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Ice XV
Ice XV is a crystalline form of ice, the proton-ordered form of ice VI. It is created by cooling hydrochloric-acid-doped water to around 130 K at 1 GPa (9820 atm). Ordinary water ice is known as ice Ih, (in the Bridgman nomenclature). Different types of ice, from ice II to ice XVI, have been created in the laboratory at different temperatures and pressures. On 14 June 2009, Christoph Salzmann at the University of Oxford and colleagues reported having created ice XV and say that its properties differ significantly from those predicted. In particular, ice XV is antiferroelectric rather than ferroelectric Ferroelectricity is a characteristic of certain materials that have a spontaneous electric polarization that can be reversed by the application of an external electric field. All ferroelectrics are also piezoelectric and pyroelectric, with the add ... as had been predicted. References * Water ice {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice VI
Ice VI is a form of ice that exists at high pressure at the order of about 1 GPa (= 10 000 bar) and temperatures ranging from 130 up to 355 Kelvin (−143 °C up to 82 °C); see also the phase diagram of water. Its discovery and the discovery of other high-pressure forms of water were published by P.W. Bridgman in January 1912. It is part of one of the inner layers of Titan. Properties Ice VI has a density of 1.31 g/cm3 and a tetragonal crystal system with the space group P42/nmc; its unit cell contains 10 water molecules and has the dimensions a=6.27 Å and c=5.79 Å. The triple point of ''ice VI'' with ice VII and liquid water is at about 82 °C and 2.22 GPa and its triple point with ice V and liquid water is at 0.16 °C and 0.6324 GPa = 6324 bar. www1.lsbu.ac.uk, version of 9 September 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kelvin
The kelvin, symbol K, is the primary unit of temperature in the International System of Units (SI), used alongside its prefixed forms and the degree Celsius. It is named after the Belfast-born and University of Glasgow-based engineer and physicist William Thomson, 1st Baron Kelvin (1824–1907). The Kelvin scale is an absolute thermodynamic temperature scale, meaning it uses absolute zero as its null (zero) point. Historically, the Kelvin scale was developed by shifting the starting point of the much-older Celsius scale down from the melting point of water to absolute zero, and its increments still closely approximate the historic definition of a degree Celsius, but since 2019 the scale has been defined by fixing the Boltzmann constant to be exactly . Hence, one kelvin is equal to a change in the thermodynamic temperature that results in a change of thermal energy by . The temperature in degree Celsius is now defined as the temperature in kelvins minus 273.15, meaning t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pascal (unit)
The pascal (symbol: Pa) is the unit of pressure in the International System of Units (SI), and is also used to quantify internal pressure, stress, Young's modulus, and ultimate tensile strength. The unit, named after Blaise Pascal, is defined as one newton per square metre and is equivalent to 10 barye (Ba) in the CGS system. The unit of measurement called standard atmosphere (atm) is defined as 101,325 Pa. Common multiple units of the pascal are the hectopascal (1 hPa = 100 Pa), which is equal to one millibar, and the kilopascal (1 kPa = 1000 Pa), which is equal to one centibar. Meteorological observations typically report atmospheric pressure in hectopascals per the recommendation of the World Meteorological Organization, thus a standard atmosphere (atm) or typical sea-level air pressure is about 1013 hPa. Reports in the United States typically use inches of mercury or millibars (hectopascals). In Canada these reports are given in kilopascal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmosphere (unit)
The standard atmosphere (symbol: atm) is a unit of pressure defined as Pa. It is sometimes used as a ''reference pressure'' or ''standard pressure''. It is approximately equal to Earth's average atmospheric pressure at sea level. History The standard atmosphere was originally defined as the pressure exerted by 760 mm of mercury at and standard gravity (''g''n = ). It was used as a reference condition for physical and chemical properties, and was implicit in the definition of the Celsius temperature scale, which defined as the boiling point of water at this pressure. In 1954, the 10th General Conference on Weights and Measures (CGPM) adopted ''standard atmosphere'' for general use and affirmed its definition of being precisely equal to dynes per square centimetre (). This defined both temperature and pressure independent of the properties of particular substance. In addition, the CGPM noted that there had been some misapprehension that it "led some physicists to believe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wired (magazine)
''Wired'' (stylized as ''WIRED'') is a monthly American magazine, published in print and online editions, that focuses on how emerging technologies affect culture, the economy, and politics. Owned by Condé Nast, it is headquartered in San Francisco, California, and has been in publication since March/April 1993. Several spin-offs have been launched, including '' Wired UK'', ''Wired Italia'', ''Wired Japan'', and ''Wired Germany''. From its beginning, the strongest influence on the magazine's editorial outlook came from founding editor and publisher Louis Rossetto. With founding creative director John Plunkett, Rossetto in 1991 assembled a 12-page prototype, nearly all of whose ideas were realized in the magazine's first several issues. In its earliest colophons, ''Wired'' credited Canadian media theorist Marshall McLuhan as its "patron saint". ''Wired'' went on to chronicle the evolution of digital technology and its impact on society. ''Wired'' quickly became recognized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condé Nast Publications
