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Hyperion Power Generation
Gen4 Energy, Inc (formerly Hyperion Power Generation, Inc.Hyperion Power Generation Inc. Announces Change of Company Name to Gen4 Energy, Inc. 13 March 2012, BusinessWire) was a privately held formed to construct and sell several designs of relatively small (70 MW thermal, 25 MW electric) s, which they claimed would be |
Private Company
A privately held company (or simply a private company) is a company whose shares and related rights or obligations are not offered for public subscription or publicly negotiated in the respective listed markets, but rather the company's stock is offered, owned, traded, exchanged privately, or Over-the-counter (finance), over-the-counter. In the case of a closed corporation, there are a relatively small number of shareholders or company members. Related terms are closely-held corporation, unquoted company, and unlisted company. Though less visible than their public company, publicly traded counterparts, private companies have major importance in the world's economy. In 2008, the 441 list of largest private non-governmental companies by revenue, largest private companies in the United States accounted for ($1.8 trillion) in revenues and employed 6.2 million people, according to ''Forbes''. In 2005, using a substantially smaller pool size (22.7%) for comparison, the 339 companies on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium Hydride
Uranium hydride, also called uranium trihydride (UH3), is an inorganic compound and a hydride of uranium. Properties Uranium hydride is a highly toxic, brownish grey to brownish black pyrophoric powder or brittle solid. Its density at 20 °C is 10.95 g cm−3, much lower than that of uranium (19.1 g cm−3). It has a metallic conductivity, is slightly soluble in hydrochloric acid and decomposes in nitric acid. Two crystal modifications of uranium hydride exist, both cubic: an α form that is obtained at low temperatures and a β form that is grown when the formation temperature is above 250 °C. After growth, both forms are metastable at room temperature and below, but the α form slowly converts to the β form upon heating to 100 °C. Both α- and β-UH3 are ferromagnetic at temperatures below ~180 K. Above 180 K, they are paramagnetic. Formation in uranium metal Hydrogen gas reaction Exposure of uranium metal to hydrogen leads to hydrogen embrittlement. Hydrog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alfa Class Submarine
The Alfa class, Soviet designation Project 705 Lira (russian: Лира, meaning "Lyre", NATO reporting name Alfa), was a class of nuclear-powered attack submarines in service with the Soviet Navy from 1971 into the early 1990s, with one serving later with the Russian Navy until 1996. They were the fastest military submarines ever built, with only the prototype submarine (NATO reporting name Papa-class) exceeding them in submerged speed. The Project 705 submarines had a unique design among other submarines. In addition to the revolutionary use of titanium for its hull, it used a powerful lead-bismuth cooled fast reactor as a power source, which greatly reduced the size of the reactor compared to conventional designs, thus reducing the overall size of the submarine, and allowing for very high speeds. However, it also meant that the reactor had a short lifetime and had to be kept warm when it was not being used. As a result, the submarines were used as interceptors, mostly kept i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk ( Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Conductivity
The thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by k, \lambda, or \kappa. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity. For instance, metals typically have high thermal conductivity and are very efficient at conducting heat, while the opposite is true for insulating materials like Rockwool or Styrofoam. Correspondingly, materials of high thermal conductivity are widely used in heat sink applications, and materials of low thermal conductivity are used as thermal insulation. The reciprocal of thermal conductivity is called thermal resistivity. The defining equation for thermal conductivity is \mathbf = - k \nabla T, where \mathbf is the heat flux, k is the thermal conductivity, and \nabla T is the temperature gradient. This is known as Fourier's Law for heat conduction. Although commonly expressed as a scalar, the most general form of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Water Nuclear Reactor
The light-water reactor (LWR) is a type of thermal-neutron reactor that uses normal water, as opposed to heavy water, as both its coolant and neutron moderator; furthermore a solid form of fissile elements is used as fuel. Thermal-neutron reactors are the most common type of nuclear reactor, and light-water reactors are the most common type of thermal-neutron reactor. There are three varieties of light-water reactors: the pressurized water reactor (PWR), the boiling water reactor (BWR), and (most designs of) the supercritical water reactor (SCWR). History Early concepts and experiments After the discoveries of fission, moderation and of the theoretical possibility of a nuclear chain reaction, early experimental results rapidly showed that natural uranium could only undergo a sustained chain reaction using graphite or heavy water as a moderator. While the world's first reactors ( CP-1, X10 etc.) were successfully reaching criticality, uranium enrichment began to develop from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium Oxide
