104:. A basic requirement for the success of this method is that the axial-flow compressors successfully transmit parallel streams of different isotopic compositions without significant mixing. A typical Helikon module consists of a large cylindrical steel vessel housing the 20 separator assemblies, along with two compressors (one mounted on each end), and two water-cooled
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separation. The spiral swirling flow decays downstream of the feed inlet due to friction at the tube wall. Consequently, the inside diameter of the tube is typically tapered to reduce decay in the swirling flow velocity. This process is characterized by a separating element with a very small stage
87:. The tube tapers to a small exit aperture at one or both ends. This tangential injection of gas results in a spiral or vortex motion within the tube, and two gas streams are withdrawn at opposite ends of the vortex tube; centrifugal force providing the
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required to link stages together, the design was developed into a cascade design technique (dubbed
Helikon), in which 20 separation stages are combined into one module, and all 20 stages share a common pair of
63:. Aerodynamic enrichment processes require large amounts of electricity and are not generally considered economically competitive because of high energy consumption and substantial requirements for removal of
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Cambridge. Other methods of separation were more practical at that time, but this method was designed and used in
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is injected tangentially into a tube at one end through nozzles or holes, at velocities close to the
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thought of the idea for isotope separation and tried creating such a device in 1934 in the lab of
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content of around 3–5%, and 80–93% enriched uranium for use in
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de
Villiers, J. W.; Jardine, Roger; Reiss, Mitchell (1993).
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Uranium
Enrichment Technologies: Proliferation Implications
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Uranium Enrichment Corporation of South Africa, Ltd.
55:(UCOR) developed the process, operating a facility at
167:The Strangest Man: The Hidden Life of Paul Dirac
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129:South Africa and weapons of mass destruction
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198:"Why South Africa Gave up the Bomb"
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171:. New York: Basic Books. pp.
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