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Oklo
Oklo is a region near Franceville in the Haut-Ogooué Province of Gabon. Several natural nuclear fission reactors were discovered in the uranium mines in the region in 1972. History Gabon was a French colony when prospectors from the Commissariat à l'énergie atomique (the industrial parts, which later became Orano Cycle) discovered uranium in the remote region in 1956. France immediately opened mines operated by Comuf () near Mounana village to exploit the vast mineral resources, and the state of Gabon was given a minority share in the company. For 40 years, France mined uranium in Gabon. Once extracted, the uranium was used for electricity production in France and much of Europe. Today the uranium deposits are exhausted, and the mine is no longer active. Currently, mine reclamation work is ongoing in the region affected by the mine operations. Natural nuclear fission reactor Some of the mined uranium was found to have a lower concentration of uranium-235 than expect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Nuclear Fission Reactor
A natural nuclear fission reactor is a uranium deposit where self-sustaining nuclear chain reactions occur. The idea of a nuclear reactor existing ''in situ'' within an ore body moderated by groundwater was briefly explored by Paul Kuroda in 1956. The existence of an extinct or fossil nuclear fission reactor, where self-sustaining nuclear reactions have occurred in the past, are established by analysis of isotope ratios of uranium and of the fission products (and the stable daughter nuclides of those fission products). The first discovery of such a reactor happened in 1972 in Oklo, Gabon, by researchers from the French Alternative Energies and Atomic Energy Commission (CEA) when chemists performing quality control for the French nuclear industry noticed sharp depletions of fissile in gaseous uranium made from Gabonese ore. Oklo is the only location where this phenomenon is known to have occurred, and consists of 16 sites with patches of centimeter-sized ore layers. There, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Reactor
A nuclear reactor is a device used to initiate and control a Nuclear fission, fission nuclear chain reaction. They are used for Nuclear power, commercial electricity, nuclear marine propulsion, marine propulsion, Weapons-grade plutonium, weapons production and Research reactor, research. Fissile material, Fissile nuclei (primarily uranium-235 or plutonium-239) absorb single neutron, neutrons and split, releasing energy and multiple neutrons, which can induce further fission. Reactors stabilize this, regulating Neutron absorber, neutron absorbers and neutron moderator, moderators in the core. Fuel efficiency is exceptionally high; Enriched uranium#Low-enriched uranium (LEU), low-enriched uranium is 120,000 times more energy dense than coal. Heat from nuclear fission is passed to a working fluid Nuclear reactor#By coolant, coolant. In commercial reactors, this drives Turbine, turbines and electrical generator shafts. Some reactors are used for district heating, and isotopes, isoto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium Mines
Uranium production is carried out in about 13 countries around the world, in 2017 producing a cumulative total of 59,462 tonnes of uranium (tU). The international producers were Kazakhstan (39%), Canada (22%), Australia (10%), Namibia (7.1%), Niger (5.8%), Russian Federation (4.9%), Uzbekistan (4.0%), China (3.2%), United States (1.6%), Ukraine (0.9%), India (0.7%), South Africa (0.5%) and Pakistan (0.1%). Since 2009 the in-situ leach (ISL) mining operations in Kazakhstan have been producing the largest share of world uranium. The largest conventional uranium mines are Cigar Lake and McArthur River (Canada); Ranger and Olympic Dam (Australia); Krasnokamensk (Russia) and Rossing (Namibia). The largest uranium producers are Cameco, Rio Tinto, Areva, KazAtomProm and ARMZ-TVEL. The production methods employed are conventional underground and open cast (50%) and in-situ leaching (50%). About 50 uranium production centers are operational. Viable projects Potentially viable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium
Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium radioactive decay, radioactively decays, usually by emitting an alpha particle. The half-life of this decay varies between 159,200 and 4.5 billion years for different isotopes of uranium, isotopes, making them useful for dating the age of the Earth. The most common isotopes in natural uranium are uranium-238 (which has 146 neutrons and accounts for over 99% of uranium on Earth) and uranium-235 (which has 143 neutrons). Uranium has the highest atomic weight of the primordial nuclide, primordially occurring elements. Its density is about 70% higher than that of lead and slightly lower than that of gold or tungsten. It occurs naturally in low concentrations of a few Parts-per notation#Parts-per expressions, parts per million in soil, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franceville
Franceville is one of the four largest cities in Gabon, with a population of 110,568 at the 2013 census. It lies on the Mpassa River and at the end of the Trans-Gabon Railway and the N3 road. It grew from a village named Masuku. Overview Pierre Savorgnan de Brazza chose the village of Masuku to resettle former slaves and renamed it Francheville (meaning "city of the freed") in 1880. This name later was modified to Franceville, after the country’s former ruler (meaning "city of France"). Features of the town include St Hilaire's Church (built in 1899), a large statue of President Omar Bongo (who was born in Franceville), a primate medical research institute, and a golf course. Its airport is west, in Mvengué. Bongo was buried in Franceville on June 18, 2009. There is a market where numerous items can be purchased, including clothing, fruit and vegetables, electronics, meats, and the market also sells bushmeat, which includes Central African rock python, monkey and lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statherian