Uranium oxide is an oxide of the element uranium. The metal uranium forms several oxides: * Uranium dioxide or uranium(IV) oxide (UO2, the mineral uraninite or pitchblende) * Diuranium pentoxide or uranium(V) oxide (U2O5) * Uranium trioxide or uranium(VI) oxide (UO3) * Triuranium octoxide (U3O8), the most stable uranium oxide; yellowcake typically contains 70 to 90 percent triuranium octoxide) * Uranyl peroxide (UO2O2 or UO4) * Amorphous uranium(VI) oxide (''Am''-U2O7) Uranium dioxide is oxidized in contact with oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ... to form triuranium octoxide. :3 UO2 + O2 → U3O8; at 700 °C (970 K) Preparation 38 During World War II, "Preparation 38" was the codename for uranium oxide used by German scientists. References Oxides Ur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperion Power Facility Concept
Hyperion may refer to: Greek mythology * Hyperion (Titan), one of the twelve Titans * ''Hyperion'', a byname of the Sun, Helios * Hyperion of Troy or Yperion, son of King Priam Science * Hyperion (moon), a moon of the planet Saturn * ''Hyperion'' (beetle), a genus of beetles in the family Carabidae * Hyperion (tree), a coast redwood in Northern California and the world's tallest known living tree * Hyperion proto-supercluster, a supercluster of galaxy groups discovered in 2018 * Project Hyperion (interstellar), preliminary study of a crewed interstellar starship or generation ship Literature * ''Hyperion'' (Hölderlin novel), a 1799 book by Friedrich Hölderlin * ''Hyperion'' (poem), a 1819 poem by John Keats * ''Hyperion'' (Longfellow novel), an 1839 book by Henry Wadsworth Longfellow * ''Hyperion'' (Simmons novel), a 1989 novel by Dan Simmons ** ''Hyperion Cantos'', the series of novels that started with ''Hyperion'' * ''Hyperion'' (magazine), a 1908–1910 Germ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen-moderated Self-regulating Nuclear Power Module
The hydrogen-moderated self-regulating nuclear power module (HPM), also referred to as the compact self-regulating transportable reactor (ComStar), is a type of nuclear power reactor using hydride as a neutron moderator. The design is inherently safe, as the fuel and the neutron moderator is uranium hydride UH3, which is reduced at high temperatures (500–800 °C) to uranium and hydrogen. The gaseous hydrogen exits the core, being absorbed by hydrogen absorbing material such as depleted uranium, thus making it less critical. This means that with rising temperature the neutron moderation drops and the nuclear fission reaction in the core is dampened, leading to a lower core temperature. This means as more energy is taken out of the core the moderation rises and the fission process is stoked to produce more heat. The concept for this type of nuclear reactor was developed by the scientists Otis Peterson and Robert Kimpland of the Los Alamos National Laboratory (LANL) in New Mexico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fast Reactor
A fast-neutron reactor (FNR) or fast-spectrum reactor or simply a fast reactor is a category of nuclear reactor in which the fission chain reaction is sustained by fast neutrons (carrying energies above 1 MeV or greater, on average), as opposed to slow thermal neutrons used in thermal-neutron reactors. Such a fast reactor needs no neutron moderator, but requires fuel that is relatively rich in fissile material when compared to that required for a thermal-neutron reactor. Around 20 land based fast reactors have been built, accumulating over 400 reactor years of operation globally. The largest of this was the Superphénix Sodium cooled fast reactor in France that was designed to deliver 1,242 MWe. Fast reactors have been intensely studied since the 1950s, as they provide certain decisive advantages over the existing fleet of water cooled and water moderated reactors. These are: * More neutrons are produced when a fission occurs, resulting from the absorption of a fast neutron, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead-bismuth Eutectic
Lead-Bismuth Eutectic or LBE is a eutectic alloy of lead (44.5 at%) and bismuth (55.5 at%) used as a coolant in some nuclear reactors, and is a proposed coolant for the lead-cooled fast reactor, part of the Generation IV reactor initiative. It has a melting point of 123.5 °C/255.3 °F (pure lead melts at 327 °C/621 °F, pure bismuth at 271 °C/520 °F) and a boiling point of 1,670 °C/3,038 °F. Lead-bismuth alloys with between 30% and 75% bismuth all have melting points below 200 °C/392 °F. Alloys with between 48% and 63% bismuth have melting points below 150 °C/302 °F. While lead expands slightly on melting and bismuth contracts slightly on melting, LBE has negligible change in volume on melting. History The Soviet Alfa-class submarines used LBE as a coolant for their nuclear reactors throughout the Cold War. The Russians are the acknowledged experts in lead-bismuth cooled reactors, with OKB Gidropress (the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium Nitride
Uranium nitrides is any of a family of several ceramic materials: uranium mononitride (UN), uranium sesquinitride (U2N3) and uranium dinitride (UN2). The word nitride refers to the −3 oxidation state of the nitrogen bound to the uranium. Uranium nitride has been considered as a potential nuclear fuel, nuclear fuel and will be used as such in the BREST-300 nuclear reactor currently under construction in Russia. It is said to be safer, stronger, denser, more thermally conductive and having a higher temperature tolerance. Challenges to implementation of the fuel include a complex conversion route from enriched UF6, the need to prevent oxidation during manufacturing and the need to define and license a final disposal route. The necessity to use expensive, highly isotopically enriched nitrogen-15, 15N is a significant factor to overcome. This is necessary due to the (relatively) high neutron capture cross-section of the far-more-common 14N, which affects the neutron economy of a react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
