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Encyclopedia > Nuclear reactor
Core of a small nuclear reactor used for research.
Core of a small nuclear reactor used for research.
Energy Portal

A nuclear reactor is a device in which nuclear chain reactions are initiated, controlled, and sustained at a steady rate (as opposed to a nuclear bomb, in which the chain reaction occurs in a fraction of a second and is completely uncontrolled). Image File history File links Download high resolution version (2560x1920, 798 KB) Réacteur CROCUS; expérience CAROUSEL; divers expériences et manips; détecteurs et instruments. ... Image File history File links Download high resolution version (2560x1920, 798 KB) Réacteur CROCUS; expérience CAROUSEL; divers expériences et manips; détecteurs et instruments. ... Image File history File links Portal. ... Albert Einsteins letter to President Roosevelt in 1939 about his concern, about (Nuclear chain reactions) Click for closeup of letter A nuclear chain reaction occurs when on average more than one nuclear reaction is caused by another nuclear reaction, thus leading to an exponential increase in the number of... The mushroom cloud of the atomic bombing of Nagasaki, Japan, in 1945 lifted nuclear fallout some 18 km (60,000 feet) above the epicenter. ...


Nuclear reactors are used for many purposes. The most significant current use is for the generation of electrical power (see nuclear power). Research reactors are used for radioisotope production and for beamline experiments with free neutrons. Historically, the first use of nuclear reactors was the production of weapons grade plutonium for nuclear weapons. Another military use is submarine / ship propulsion (Though this involves a much smaller nuclear reactor than the one used in a nuclear power plant). Transmission lines in Lund, Sweden Electric power, often known as power or electricity, involves the production and delivery of electrical energy in sufficient quantities to operate domestic appliances, office equipment, industrial machinery and provide sufficient energy for both domestic and commercial lighting, heating, cooking and industrial processes. ... A nuclear power station. ... Research reactors comprise a wide range of civil and commercial nuclear reactors which are generally not used for power generation. ... A radionuclide is an atom with an unstable nucleus. ... ≈≈ This article or section does not cite its references or sources. ... Weapons-grade means that a substance is pure enough to be used to make a weapon or has properties that make it suitable for weapons use. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter. ... A nuclear power station. ...


Currently all commercial nuclear reactors are based on nuclear fission, and are considered by some to be a safe and pollution-free method of generating electricity. Conversely, some consider nuclear reactors problematic for their safety, and health risks, or for the risk of nuclear proliferation. For the generation of electrical power by fission, see Nuclear power plant An induced nuclear fission event. ... World map with nuclear weapons development status represented by color. ...


Fusion power is an experimental technology based on nuclear fusion instead of fission. There are other devices in which nuclear reactions occur in a controlled fashion, including radioisotope thermoelectric generators and atomic batteries, which generate heat and power by exploiting passive radioactive decay, as well as Farnsworth-Hirsch fusors, in which controlled nuclear fusion is used to produce neutron radiation. The Sun is a natural fusion reactor. ... The deuterium-tritium (D-T) fusion reaction is considered the most promising for producing fusion power. ... // A radioisotope thermoelectric generator (RTG) is a simple electrical generator which obtains its power from radioactive decay. ... The terms atomic battery, nuclear battery and radioisotope battery are used to describe a device which uses the charged particle emissions from a radioactive isotope to directly generate electricity. ... US3386883 - fusor -- June 4, 1968 The Farnsworth-Hirsch Fusor, or simply fusor, is an apparatus designed by Philo T. Farnsworth to create nuclear fusion. ... Neutron radiation consists of free neutrons. ...

Contents

Applications

A nuclear power station. ... Electricity generation is the first process in the delivery of electricity to consumers. ... HVAC may also stand for High-voltage alternating current HVAC is an initialism that stands for heating, ventilation and air-conditioning. This is sometimes referred to as climate control. ... Hydrogen production is done in bulk today from hydrocarbon fossil fuels via a chemical path. ... Shevchenko BN350 desalination unit situated on the shore of the Caspian Sea. ... Nuclear propulsion can include a wide variety of methods, the commonality of which is the use of some form of nuclear reaction as their primary power source. ... Nuclear marine propulsion is propulsion of a Merchant ship powered by a nuclear reactor. ... In a nuclear thermal rocket a working fluid, usually hydrogen, is heated in a high temperature nuclear reactor, and then expands through a rocket nozzle to create thrust. ... An artists conception of a spacecraft powered by nuclear pulse propulsion Nuclear pulse propulsion (or External Pulsed Plasma Propulsion, as it is termed in one recent NASA document) is a proposed method of spacecraft propulsion that uses nuclear explosions for thrust. ... // Transmutation is the conversion of one object into another. ... General Name, Symbol, Number plutonium, Pu, 94 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white Atomic mass (244) g·mol−1 Electron configuration [Rn] 5f6 7s2 Electrons per shell 2, 8, 18, 32, 24, 8, 2 Physical properties Phase solid Density (near r. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 kilometers (11 mi) above the hypocenter. ... Radiation in physics is the process of emitting energy in the form of waves or particles. ... Isotopes are any of the several different forms of an element each having different atomic mass. ... General Name, Symbol, Number americium, Am, 95 Chemical series actinides Group, Period, Block n/a, 7, f Appearance silvery white Atomic mass (243) g/mol Electron configuration [Rn] 5f7 7s2 Electrons per shell 2, 8, 18, 32, 25, 8, 2 Physical properties Phase solid Density (near r. ... A smoke detector or smoke alarm is an active fire protection device, subject to stringent bounding, that detects airborne smoke and issues an audible alarm, thereby alerting nearby people to the danger of fire. ... Research is often described as an active, diligent, and systematic process of inquiry aimed at discovering, interpreting, and revising facts. ... Neutron radiation consists of free neutrons. ... Positron emission is a type of beta decay, sometimes referred to as beta plus (β+). In beta plus decay, a proton is converted to a neutron via the weak nuclear force and a beta plus particle (a positron) and a neutrino are emitted. ... // How Neutron Activation Analysis Works Neutron Activation Analysis (NAA) is a nuclear process used for determining certain concentrations of elements in a vast amount of materials. ... Potassium-argon or K-Ar dating is a geochronological method used in many geoscience disciplines. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

History

An image from the Fermi-Szilárd "neutronic reactor" patent.

Although mankind has only tamed nuclear power recently, the first nuclear reactors were naturally occurring.[1] Fifteen natural fission reactors have so far been found in three separate ore deposits at the Oklo mine in Gabon, West Africa. First discovered in 1972 by French physicist Francis Perrin, they are collectively known as the Oklo Fossil Reactors. These reactors ran for approximately 150 million years, averaging 100 kW of power output during that time. The concept of a natural nuclear reactor was theorized as early as 1956 by Paul Kuroda at the University of Arkansas [2] Image File history File links Download high resolution version (507x800, 228 KB) Figure 38 from US Patent 2,708,656, Neutronic Reactor, awarded to Enrico Fermi and Leo Szilard. ... Image File history File links Download high resolution version (507x800, 228 KB) Figure 38 from US Patent 2,708,656, Neutronic Reactor, awarded to Enrico Fermi and Leo Szilard. ... Oklo is a place in the West African state of Gabon. ...  Western Africa (UN subregion)  Maghreb[1] West Africa or Western Africa is the westernmost region of the African continent. ... Francis Perrin (Paris, 1901 - id. ... Natural Reactors refer to a handful of Uranium deposits that have been discovered, mostly in Oklo, Gabon. ... Year 1956 (MCMLVI) was a leap year starting on Sunday of the Gregorian calendar. ... The University of Arkansas known also as the U of A or UA, is a public co-educational land-grant university. ...


