Portal:Nuclear technology

The Nuclear Technology Portal

Introduction

This symbol of radioactivity is internationally recognized.

• Nuclear technology is technology that involves the nuclear reactions of atomic nuclei. Among the notable nuclear technologies are nuclear reactors, nuclear medicine and nuclear weapons. It is also used, among other things, in smoke detectors and gun sights. (Full article...)
  
• Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants. Nuclear decay processes are used in niche applications such as radioisotope thermoelectric generators in some space probes such as Voyager 2. Reactors producing controlled fusion power have been operated since 1958 but have yet to generate net power and are not expected to be commercially available in the near future. (Full article...)
  
• A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or a combination of fission and fusion reactions (thermonuclear bomb), producing a nuclear explosion. Both bomb types release large quantities of energy from relatively small amounts of matter. (Full article...)

General images -

The following are images from various nuclear technology-related articles on Wikipedia.

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  The Calder Hall nuclear power station in the United Kingdom, the world's first commercial nuclear power station. (from Nuclear power)
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  Animation of a Coulomb explosion in the case of a cluster of positively charged nuclei, akin to a cluster of fission fragments. Hue level of color is proportional to (larger) nuclei charge. Electrons (smaller) on this time-scale are seen only stroboscopically and the hue level is their kinetic energy. (from Nuclear fission)
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  The status of nuclear power globally (click for legend) (from Nuclear power)
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  United States and USSR/Russian nuclear weapons stockpiles, 1945–2006. The Megatons to Megawatts Program was the main driving force behind the sharp reduction in the quantity of nuclear weapons worldwide since the cold war ended. (from Nuclear power)
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  An assortment of American nuclear intercontinental ballistic missiles at the National Museum of the United States Air Force. Clockwise from top left: PGM-17 Thor, LGM-25C Titan II, HGM-25A Titan I, Thor-Agena, LGM-30G Minuteman III, LGM-118 Peacekeeper, LGM-30A/B/F Minuteman I or II, PGM-19 Jupiter (from Nuclear weapon)
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  Most waste packaging, small-scale experimental fuel recycling chemistry and radiopharmaceutical refinement is conducted within remote-handled hot cells. (from Nuclear power)
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  A Minuteman III ICBM test launch from Vandenberg Air Force Base, United States. MIRVed land-based ICBMs are considered destabilizing because they tend to put a premium on striking first. (from Nuclear weapon)
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  Anti-nuclear protest near nuclear waste disposal centre at Gorleben in northern Germany (from Nuclear power)
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  Anti-nuclear weapons protest march in Oxford, 1980 (from Nuclear weapon)
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  The first nuclear weapons were gravity bombs, such as this "Fat Man" weapon dropped on Nagasaki, Japan. They were large and could only be delivered by heavy bomber aircraft (from Nuclear weapon)
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  The multi-mission radioisotope thermoelectric generator (MMRTG), used in several space missions such as the Curiosity Mars rover (from Nuclear power)
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  Following the 2011 Fukushima Daiichi nuclear disaster, the world's worst nuclear accident since 1986, 50,000 households were displaced after radiation leaked into the air, soil and sea. Radiation checks led to bans of some shipments of vegetables and fish. (from Nuclear power)
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  Ukrainian workers use equipment provided by the US Defense Threat Reduction Agency to dismantle a Soviet-era missile silo. After the end of the Cold War, Ukraine and the other non-Russian, post-Soviet republics relinquished Soviet nuclear stockpiles to Russia. (from Nuclear weapon)
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  Soviet OTR-21 Tochka missile. Capable of firing a 100-kiloton nuclear warhead a distance of 185 km (from Nuclear weapon)
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  The now decommissioned United States' Peacekeeper missile was an ICBM developed to replace the Minuteman missile in the late 1980s. Each missile, like the heavier lift Russian SS-18 Satan, could contain up to ten nuclear warheads (shown in red), each of which could be aimed at a different target. A factor in the development of MIRVs was to make complete missile defense difficult for an enemy country. (from Nuclear weapon)
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  A schematic nuclear fission chain reaction. 1. A uranium-235 atom absorbs a neutron and fissions into two new atoms (fission fragments), releasing three new neutrons and some binding energy. 2. One of those neutrons is absorbed by an atom of uranium-238 and does not continue the reaction. Another neutron is simply lost and does not collide with anything, also not continuing the reaction. However, the one neutron does collide with an atom of uranium-235, which then fissions and releases two neutrons and some binding energy. 3. Both of those neutrons collide with uranium-235 atoms, each of which fissions and releases between one and three neutrons, which can then continue the reaction. (from Nuclear fission)
