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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.
Javiera Cervini-Silva
Nuclear Technology | Volume 210 | Number 8 | August 2024 | Pages 1487-1495
Note | doi.org/10.1080/00295450.2023.2295152
Articles are hosted by Taylor and Francis Online.
Bentonites are natural reservoirs of various elements and are of interest because they are sources of thorium and uranium, which are transition elements that provide nuclear energy. The objective of this work was to study the plausible association(s) of these elements with other transition elements of interest. The contents of 18 transition elements (cerium, cobalt, chromium, copper, iron, hafnium, lanthanum, manganese, molybdenum, neodymium niobium, nickel, tantalum, thorium, uranium, vanadium, yttrium, zinc, and zirconium) in 38 bentonites determined experimentally by X-ray fluorescence spectroscopy (XRF) were analyzed.
The contents of the elements were plotted in (x,y) graphs and then fitted to polynomial functions (orders 1 through 6). According to the coefficient of determination (r2: 0.5 ≤ r2 strong, 0.3 ≤ r2 ≤ 0.5 medium, and r2 ≤ 0.3 weak), the contents of thorium, uranium, niobium, and nickel related strongly, thus the presence of niobium and nickel served to predict the presence of detectable concentrations of thorium and uranium. The equations showing higher r2 values were
1. {Th} = 1e-6{Nb}5 − 3e-4{Nb}4 + 1.9e-2{Nb}3 − 5.4e-1{Nb}2 + 7.3{Nb} − 6.3, r2 = 0.53.
2. {Th} = −3e-8{Nb}6 + 9e-6{Nb}5 − 1e-3{Nb}4 + 4.7e-2{Nb}3 − 1.1{Nb}2 + 11.5{Nb} − 16, r2 = 0.54.
3. {Th} = 5e-6{Ni}4 − 1.5e-3{Ni}3 − 1.5e-1{Ni}2 − 5.8{Ni} + 9e+1, r2 = 0.49.
4. {Th} = −7e-8{Ni}5 + 3e-5{Ni}4 − 5.1e-3{Ni}3 + 3.4e-1{Ni}2 − 9.5{Nb} + 1e+2, r2 = 0.56.
5. {Th} = 2e-9{Ni}6 − 8e-7{Ni}5 + 2e-4{Ni}4 − 1.5e-2{Ni}3 − 7e-1{Ni}2 − 1e+1{Ni} + 1e+1, r2 = 0.60.
6. {Th} = −1e-4{U}5 + 1.3e-2{U}4 − 4.3e-1{U}3 + 5.7e-1{U}2 − 2e+1{U} + 5e+1, r2 = 0.54.
7. {Th} = 6e-6{U}6 − 9e-4{U}5 + 4.5e-2{U}4 − 1.1{U}3 + 1e+1{U}2 − 5e+1{U} + 1e+2, r2 = 0.64.
8. {U} = 8e-6{Nb}4 − 1.2e-3{Nb}3 + 4.8e-2{Nb}2 − 4.3e-1{Nb} + 6.8, r2 = 0.48.
9. {U} = 2e-7{Nb}5 − 4e-5{Nb}4 + 2.8e-3{Nb}3 − 7.6e-2{Nb}2 + 1.1{Nb} + 1.9, r2 = 0.5.
10. {U} = 1e-8{Nb}6 − 3e-6{Nb}5 + 2e-4{Nb}4 − 8e-3{Nb}3 + 1.3e-1{Nb}2 − 5.4e-1{Nb} + 5.4, r2 = 0.51.
11. {U} = 1.8e-1{Th} + 2.6, r2 = 0.49; {U} = 1.7e-3{Th}2 − 2.9e-2{Th} + 6.3, r2 = 0.60.
12. {U} = 2e-5{Th}3 − 1.7e-3{Th}2 + 1.4e-1{Th} + 4.5, r2 = 0.58; {U} = −5e-7{Th}4 + 2e-4{Th}3 − 1.5e-2{Th}2 + 5.5e-1{Th} + 1.5, r2 = 0.6.
13. {U} = −7e-9{Th}5 + 2e-6{Th}4 − 1e-4{Th}3 − 3e-4{Th}2 + 2.7e-1{Th} + 2.9, r2 = 0.6.
14. {U} = 2e-9{Th}6 − 8e-7{Th}5 + 1e-4{Th}4 − 8.1e-3{Th}3 − 2.4e-1{Th}2 + 15, r2 = 0.65.
This study provided a joint experimental and theoretical approach to optimize the recovery of thorium and uranium and to save invaluable onsite and off-site natural resources and work time. The findings might expand on other studies reporting the quantification of transition metals on bentonite matrices. For instance, the concentrations of nickel reported in studies using bench techniques could serve as the basis to calculate the contents of thorium.