The Statherian Period (; , meaning "stable, firm") is the final geologic period in the Paleoproterozoic Era and lasted from Mya to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. The period was characterized on most continents by either new platforms or final cratonization of fold belts. Oxygen levels were 10% to 20% of current values. '' Rafatazmia'', controversially claimed to be present in Statherian beds in India, may be the oldest known confirmably eukaryotic fossil organism. By the beginning of the Statherian, the supercontinent Columbia had assembled. Approximately 1.7 billion years ago, natural nuclear fission reactors were generating power in what is now Oklo, Gabon Gabon ( ; ), officially the Gabonese Republic (), is a country on the Atlantic coast of Central Africa, on the equator, bordered by Equatorial Guinea to the northwest, Cameroon to the north, the Republic of the Congo to the east and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gabon
Gabon ( ; ), officially the Gabonese Republic (), is a country on the Atlantic coast of Central Africa, on the equator, bordered by Equatorial Guinea to the northwest, Cameroon to the north, the Republic of the Congo to the east and south, and the Gulf of Guinea to the west. It has an area of and a population of million people. There are coastal plains, mountains (the Crystal Mountains (Africa), Cristal Mountains and the Chaillu Massif in the centre), and a savanna in the east. Libreville is the country's capital and largest city. Gabon's original inhabitants were the African Pygmies, Bambenga. In the 14th century, Bantu expansion, Bantu migrants also began settling in the area. The Kingdom of Orungu was established around 1700. France colonised the region in the late 19th century. Since its independence from France in 1960, Gabon has had four President of Gabon, presidents. In the 1990s, it introduced a multi-party system and a democratic constitution that aimed for a more tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radioactive Waste Repositories
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered ''radioactive''. Three of the most common types of decay are alpha, beta, and gamma decay. The weak force is the mechanism that is responsible for beta decay, while the other two are governed by the electromagnetic and nuclear forces. Radioactive decay is a random process at the level of single atoms. According to quantum theory, it is impossible to predict when a particular atom will decay, regardless of how long the atom has existed. However, for a significant number of identical atoms, the overall decay rate can be expressed as a decay constant or as a half-life. The half-lives of radioactive atoms have a huge range: from nearly instantaneous to far longer than the age of the universe. The decaying nucleus is called the parent ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gabon Geology Oklo
Gabon ( ; ), officially the Gabonese Republic (), is a country on the Atlantic coast of Central Africa, on the equator, bordered by Equatorial Guinea to the northwest, Cameroon to the north, the Republic of the Congo to the east and south, and the Gulf of Guinea to the west. It has an area of and a population of million people. There are coastal plains, mountains (the Crystal Mountains (Africa), Cristal Mountains and the Chaillu Massif in the centre), and a savanna in the east. Libreville is the country's capital and largest city. Gabon's original inhabitants were the African Pygmies, Bambenga. In the 14th century, Bantu expansion, Bantu migrants also began settling in the area. The Kingdom of Orungu was established around 1700. France colonised the region in the late 19th century. Since its independence from France in 1960, Gabon has had four President of Gabon, presidents. In the 1990s, it introduced a multi-party system and a democratic constitution that aimed for a more tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mines In Gabon
Mine, mines, miners or mining may refer to: Extraction or digging *Miner, a person engaged in mining or digging *Mining, extraction of mineral resources from the ground through a mine Grammar *Mine, a first-person English possessive pronoun Military * Mining (military), digging under a fortified military position to penetrate its defenses * Mine warfare ** Anti-tank mine, a land mine made for use against armored vehicles ** Antipersonnel mine, a land mine targeting people walking around, either with explosives or poison gas ** Bangalore mine, colloquial name for the Bangalore torpedo, a man-portable explosive device for clearing a path through wire obstacles and land mines ** Cluster bomb, an aerial bomb which releases many small submunitions, which often act as mines ** Land mine, explosive mines placed under or on the ground ** Naval mine, or sea mine, a mine at sea, either floating or on the sea bed, often dropped via parachute from aircraft, or otherwise lain by surface sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron Moderator
In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, ideally without capturing any, leaving them as thermal neutrons with only minimal (thermal) kinetic energy. These thermal neutrons are immensely more susceptible than fast neutrons to propagate a nuclear chain reaction of uranium-235 or other fissile isotope by colliding with their atomic nucleus. Water (sometimes called "light water" in this context) is the most commonly used moderator (roughly 75% of the world's reactors). Solid graphite (20% of reactors) and heavy water (5% of reactors) are the main alternatives. Beryllium has also been used in some experimental types, and hydrocarbons have been suggested as another possibility. Moderation Neutrons are normally bound into an atomic nucleus and do not exist free for long in nature. The unbound neutron has a half-life of 10 minutes and 11 seconds. The release of neutrons from the nucleus requires exceeding the binding ener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