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  Demonstration against nuclear testing in Lyon, France, in the 1980s (from Nuclear weapon)
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  A photograph of Sumiteru Taniguchi's back injuries taken in January 1946 by a US Marine photographer (from Nuclear weapon)
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  The launching ceremony of the USS Nautilus January 1954. In 1958 it would become the first vessel to reach the North Pole. (from Nuclear power)
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  Ballistic missile submarines have been of great strategic importance for the United States, Russia, and other nuclear powers since they entered service in the Cold War, as they can hide from reconnaissance satellites and fire their nuclear weapons with virtual impunity. (from Nuclear weapon)
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  Induced fission reaction. A neutron is absorbed by a uranium-235 nucleus, turning it briefly into an excited uranium-236 nucleus, with the excitation energy provided by the kinetic energy of the neutron plus the forces that bind the neutron. The uranium-236, in turn, splits into fast-moving lighter elements (fission products) and releases several free neutrons, one or more "prompt gamma rays" (not shown) and a (proportionally) large amount of kinetic energy. (from Nuclear fission)
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  Reactor decay heat as a fraction of full power after the reactor shutdown, using two different correlations. To remove the decay heat, reactors need cooling after the shutdown of the fission reactions. A loss of the ability to remove decay heat caused the Fukushima accident. (from Nuclear power)
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  Olkiluoto 3 under construction in 2009. It was the first EPR, a modernized PWR design, to start construction. (from Nuclear power)
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  An example of an induced nuclear fission event. A neutron is absorbed by the nucleus of a uranium-235 atom, which in turn splits into fast-moving lighter elements (fission products) and free neutrons. Though both reactors and nuclear weapons rely on nuclear chain reactions, the rate of reactions in a reactor is much slower than in a bomb. (from Nuclear reactor)
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  The two basic fission weapon designs (from Nuclear weapon)
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  The Trinity test of the Manhattan Project was the first detonation of a nuclear weapon, which led J. Robert Oppenheimer to recall verses from the Hindu scripture Bhagavad Gita: "If the radiance of a thousand suns were to burst at once into the sky, that would be like the splendor of the mighty one "... "I am become Death, the destroyer of worlds". (from Nuclear weapon)
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  The nuclear fission display at the Deutsches Museum in Munich. The table and instruments are originals, but would not have been together in the same room. (from Nuclear fission)
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  The guided-missile cruiser USS Monterey (CG 61) receives fuel at sea (FAS) from the Nimitz-class aircraft carrier USS George Washington (CVN 73). (from Nuclear power)
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  Treatment of the interior part of a VVER-1000 reactor frame at Atommash (from Nuclear reactor)
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  The Ignalina Nuclear Power Plant – a RBMK type (closed 2009) (from Nuclear reactor)
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  The Chicago Pile, the first artificial nuclear reactor, built in secrecy at the University of Chicago in 1942 during World War II as part of the US's Manhattan project (from Nuclear reactor)
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  Activity of spent UOx fuel in comparison to the activity of natural uranium ore over time (from Nuclear power)
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  Proportions of the isotopes uranium-238 (blue) and uranium-235 (red) found in natural uranium and in enriched uranium for different applications. Light water reactors use 3–5% enriched uranium, while CANDU reactors work with natural uranium. (from Nuclear power)
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  Three of the reactors at Fukushima I overheated, causing the coolant water to dissociate and led to the hydrogen explosions. This along with fuel meltdowns released large amounts of radioactive material into the air. (from Nuclear reactor)
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  Life-cycle greenhouse gas emissions of electricity supply technologies, median values calculated by IPCC (from Nuclear power)
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  The nuclear fuel cycle begins when uranium is mined, enriched, and manufactured into nuclear fuel (1), which is delivered to a nuclear power plant. After use, the spent fuel is delivered to a reprocessing plant (2) or to a final repository (3). In nuclear reprocessing, 95% of spent fuel can potentially be recycled to be returned to use in a power plant (4). (from Nuclear power)
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  This view of downtown Las Vegas shows a mushroom cloud in the background. Scenes such as this were typical during the 1950s. From 1951 to 1962 the government conducted 100 atmospheric tests at the nearby Nevada Test Site. (from Nuclear weapon)
