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Emerging Biomedical Analysis
Published in Lawrence S. Chan, William C. Tang, Engineering-Medicine, 2019
In the following three decades, the mass spectrometer was redesigned by Francis W. Aston, Arthur J. Dempster, Kenneth T. Bainbridge, Ernest O. Lawrence and other scientists to improve the resolving power (Audi 2006). However, at that stage, mass spectrometers were predominantly used by physicists to prove the existence of elemental isotopes or to separate an isotope from its natural mixture. The most famous application during this period was the use of the mass spectrometer in the Manhattan Project in World War II. In the Manhattan Project, Ernest O. Lawrence, who received the Nobel Prize in Physics in 1939 for his invention of the cyclotron, developed the calutron to prepare high-purity uranium-235 (Parkins 2005).
Uranium Enrichment
Published in Kenneth D. Kok, Nuclear Engineering Handbook, 2016
Nathan (Nate) Hurt, Kenneth D. Kok
Calutrons are electromagnetic isotope separators that operate like analytical mass spectrometers. The term calutron is a tribute to the work of E. O. Lawrence and his team of scientists who developed the process at their University of California cyclotron laboratory and assisted in its transformation to a production-scale process at the electromagnetic plant located at the Y-12 site in Oak Ridge, Tennessee. The Y-12 calutron process was replaced shortly after the end of World War II by the gaseous diffusion process located at the K-25 plant (also in Oak Ridge). The gaseous diffusion operation had much larger production capabilities and was far less labor intensive.
Light, the universe and everything – 12 Herculean tasks for quantum cowboys and black diamond skiers
Published in Journal of Modern Optics, 2018
Girish Agarwal, Roland E. Allen, Iva Bezděková, Robert W. Boyd, Goong Chen, Ronald Hanson, Dean L. Hawthorne, Philip Hemmer, Moochan B. Kim, Olga Kocharovskaya, David M. Lee, Sebastian K. Lidström, Suzy Lidström, Harald Losert, Helmut Maier, John W. Neuberger, Miles J. Padgett, Mark Raizen, Surjeet Rajendran, Ernst Rasel, Wolfgang P. Schleich, Marlan O. Scully, Gavriil Shchedrin, Gennady Shvets, Alexei V. Sokolov, Anatoly Svidzinsky, Ronald L. Walsworth, Rainer Weiss, Frank Wilczek, Alan E. Willner, Eli Yablonovitch, Nikolay Zheludev
There is another feature of atoms which has no parallel with electrons or photons: isotopes of the elements. Here, it is the nuclear properties of the atoms that are important, determined by a different number of neutrons in the nucleus. Most elements in the periodic table have multiple stable isotopes, while radioisotopes are created by nuclear transmutation or fission. Isotopes are a great natural resource, with life-saving applications in healthcare, such as imaging of disease, targeted cancer therapy and diagnosis of malnutrition with stable tracers. Isotopes are also used in industry, for instance, for oil and gas exploration, and for national security in detecting dangerous materials. While there are already great applications in technology, isotopes are still a mostly untapped resource owing to the difficulty and cost of separation. The main method used today, the Calutron, was invented in the 1930s, and is very inefficient and expensive. This method relies on ionization of neutral atoms by electron bombardment, and separation by charge-to-mass ratio [156]. The only large-scale Calutrons in operation today are in Russia, and even these machines were built over 60 years ago. A new method was recently developed that is much more efficient than the Calutron, and will make isotopes readily available for technology. This method, Magnetically Activated and Guided Isotope Separation (MAGIS) relies on optical pumping of atomic beams and separation by magnetic-moment-to-mass ratio in a novel guide of permanent magnets [168]. This is more than just a long-term dream: the method will soon be implemented at a non-profit entity, the Pointsman Foundation, which will produce isotopes for medicine [53]. Within the next five years, production lines should be completed, assuring a worldwide supply of key isotopes. One example is Ytterbium-176, which is the stable precursor of the radioisotope Lutetium-177, a most promising agent in targeted cancer therapy. Beyond existing uses of isotopes, new applications are under development. These include imaging and treatment of heart disease with targeted radioisotopes, and inhibition of biofilms with pure beta emitters to reduce infection. We are on the cusp of an exciting era in which atomic isotopes will drastically improve our lives.