyl ether (followed by conversion to aqueous Sb+++ and precipitation as elemental Sb for counting), and precipitation of copper as CuSCN. In these separations the yields are high and the procedure is rapid. The detection limits, for a one-hour irradiation at 1.8 × 1012 flux, are 0.01 μg Sb, 0.05 μg Ba, and 0.001 μg Cu. Studies to date indicate a good possibility that the activation-analysis technique will be able to show whether or not a person has fired a gun, and in some cases identify the type of ammunition as well as the number of firings. Many aspects of the over-all problem are under study, and the possible extension to cases of bombings is under consideration.
