|
Plutonium In The Environment
Since the mid-20th century, plutonium in the environment has been primarily produced by human activity. The first plants to produce plutonium for use in Cold War atomic bombs were the Hanford nuclear site in Washington, and the Mayak nuclear plant, in Chelyabinsk Oblast, Russia. Over a period of four decades, "both released more than 200 million curies of radioactive isotopes into the surrounding environment – twice the amount expelled in the Chernobyl disaster in each instance." The majority of plutonium isotopes are not short-lived on a geological timescale, though it has been argued that traces of the long-lived 244Pu isotope still exist in nature. This isotope has been found in lunar soil, meteorites, and in the Oklo natural reactor. However, one study on plutonium in marine sediments indicates that the atomic bomb fallout accounts for 66% of the 239Pu and 59% 240Pu in the English Channel. In contrast, nuclear reprocessing contributes the majority of the 238Pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium
Plutonium is a chemical element; it has symbol Pu and atomic number 94. It is a silvery-gray actinide metal that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states. It reacts with carbon, halogens, nitrogen, silicon, and hydrogen. When exposed to moist air, it forms oxides and hydrides that can expand the sample up to 70% in volume, which in turn flake off as a powder that is pyrophoric. It is radioactive and can accumulate in bones, which makes the handling of plutonium dangerous. Plutonium was first synthesized and isolated in late 1940 and early 1941, by deuteron bombardment of uranium-238 in the cyclotron at the University of California, Berkeley. First, neptunium-238 (half-life 2.1 days) was synthesized, which then beta-decayed to form the new element with atomic number 94 and atomic weight 238 (half-life 88 years). Since uranium had been named after the planet Uranus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geochemical Journal
The ''Geochemical Journal'' is a peer-reviewed open-access scientific journal covering all aspects of geochemistry and cosmochemistry. It is published by the Geochemical Society of Japan and the editor-in-chief is Katsuhiko Suzuki. Abstracting and indexing The journal is abstracted and indexed in: *CAB Abstracts *Chemical Abstracts Service *Current Contents/Physical, Chemical & Earth Sciences *Science Citation Index Expanded *Scopus According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 1.561. References External links * Academic journals established in 1966 English-language journals Geochemistry journals {{geochem-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Families, Atomic Cities, And The Great Soviet And American Plutonium Disasters
Nuclear may refer to: Physics Relating to the nucleus of the atom: *Nuclear engineering *Nuclear physics *Nuclear power *Nuclear reactor *Nuclear weapon *Nuclear medicine *Radiation therapy *Nuclear warfare Mathematics *Nuclear space *Nuclear operator * Nuclear congruence *Nuclear C*-algebra Biology Relating to the nucleus of the cell: * Nuclear DNA Society *Nuclear family, a family consisting of a pair of adults and their children Music * "Nuclear" (band), chilean thrash metal band * "Nuclear" (Ryan Adams song), 2002 *"Nuclear", a song by Mike Oldfield from his ''Man on the Rocks'' album * ''Nu.Clear'' (EP) by South Korean girl group CLC Films * ''Nuclear'' (film), a 2022 documentary by Oliver Stone. See also *Nucleus (other) *Nucleolus *Nucleation *Nucleic acid *Nucular ''Nucular'' is a common, proscribed pronunciation of the word "nuclear". It is a rough phonetic spelling of . The ''Oxford English Dictionary''s entry dates the word's first published appear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 until the dissolution of the Soviet Union in 1991. The term ''Cold war (term), cold war'' is used because there was no direct fighting between the two superpowers, though each supported opposing sides in regional conflicts known as proxy wars. In addition to the struggle for ideological and economic influence and an arms race in both conventional and Nuclear arms race, nuclear weapons, the Cold War was expressed through technological rivalries such as the Space Race, espionage, propaganda campaigns, Economic sanctions, embargoes, and sports diplomacy. After the end of World War II in 1945, during which the US and USSR had been allies, the USSR installed satellite state, satellite governments in its occupied territories in Eastern Europe and N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozyorsk, Chelyabinsk Oblast
Ozyorsk or Ozersk () is a closed city in Chelyabinsk Oblast, Russia. It had a population of 82,164 as of the 2010 census. History The town was founded on the shores of Lake Irtyash in 1947. Until 1994, it was known as Chelyabinsk-65, and even earlier, as Chelyabinsk-40 (the digits are the last digits of the postal code, and the name is that of the nearest big city, which was a common practice of giving names to closed towns). Codenamed City 40, Ozersk was the birthplace of the Soviet nuclear weapons program after the Second World War. In 1994, it was granted town status and renamed Ozyorsk. Administrative and municipal status Within the framework of administrative divisions, it has, together with six rural localities, official status as the Town of Ozyorsk—an administrative unit with a status equal to that of the districts.Resolution #161 As a municipal division, the town of Ozyorsk has the official name Ozyorsky Urban Okrug. Economy Ozyorsk was and remains a closed t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richland, Washington
Richland () is a city in Benton County, Washington, United States. It is located in southeastern Washington at the confluence of the Yakima River, Yakima and the Columbia River, Columbia Rivers. As of the 2020 census, the city's population was 60,560. Along with the nearby cities of Pasco, Washington, Pasco and Kennewick, Washington, Kennewick, Richland forms the Tri-Cities, Washington, Tri-Cities metropolitan area. The townsite was established in 1905 and incorporated as Richland in 1910. The U.S. Army acquired the city and surrounding areas in 1943 for the establishment of the Hanford site, Hanford nuclear site, part of the Manhattan Project during World War II. Richland was transformed into a bedroom community for Hanford workers and grew to 25,000 residents by the end of the war. The city remained under control of Hanford contractors until it was re-incorporated as a city in 1958. History For centuries, the village of Chemna stood at the mouth of the current Yakima River. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hanford N Reactor Adjusted