Condé is a French place name and personal name. It is ultimately derived from a Celtic word, "Condate", meaning "confluence" (of two rivers) - from which was derived the Romanised form "Condatum", in use during the Roman period, and thence to the French "Condé" found at various locations. It may refer to: People with this surname *Alpha Condé (born 1938), Guinean politician * J. M. Condé, early 20th century illustrator *Maryse Condé (born 1937), Guadeloupean author *Miguel Condé (born 1939), Mexican painter *Sékou Condé (born 1993), Guinean footballer People with this first name * Condé Montrose Nast, American publisher Places *Château de Condé, a private estate in Condé-en-Brie, Aisne, France Places in France that contain the element ''Condé'' * Condé, Indre, in the Indre ''département'' *Condé-en-Brie, in the Aisne ''département'' *Condé-Folie, in the Somme ''département'' * Condé-lès-Autry, in the Ardennes ''département'' * Condé-lès-Herpy, in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Ih
Photograph showing details of an ice cube under magnification. Ice Ih is the form of ice commonly seen on Earth. Phase space of ice Ih with respect to other ice phases. Ice Ih (hexagonal ice crystal) (pronounced: ice one h, also known as ice-phase-one) is the hexagonal crystal form of ordinary ice, or frozen water. Virtually all ice in the biosphere is ice Ih, with the exception only of a small amount of ice Ic that is occasionally present in the upper atmosphere. Ice Ih exhibits many peculiar properties that are relevant to the existence of life and regulation of global climate. For a description of these properties, see ''Ice'', which deals primarily with ice Ih. The crystal structure is characterized by the oxygen atoms forming hexagonal symmetry with near tetrahedral bonding angles. Ice Ih is stable down to , as evidenced by x-ray diffraction and extremely high resolution thermal expansion measurements. Ice Ih is also stable under applied pressures of up to about where i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Percy Williams Bridgman
Percy Williams Bridgman (April 21, 1882 – August 20, 1961) was an American physicist who received the 1946 Nobel Prize in Physics for his work on the physics of high pressures. He also wrote extensively on the scientific method and on other aspects of the philosophy of science. The Bridgman effect, the Bridgman–Stockbarger technique, and the high-pressure mineral bridgmanite are named after him. Biography Early life Bridgman was born in Cambridge, Massachusetts, and grew up in nearby Auburndale. Bridgman's parents were both born in New England. His father, Raymond Landon Bridgman, was "profoundly religious and idealistic" and worked as a newspaper reporter assigned to state politics. His mother, Mary Ann Maria Williams, was described as "more conventional, sprightly, and competitive". Bridgman attended both elementary and high school in Auburndale, where he excelled at competitions in the classroom, on the playground, and while playing chess. Described as both shy and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice II
Ice II is a rhombohedral crystalline form of ice with a highly ordered structure. It is formed from ice Ih by compressing it at a temperature of 198 K at 300 MPa or by decompressing ice V. When heated it undergoes transformation to ice III. Ordinary water ice is known as ice Ih, (in the Bridgman nomenclature). Different types of ice, from ice II to ice XIX, have been created in the laboratory at different temperatures and pressures. It is thought that the cores of icy moons like Jupiter's Ganymede may be made of ice II. History The properties of ice II were first described and recorded by Gustav Heinrich Johann Apollon Tammann in 1900 during his experiments with ice under high pressure and low temperatures. Having produced ice III, Tammann then tried condensing the ice at a temperature between under of pressure. Tammann noted that in this state ice II was denser than he had observed ice III to be. He also found that both types of ice can be kept at normal atmospheric pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiferroelectricity
Antiferroelectricity is a physical property of certain materials. It is closely related to ferroelectricity; the relation between antiferroelectricity and ferroelectricity is analogous to the relation between antiferromagnetism and ferromagnetism. An antiferroelectric material consists of an ordered (crystalline) array of electric dipoles (from the ions and electrons in the material), but with adjacent dipoles oriented in opposite (antiparallel) directions (the dipoles of each orientation form interpenetrating sublattices, loosely analogous to a checkerboard pattern). This can be contrasted with a ferroelectric, in which the dipoles all point in the same direction. In an antiferroelectric, unlike a ferroelectric, the total, macroscopic spontaneous polarization is zero, since the adjacent dipoles cancel each other out. Antiferroelectricity is a property of a material, and it can appear or disappear (more generally, strengthen or weaken) depending on temperature, pressure, external ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferroelectricity
Ferroelectricity is a characteristic of certain materials that have a spontaneous electric polarization that can be reversed by the application of an external electric field. All ferroelectrics are also piezoelectric and pyroelectric, with the additional property that their natural electrical polarization is reversible. The term is used in analogy to ferromagnetism, in which a material exhibits a permanent magnetic moment. Ferromagnetism was already known when ferroelectricity was discovered in 1920 in Rochelle salt by Joseph Valasek.See and Thus, the prefix ''ferro'', meaning iron, was used to describe the property despite the fact that most ferroelectric materials do not contain iron. Materials that are both ferroelectric ''and'' ferromagnetic are known as multiferroics. Polarization When most materials are electrically polarized, the polarization induced, ''P'', is almost exactly proportional to the applied external electric field ''E''; so the polarization is a linear fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
