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 two basic fission weapon designs (from Nuclear weapon)
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  Share of electricity production from nuclear, 2023 (from Nuclear power)
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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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  Life-cycle greenhouse gas emissions of electricity supply technologies, median values calculated by IPCC (from Nuclear power)
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  The Magnox Sizewell A nuclear power station (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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  The "curve of binding energy": A graph of binding energy per nucleon of common isotopes. (from Nuclear fission)
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  Schematic of the ITER tokamak under construction in France (from Nuclear power)
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  Drawing of the first artificial reactor, Chicago Pile-1 (from Nuclear fission)
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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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  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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  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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  Demonstration against nuclear testing in Lyon, France, in the 1980s (from Nuclear weapon)
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  The Ignalina Nuclear Power Plant – a RBMK type (closed 2009) (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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  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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  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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  The Leibstadt Nuclear Power Plant in Switzerland (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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  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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  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 cooling towers of the Philippsburg Nuclear Power Plant in Germany (from Nuclear fission)
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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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  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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  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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  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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  The CANDU Qinshan Nuclear Power Plant (from Nuclear reactor)
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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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  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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  Anti-nuclear protest near nuclear waste disposal centre at Gorleben in northern Germany (from Nuclear power)
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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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  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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  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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  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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  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 Torness nuclear power station – an AGR (from Nuclear reactor)
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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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  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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  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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  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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  Scaled-down model of TOPAZ nuclear reactor (from Nuclear reactor)
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  Dry cask storage vessels storing spent nuclear fuel assemblies (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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  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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  Protest in Bonn against the nuclear arms race between the US/NATO and the Warsaw Pact, 1981 (from Nuclear weapon)
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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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  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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  Anti-nuclear weapons protest march in Oxford, 1980 (from Nuclear weapon)
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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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  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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  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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  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 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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  Lise Meitner and Otto Hahn in their laboratory (from Nuclear reactor)
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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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  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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  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 Superphénix, closed in 1998, was one of the few FBRs. (from Nuclear reactor)
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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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  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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  Treatment of the interior part of a VVER-1000 reactor frame at Atommash (from Nuclear reactor)
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  Diablo Canyon – a PWR (from Nuclear reactor)
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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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  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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  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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  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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  Otto Hahn and Lise Meitner in 1912 (from Nuclear fission)
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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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  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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  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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  Some of the Chicago Pile Team, including Enrico Fermi and Leó Szilárd (from Nuclear reactor)
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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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  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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  The status of nuclear power globally (click for legend) (from Nuclear power)
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  Growth of worldwide nuclear power generation (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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  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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  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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  A photograph of Sumiteru Taniguchi's back injuries taken in January 1946 by a US Marine photographer (from Nuclear weapon)
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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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  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)

Selected article -

Thorium is a chemical element; it has symbol Th and atomic number 90. Thorium is a weakly radioactive light silver metal which tarnishes olive grey when it is exposed to air, forming thorium dioxide; it is moderately soft, malleable, and has a high melting point. Thorium is an electropositive actinide whose chemistry is dominated by the +4 oxidation state; it is quite reactive and can ignite in air when finely divided.

All known thorium isotopes are unstable. The most stable isotope, ²³²Th, has a half-life of 14.05 billion years, or about the age of the universe; it decays very slowly via alpha decay, starting a decay chain named the thorium series that ends at stable ²⁰⁸Pb. On Earth, thorium and uranium are the only elements with no stable or nearly-stable isotopes that still occur naturally in large quantities as primordial elements. Thorium is estimated to be over three times as abundant as uranium in the Earth's crust, and is chiefly refined from monazite sands as a by-product of extracting rare-earth elements.

Thorium was discovered in 1828 by the Norwegian amateur mineralogist Morten Thrane Esmark and identified by the Swedish chemist Jöns Jacob Berzelius, who named it after Thor, the Norse god of thunder and war, because of its power. Its first applications were developed in the late 19th century. Thorium's radioactivity was widely acknowledged during the first decades of the 20th century. In the second half of the century, thorium was replaced in many uses due to concerns about its radioactivity.

