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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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Latest News
Germany’s Unterweser completes removal of steam generators
All four steam generators at Germany’s Unterweser nuclear power plant have been removed from the reactor building, plant owner PreussenElektra has announced. The single-unit pressurized water reactor was shut down in 2011 as part of Germany’s decision to phase out nuclear energy. Decommissioning and dismantlement of the reactor began soon after PreussenElektra was granted a permit for the work in February 2018.
Mohamed A. Abdou, Jungchung Jung
Nuclear Technology | Volume 35 | Number 1 | August 1977 | Pages 51-79
Technical Paper | Reactor | doi.org/10.13182/NT77-A31850
Articles are hosted by Taylor and Francis Online.
Detailed nuclear analysis of a reference conceptual design for a tokamak experimental power reactor (EPR) is presented. The reference EPR has a 6.25-m major radius and a 2.1-m minor radius circular plasma with a nominal neutron wall loading of 0.5 MW/m2. A 0.28-m-thick blanket of stainless steel surrounds a stainless-steel vacuum vessel. The inner shield consists of stainless steel and B4C and is 0.58 m thick. The 0.97-m-thick outer shield employs lead mortar, stainless steel, and graphite. The neutronics results in the first wall and blanket vary significantly in the poloidal direction due to an outward shift in the deuterium-tritium neutron source distribution and the toroidal curvature. The infinite cylinder approximation overestimates response rates in the first wall compared with toroidal geometry calculations. Neutral beam lines, vacuum ducts, and other penetrations of the blanket and bulk shield represent large (∼0.6- to 1.0-m2 cross section) streaming paths for neutrons and require special shielding. A special 0.75-m-thick annular shield surrounds the neutral beam duct after it exits from the bulk shield and extends beyond the toroidal field coil and out to the beam injectors. A pneumatically operated movable shield plug, opening during the pumpdown phase and closing during the plasma burn, is selected as the principal design option for shielding the evacuation ducts.