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  A demilitarized, commercial launch of the Russian Strategic Rocket Forces R-36 ICBM; also known by the NATO reporting name: SS-18 Satan. Upon its first fielding in the late 1960s, the SS-18 remains the single highest throw weight missile delivery system ever built. (from Nuclear weapon)
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  The mushroom cloud of the atomic bomb dropped on Nagasaki, Japan, on 9 August 1945 rose over 12 kilometres (7.5 mi) above the bomb's hypocenter. An estimated 39,000 people were killed by the atomic bomb, of whom 23,145–28,113 were Japanese factory workers, 2,000 were Korean slave laborers, and 150 were Japanese combatants. (from Nuclear fission)
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  Nuclear waste flasks generated by the United States during the Cold War are stored underground at the Waste Isolation Pilot Plant (WIPP) in New Mexico. The facility is seen as a potential demonstration for storing spent fuel from civilian reactors. (from Nuclear power)
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  A visual representation of an induced nuclear fission event where a slow-moving neutron is absorbed by the nucleus of a uranium-235 atom, which fissions into two fast-moving lighter elements (fission products) and additional neutrons. Most of the energy released is in the form of the kinetic velocities of the fission products and the neutrons. (from Nuclear fission)
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  The first light bulbs ever lit by electricity generated by nuclear power at EBR-1 at Argonne National Laboratory-West, December 20, 1951. (from Nuclear power)
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  The Torness nuclear power station – an AGR (from Nuclear reactor)
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  The CANDU Qinshan Nuclear Power Plant (from Nuclear reactor)
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  Primary coolant system showing reactor pressure vessel (red), steam generators (purple), pressurizer (blue), and pumps (green) in the three coolant loop Hualong One pressurized water reactor design (from Nuclear reactor)
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  Schematic of the ITER tokamak under construction in France (from Nuclear power)
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  Fission product yields by mass for thermal neutron fission of uranium-235, plutonium-239, a combination of the two typical of current nuclear power reactors, and uranium-233, used in the thorium cycle (from Nuclear fission)
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  The Superphénix, closed in 1998, was one of the few FBRs. (from Nuclear reactor)
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  The stages of binary fission in a liquid drop model. Energy input deforms the nucleus into a fat "cigar" shape, then a "peanut" shape, followed by binary fission as the two lobes exceed the short-range nuclear force attraction distance, and are then pushed apart and away by their electrical charge. In the liquid drop model, the two fission fragments are predicted to be the same size. The nuclear shell model allows for them to differ in size, as usually experimentally observed. (from Nuclear fission)
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  Growth of worldwide nuclear power generation (from Nuclear power)
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  The Ikata Nuclear Power Plant, a pressurized water reactor that cools by using a secondary coolant heat exchanger with a large body of water, an alternative cooling approach to large cooling towers (from Nuclear power)
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  The town of Pripyat abandoned since 1986, with the Chernobyl plant and the Chernobyl New Safe Confinement arch in the distance (from Nuclear power)
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  Otto Hahn and Lise Meitner in 1912 (from Nuclear fission)
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  Drawing of the first artificial reactor, Chicago Pile-1 (from Nuclear fission)
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  J. Robert Oppenheimer, principal leader of the Manhattan Project, often referred to as the "father of the atomic bomb". (from Nuclear weapon)
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  A comparison of prices over time for energy from nuclear fission and from other sources. Over the presented time, thousands of wind turbines and similar were built on assembly lines in mass production resulting in an economy of scale. While nuclear remains bespoke, many first of their kind facilities added in the timeframe indicated and none are in serial production.Our World in Data notes that this cost is the global average, while the 2 projects that drove nuclear pricing upwards were in the US. The organization recognises that the median cost of the most exported and produced nuclear energy facility in the 2010s the South Korean APR1400, remained "constant", including in export.
  LCOE is a measure of the average net present cost of electricity generation for a generating plant over its lifetime. As a metric, it remains controversial as the lifespan of units are not independent but manufacturer projections, not a demonstrated longevity. (from Nuclear power)
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  In thermal nuclear reactors (LWRs in specific), the coolant acts as a moderator that must slow the neutrons before they can be efficiently absorbed by the fuel. (from Nuclear reactor)
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  UN vote on adoption of the Treaty on the Prohibition of Nuclear Weapons on July 7, 2017
  

