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Nitridohydride
In chemistry, a hydridonitride (nitridohydride, nitride hydride, or hydride nitride) is a chemical compound that contains hydride () and nitride () ions in a single Phase (matter), phase. These inorganic compounds are distinct from inorganic Metal amides, amides and Inorganic imide, imides as the hydrogen does not share a bond with nitrogen, and contain a larger proportion of metals. Structure The hydride ion H− is stabilised by being surrounded by Electropositive, electropositive elements such as alkalis or Alkaline earth metal, alkaline earths. Quaternary compounds exist where nitrogen forms a complex with bonds to a transition or main group element. The hydride requires the presence of another alkaline earth element. Production Hydridonitrides may be produced by a process called self-propagating high-temperature synthesis (SHS) where a metal nitride is ignited in a hydrogen atmosphere. A metal (Ti, Zr, Hf, Y) can also be ignited in an atmosphere mixing hydrogen and nitrogen, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Imide
The inorganic imides are compounds containing an ion composed of nitrogen bonded to hydrogen with formula HN2−. Organic imides have the NH group, and two single or one double covalent bond to other atoms. The imides are related to the inorganic amides (H2N−), the nitrides (N3−) and the nitridohydrides (N3−•H−). In addition to solid state imides, molecular imides are also known in dilute gases, where their spectrum can be studied. Imide can be a ligand, with a double bond to a metal such as molybdenum (e.g. Mo=NH). As a ligand it is called imido. The imido ligand is part of a nitrogen fixation cycle: Mo•N2 → Mo-N=N− → Mo-N=NH (diazenido) → Mo-N=NH2+ → Mo=N-NH2 (hydrazido) → Mo=N-NH3+ (hydrazidium) → Mo≡N (nitrido) + NH3 → Mo≡NH+ → Mo=NH (imido) → Mo=NH2+ → Mo-NH2 (amido) → Mo-NH3+ → Mo•NH3 (ammine); with the oxidation state of molybdenum varying to accommodate the number bonds from nitrogen. When the hydrogen of the imide group is sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemistry
Chemistry is the scientific study of the properties and behavior of matter. It is a natural science that covers the elements that make up matter to the compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a reaction with other substances. Chemistry also addresses the nature of chemical bonds in chemical compounds. In the scope of its subject, chemistry occupies an intermediate position between physics and biology. It is sometimes called the central science because it provides a foundation for understanding both basic and applied scientific disciplines at a fundamental level. For example, chemistry explains aspects of plant growth ( botany), the formation of igneous rocks ( geology), how atmospheric ozone is formed and how environmental pollutants are degraded ( ecology), the properties of the soil on the moon ( cosmochemistry), how medications work (pharmacology), and how to collect DNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Vapor
(99.9839 °C) , - , Boiling point , , - , specific gas constant , 461.5 J/( kg·K) , - , Heat of vaporization , 2.27 MJ/kg , - , Heat capacity , 1.864 kJ/(kg·K) Water vapor, water vapour or aqueous vapor is the gaseous phase of water. It is one state of water within the hydrosphere. Water vapor can be produced from the evaporation or boiling of liquid water or from the sublimation of ice. Water vapor is transparent, like most constituents of the atmosphere. Under typical atmospheric conditions, water vapor is continuously generated by evaporation and removed by condensation. It is less dense than most of the other constituents of air and triggers convection currents that can lead to clouds. Being a component of Earth's hydrosphere and hydrologic cycle, it is particularly abundant in Earth's atmosphere, where it acts as a greenhouse gas and warming feedback, contributing more to total greenhouse effect than non-condensable gases such as carbon dio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrides
In chemistry, a nitride is an inorganic compound of nitrogen. The "nitride" anion, N3- ion, is very elusive but compounds of nitride are numerous, although rarely naturally occuring. Some nitrides have a find applications, such as wear-resistant coatings (e.g., titanium nitride, TiN), hard ceramic materials (e.g., silicon nitride, Si3N4), and semiconductors (e.g., gallium nitride, GaN). The development of GaN-based light emitting diodes was recognized by the 2014 Nobel Prize in Physics. Metal nitrido complexes are also common. Synthesis of inorganic metal nitrides is challenging because nitrogen gas (N2) is not very reactive at low temperatures, but it becomes more reactive at higher temperatures. Therefore, a balance must be achieved between the low reactivity of nitrogen gas at low temperatures and the entropy driven formation of N2 at high temperatures. However, synthetic methods for nitrides are growing more sophisticated and the materials are of increasing technolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neil Ashcroft
Neil William Ashcroft (27 November 1938 – 15 March 2021) was a British solid-state physicist. Early life and education Ashcroft was born in London on 27 November 1938, and migrated to New Zealand in 1947. He was educated at Hutt Valley High School, and completed his undergraduate studies at Victoria University College, earning a Bachelor of Science degree, in 1958. He received his PhD in 1964 from the University of Cambridge for research investigating the Fermi surfaces of metals. Career Following his PhD, Ashcroft completed postdoctoral research at the University of Chicago and at Cornell University, where he became a Professor in 1975. In 1990 he was named the Horace White Professor of Physics, and was elected to emeritus status in 2006. He served as the director for the Laboratory of Atomic and Solid State Physics at Cornell University (1979–1984), the director for the Cornell Center for Materials Research (1997–2000), and as the deputy director for the High Energy S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallic Hydrogen