Hanford may refer to: Places *Hanford (constituency), a constituency in Tuen Mun, People's Republic of China *Hanford, Dorset, a village and parish in England *Hanford, Staffordshire, England *Hanford, California, United States *Hanford, Iowa, United States *Hanford, Washington, a community depopulated by the U.S. government in March 1943 Schools * Hanford School, a school in Hanford, Dorset * Hanford High School, a high school in Richland, Washington Other uses *Hanford (surname) *Hanford Site, a nuclear complex *Hanford Tri-State Airlines or Mid-Continent Airlines *USS Hanford, USS ''Hanford'' People with the given name * Hanford Dixon (born 1958), American football player and sports announcer * Hanford L. King Jr. (1921-1986), bishop of the Episcopal Diocese of Idaho * Hanford MacNider (1889–1968), American diplomat and US Army General See also *Handford, a surname *Hanford Carnegie Museum *Hanford Reach, a free-flowing section of the Columbia River *Hanford Reach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium-241
Plutonium-241 ( or Pu-241) is an isotope of plutonium formed when plutonium-240 captures a neutron. Like some other plutonium isotopes (especially 239Pu), 241Pu is fissile, with a neutron absorption cross section about one-third greater than that of 239Pu, and a similar probability of fissioning on neutron absorption, around 73%. In the non-fission case, neutron capture produces plutonium-242. In general, isotopes with an odd number of neutrons are both more likely to absorb a neutron and more likely to undergo fission on neutron absorption than isotopes with an even number of neutrons. Decay properties Plutonium-241 is a beta emitter with a half-life of 14.3 years, corresponding to a decay of about 5% of 241Pu nuclei over a one-year period. This decay has a ''Q''-value of and a mean of , and does not emit gamma rays. The longer spent nuclear fuel waits before reprocessing, the more 241Pu decays to americium-241, which is nonfissile (although fissionable by fast neutrons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium-238
Plutonium-238 ( or Pu-238) is a radioactive isotope of plutonium that has a half-life of 87.7 years. Plutonium-238 is a very powerful alpha emitter; as alpha particles are easily blocked, this makes the plutonium-238 isotope suitable for usage in radioisotope thermoelectric generators (RTGs) and radioisotope heater units. The density of plutonium-238 at room temperature is about 19.8 g/cc. The material will generate about 0.57 watts per gram of 238Pu. The bare sphere critical mass of metallic plutonium-238 is not precisely known, but its calculated range is between 9.04 and 10.07 kilograms. History Initial production Plutonium-238 was the first isotope of plutonium to be discovered. It was synthesized by Glenn Seaborg and his associates in December 1940 by bombarding uranium-238 with deuterons, creating neptunium-238. + → + 2 The neptunium isotope then undergoes β− decay to plutonium-238, with a half-life of 2.12 days: → + + Plutonium-238 natu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Reprocessing
Nuclear reprocessing is the chemical separation of fission products and actinides from spent nuclear fuel. Originally, reprocessing was used solely to extract plutonium for producing nuclear weapons. With commercialization of nuclear power, the reprocessed plutonium was recycled back into MOX nuclear fuel for thermal reactors. The reprocessed uranium, also known as the spent fuel material, can in principle also be re-used as fuel, but that is only economical when uranium supply is low and prices are high. Nuclear reprocessing may extend beyond fuel and include the reprocessing of other nuclear reactor material, such as Zircaloy cladding. The high radioactivity of spent nuclear material means that reprocessing must be highly controlled and carefully executed in advanced facilities by specialized personnel. Numerous processes exist, with the chemical based PUREX process dominating. Alternatives include heating to drive off volatile elements, burning via oxidation, and fluoride vola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
English Channel
The English Channel, also known as the Channel, is an arm of the Atlantic Ocean that separates Southern England from northern France. It links to the southern part of the North Sea by the Strait of Dover at its northeastern end. It is the busiest Sea lane, shipping area in the world. It is about long and varies in width from at its widest to at its narrowest in the Strait of Dover."English Channel". ''The Columbia Encyclopedia'', 2004. It is the smallest of the shallow seas around the continental shelf of Europe, covering an area of some . The Channel aided the United Kingdom in becoming a naval superpower, serving as a natural defence against invasions, such as in the Napoleonic Wars and in the World War II, Second World War. The northern, English coast of the Channel is more populous than the southern, French coast. The major languages spoken in this region are English language, English and French language, French. Names Roman historiography, Roman sources as (or , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plutonium-240
Plutonium-240 ( or Pu-240) is an isotope of plutonium formed when plutonium-239 captures a neutron. The detection of its spontaneous fission led to its discovery in 1944 at Los Alamos and had important consequences for the Manhattan Project. 240Pu undergoes spontaneous fission as a secondary decay mode at a small but significant rate. The presence of 240Pu limits plutonium's use in a nuclear bomb, because the neutron flux from spontaneous fission initiates the chain reaction prematurely, causing an early release of energy that physically disperses the core before full implosion is reached. It decays by alpha emission to uranium-236. Nuclear properties About 62% to 73% of the time when 239Pu captures a neutron, it undergoes fission; the remainder of the time, it forms 240Pu. The longer a nuclear fuel element remains in a nuclear reactor, the greater the relative percentage of 240Pu in the fuel becomes. The isotope 240Pu has about the same thermal neutron capture cros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