    Yes

    No

    Did not vote

  (from Nuclear weapon)
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  The number of nuclear warheads by country in 2024, based on an estimation by the Federation of American Scientists. (from Nuclear weapon)
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  Share of electricity production from nuclear, 2023 (from Nuclear power)
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  The USSR and United States nuclear weapon stockpiles throughout the Cold War until 2015, with a precipitous drop in total numbers following the end of the Cold War in 1991. (from Nuclear weapon)
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  The International Atomic Energy Agency was created in 1957 to encourage peaceful development of nuclear technology while providing international safeguards against nuclear proliferation. (from Nuclear weapon)
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  Protest in Bonn against the nuclear arms race between the US/NATO and the Warsaw Pact, 1981 (from Nuclear weapon)
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  The "curve of binding energy": A graph of binding energy per nucleon of common isotopes. (from Nuclear fission)
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  Nuclear fuel assemblies being inspected before entering a pressurized water reactor in the United States (from Nuclear power)
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  The basics of the Teller–Ulam design for a hydrogen bomb: a fission bomb uses radiation to compress and heat a separate section of fusion fuel. (from Nuclear weapon)
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  The cooling towers of the Philippsburg Nuclear Power Plant in Germany (from Nuclear fission)
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  The Magnox Sizewell A nuclear power station (from Nuclear reactor)
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  Diablo Canyon – a PWR (from Nuclear reactor)
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  Mushroom cloud from the explosion of Castle Bravo, the largest nuclear weapon detonated by the US, in 1954 (from Nuclear weapon)
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  Typical composition of uranium dioxide fuel before and after approximately three years in the once-through nuclear fuel cycle of a LWR (from Nuclear power)
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  Death rates per unit of electricity production for different energy sources (from Nuclear power)
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  Edward Teller, often referred to as the "father of the hydrogen bomb" (from Nuclear weapon)
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  Lise Meitner and Otto Hahn in their laboratory (from Nuclear reactor)
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  The Leibstadt Nuclear Power Plant in Switzerland (from Nuclear power)
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  Dry cask storage vessels storing spent nuclear fuel assemblies (from Nuclear power)
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  Some of the Chicago Pile Team, including Enrico Fermi and Leó Szilárd (from Nuclear reactor)
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  Over 2,000 nuclear explosions have been conducted in over a dozen different sites around the world. Red Russia/Soviet Union, blue France, light blue United States, violet Britain, yellow China, orange India, brown Pakistan, green North Korea and light green (territories exposed to nuclear bombs). The black dot indicates the location of the Vela incident. (from Nuclear weapon)
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  Montage of an inert test of a United States Trident SLBM (submarine launched ballistic missile), from submerged to the terminal, or re-entry phase, of the multiple independently targetable reentry vehicles (from Nuclear weapon)
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  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. (from Nuclear reactor)
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  Scaled-down model of TOPAZ nuclear reactor (from Nuclear reactor)

Selected article -

Chicago Pile-1 (CP-1) was the world's first artificial nuclear reactor. On 2 December 1942, the first human-made self-sustaining nuclear chain reaction was initiated in CP-1 during an experiment led by Enrico Fermi. The secret development of the reactor was the first major technical achievement for the Manhattan Project, the Allied effort to create nuclear weapons during World War II. Developed by the Metallurgical Laboratory at the University of Chicago, CP-1 was built under the west viewing stands of the original Stagg Field. Although the project's civilian and military leaders had misgivings about the possibility of a disastrous runaway reaction, they trusted Fermi's safety calculations and decided they could carry out the experiment in a densely populated area. Fermi described the reactor as "a crude pile of black bricks and wooden timbers".

After a series of attempts, the successful reactor was assembled in November 1942 by a team of about 30 that, in addition to Fermi, included scientists Leo Szilard (who had previously formulated an idea for non-fission chain reaction), Leona Woods, Herbert L. Anderson, Walter Zinn, Martin D. Whitaker, and George Weil. The reactor used natural uranium. This required a very large amount of material in order to reach criticality, along with graphite used as a neutron moderator. The reactor contained 45,000 ultra-pure graphite blocks weighing 360 short tons (330 tonnes) and was fueled by 5.4 short tons (4.9 tonnes) of uranium metal and 45 short tons (41 tonnes) of uranium oxide. Unlike most subsequent nuclear reactors, it had no radiation shielding or cooling system as it operated at very low power – about one-half watt.

The pursuit of a reactor had been touched off by concern that Nazi Germany had a substantial scientific lead. The success of Chicago Pile-1 in producing the chain reaction provided the first vivid demonstration of the feasibility of the military use of nuclear energy by the Allies, as well as the reality of the danger that Nazi Germany could succeed in producing nuclear weapons. Previously, estimates of critical masses had been crude calculations, leading to order-of-magnitude uncertainties about the size of a hypothetical bomb. The successful use of graphite as a moderator paved the way for progress in the Allied effort, whereas the German program languished partly because of the belief that scarce and expensive heavy water would have to be used for that purpose. The Germans had failed to account for the importance of boron and cadmium impurities in the graphite samples on which they ran their test of its usability as a moderator, while Leo Szilard and Enrico Fermi had asked suppliers about the most common contaminations of graphite after a first failed test. They consequently ensured that the next test would be run with graphite entirely devoid of them. As it turned out, both boron and cadmium were strong neutron poisons.

