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Transatomic Power
Transatomic Power was an American company that designed Generation IV nuclear reactors based on molten salt reactor (MSR) technology. MIT alumni Dr. Leslie Dewan and Mark Massie founded Transatomic Power in 2011, and its board directors included E Ink Corporation co-founder Russ Wilcox. Among its backers were the venture capital outfit Founders Fund, of which Peter Thiel is a partner. In 2013, the U.S. Department of Energy awarded Transatomic first prize in the ARPA-E Future Energy innovation contest. In 2018 the company announced that it would be winding down and open source its intellectual property. The company discovered that in 2016 it had made errors in its early analysis and realized that the design couldn't consume nuclear waste. Transatomic Power ceased operation on September 25, 2018. Reactor concept Transatomic initial concept was that of a ''Waste Annihilating Molten Salt Reactor'' (WAMSR) designed to digest spent nuclear fuel. The concept was based on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Privately Held 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] |
Spent Nuclear Fuel
Spent nuclear fuel, occasionally called used nuclear fuel, is nuclear fuel that has been irradiated in a nuclear reactor (usually at a nuclear power plant). It is no longer useful in sustaining a nuclear reaction in an ordinary thermal reactor and depending on its point along the nuclear fuel cycle, it may have considerably different isotopic constituents. The term "fuel" is slightly confusing, as it implies a combustion of some type, which does not occur in a nuclear power plant. Nevertheless, this term is generally accepted. Nature of spent fuel Nanomaterial properties In the oxide fuel, intense temperature gradients exist that cause fission products to migrate. The zirconium tends to move to the centre of the fuel pellet where the temperature is highest, while the lower-boiling fission products move to the edge of the pellet. The pellet is likely to contain many small bubble-like pores that form during use; the fission product xenon migrates to these voids. Some of this xeno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beryllium Fluoride
Beryllium fluoride is the inorganic compound with the chemical formula, formula Beryllium, BeFluorine, F2. This white solid is the principal precursor for the manufacture of beryllium metal. Its structure resembles that of quartz, but BeF2 is highly soluble in water. Properties Beryllium fluoride has distinctive optical properties. In the form of fluoroberyllate glass it has the lowest refractive index for a solid at room temperature of 1.275. Its dispersive power is the lowest for a solid at 0.0093, and the nonlinear coefficient is also the lowest at 2 × 10−14. Structure and bonding The structure of solid BeF2 resembles that of cristobalite. Be2+ centers are four coordinate and tetrahedral and the fluoride centers are two-coordinate. The Be-F bond lengths are about 1.54 Å. Analogous to silicon dioxide, SiO2, BeF2 can also adopt a number of related structures. An analogy also exists between BeF2 and AlF3: both adopt extended structures at mild temperature. Gas and liquid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithium Fluoride
Lithium fluoride is an inorganic compound with the chemical formula LiF. It is a colorless solid, that transitions to white with decreasing crystal size. Although odorless, lithium fluoride has a bitter-saline taste. Its structure is analogous to that of sodium chloride, but it is much less soluble in water. It is mainly used as a component of molten salts. Formation of LiF from the elements releases one of the highest energy per mass of reactants, second only to that of BeO. Manufacturing LiF is prepared from lithium hydroxide or lithium carbonate with hydrogen fluoride. Applications Precursor to LiPF6 for batteries Lithium fluoride is reacted with hydrogen fluoride (HF) and phosphorus pentachloride to make lithium hexafluorophosphate, an ingredient in lithium ion battery electrolyte. In molten salts Fluorine is produced by the electrolysis of molten potassium bifluoride. This electrolysis proceeds more efficiently when the electrolyte contains a few percent of LiF, possibly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Rods
Control rods are used in nuclear reactors to control the rate of fission of the nuclear fuel – uranium or plutonium. Their compositions include chemical elements such as boron, cadmium, silver, hafnium, or indium, that are capable of absorbing many neutrons without themselves decaying. These elements have different neutron capture cross sections for neutrons of various energies. Boiling water reactors (BWR), pressurized water reactors (PWR), and heavy-water reactors (HWR) operate with thermal neutrons, while breeder reactors operate with fast neutrons. Each reactor design can use different control rod materials based on the energy spectrum of its neutrons. Control rods have been used in nuclear aircraft engines like Project Pluto as a method of control. Operating principle Control rods are inserted into the core of a nuclear reactor and adjusted in order to control the rate of the nuclear chain reaction and, thereby, the thermal power output of the reactor, the rate of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fail Safe