Enrico Fermi and Leó Szilárd, while both were at the University of Chicago, were the first to build a nuclear pile and demonstrate a controlled chain reaction on December 2, 1942. In 1955 they shared U.S. Patent 2,708,656  for the nuclear reactor. Enrico Fermi (September 29, 1901 – November 28, 1954) was an Italian physicist most noted for his work on the development of the first nuclear reactor, and for his contributions to the development of quantum theory, particle physics and statistical mechanics. ... Leó Szilárd (February 11, 1898 – May 30, 1964 Originaly Szilárd Leó) was a Hungarian-American physicist who conceived the nuclear chain reaction and worked on the Manhattan Project. ... The University of Chicago is a private university located principally in the Hyde Park neighborhood of Chicago. ... On December 2, 1942, the worlds first self-sustaining nuclear chain reaction, Chicago Pile-1, took place on a squash court beneath Stagg Field on the University of Chicago campus. ... December 2 is the 336th day (337th in leap years) of the year in the Gregorian calendar. ... Year 1942 (MCMXLII) was a common year starting on Thursday (the link is to a full 1942 calendar). ... 1955 (MCMLV) was a common year starting on Saturday of the Gregorian calendar. ...


The first nuclear reactors were used to generate plutonium for nuclear weapons. Additional reactors were used in the navy (see United States Naval reactor) to propel submarines and aircraft carriers. In the mid-1950s, both the Soviet Union and western countries were expanding their nuclear research to include non-military uses of the atom. However, as with the military program, much of the non-military work was done in secret. United States Naval reactors are given three-character designations consisting of a letter representing the ship type the reactor is designed for, a consecutive generation number, and a letter indicating the reactors designer. ... German UC-1 class World War I submarine A model of Günther Priens Unterseeboot 47 (U-47), German WWII Type VII diesel-electric hunter Typhoon class nuclear ballistic missile submarine USS Virginia, a Virginia-class nuclear attack (SSN) submarine A submarine is a specialized watercraft that can operate... Four aircraft carriers, Principe-de-Asturias, USS Wasp, USS Forrestal and HMS Invincible (front-to-back), showing the difference in size between a supercarrier, light V/STOL carriers, and an amphibious carrier. ... // Recovering from World War II and its aftermath, the economic miracle emerged in West Germany and Italy. ...


On December 20, 1951, electric power from a nuclear powered generator was produced for the first time at Experimental Breeder Reactor-I (EBR-1) located near Arco, Idaho. On June 26, 1954, at 5:30 pm, the world's first nuclear power plant to generate electricity began operations at Obninsk, Kaluga Oblast, USSR. It produced 5 megawatts (electrical), enough to power 2,000 homes. [3][4]. December 20 is the 354th day of the year (355th in leap years) in the Gregorian calendar. ... 1951 (MCMLI) was a common year starting on Monday; see its calendar. ... Experimental Breeder Reactor Number 1 in Idaho, the birthplace of atomic energy. ... Arco, Idaho Arco is a city located in Butte County, Idaho. ... June 26 is the 177th day of the year (178th in leap years) in the Gregorian Calendar, with 188 days remaining. ... Year 1954 (MCMLIV) was a common year starting on Friday of the Gregorian calendar. ... Obninsk (Russian: ) is a city in Kaluga Oblast, Russia, located 100 km south-west of Moscow, on the main rail line between Moscow and Kiev. ... Kaluga Oblast (Russian: ) (29,900 km², pop. ...

Calder Hall unit 1, the world's first commercial scale nuclear power station.
Calder Hall unit 1, the world's first commercial scale nuclear power station.

The world's first commercial scale nuclear power station, Calder Hall,in England, began generation on October 17, 1956 [5] Another early power reactor was the Shippingport Reactor in Pennsylvania (1957). Image File history File links Calderhall. ... Image File history File links Calderhall. ... The Sellafield facility on the Cumbrian coast, United Kingdom Sellafield is the name of a nuclear site, close to the village and railway station of Seascale, operated by the British Nuclear Group, but owned since 1 April 2005 by the Nuclear Decommissioning Authority. ... October 17 is the 290th day of the year (291st in leap years) in the Gregorian calendar. ... Year 1956 (MCMLVI) was a leap year starting on Sunday of the Gregorian calendar. ... The Shippingport reactor was the first full-scale nuclear power plant in the United States. ... Official language(s) English, Pennsylvania Dutch Capital Harrisburg Largest city Philadelphia Area  Ranked 33rd  - Total 46,055 sq mi (119,283 km²)  - Width 280 miles (455 km)  - Length 160 miles (255 km)  - % water 2. ...


Even before the 1979 Three Mile Island accident, new orders for nuclear plants in the U.S. had ceased for economic reasons primarily related to greatly extended construction times. As of 2004, no new nuclear plants have been ordered in the USA since 1978 [6], although that may change by 2010 (see Future of the industry below). For the song by The Smashing Pumpkins, see 1979 (song). ... Three Mile Island Nuclear Generating Station consists of two nuclear reactors, each with its own containment building and cooling towers. ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ... This article or section does not cite its references or sources. ...


Unlike the Three Mile Island accident, the 1986 Chernobyl accident did not increase regulations affecting Western reactors. This was because the Chernobyl reactors were known to be an unsafe design, using the RBMK, without containment buildings and operated unsafely, and the West had little to learn from them [7]. There was however political fallout: Italy held a referendum the next year in 1987[8], the results of which led to a shutdown of the country's four nuclear power plants. 1986 (MCMLXXXVI) was a common year starting on Wednesday of the Gregorian calendar. ... The nuclear power plant at Chernobyl prior to the completion of the sarcophagus. ... RBMK is an acronym for the Russian reaktor bolshoy moshchnosti kanalniy (Russian: Реактор Большой Мощности Канальный) which means reactor (of) high power (of the) channel (type), and describes a now obsolete class of graphite-moderated nuclear power reactor which was built only in the Soviet Union. ... A containment building, in its most common usage, is a steel or concrete structure enclosing a nuclear reactor. ... Ballots of the Argentine plebiscite of 1984 on the border treaty with Chile A referendum (plural: referendums or referenda) or plebiscite (from Latin plebiscita, originally a decree of the Concilium Plebis) is a direct vote in which an entire electorate is asked to either accept or reject a particular proposal. ...


The Chernobyl accident raised awareness about the possible geographical range of nuclear events, with contamination from Ukraine easily crossing national borders and spreading over significant parts of Europe. As a consequence an international organisation to promote safety awareness and professional development on operators in nuclear facilities was created: WANO; World Association of Nuclear Operators. The nuclear power plant at Chernobyl prior to the completion of the sarcophagus. ... World Association of Nuclear Operators. ...