Thorium is still being used as an alloying element in TIG welding electrodes but is slowly being replaced in the field with different compositions. It was also material in high-end optics and scientific instrumentation, used in some broadcast vacuum tubes, and as the light source in gas mantles, but these uses have become marginal. It has been suggested as a replacement for uranium as nuclear fuel in nuclear reactors, and several thorium reactors have been built. Thorium is also used in strengthening magnesium, coating tungsten wire in electrical and welding equipment, controlling the grain size of tungsten in electric lamps, high-temperature crucibles, and glasses including camera and scientific instrument lenses. Other uses for thorium include heat-resistant ceramics, aircraft engines, and in light bulbs. Ocean science has utilised ²³¹Pa/²³⁰Th isotope ratios to understand the ancient ocean. (Full article...)

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Selected picture -

Credit: Unknown (see OTRS also)

Interior of an Ames Process pressure vessel with slag coating the outside and bottom (after reaction and removal of uranium metal). ~1943
Attribution: The Ames Laboratory, USDOE (http://www.ameslab.gov/)

Did you know?

• ... that poet Peggy Pond Church became a strong pacifist and a member of the Society of Friends after the Manhattan Project used her home as a place to build nuclear weapons?
• ... that Jeya Wilson invited New Zealand prime minister David Lange to debate the moral indefensibility of nuclear weapons at the Oxford Union?
• ... that before becoming a successful children's author, Myron Levoy was an engineer doing research on nuclear-powered spaceships for a mission to Mars?
• ... that Project Ketch proposed the detonation of a 24-kiloton nuclear device in Pennsylvania to create a natural-gas storage reservoir?
• ... that T. K. Jones thought that a nuclear war was survivable if "there are enough shovels to go around"?
• ... that the medieval Castle Knob was the site of a Cold War nuclear monitoring station?

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Selected biography -

William Sterling Parsons (26 November 1901 – 5 December 1953) was an American naval officer who worked as an ordnance expert on the Manhattan Project during World War II. He is best known for being the weaponeer on the Enola Gay, the aircraft which dropped an atomic bomb on Hiroshima, Japan, in 1945. To avoid the possibility of a nuclear explosion if the aircraft crashed and burned on takeoff, he decided to arm the bomb in flight. While the aircraft was en route to Hiroshima, Parsons climbed into the cramped and dark bomb bay, and inserted the powder charge and detonator. He was awarded the Silver Star for his part in the mission.

A 1922 graduate of the United States Naval Academy, Parsons served on a variety of warships beginning with the battleship USS Idaho. He was trained in ordnance and studied ballistics under L. T. E. Thompson at the Naval Proving Ground in Dahlgren, Virginia. In July 1933, Parsons became liaison officer between the Bureau of Ordnance and the Naval Research Laboratory. He became interested in radar and was one of the first to recognize its potential to locate ships and aircraft, and perhaps even track shells in flight. In September 1940, Parsons and Merle Tuve of the National Defense Research Committee began work on the development of the proximity fuze, an invention that was provided to the US by the UK Tizard Mission, a radar-triggered fuze that would explode a shell in the proximity of the target. The fuze, eventually known as the VT (variable time) fuze, Mark 32, went into production in 1942. Parsons was on hand to watch the cruiser USS Helena shoot down the first enemy aircraft with a VT fuze in the Solomon Islands in January 1943.

In June 1943, Parsons joined the Manhattan Project as Associate Director at the Project Y research laboratory at Los Alamos, New Mexico, under J. Robert Oppenheimer. Parsons became responsible for the ordnance aspects of the project, including the design and testing of the non-nuclear components of nuclear weapons. In a reorganization in 1944, he lost responsibility for the implosion-type fission weapon, but retained that for the design and development of the gun-type fission weapon, which eventually became Little Boy. He was also responsible for the delivery program, codenamed Project Alberta. He watched the Trinity nuclear test from a B-29.

After the war, Parsons was promoted to the rank of rear admiral without ever having commanded a ship. He participated in Operation Crossroads, the nuclear weapon tests at Bikini Atoll in 1946, and later the Operation Sandstone tests at Enewetak Atoll in 1948. In 1947, he became deputy commander of the Armed Forces Special Weapons Project. He died of a heart attack in 1953. (Full article...)

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Nuclear technology news

14 December 2024 – 2024 New Jersey drone sightings

The Public Service Enterprise Group files a request with the Federal Aviation Administration to close the airspace over two of its nuclear power plants to all aircraft after unidentified drones were spotted hovering over the facilities in New Jersey. (The New York Post via MSN)

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)

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