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. Generating electricity from fusion power remains the focus of international research. (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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  Over 2,000 nuclear tests 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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  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 photograph of Sumiteru Taniguchi's back injuries taken in January 1946 by a U.S. Marine photographer (from Nuclear weapon)
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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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  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 cooling towers of the Philippsburg Nuclear Power Plant in Germany (from Nuclear fission)
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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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  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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  Anti-nuclear weapons protest march in Oxford, 1980 (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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  The Torness nuclear power station – an AGR (from Nuclear reactor)
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  Otto Hahn and Lise Meitner in 1912 (from Nuclear fission)
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  The Ikata Nuclear Power Plant, a pressurized water reactor that cools by utilizing 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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  Nuclear fuel assemblies being inspected before entering a pressurized water reactor in the United States (from Nuclear power)
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  Scaled-down model of TOPAZ nuclear reactor (from Nuclear reactor)
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  Protest in Bonn against the nuclear arms race between the U.S./NATO and the Warsaw Pact, 1981 (from Nuclear weapon)
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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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  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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  Mushroom cloud from the explosion of Castle Bravo, the largest nuclear weapon detonated by the U.S., in 1954 (from Nuclear weapon)
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  Diablo Canyon – a PWR (from Nuclear reactor)
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  Treatment of the interior part of a VVER-1000 reactor frame at Atommash (from Nuclear reactor)
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  Some of the Chicago Pile Team, including Enrico Fermi and Leó Szilárd (from Nuclear reactor)
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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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  Growth of worldwide nuclear power generation (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 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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  Anti-nuclear protest near nuclear waste disposal centre at Gorleben in northern Germany (from Nuclear power)
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  Drawing of the first artificial reactor, Chicago Pile-1. (from Nuclear fission)
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  Lise Meitner and Otto Hahn in their laboratory (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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  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 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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  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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  Demonstration against nuclear testing in Lyon, France, in the 1980s. (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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  The CANDU Qinshan Nuclear Power Plant (from Nuclear reactor)
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  Schematic of the ITER tokamak under construction in France (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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  The Ignalina Nuclear Power Plant – a RBMK type (closed 2009) (from Nuclear reactor)
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  The status of nuclear power globally (click for legend) (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)
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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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  Core of CROCUS, a small nuclear reactor used for research at the EPFL in Switzerland (from Nuclear reactor)
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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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  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 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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  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 Calder Hall nuclear power station in the United Kingdom, the world's first commercial nuclear power station. (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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  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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  Share of electricity production from nuclear, 2022 (from Nuclear power)
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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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  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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  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 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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  Death rates from air pollution and accidents related to energy production, measured in deaths in the past per terawatt hours (TWh) (from Nuclear power)
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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 multi-mission radioisotope thermoelectric generator (MMRTG), used in several space missions such as the Curiosity Mars rover (from Nuclear power)
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  The Leibstadt Nuclear Power Plant in Switzerland (from Nuclear power)
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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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  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 mushroom cloud of the atomic bomb dropped on Nagasaki, Japan, on 9 August 1945 rose over 18 kilometres (11 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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  Activity of spent UOx fuel in comparison to the activity of natural uranium ore over time (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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  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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  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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  Dry cask storage vessels storing spent nuclear fuel assemblies (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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  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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  The two basic fission weapon designs (from Nuclear weapon)
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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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  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 Magnox Sizewell A nuclear power station (from Nuclear reactor)
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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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  Life-cycle greenhouse gas emissions of electricity supply technologies, median values calculated by IPCC (from Nuclear power)
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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 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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  Ukrainian workers use equipment provided by the U.S. 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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  In thermal nuclear reactors (LWRs in specific), the coolant acts as a moderator that must slow down the neutrons before they can be efficiently absorbed by the fuel. (from Nuclear reactor)
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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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  The Superphénix, closed in 1998, was one of the few FBRs. (from Nuclear reactor)
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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)

Selected article -

Krakatau subcritical experiment being lowered into the floor of the tunnel of the U1a Complex at the Nevada Test Site (2006). The cables extending from the hole will carry data from the experiment to recording instruments.

Following the success of Operation Grapple in which the United Kingdom became the third nation to acquire thermonuclear weapons after the United States and the Soviet Union, Britain launched negotiations with the US on a treaty under in which both could share information and material to design, test and maintain their nuclear weapons. This effort culminated in the 1958 US–UK Mutual Defence Agreement. One of the results of that treaty was that Britain was allowed to use United States' Nevada Test Site for testing their designs and ideas, and received full support from the personnel there, in exchange for the data "take" from the experiment, a mutual condition. In effect the Nevada Test Site became Britain's test ground, subject only to advance planning and integrating their testing into that of the United States. This resulted in 24 underground tests at the Nevada Test Site from 1958 through the end of nuclear testing in the US in September 1992.

The United Kingdom signed the Comprehensive Nuclear Test Ban Treaty in 1996 and ratified it in 1998, confirming the British commitment towards ending nuclear test explosions in the world. (Full article...)