In 1992 the Turkey Point Nuclear Generating Station in Florida, USA, was hit directly by Hurricane Andrew. Over $90 million of damage was done, largely to a water tank and to a smokestack of one of the fossil-fueled units on-site, but the containment buildings were undamaged [9][10]. 1992 (MCMXCII) was a leap year starting on Wednesday. ... The twin reactors at Turkey Point nuclear power station are on a 3,300 acre (13 km²) site in Homestead, Florida near Miami, Florida, in Dade County, Florida. ... Lowest pressure 922 mbar (hPa) Damage $26 billion (1992 USD) $45 billion (2005 USD) Fatalities 65 (26 direct, 39 indirect) Areas affected Bahamas; South Florida, Louisiana, and other areas of the Southern United States Part of the 1992 Atlantic hurricane season This article is about the 1992 hurricane; there was... A containment building, in its most common usage, is a steel or concrete structure enclosing a nuclear reactor. ...


The first organization to develop utilitarian nuclear power, the U.S. Navy, is the only organization worldwide with a totally clean record. This is perhaps because of the stringent demands of Admiral Hyman G. Rickover, who was the driving force behind nuclear marine propulsion. The U.S. Navy has operated more nuclear reactors than any other entity, other than the Soviet Navy, with no publicly known major incidents. Two U.S. nuclear submarines, USS Scorpion and Thresher, have been lost at sea, though for reasons not related to their reactors, and their wrecks are situated such that the risk of nuclear pollution is considered low. USN redirects here. ... Hyman G. Rickover (1955) Admiral Hyman George Rickover, U.S. Navy, (January 27, 1900 – July 8, 1986) was known as the Father of the Nuclear Navy, which as of November 2005 had produced 199 nuclear-powered submarines, and 19 nuclear-powered aircraft carriers and cruisers, though many of these U... Nuclear marine propulsion is propulsion of a Merchant ship powered by a nuclear reactor. ... The Soviet Navy (Russian: Военно-морской флот СССР, Voyenno-morskoy flot SSSR, literally Naval military forces of the USSR) was the naval arm of the Soviet armed forces. ... USS Scorpion (SSN-589) was the sixth ship of the United States Navy to be named for the scorpion, (hence the Scorpius constellation on her insignia). ... The second USS Thresher (SSN-593) was the lead ship of its class of nuclear-powered attack submarines in the United States Navy. ...


Nuclear power in electricity production

Main article: Nuclear power

Nuclear power from a reactor is typically utilized to produce electricity. The production of electricity is usually accomplished by somewhat standard methods that involve using heat from the nuclear reaction to power steam turbines. Nuclear power is attractive in that relatively small amounts of fuel are used to produce vast amounts of energy with no or much smaller production of free pollutants, such as greenhouse gas. A nuclear power station. ... A nuclear power station. ... Rituraj-rituraj 07:07, 7 January 2007 (UTC) A rotor of a modern steam turbine, used in a power plant A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into useful mechanical work. ... Top: Increasing atmospheric CO2 levels as measured in the atmosphere and ice cores. ...


Nuclear power is controversial since it produces radioactive waste and runs the risk of nuclear meltdown. Such events, though unlikely with proper precautions, are typically viewed as catastrophic and can produce far reaching detrimental effects, such as widespread radiation contamination. Modern reactor designs and the relatively low enrichment of nuclear reactor fuel make it essentially impossible for a nuclear explosion to occur (the Chernobyl accident was neither a modern reactor design nor was it a nuclear explosion). A nuclear meltdown occurs when the core of a nuclear reactor ceases to be properly controlled and cooled due to failure of control or safety systems, and fuel assemblies (containing the uranium or plutonium reactor fuel and highly radioactive fission products) inside the reactor begin to overheat and melt. ... It has been suggested that Nuclear explosive be merged into this article or section. ... The nuclear power plant at Chernobyl prior to the completion of the sarcophagus. ...


The future of the industry

As of March 1, 2007, Watts Bar 1, which came on-line in 1997, was the last U.S. commercial nuclear reactor to go on-line. This is often quoted as evidence of a successful worldwide campaign for nuclear power phase-out. However, political resistance to nuclear power has only ever been successful in parts of Europe, in New Zealand, in the Philippines, and in the United States. Even in the US and throughout Europe, investment in research and in the nuclear fuel cycle has continued, and some experts predict that electricity shortages, fossil fuel price increases and concern over greenhouse gas emissions will renew the demand for nuclear power plants. The Watts Bar nuclear power plant is located between Chattanooga, Tennessee and Knoxville, Tennessee on a 1,770 acre (7 km²) site. ... 1997 (MCMXCVII) was a common year starting on Wednesday of the Gregorian calendar. ... A nuclear power plant at Grafenrheinfeld, Germany. ... World map showing the location of Europe. ... The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages. ... This article is about energy crises in general. ... Top: Increasing atmospheric CO2 levels as measured in the atmosphere and ice cores. ...


Many countries remain active in developing nuclear power, including Japan, China and India, all actively developing both fast and thermal technology, South Korea and the United States, developing thermal technology only, and South Africa and China, developing versions of the Pebble Bed Modular Reactor (PBMR). Finland and France actively pursue nuclear programs; Finland has a new European Pressurized Reactor under construction by Areva. Japan has an active nuclear construction program with new units brought on-line in 2005. In the U.S., three consortia responded in 2004 to the U.S. Department of Energy's solicitation under the Nuclear Power 2010 Program and were awarded matching funds - the Energy Policy Act of 2005 authorized subsidies for up to six new reactors, and authorized the Department of Energy to build a reactor based on the Generation IV Very-High-Temperature Reactor concept to produce both electricity and hydrogen. As of the early 21st century, nuclear power is of particular interest to both China and India to serve their rapidly growing economies - both are developing fast breeder reactors. See also future energy development. In the energy policy of the United Kingdom it is recognized that there is a likely future energy supply shortfall, which may have to be filled by either new nuclear plant construction or maintaining existing plants beyond their programmed lifetime. Graphite Pebble for Reactor The pebble bed reactor (PBR) or pebble bed modular reactor (PBMR) is an advanced nuclear reactor design. ... European Pressurized Reactor (EPR) is a new fission nuclear reactor design, based on the pressurized water reactor or PWR. It has been designed and developed mainly by the Commissariat à lÉnergie Atomique in France and the Karlsruhe Research Center in Germany. ... AREVA (Euronext: CEI) is a France-based multinational industrial conglomerate that deals in energy, especially in nuclear power. ... The United States Department of Energy (DOE) is a Cabinet-level department of the United States government responsible for energy policy and nuclear safety. ... The Nuclear Power 2010 Program was unveiled by the U.S. Secretary of the Department of Energy on February 14, 2002 as one means towards addressing the expected need for new power plants. ... The Energy Policy Act of 2005 (Pub. ... The United States Department of Energy (DOE) is a Cabinet-level department of the United States government responsible for energy policy and nuclear safety. ... The Very High Temperature Reactor is a Generation IV reactor concept that uses a graphite-moderated reactor with a once-through uranium fuel cycle. ... This article is about the chemistry of hydrogen. ... The 21st century is the present century of the Anno Domini (common) era, in accordance with the Gregorian calendar. ... The fast breeder or fast breeder reactor (FBR) is a fast neutron reactor designed to breed fuel by producing more fissile material than it consumes. ... Future energy development faces great challenges due to an increasing world population, demands for higher standards of living, demands for less pollution and a much-discussed end to fossil fuels. ... Energy policy of the United Kingdom is a set of official publications and activities directed at the present and future production, transmission and use of various power technologies. ...