In 1943, CP-1 was moved to Site A, a wartime research facility near Chicago, where it was reconfigured to become Chicago Pile-2 (CP-2). There, it was operated for research until 1954, when it was dismantled and buried. The stands at Stagg Field were demolished in August 1957 and a memorial quadrangle now marks the experiment site's location, which is now a National Historic Landmark and a Chicago Landmark. (Full article...)

More selected articles

Selected picture -

Credit: US Army Corps of Engineers

"100-B REACTOR AND WATER TREATMENT AREA." B Reactor is at center.

Did you know?

• ... that the area of Cultybraggan Camp has been a royal hunting ground, a prison for fervent Nazis and the site of an underground bunker intended for use in a nuclear war?
• ... that Jeya Wilson invited New Zealand prime minister David Lange to debate the moral indefensibility of nuclear weapons at the Oxford Union?
• ... that the Russian and Belarussian military exercise Zapad 2009 involved nuclear-capable ballistic missiles?
• ... that campaigning by climate activist Kimiko Hirata halted plans to build 17 new coal-fired power plants following the Fukushima nuclear disaster in Japan?
• ... that Project Carryall proposed the detonation of 23 nuclear devices in California to build a road?
• ... that the British National Hospital Service Reserve trained volunteers to carry out first aid in the aftermath of a nuclear or chemical attack?

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• WikiProject Energy
• WikiProject Technology
• WikiProject Military history

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Selected biography -

Harold Clayton Urey ForMemRS (/ˈjʊəri/ YOOR-ee; April 29, 1893 – January 5, 1981) was an American physical chemist whose pioneering work on isotopes earned him the Nobel Prize in Chemistry in 1934 for the discovery of deuterium. He played a significant role in the development of the atom bomb, as well as contributing to theories on the development of organic life from non-living matter.

Born in Walkerton, Indiana, Urey studied thermodynamics under Gilbert N. Lewis at the University of California, Berkeley. After he received his PhD in 1923, he was awarded a fellowship by the American-Scandinavian Foundation to study at the Niels Bohr Institute in Copenhagen. He was a research associate at Johns Hopkins University before becoming an associate professor of chemistry at Columbia University. In 1931, he began work with the separation of isotopes that resulted in the discovery of deuterium.

During World War II, Urey turned his knowledge of isotope separation to the problem of uranium enrichment. He headed the group located at Columbia University that developed isotope separation using gaseous diffusion. The method was successfully developed, becoming the sole method used in the early post-war period. After the war, Urey became professor of chemistry at the Institute for Nuclear Studies, and later Ryerson professor of chemistry at the University of Chicago.

Urey speculated that the early terrestrial atmosphere was composed of ammonia, methane, and hydrogen. One of his Chicago graduate students was Stanley L. Miller, who showed in the Miller–Urey experiment that, if such a mixture were exposed to electric sparks and water, it can interact to produce amino acids, commonly considered the building blocks of life. Work with isotopes of oxygen led to pioneering the new field of paleoclimatic research. In 1958, he accepted a post as a professor at large at the new University of California, San Diego (UCSD), where he helped create the science faculty. He was one of the founding members of UCSD's school of chemistry, which was created in 1960. He became increasingly interested in space science, and when Apollo 11 returned Moon rock samples from the Moon, Urey examined them at the Lunar Receiving Laboratory. Lunar astronaut Harrison Schmitt said that Urey approached him as a volunteer for a one-way mission to the Moon, stating "I will go, and I don't care if I don't come back." (Full article...)

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Nuclear technology news

10 December 2024 – Belarus–Russia relations, Nuclear risk during the Russian invasion of Ukraine

Belarusian President Alexander Lukashenko confirms the presence of nuclear weapons in his country, including Russia's Oreshnik missile system. (AP)

6 December 2024 – Belarus–Russia relations, Nuclear risk during the Russian invasion of Ukraine

Russian President Vladimir Putin and Belarusian President Alexander Lukashenko sign an agreement in Minsk, Belarus, offering security guarantees to Belarus including nuclear security and the possible use of Russian nuclear weapons in order to repel aggressions. (AP)

1 December 2024 – Ukraine–United States relations

U.S. National Security Advisor Jake Sullivan says that the United States will not return the nuclear weapons that they dismantled to Ukraine. (Reuters)

19 November 2024 – Russian invasion of Ukraine

Nuclear risk during the Russian invasion of Ukraine, Russia and weapons of mass destruction

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