Metallic hydrogen is a phase of hydrogen in which it behaves like an electrical conductor. This phase was predicted in 1935 on theoretical grounds by Eugene Wigner and Hillard Bell Huntington. At high pressure and temperatures, metallic hydrogen can exist as a partial liquid rather than a solid, and researchers think it might be present in large quantities in the hot and gravitationally compressed interiors of Jupiter and Saturn, as well as in some exoplanets. Theoretical predictions Hydrogen under pressure Though often placed at the top of the alkali metal column in the periodic table, hydrogen does not, under ordinary conditions, exhibit the properties of an alkali metal. Instead, it forms diatomic molecules, analogous to halogens and some nonmetals in the second period of the periodic table, such as nitrogen and oxygen. Diatomic hydrogen is a gas that, at atmospheric pressure, liquefies and solidifies only at very low temperature (20 degrees and 14 degrees above ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simons Foundation
The Simons Foundation is a private foundation established in 1994 by Marilyn and Jim Simons with offices in New York City New York, often called New York City or NYC, is the most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the most densely populated major city in the U .... As one of the largest charitable organizations in the US with assets of over $5 billion in 2022, the foundation's mission is to advance the frontiers of research in mathematics and the basic sciences. The foundation supports science by making grants to individual researchers and their projects. In 2021, Marilyn Simons stepped down as president after 26 years at the helm, and astrophysicist David Spergel was appointed president. The Flatiron Institute In 2016, the foundation launched the Flatiron Institute, its in-house multidisciplinary research institute focused on computational science. The Flatiron Ins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quanta Magazine
''Quanta Magazine'' is an editorially independent online publication of the Simons Foundation covering developments in physics, mathematics, biology and computer science Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to practical disciplines (includin .... ''Undark Magazine'' described ''Quanta Magazine'' as "highly regarded for its masterful coverage of complex topics in science and math." The science news aggregator ''RealClearScience'' ranked ''Quanta Magazine'' first on its list of "The Top 10 Websites for Science in 2018." In 2020, the magazine received a National Magazine Award for General Excellence from the American Society of Magazine Editors for its "willingness to tackle some of the toughest and most difficult topics in science and math in a language that is accessible to the lay reader without condes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Institute Of Electrical And Electronics Engineers
The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operations center in Piscataway, New Jersey. The mission of the IEEE is ''advancing technology for the benefit of humanity''. The IEEE was formed from the amalgamation of the American Institute of Electrical Engineers and the Institute of Radio Engineers in 1963. Due to its expansion of scope into so many related fields, it is simply referred to by the letters I-E-E-E (pronounced I-triple-E), except on legal business documents. , it is the world's largest association of technical professionals with more than 423,000 members in over 160 countries around the world. Its objectives are the educational and technical advancement of electrical and electronic engineering, telecommunications, computer engineering and similar disciplines. History Or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEEE Spectrum
''IEEE Spectrum'' is a magazine edited by the Institute of Electrical and Electronics Engineers The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operation .... The first issue of ''IEEE Spectrum'' was published in January 1964 as a successor to ''Electrical Engineering''. The magazine contains peer-reviewed articles about technology and science trends affecting business and society. In 2010, ''IEEE Spectrum'' was the recipient of '' Utne Reader'' magazine's Utne Independent Press Award for Science/Technology Coverage. In 2012, ''IEEE Spectrum'' was selected as the winner of the National Magazine Awards' "General Excellence Among Thought Leader Magazines" category. References External links * {{Official website, https://spectrum.ieee.org/ Monthly magazines published in the United Stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyhydride
A polyhydride or superhydride is a compound that contains an abnormally large amount of hydrogen. This can be described as high hydrogen stoichiometry. Examples include iron pentahydride FeH5, LiH6, and LiH7. By contrast, the more well known lithium hydride only has one hydrogen atom. Polyhydrides are only known to be stable under high pressure. Polyhydrides are important because they can form substances with a very high density of hydrogen. They may resemble the elusive metallic hydrogen, but can be made under lower pressures. One possibility is that they could be superconductors. Hydrogen sulfide under high pressures forms SH3 units, and can be a superconductor at and a pressure of 1.5 million atmospheres. Structures The polyhydrides of alkaline earth and alkali metals contain cage structures. Also hydrogen may be clustered into H−, H3−, or H2 units. Polyhydrides of transition metals may have the hydrogen atoms arranged around the metal atom. Computations suggest t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Room-temperature Superconductor
A room-temperature superconductor is a material that is capable of exhibiting superconductivity at operating temperatures above , that is, temperatures that can be reached and easily maintained in an everyday environment. , the material with the highest accepted superconducting temperature is an extremely pressurized carbonaceous sulfur hydride with a critical transition temperature of +15 °C at 267 GPa. On 22 September 2022, the original article reporting superconductivity in the carbonaceous sulfur hydride material was retracted by ''Nature'' journal editorial board due to a non standard, user-defined data analysis, calling into question the scientific validity of the claim. At atmospheric pressure the temperature record is still held by cuprates, which have demonstrated superconductivity at temperatures as high as . Although researchers once doubted whether room-temperature superconductivity was actually achievable, superconductivity has repeatedly been discovered at te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