On September 22, 2005 it was announced that two sites in the U.S. had been selected to receive new power reactors (exclusive of the new power reactor scheduled for INL) - see Nuclear Power 2010 Program. September 22 is the 265th day of the year in the Gregorian calendar (266th in leap years). ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... The Idaho National Laboratory (INL) is an 890 square mile (2,300 km²) complex located in the Idaho desert between the towns of Arco and Idaho Falls. ... The Nuclear Power 2010 Program was unveiled by the U.S. Secretary of the Department of Energy on February 14, 2002 as one means towards addressing the expected need for new power plants. ...


It is possible that the first new nuclear power plant to be built in the United States since the 1970s may be installed in the remote town of Galena, Alaska. The town's City Council approved the idea, and Toshiba proposed to install its model 4S "nuclear battery" in Galena free of charge as a test. Galena, Alaskas City Council on December 14, 2004 tentatively accepted a proposal from Toshiba Corporation to build a small nuclear reactor in the village as a demonstration. ... Toshiba Corporations headquarters in Hamamatsucho, Tokyo Toshiba Corporation sales by division for year ending March, 31 2005 Toshiba Corporation ) (TYO: 6502 ) is a multinational high technology electrical and electronics manufacturing firm, headquartered in Tokyo, Japan. ... The Toshiba 4S (Super Safe, Small and Simple) is a “nuclear battery” reactor design. ...

See also: nuclear power phase-out and nuclear energy policy

A nuclear power plant at Grafenrheinfeld, Germany. ... Nuclear energy policy is national and international policy concerning some or all aspects of nuclear energy, such as mining for nuclear fuel, generating electricity by nuclear power, enriching and storing spent nuclear fuel and nuclear fuel reprocessing. ...

Types of reactors

NC State's PULSTAR Reactor is a 1 MW pool-type research reactor with 4% enriched, pin-type fuel consisting of UO2 pellets in zircaloy cladding.
NC State's PULSTAR Reactor is a 1 MW pool-type research reactor with 4% enriched, pin-type fuel consisting of UO2 pellets in zircaloy cladding.
The control room of NC State's Pulstar Nuclear Reactor.
The control room of NC State's Pulstar Nuclear Reactor.

A number of reactor technologies have been developed. Fission reactors can be divided roughly into two classes, depending on the energy of the neutrons that are used to sustain the fission chain reaction. Download high resolution version (480x640, 335 KB)Pulstar Nuclear Reactor. ... Download high resolution version (480x640, 335 KB)Pulstar Nuclear Reactor. ... North Carolina State University is a public, coeducational, extensive research university located in Raleigh, North Carolina, United States. ... Research reactors comprise a wide range of civil and commercial nuclear reactors which are generally not used for power generation. ... Zircaloy, also incorrectly called zircalloy, is a group of of high-zirconium alloys. ... Download high resolution version (439x601, 274 KB)Pulstar Nuclear Reactor. ... Download high resolution version (439x601, 274 KB)Pulstar Nuclear Reactor. ... North Carolina State University is a public, coeducational, extensive research university located in Raleigh, North Carolina, United States. ...

  • Thermal (slow) reactors use slow or thermal neutrons. These are characterized by moderating materials that slow neutrons until they approach the average kinetic energy of the surrounding particles, that is, until they are thermalized. Thermal neutrons have a far higher probability of fissioning U-235, and a lower probability of capture by U-238 than the faster neutrons that result from fission. As well as the moderator, thermal reactors have fuel (fissionable material), containments, pressure vessels, shielding, and instrumentation to monitor and control the reactor's systems. Most power reactors are of this type. The first plutonium production reactors were thermal reactors using a graphite moderator. Some thermal power reactors are more thermalised than others; Graphite (e.g. Russian reaktor bolshoy moshchnosti kanalniy RBMK reactors) and heavy water moderated plants (e.g. Canadian CANada Deuterium Uranium CANDU reactors) tend to be more thoroughly thermalised than pressurized water reactors PWRs and boiling water reactors BWRs, which use light water (normal water) as the moderator. Due to the extra thermalization, these types can use natural uranium/unenriched fuel.
    Thermal power reactors can again be divided into three types, depending on whether they use pressurised fuel channels, a large pressure vessel, or gas cooling.
    • Most commercial and naval reactors use reactor heated steam pressure vessels. Pressure vessels balance out pressure transients in the primary loops that occur when reactor power changes. Pressure vessels also have a small role as primary coolant make-up sources. Pressure vessels are almost always lined up to reactors and are only isolated from reactors during special maintenance or tests.
    • Pressurised channels are used by the RBMK and CANDU reactors. Channel-type reactors can be refuelled under load. This has advantages discussed under CANDU reactor.
    • Gas-cooled reactors are cooled by a circulating inert gas, usually helium. Nitrogen and carbon dioxide have also been used. Utilization of the heat varies, depending on the reactor. Some reactors run hot enough that the gas can directly power a gas turbine. Older designs usually run the gas through a heat exchanger to make steam for a steam turbine. The pebble bed reactor uses a gas-cooled design.