In engineering, a fail-safe is a design feature or practice that in the event of a specific type of failure, inherently responds in a way that will cause minimal or no harm to other equipment, to the environment or to people. Unlike inherent safety to a particular hazard, a system being "fail-safe" does not mean that failure is impossible or improbable, but rather that the system's design prevents or mitigates unsafe consequences of the system's failure. That is, if and when a "fail-safe" system fails, it remains at least as safe as it was before the failure. Since many types of failure are possible, failure mode and effects analysis is used to examine failure situations and recommend safety design and procedures. Some systems can never be made fail-safe, as continuous availability is needed. Redundancy, fault tolerance, or contingency plans are used for these situations (e.g. multiple independently controlled and fuel-fed engines). Examples Mechanical or physical Examples incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Passive Nuclear Safety
Passive nuclear safety is a design approach for safety features, implemented in a nuclear reactor, that does not require any active intervention on the part of the operator or electrical/electronic feedback in order to bring the reactor to a safe shutdown state, in the event of a particular type of emergency (usually overheating resulting from a loss of coolant or loss of coolant flow). Such design features tend to rely on the engineering of components such that their predicted behaviour would slow down, rather than accelerate the deterioration of the reactor state; they typically take advantage of natural forces or phenomena such as gravity, buoyancy, pressure differences, conduction or natural heat convection to accomplish safety functions without requiring an active power source. Many older common reactor designs use passive safety systems to a limited extent, rather, relying on active safety systems such as diesel powered motors. Some newer reactor designs feature more passive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megawatt Thermal
The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer. The watt is named after James Watt (1736–1819), an 18th-century Scottish inventor, mechanical engineer, and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution. Overview When an object's velocity is held constant at one metre per second against a constant opposing force of one newton, the rate at which work is done is one watt. : \mathrm In terms of electromagnetism, one watt is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). : \mathrm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Alvin Weinberg Foundation
The Alvin Weinberg Foundation was a registered UK charity, operating under the name Weinberg Next Nuclear, that campaigned for research and development into next-generation nuclear energy. In particular, it advocated advancement of Liquid Fluoride Thorium Reactor (LFTR) and other Molten Salt Reactor (MSR) technologies. It was named for Dr Alvin M. Weinberg, Director of Oak Ridge National Laboratory between 1955–1973 and the main advocate of MSR development. History * September 2011: Launched at House of Lords. * January 2014: Becomes a Registered Charity in England and Wales. * May 2015: Stephen Tindale joins as Director. * July 2017: The Weinberg Foundation dissolved. People * Baroness Worthington is trustee and patron. * Stephen Tindale, who led Greenpeace in the UK from 2000 until 2005, was its last Director. See also * Thorium-based nuclear power * Generation IV reactor * Molten salt reactor * Liquid fluoride thorium reactor The liquid fluoride thorium reactor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranium
Uranium is a chemical element with the 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 is weakly radioactive because all isotopes of uranium are unstable; the half-lives of its naturally occurring isotopes range between 159,200 years and 4.5 billion years. 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 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 million in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite. In nature, uranium is found as uranium-238 (99. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thorium-based Nuclear Power
Thorium-based nuclear power generation is fueled primarily by the nuclear fission of the isotope uranium-233 produced from the fertile element thorium. A thorium fuel cycle can offer several potential advantages over a uranium fuel cycleA nuclear reactor consumes certain specific fissile isotopes to produce energy. Currently, the most common types of nuclear reactor fuel are: * Uranium-235, purified (i.e. " enriched") by reducing the amount of uranium-238 in natural mined uranium. Most nuclear power has been generated using low-enriched uranium (LEU), whereas high-enriched uranium (HEU) is necessary for weapons. * Plutonium-239, transmuted from uranium-238 obtained from natural mined uranium.—including the much greater abundance of thorium found on Earth, superior physical and nuclear fuel properties, and reduced nuclear waste production. One advantage of thorium fuel is its low weaponization potential; it is difficult to weaponize the uranium-233/ 232 and plutonium-238 isoto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oak Ridge National Laboratory
Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research and development center (FFRDC) under a contract with the DOE, located in Oak Ridge, Tennessee. Established in 1943, ORNL is the largest science and energy national laboratory in the Department of Energy system (by size) and third largest by annual budget. It is located in the Roane County section of Oak Ridge, Tennessee. Its scientific programs focus on materials, nuclear science, neutron science, energy, high-performance computing, systems biology and national security, sometimes in partnership with the state of Tennessee, universities and other industries. ORNL has several of the world's top supercomputers, including Frontier, ranked by the TOP500 as the world's most powerful. The lab is a leading neutron and nuclear power research f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