More selected articles

Selected picture -

Pictured is an Officer of the watch aboard HMS Vanguard. The Royal Navy has operated the UK’s Continuous at Sea Deterrent since 1967 when the first SSBN – or Ship Submersible Ballistic Nuclear – HMS Resolution began patrolling armed with the Polaris missile system. In 1996 HMS Vanguard, the first submarine armed with the Trident missile system, arrived on the Clyde and took over deterrent patrol duties from the Resolution Class. The four Vanguard-class submarines form the UK's strategic nuclear deterrent force. Each of the four boats are armed with Trident 2 D5 nuclear missiles. Like all submarines the Vanguard Class are steam powered, their reactors converting water into steam to drive the engines and generate electricity.

Did you know?

• ... that Project Ketch proposed the detonation of a 24-kiloton nuclear device in Pennsylvania to create a natural-gas storage reservoir?
• ... 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 the British Tychon missile was developed from a Barnes Wallis concept to keep strike aircraft safe while dropping nuclear bombs?
• ... that during World War II, pilot G. E. Clements was removed from training for secret missions associated with the Manhattan Project when senior officers realized she was a woman?
• ... 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 after journalist Adele Ferguson's criticism of the U.S. Navy's sex discrimination attracted nationwide attention, she was offered a personal tour of a nuclear submarine?

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Selected biography -

Enrico Fermi (Italian: [enˈriːko ˈfermi]; 29 September 1901 – 28 November 1954) was an Italian and later naturalized American physicist, renowned for being the creator of the world's first nuclear reactor, the Chicago Pile-1, and a member of the Manhattan Project. He has been called the "architect of the nuclear age" and the "architect of the atomic bomb". He was one of very few physicists to excel in both theoretical physics and experimental physics. Fermi was awarded the 1938 Nobel Prize in Physics for his work on induced radioactivity by neutron bombardment and for the discovery of transuranium elements. With his colleagues, Fermi filed several patents related to the use of nuclear power, all of which were taken over by the US government. He made significant contributions to the development of statistical mechanics, quantum theory, and nuclear and particle physics.

Fermi's first major contribution involved the field of statistical mechanics. After Wolfgang Pauli formulated his exclusion principle in 1925, Fermi followed with a paper in which he applied the principle to an ideal gas, employing a statistical formulation now known as Fermi–Dirac statistics. Today, particles that obey the exclusion principle are called "fermions". Pauli later postulated the existence of an uncharged invisible particle emitted along with an electron during beta decay, to satisfy the law of conservation of energy. Fermi took up this idea, developing a model that incorporated the postulated particle, which he named the "neutrino". His theory, later referred to as Fermi's interaction and now called weak interaction, described one of the four fundamental interactions in nature. Through experiments inducing radioactivity with the recently discovered neutron, Fermi discovered that slow neutrons were more easily captured by atomic nuclei than fast ones, and he developed the Fermi age equation to describe this. After bombarding thorium and uranium with slow neutrons, he concluded that he had created new elements. Although he was awarded the Nobel Prize for this discovery, the new elements were later revealed to be nuclear fission products.

Fermi left Italy in 1938 to escape new Italian racial laws that affected his Jewish wife, Laura Capon. He emigrated to the United States, where he worked on the Manhattan Project during World War II. Fermi led the team at the University of Chicago that designed and built Chicago Pile-1, which went critical on 2 December 1942, demonstrating the first human-created, self-sustaining nuclear chain reaction. He was on hand when the X-10 Graphite Reactor at Oak Ridge, Tennessee went critical in 1943, and when the B Reactor at the Hanford Site did so the next year. At Los Alamos, he headed F Division, part of which worked on Edward Teller's thermonuclear "Super" bomb. He was present at the Trinity test on 16 July 1945, the first test of a full nuclear bomb explosion, where he used his Fermi method to estimate the bomb's yield.

After the war, he helped establish the Institute for Nuclear Studies at Chicago, and served on the General Advisory Committee, chaired by J. Robert Oppenheimer, which advised the Atomic Energy Commission on nuclear matters. After the detonation of the first Soviet fission bomb in August 1949, he strongly opposed the development of a hydrogen bomb on both moral and technical grounds. He was among the scientists who testified on Oppenheimer's behalf at the 1954 hearing that resulted in the denial of Oppenheimer's security clearance.

Fermi did important work in particle physics, especially related to pions and muons, and he speculated that cosmic rays arose when material was accelerated by magnetic fields in interstellar space. Many awards, concepts, and institutions are named after Fermi, including the Fermi 1 (breeder reactor), the Enrico Fermi Nuclear Generating Station, the Enrico Fermi Award, the Enrico Fermi Institute, the Fermi National Accelerator Laboratory (Fermilab), the Fermi Gamma-ray Space Telescope, the Fermi paradox, and the synthetic element fermium, making him one of 16 scientists who have elements named after them. (Full article...)

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Nuclear technology news

14 May 2024 –

Russia places its nuclear capable submarine-launched Bulava intercontinental ballistic missile into service. (Reuters)

9 May 2024 – Joint Comprehensive Plan of Action, Iran–Israel relations

Iran warns that it will build a nuclear weapon if Israel continues to target its nuclear facilities. (Al Jazeera)

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