Since water serves as a moderator, it cannot be used as a coolant in a fast reactor. Most designs for fast power reactors have been cooled by liquid metal, usually molten sodium. They have also been of two types, called pool and loop reactors. A fast neutron reactor or simply a fast reactor is a category of nuclear reactor in which the fission chain reaction is sustained by fast neutrons. ... A fast neutron is a free neutron with a kinetic energy level close to 1 MeV (10 TJ/kg, hence a speed of 14,000 km/s. ... In nuclear engineering, a neutron moderator is a medium which reduces the velocity of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction. ... These pie-graphs showing the relative proportions of uranium-238 (blue) and uranium-235 (red) at different levels of enrichment. ... General Name, Symbol, Number plutonium, Pu, 94 Chemical series actinides Group, Period, Block ?, 7, f Appearance silvery white Atomic mass (244) g/mol Electron configuration [Rn] 5f6 7s2 Electrons per shell 2, 8, 18, 32, 24, 8, 2 Physical properties Phase solid Density (near r. ... A fast neutron is a free neutron with a kinetic energy level close to 1 MeV (10 TJ/kg, hence a speed of 14,000 km/s. ... Uranium-235 is an isotope of uranium that differs from the elements other common isotope, uranium-238, by its ability to cause a rapidly expanding fission chain reaction. ... This article does not cite its references or sources. ... The fast breeder or fast breeder reactor (FBR) is a fast neutron reactor designed to breed fuel by producing more fissile material than it consumes. ... Fertile may be used in the following conrtext: Fertility, a term used to describe the ability of people or animals to produce healthy offspring. ... There are two objects with this name: Unterseeboot 238 Uranium-238, the most common isotope of uranium This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... This article or section should be merged with Fissile Fissile material is composed of atoms that can undergo nuclear fission and sustain a fission chain reaction. ... Natural uranium (NU) refers to refined uranium with the same isotopic ratios as found in nature. ... Depleted uranium storage yard. ... The fast breeder or fast breeder reactor (FBR) is a type of fast neutron reactor that produces more fissile material than it consumes. ... Generation IV reactors (Gen IV) are a set of theoretical nuclear reactor designs currently being researched. ... A Liquid metal cooled nuclear reactor is nuclear reactor where the primary coolant is a liquid molten metal. ... The Gas-Cooled Fast Reactor (GFR) system is a Generation IV reactor concept that features a fast-neutron spectrum and closed fuel cycle for efficient conversion of fertile uranium and management of actinides. ... A thermal reactor is the most common category of nuclear reactor. ... This article does not cite its references or sources. ... In nuclear engineering, a neutron moderator is a medium which reduces the velocity of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction. ... Graphite (named by Abraham Gottlob Werner in 1789, from the Greek γραφειν: to draw/write, for its use in pencils) is one of the allotropes of carbon. ... RBMK is an acronym for the Russian reaktor bolshoy moshchnosti kanalniy (Russian: Реактор Большой Мощности Канальный) which means reactor (of) high power (of the) channel (type), and describes a now obsolete class of graphite-moderated nuclear power reactor which was built only in the Soviet Union. ... Heavy water reactors use heavy water as a neutron moderator. ... The CANDU reactor is a pressurized-heavy water, natural-uranium power reactor designed in the 1960s by a partnership between Atomic Energy of Canada Limited and the Hydro-Electric Power Commission of Ontario as well as several private industry participants. ... A pressurized water reactor (PWR) is a type of nuclear power reactor that uses ordinary (light) water for both coolant and for neutron moderator. ... A boiling water reactor (BWR) is a light water reactor design used in some nuclear power stations. ... Natural uranium (NU) refers to refined uranium with the same isotopic ratios as found in nature. ... A pressure vessel is a container designed to hold gases or liquids at a pressure different from the ambient pressure. ... RBMK is an acronym for the Russian reaktor bolshoy moshchnosti kanalniy (Russian: Реактор Большой Мощности Канальный) which means reactor (of) high power (of the) channel (type), and describes a now obsolete class of graphite-moderated nuclear power reactor which was built only in the Soviet Union. ... The CANDU reactor is a Pressurized Heavy Water Reactor developed initially in the late 1950s and 1960s by a partnership between Atomic Energy of Canada Limited (AECL), the Hydro-Electric Power Commission of Ontario (now known as Ontario Power Generation), Canadian General Electric (now known as GE Canada), as well... The CANDU reactor is a Pressurized Heavy Water Reactor developed initially in the late 1950s and 1960s by a partnership between Atomic Energy of Canada Limited (AECL), the Hydro-Electric Power Commission of Ontario (now known as Ontario Power Generation), Canadian General Electric (now known as GE Canada), as well... General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Atomic mass 4. ... General Name, Symbol, Number nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15, 2, p Appearance colorless gas Atomic mass 14. ... Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms. ... A heat exchanger is a device built for efficient heat transfer from one fluid to another, whether the fluids are separated by a solid wall so that they never mix, or the fluids are directly contacted. ... Graphite Pebble for Reactor The pebble bed reactor (PBR) or pebble bed modular reactor (PBMR) is an advanced nuclear reactor design. ... General Name, Symbol, Number sodium, Na, 11 Chemical series alkali metals Group, Period, Block 1, 3, s Appearance silvery white Atomic mass 22. ...


Further details on the classification of Nuclear reactors can be found at Classification of Nuclear Reactors. There are very few or no other articles that link to this one. ...


Current families of reactors

Pool-type reactors are a type of nuclear reactor that has a core immersed in an open pool of water. ... Pressurized water reactors (PWRs) (also VVER) are generation II nuclear power reactors that use water under high pressure as coolant and neutron moderator. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... The fast breeder or fast breeder reactor (FBR) is a type of fast neutron reactor that produces more fissile material than it consumes. ... A pressurised heavy water reactor is a nuclear power reactor that uses unenriched natural uranium as its fuel and heavy water as a moderator (deuterium oxide D2O). ... The CANDU reactor is a pressurized-heavy water, natural-uranium power reactor designed in the 1960s by a partnership between Atomic Energy of Canada Limited and the Hydro-Electric Power Commission of Ontario as well as several private industry participants. ... United States Naval reactors are given three-character designations consisting of a letter representing the ship type the reactor is designed for, a consecutive generation number, and a letter indicating the reactors designer. ...

Obsolete types still in service

Schematic diagram of a Magnox nuclear reactor showing gas flow. ... Schematic diagram of the Advanced Gas-cooled Reactor. ... RBMK is an acronym for the Russian reaktor bolshoy moshchnosti kanalniy (Russian: Реактор Большой Мощности Канальный) which means reactor (of) high power (of the) channel (type), and describes a now obsolete class of graphite-moderated nuclear power reactor which was built only in the Soviet Union. ...

Other types of reactors

Aqueous homogeneous reactors (AHR) are a type of nuclear reactor in which soluble nuclear salts (usually uranium sulfate or uranium nitrate) have been dissolved in water. ... A liquid-fluoride reactor (a specific example of a Molten salt reactor) is a nuclear reactor wherein the nuclear materials are fluoride salts dissolved in a solution of other fluoride salts. ...

Advanced reactors

More than a dozen advanced reactor designs are in various stages of development.[11]Some are evolutionary from the PWR, BWR and PHWR designs above, some are more radical departures. The former include the Advanced Boiling Water Reactor (ABWR), two of which are now operating with others are under construction, and the planned passively safe ESBWR and AP1000 units (see Nuclear Power 2010 Program). The best-known radical new design is the Pebble Bed Modular Reactor (PBMR), a High Temperature Gas Cooled Reactor (HTGCR). The Clean And Environmentally Safe Advanced Reactor (CAESAR) is a nuclear reactor concept that uses steam as a moderator - this design is still in development. Possible designs of subcritical reactors exist on the drawing board, notably the energy amplifier, awaiting political support and funding. Some, such as the Integral Fast Reactor (IFR), have been cancelled due to a political climate unfavorable to nuclear power. Pressurized water reactors (PWRs) (also VVER) are generation II nuclear power reactors that use water under high pressure as coolant and neutron moderator. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... A pressurised heavy water reactor is a nuclear power reactor that uses unenriched natural uranium as its fuel and heavy water as a moderator (deuterium oxide D2O). ... The Advanced Boiling Water Reactor (ABWR) is an improved design of boiling water reactor. ... Passively safe is a form of nuclear reactor which uses the laws of physics to keep the nuclear reaction under control rather than engineered safety systems. ... The Economic Simplified Boiling Water Reactor (ESBWR) is a generation III+ reactor which builds on the success of the ABWR. Both are designs by General Electric, and are based on their BWR design. ... The Nuclear Power 2010 Program was unveiled by the U.S. Secretary of the Department of Energy on February 14, 2002 as one means towards addressing the expected need for new power plants. ... Graphite Pebble for Reactor The pebble bed reactor (PBR) or pebble bed modular reactor (PBMR) is an advanced nuclear reactor design. ... The High Temperature Gas-cooled Reactor or HTGR is a gas cooled reacter that is fueled with a mixture of graphite and spherical fuel particles. ... The Clean And Environmentally Safe Advanced Reactor (CAESAR) is a nuclear reactor concept that uses steam as a moderator. ... A subcritical reactor is a nuclear fission reactor that produces fission without achieving criticality. ... In nuclear physics, an energy amplifier is a novel type of nuclear power reactor, a subcritical reactor, in which an energetic particle beam is used to stimulate a reaction, which in turn releases enough energy to power the particle accelerator and leave an energy profit for power generation. ... The Integral Fast Reactor or Advanced Liquid-Metal Reactor is a design for a nuclear fast reactor with a specialized nuclear fuel cycle. ...


