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CROCUS

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Research reactors are nuclear fission -based nuclear reactors that serve primarily as a neutron source . They are also called non-power reactors , in contrast to power reactors that are used for electricity production , heat generation, or maritime propulsion .

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12-471: CROCUS is a research reactor at École Polytechnique Fédérale de Lausanne , a research institute and university in Lausanne , Switzerland . The uranium nuclear reactor core is in an aluminium container that measures 130 centimetres (51 in) across with 1.2-centimetre (0.47 in)-thick walls. The aluminum vessel is filled with demineralized light water to serve as both a neutron moderator and

24-409: A moderator is required to slow the neutron velocities and enhance fission. As neutron production is their main function, most research reactors benefit from reflectors to reduce neutron loss from the core. The International Atomic Energy Agency and the U.S. Department of Energy initiated a program in 1978 to develop the means to convert research reactors from using highly enriched uranium (HEU) to

36-407: A neutron reflector . Power output is controlled either by adjusting the water level in the reactor—with a ±0.1-millimetre (0.0039 in) level of control, or with the adjustment of two boron carbide (B 4 C) control rods —with a ±1-millimetre (0.039 in) level of finesse. The reactor has six separate safety systems: two cadmium shields and four storage tanks , any of which can shut down

48-583: A few companies that concentrate the key projects on a worldwide basis. The most recent international tender (1999) for a research reactor was that organized by the Australian Nuclear Science and Technology Organisation for the design, construction and commissioning of the Open-pool Australian lightwater reactor (OPAL). Four companies were prequalified: Atomic Energy of Canada Limited (AECL), INVAP , Siemens and Technicatom . The project

60-695: Is a statutory body of the Australian Government that is responsible for nuclear research and the production of radioisotopes for nuclear medicine . It was established in April 1987 to replace the former Australian Atomic Energy Commission (AAEC), which was founded in 1952. Its headquarters and main research facilities are on the southern outskirts of Sydney in Lucas Heights , Sutherland Shire . The Australian Nuclear Science and Technology Organisation Act 1987 (Cth) prescribes its general purpose. ANSTO

72-481: Is governed by The Hon Dr Annabelle Bennett. Penelope Dobson is the deputy chair. The CEO, Shaun Jenkinson, manages the organisation. ANSTO operates five research facilities: Major research instruments include: ANSTO also manufactures radiopharmaceuticals and performs commercial work such as silicon doping by nuclear transmutation . ANSTO has two nuclear research reactors onsite: The High Flux Australian Reactor , or HIFAR, in operation from 1958 to 2007, and

84-533: The Open-pool Australian lightwater reactor (OPAL) designed by the Argentine company INVAP . HIFAR was permanently shut down on 30 January 2007. The OPAL reactor came online in November 2006 and the facility was officially opened on 20 April 2007. A third, smaller unit, being a 100 kW thermal Argonaut-class reactor named MOATA , was in operation between 1961 and 1995, before being decommissioned in 2009. The reactor

96-497: The earliest. In part this is because the development of reliable LEU fuel for high neutron flux research reactors, that does not fail through swelling, has been slower than expected. As of 2020 , 72 HEU research reactors remain. While in the 1950s, 1960s and 1970s there were a number of companies that specialized in the design and construction of research reactors, the activity of this market cooled down afterwards, and many companies withdrew. The market has consolidated today into

108-469: The fuel is used. On the other hand, their fuel requires more highly enriched uranium , typically up to 20% U-235 , although some use 93% U-235; while 20% enrichment is not generally considered usable in nuclear weapons, 93% is commonly referred to as " weapons-grade ". They also have a very high power density in the core, which requires special design features. Like power reactors, the core needs cooling, typically natural or forced convection with water, and

120-776: The reaction in less than a second. CROCUS has a license to produce 100 watts (0.13 hp) or a neutron flux of ~2.5 × 10 cms at the core's center. Research reactor The neutrons produced by a research reactor are used for neutron scattering , non-destructive testing, analysis and testing of materials , production of radioisotopes , research and public outreach and education. Research reactors that produce radioisotopes for medical or industrial use are sometimes called isotope reactors . Reactors that are optimised for beamline experiments nowadays compete with spallation sources . Research reactors are simpler than power reactors and operate at lower temperatures. They need far less fuel, and far less fission products build up as

132-522: The use of low enriched uranium (LEU), in support of its nonproliferation policy. By that time, the U.S. had supplied research reactors and highly enriched uranium to 41 countries as part of its Atoms for Peace program. In 2004, the U.S. Department of Energy extended its Foreign Research Reactor Spent Nuclear Fuel Acceptance program until 2019. As of 2016, a National Academies of Sciences, Engineering, and Medicine report concluded converting all research reactors to LEU cannot be completed until 2035 at

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144-451: Was awarded to INVAP that built the reactor. In recent years, AECL withdrew from this market, and Siemens and Technicatom activities were merged into Areva . A complete list can be found at the List of nuclear research reactors . Research centers that operate a reactor: Decommissioned research reactors: ANSTO The Australian Nuclear Science and Technology Organisation ( ANSTO )

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