Generation IV reactors

Even more-advanced reactors are also on the drawing boards. These are the Generation IV reactors[12], which are divided into seven overall design classes. Generation IV reactors (Gen IV) are a set of theoretical nuclear reactor designs currently being researched. ...

The Gas-Cooled Fast Reactor (GFR) system is a Generation IV reactor that features a fast-neutron spectrum and closed fuel cycle for efficient conversion of fertile uranium and management of actinides. ... The Lead-cooled Fast Reactor is a Generation IV reactor that features a fast-spectrum lead or lead/bismuth eutectic liquid metal-cooled reactor with a closed fuel cycle. ... A molten salt reactor is a type of nuclear reactor where the working fluid is a molten salt. ... The Sodium-cooled fast reactor is a sodium cooled reactor that uses fast neutrons. ... Supercritical water reactor scheme. ... Very high temperature reactor scheme. ... Similar to how the fission-fragment rocket produces thrust, a fission fragment reactor is a nuclear reactor that generates electricity by decelerating an ion beam of fission byproducts instead of using nuclear reactions to generate heat. ...

Nuclear fuel cycle

Main article: nuclear fuel cycle The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages. ...


Thermal reactors generally depend on refined and enriched uranium. Some nuclear reactors can operate with a mixture of plutonium and uranium (see MOX). The process by which uranium ore is mined, processed, enriched, used, possibly reprocessed and disposed of is known as the nuclear fuel cycle. These pie-graphs showing the relative proportions of uranium-238 (blue) and uranium-235 (red) at different levels of enrichment. ... The Mox are a alien race that inhabit Planet X, they are divided into clans which seem to be forever at war. ... // Nuclear reprocessing separates any usable elements (e. ... The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages. ...


Uranium is sampled and mined as other metals are, via open-pit mining or leach mining. Raw uranium ore found in the United States ranges from 0.05% to 0.3% uranium oxide. Uranium ore is not rare; the largest probable resources, extractable at a cost of US$80 per kilogram or cheaper, are located in Australia, Kazakhstan, Canada, South Africa, Brazil, Namibia, Russia, and the United States. This article is about mineral extraction. ...


The raw ore is then milled, where it is ground and chemically leached. The resulting powder of natural uranium oxide is called "yellowcake". The yellowcake powder is then converted to uranium hexafluoride to prepare for enrichment. Powdered yellowcake in a drum Yellowcakes (also known as urania) are uranium concentrates obtained from leach solutions. ... Uranium hexafluoride, or UF6, is a compound used in the uranium enrichment process that produces fuel for nuclear reactors and nuclear weapons. ...


Under 1% of the uranium found in nature is the easily fissionable U-235 isotope and as a result most reactor designs require enriched fuel. Enrichment involves increasing the percentage of U-235 and is usually done by means of gaseous diffusion or gas centrifuge. The enriched result is then converted into uranium dioxide powder, which is pressed and fired onto pellet form. These pellets are stacked into tubes which are then sealed and called fuel rods. Many of these fuel rods are used in each nuclear reactor. Isotopes are any of the several different forms of an element each having different atomic mass. ... -1... The gas centrifuge is a hyper-centrifuge used to produce enriched uranium. ... UO2 A black, radioactive, crystalline powder, once used in the late 1800s to mid-1900s in ceramic glazes. ... Nuclear fuel is any material that can be consumed to derive nuclear energy, by analogy to chemical fuel that is burned to derive energy. ...


Most BWR and PWR commercial reactors use uranium enriched to about 4% U-235, many research reactors use highly enriched, or weapons grade uranium, while some commercial reactors with a high neutron economy do not require the fuel to be enriched at all. Research reactors comprise a wide range of civil and commercial nuclear reactors which are generally not used for power generation. ... Neutron economy is defined as the ratio of an adjoint weighted average of the excess neutron production divided by an adjoint weighted average of the fission production. ...


It should be noted that fissionable U-235 and non-fissionable U-238 are both used in the fission process. U-235 is fissionable by thermal (i.e. slow-moving) neutrons. A thermal neutron is one which is moving about the same speed as the atoms around it. Since all atoms vibrate proportional to their absolute temperature, a thermal neutron has the best opportunity to fission U-235 when it is moving at this same vibrational speed. On the other hand, U-238 is more likely to capture a neutron when the neutron is moving very fast. This U-239 atom will soon decay into plutonium-239, which is another fuel. Pu-239 is a viable fuel and must be accounted for even when a highly enriched uranium fuel is used. Plutonium fissions will dominate the U-235 fissions in some reactors, especially after the initial loading of U-235 is spent. Plutonium is fissionable with both fast and thermal neutrons, which make it ideal for either nuclear reactors or nuclear bombs. Fig. ...


Most reactor designs in existence are thermal reactors and typically use water as a neutron moderator (moderator means that it slows down the neutron to a thermal speed) and as a coolant. But in a fast breeder reactor, some other kind of coolant is used which will not moderate or slow the neutrons down much. This enables fast neutrons to dominate, which can effectively be used to constantly replenish the fuel supply. By merely placing cheap unenriched uranium into such a core, the non-fissionable U-238 will be turned into Pu-239, "breeding" fuel. The fast breeder or fast breeder reactor (FBR) is a fast neutron reactor designed to breed fuel by producing more fissile material than it consumes. ...


Fueling of nuclear reactors

The amount of energy in the reservoir of nuclear fuel is frequently expressed in terms of "full-power days," which is the number of 24-hour periods (days) a reactor is scheduled for operation at full power output for the generation of heat energy. The number of full-power days in a reactor's operating cycle (between refueling outage times) is related to the amount of fissile uranium-235 (U-235) contained in the fuel assemblies at the beginning of the cycle. A higher percentage of U-235 in the core at the beginning of a cycle will permit the reactor to be run for a greater number of full-power days. Nuclear fuel is any material that can be consumed to derive nuclear energy, by analogy to chemical fuel that is burned to derive energy. ... This article or section should include material from Fissile material In nuclear engineering, a fissile material is one that is capable of sustaining a chain reaction of nuclear fission. ... Uranium-235 is an isotope of uranium that differs from the elements other common isotope, uranium-238, by its ability to cause a rapidly expanding fission chain reaction. ...


At the end of the operating cycle, the fuel in some of the assemblies is "spent," and is discharged and replaced with new (fresh) fuel assemblies. Although in practice, it is the buildup of reaction poisons in nuclear fuel that determines the lifetime of nuclear fuel in a reactor; long before all possible fissions have taken place, the buildup of long-lived neutron absorbing fission products damps out the chain reaction. The fraction of the reactor's fuel core replaced during refueling is typically one-fourth for a boiling-water reactor and one-third for a pressurized-water reactor. For information on radioactive toxins see Radiation poisoning A nuclear poison is a substances with a large neutron absorption cross-section in applications, such as nuclear reactors, when absorbing neutrons is an undesirable effect. ...


Not all reactors need to be shut down for refueling; for example, pebble bed reactors, RBMK reactors, molten salt reactors, Magnox, AGR and CANDU reactors allow fuel to be shifted through the reactor while it is running. In a CANDU reactor, this also allows individual fuel elements to be moved about within the reactor core to places that are best suited to the amount of U-235 in the fuel element. Graphite Pebble for Reactor The pebble bed reactor (PBR) or pebble bed modular reactor (PBMR) is an advanced nuclear reactor design. ... RBMK is an acronym for the Russian reaktor bolshoy moshchnosti kanalniy (Russian: Реактор Большой Мощности Канальный) which means reactor (of) high power (of the) channel (type), and describes a now obsolete class of graphite-moderated nuclear power reactor which was built only in the Soviet Union. ... A molten salt reactor is a type of nuclear reactor where the working fluid is a molten salt. ... Schematic diagram of a Magnox nuclear reactor showing gas flow. ... Schematic diagram of the Advanced Gas-cooled Reactor. ... The CANDU reactor is a pressurized-heavy water, natural-uranium power reactor designed in the 1960s by a partnership between Atomic Energy of Canada Limited and the Hydro-Electric Power Commission of Ontario as well as several private industry participants. ...


The amount of energy extracted from nuclear fuel is called its "burn up," which is expressed in terms of the heat energy produced per initial unit of fuel weight. Burn up is commonly expressed as megawatt days thermal per metric ton of initial heavy metal.


Waste management

The final stage of the nuclear fuel cycle is the management of the still highly radioactive, "spent" fuel, which constitutes the most problematic component of the nuclear waste stream. After fifty years of nuclear power the question of how to deal with this material remains fraught with safety concerns and technical problems, and one of the most important lines of criticism of the industry is based on the long-term risks and costs associated with dealing with the waste. Political Punk band from Victorville, Ca WWW.MYSPACE.COM/NUCLEARWASTEX ...


Management of the spent fuel can include various combinations of storage, reprocessing, and disposal. In practice storage has been the primary modality so far. Typically the spent fuel rods are stored in a pool of water which is usually located on-site. The water provides both cooling for the still-decaying uranium, and shielding from the continuing radioactivity. After a few decades some on-site storage involves moving the now cooler, less radioactive fuel to a dry-storage facility, where the fuel is stored in steel and concrete containers which are monitored carefully.


Another, more permanent method of disposal of high-level nuclear waste calls for the material to be buried deep underground in certain geological formations. The Canadian government, for example, is seriously considering this method of disposal, known as the Deep Geological Disposal concept. Under the current plan, a vault is to be dug 500 to 1000 meters below ground, under the Canadian Shield, one of the most stable landforms on the planet. The vaults are to be dug inside geological formations known as batholiths, formed about a billion years ago. The used fuel bundles will be encased in a corrosion-resistant container, and further surrounded by a layer of buffer material, possibly of a special kind of clay (bentonite clay). The case itself is designed to last for thousands of years, while the clay would further slow the corrosion rates of the container. The batholiths themselves are chosen for their low ground-water movement rates, geological stability, and low economic value[13]. Canadian Shield The Canadian Shield— also called the Precambrian Shield, Laurentian Shield, Bouclier Canadien (French), or Laurentian Plateau— is a large shield covered by a thin layer of soil that forms the nucleus of the North American craton. ... Half Dome A batholith is a large emplacement of igneous intrusive (also called plutonic) rock that forms from cooled magma deep in the Earths crust. ... It has been suggested that Pascalite be merged into this article or section. ...


The Finnish government has already started building a vault to store nuclear waste 500 to 1000 meters below ground, not far from the nuclear plant at Olkiluoto. The Olkiluoto island with two existing and one planned nuclear power plant Olkiluoto is an island located in western Finland in the municipality of Eurajoki. ...


Storing high level nuclear waste above ground for a century or so is considered appropriate by many scientists. This allows for the material to be more easily observed and any problems detected and managed, while the decay over this time period significantly reduces the level of radioactivity and the associated harmful effects to the container material. It is also considered likely that over the next century newer materials will be developed which will not break down as quickly when exposed to a high neutron flux thus increasing the longevity of the container once it is permanently buried.


Reprocessing is attractive in principle because (1) it can recycle nuclear fuel and (2) it can prepare the waste material for disposal. Considerable experience with reprocessing in France however, has indicated that a one way fuel cycle based on extracting and processing fresh supplies of uranium and storing the spent fuel is more economical than reprocessing, not the least because in the process of plutonium extraction, the volume of high-level liquid radioactive waste increases about 17-fold. // Nuclear reprocessing separates any usable elements (e. ...


Natural nuclear reactors

A natural nuclear fission reactor can occur under certain circumstances that mimic the conditions in a constructed reactor. The only known natural nuclear reactors formed 2 billion years ago in Oklo, Gabon, Africa. [14] Such reactors can no longer form on Earth: radioactive decay over this immense time span has reduced the proportion of U-235 in naturally occurring uranium to below the amount required to sustain a chain reaction. Natural Reactors refer to a handful of Uranium deposits that have been discovered, mostly in Oklo, Gabon. ... Oklo is a place in the West African state of Gabon. ...


The natural nuclear reactors formed when a uranium-rich mineral deposit became inundated with groundwater that acted as a neutron moderator, and a strong chain reaction took place. The water moderator would boil away as the reaction increased, slowing it back down again and preventing a meltdown. The fission reaction was sustained for hundreds of thousands of years.


These natural reactors are extensively studied by scientists interested in geologic radioactive waste disposal. They offer a case study of how radioactive isotopes migrate through the earth's crust. This is a significant area of controversy as opponents of geologic waste disposal fear that isotopes from stored waste could end up in water supplies or be carried into the environment.


See also

Electricity generation is the first process in the delivery of electricity to consumers. ... In nuclear physics, an energy amplifier is a novel type of nuclear power reactor, a subcritical reactor, in which an energetic particle beam is used to stimulate a reaction, which in turn releases enough energy to power the particle accelerator and leave an energy profit for power generation. ... Enrico Fermi (September 29, 1901 – November 28, 1954) was an Italian physicist most noted for his work on the development of the first nuclear reactor, and for his contributions to the development of quantum theory, particle physics and statistical mechanics. ... Future energy development faces great challenges due to an increasing world population, demands for higher standards of living, demands for less pollution and a much-discussed end to fossil fuels. ... Green Field status is a term used to describe an end point wherein a parcel of land that had been in industrial use is, in principle, restored to the conditions existing before the construction of the plant. ... Pathways from airborne radioactive contamination to man This article covers notable accidents involving nuclear material. ... List of nuclear reactors is a comprehensive annotated list of all the nuclear reactors of the world, sorted by country. ... List of United States Naval reactors is a comprehensive annotated list of all naval reactors designed, built, or used by the United States Navy. ... The Manhattan Project resulted in the development of the first nuclear weapons, and the first-ever nuclear detonation, at the Trinity test of July 16, 1945. ... Nuclear marine propulsion is propulsion of a Merchant ship powered by a nuclear reactor. ... A nuclear meltdown occurs when the core of a nuclear reactor ceases to be properly controlled and cooled due to failure of control or safety systems, and fuel assemblies (containing the uranium or plutonium reactor fuel and highly radioactive fission products) inside the reactor begin to overheat and melt. ... Nuclear physics is the branch of physics concerned with the nucleus of the atom. ... The Nuclear Reactor Operator Badge is a decoration of the United States Army which was issued between the years of 1965 and 1990. ... Most nuclear reactors use a chain reaction to induce a controlled rate of nuclear fission in fissile material, releasing both energy and free neutrons. ... Graphite Pebble for Reactor The pebble bed reactor (PBR) or pebble bed modular reactor (PBMR) is an advanced nuclear reactor design. ... A power station (also power plant) is a facility for the generation of electric power. ... A SCRAM is an emergency shutdown of a nuclear reactor - though the term has been extended to cover shutdowns of other complex operations, such as server farms and even large model railroads (see Tech Model Railroad Club). ... A possible design for SSTAR. SSTAR is an acronym for the small, sealed, transportable, autonomous reactor - being primarily researched and developed in the US by Lawrence Livermore National Laboratory. ... Aerial view of the lab and surrounding area. ... Technology assessment (TA, German Technikfolgenabschätzung) is the study and evaluation of new technologies. ... United States Naval reactors are given three-character designations consisting of a letter representing the ship type the reactor is designed for, a consecutive generation number, and a letter indicating the reactors designer. ...

References

  1. ^ Video of physics lecture - at Google Video; a natural nuclear reactor is mentioned at 42:40 mins into the video
  2. ^ Oklo: Natural Nuclear Reactors. Office of Civilian Radioactive Waste Management. Retrieved on June 28, 2006.
  3. ^ From Obninsk Beyond: Nuclear Power Conference Looks to Future. International Atomic Energy Agency. Retrieved on June 27, 2006.
  4. ^ Nuclear Power in Russia. World Nuclear Association. Retrieved on June 27, 2006.
  5. ^ 1956:Queen switches on nuclear power. BBC news. Retrieved on June 28, 2006.
  6. ^ The Rise and Fall of Nuclear Power. Public Broadcasting Service. Retrieved on June 28, 2006.
  7. ^ Backgrounder on Chernobyl Nuclear Power Plant Accident. Nuclear Regulatory Commission. Retrieved on June 28, 2006.
  8. ^ Nuclear energy: the majority of Italians remain sceptical but one out of three says yes. Observa. Retrieved on June 28, 2006.
  9. ^ EFFECT OF HURRICANE ANDREW ON TURKEY POINT NUCLEAR GENERATING STATION AND LESSONS LEARNED. Nuclear Regulatory Commission. Retrieved on June 28, 2006.
  10. ^ SUPPLEMENT 1:EFFECT OF HURRICANE ANDREW ON TURKEY POINT NUCLEAR GENERATING STATION AND LESSONS LEARNED. Nuclear Regulatory Commission. Retrieved on June 28, 2006.
  11. ^ Advanced Nuclear Power Reactors. Uranium Information Centre. Retrieved on June 28, 2006.
  12. ^ Generation IV Nuclear Reactors. Uranium Information Centre. Retrieved on June 28, 2006.
  13. ^ How is high-level nuclear waste managed in Canada?. The Canadian Nuclear FAQ. Retrieved on June 28, 2006.
  14. ^ Oklo's Natural Fission Reactors. American Nuclear Society. Retrieved on June 28, 2006.

June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... The IAEA flag The International Atomic Energy Agency (IAEA) was established as an autonomous organization on July 29, 1957. ... June 27 is the 178th day of the year (179th in leap years) in the Gregorian calendar, with 187 days remaining. ... For the Manfred Mann album, see 2006 (album). ... The World Nuclear Association (formerly the Uranium Institute) is a pro-nuclear power organisation which monitors and promotes the use of nuclear power. ... June 27 is the 178th day of the year (179th in leap years) in the Gregorian calendar, with 187 days remaining. ... For the Manfred Mann album, see 2006 (album). ... The current BBC News logo BBC News and Current Affairs is a major arm of the BBC responsible for the corporations newsgathering and production of news programmes on BBC television, radio and online. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... The Public Broadcasting Service (PBS) is a non-profit public broadcasting television service with 349 member TV stations in the United States, with some member stations available by cable in Canada. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... NRC headquarters in Rockville, MD. Nuclear Regulatory Commission (or NRC) is a United States government agency that was established by the Energy Reorganization Act in 1974, and was first opened January 19, 1975. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... NRC headquarters in Rockville, MD. Nuclear Regulatory Commission (or NRC) is a United States government agency that was established by the Energy Reorganization Act in 1974, and was first opened January 19, 1975. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... NRC headquarters in Rockville, MD. Nuclear Regulatory Commission (or NRC) is a United States government agency that was established by the Energy Reorganization Act in 1974, and was first opened January 19, 1975. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... The Uranium Information Centre is an Australian website established by companies involved in uranium mining. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... The Uranium Information Centre is an Australian website established by companies involved in uranium mining. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ... The American Nuclear Society is a non-profit, educational organization established by a group of individuals who recognized the need to bring together professional activities within the fields of nuclear science and technology. ... June 28 is the 179th day of the year (180th in leap years) in the Gregorian Calendar, with 186 days remaining. ... For the Manfred Mann album, see 2006 (album). ...

External links


  Results from FactBites:
 
Nuclear reactor - Wikipedia, the free encyclopedia (3398 words)
A nuclear reactor is a device in which nuclear chain reactions are initiated, controlled, and sustained at a steady rate (as opposed to a nuclear explosion, where the chain reaction occurs in a split second).
The concept of a natural nuclear reactor was theorized as early as 1956 by Paul Kuroda at the University of Arkansas [1].
The fraction of the reactor's fuel core replaced during refueling is typically one-fourth for a boiling-water reactor and one-third for a pressurized-water reactor.
nuclear reactor. The Columbia Encyclopedia, Sixth Edition. 2001-05 (923 words)
A nuclear reactor is sometimes called an atomic pile because a reactor using graphite as a moderator consists of a pile of graphite blocks with rods of uranium fuel inserted into it.
Reactors in which the uranium rods are immersed in a bath of heavy water are often referred to as “swimming-pool” reactors.
In a fusion reactor, the principal problem is the containment of the plasma fuel, which must be at a temperature of millions of degrees in order to initiate the reaction.
  More results at FactBites »

 
 

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