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Docosane
320px Higher alkanes are alkanes with a high number of carbon atoms. It is common jargon. One definition says higher alkanes are alkanes having nine or more carbon atoms. Thus, according to this definition, nonane is the lightest higher alkane. As pure substances, higher alkanes are rarely significant, but they are major components of useful lubricants and fuels. Synthesis The preparation of specific long-chain hydrocarbons typically involves manipulations of long chain precursors or the coupling of two medium-chain components. For the first case, fatty acids can be a source of higher alkanes via decarboxylation reaction. Such processes have been investigated as a route to biodiesel. Fatty acid esters and fatty acid nitriles react with long chain Grignard reagents to give, after suitable workup, long-chain ketones. The Wolff-Kishner Reaction provides a way to remove the ketone functionality, giving long-chain hydrocarbons. Even-numbered, long-chain hydrocarbons can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetracosane Structure
Tetracosane, also called ''tetrakosane'', is an alkane hydrocarbon with the structural formula H(CH2)24H. As with other alkanes, its name is derived from Greek for the number of carbon atoms, 24, in the molecule. It has 14,490,245 constitutional isomers, and 252,260,276 stereoisomers. ''n''-Tetracosane is found in mineral form, called evenkite, in the Evenkiysky District, Evenki Region on Lower Tunguska River in Siberia and the Bucnik quarry near Konma in eastern Moravia, Czech Republic. Evenkite is found as colourless flakes and is reported to fluoresce yellow-orange. See also * List of alkanes References External linksNIST Entry Alkanes {{Hydrocarbon-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ladybird
Coccinellidae () is a widespread family of small beetles. They are commonly known as ladybugs in North America and ladybirds in the United Kingdom; "lady" refers to mother Mary. Entomologists use the names ladybird beetles or lady beetles to avoid confusion with true bugs. The more than 6,000 described species have a global distribution and are found in a variety of habitats. They are oval beetles with a domed back and flat underside. Many of the species have conspicuous aposematic (warning) colours and patterns, such as red with black spots, that warn potential predators that they taste bad. Most coccinellid species are carnivorous predators, preying on insects such as aphids and scale insects. Other species are known to consume non-animal matter, including plants and fungi. They are promiscuous breeders, reproducing in spring and summer in temperate regions and during the wet season in tropical regions. Many predatory species lay their eggs near colonies of prey, providi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetane Number
Cetane number (cetane rating) (CN) is an indicator of the combustion speed of diesel fuel and compression needed for ignition. It plays a similar role for diesel as octane rating does for gasoline. The CN is an important factor in determining the quality of diesel fuel, but not the only one; other measurements of diesel fuel's quality include (but are not limited to) energy content, density, lubricity, cold-flow properties and sulfur content.Werner Dabelstein, Arno Reglitzky, Andrea Schütze and Klaus Reders "Automotive Fuels" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2007, Wiley-VCH, Weinheim. Definition The cetane number of a fuel is defined by finding a blend of cetane and isocetane with the same ignition delay. Cetane has a cetane number defined to be 100, while isocetane's measured cetane number is 15, replacing the former reference fuel alpha-methylnaphthalene, which was assigned a cetane number of 0. Once the blend is known, the cetane number is calculat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aviation Fuel
Aviation fuels are either petroleum-based or blends of petroleum and synthetic fuels, used to power aircraft. They have more stringent requirements than fuels used for ground applications, such as heating and road transport, and they contain additives to enhance or preserve properties important to fuel performance and handling. They are kerosene-based fuels (such as JP-8 and Jet A-1) used in gas-turbine-powered aircraft. Piston-engined aircraft use leaded gasoline, while those with diesel engines may use jet fuel (kerosene). By 2012, all U.S. Air Force aircraft had been certified to use a 50-50 blend of kerosene and synthetic fuel derived from coal or natural gas, in an effort to stabilize fuel costs. Types of aviation fuel Conventional aviation fuels Jet fuel Jet fuel is a clear to straw-colored fuel, based on either an unleaded kerosene (Jet A-1), or a naphtha–kerosene blend (Jet B). Similar to diesel fuel, it can be used in either Diesel engine, compression ignition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerosene
Kerosene, or paraffin, is a combustibility, combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in Aviation fuel, aviation as well as households. Its name derives from the Greek (''kērós'') meaning "wax"; it was registered as a trademark by Nova Scotian, Nova Scotia geologist and inventor Abraham Pineo Gesner, Abraham Gesner in 1854 before evolving into a generic trademark. It is sometimes spelled kerosine in scientific and industrial usage. Kerosene is widely used to power jet engines of aircraft (jet fuel), as well as some rocket engines in a highly refined form called RP-1. It is also commonly used as a cooking and lighting fuel, and for fire toys such as Poi (performance art)#Fire poi, poi. In parts of Asia, kerosene is sometimes used as fuel for small outboard motors or even motorcycles. World total kerosene consumption for all purposes is equivalent to about 5,500,000 barrels per day as of July 2023. The term "kerosene" is comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diesel Fuel
Diesel fuel, also called diesel oil, heavy oil (historically) or simply diesel, is any liquid fuel specifically designed for use in a diesel engine, a type of internal combustion engine in which fuel ignition takes place without a spark as a result of compression of the inlet air and then injection of fuel. Therefore, diesel fuel needs good compression ignition characteristics. The most common type of diesel fuel is a specific fractional distillation, fractional distillate of petroleum fuel oil, but alternatives that are not derived from petroleum, such as biodiesel, biomass to liquid (BTL) or gas to liquid (GTL) diesel are increasingly being developed and adopted. To distinguish these types, petroleum-derived diesel is sometimes called petrodiesel in some academic circles. Diesel is a high-volume product of oil refineries. In many countries, diesel fuel is standardized. For example, in the European Union, the standard for diesel fuel is EN 590. Ultra-low-sulfur diesel (ULSD) i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gasoline
Gasoline ( North American English) or petrol ( Commonwealth English) is a petrochemical product characterized as a transparent, yellowish, and flammable liquid normally used as a fuel for spark-ignited internal combustion engines. When formulated as a fuel for engines, gasoline is chemically composed of organic compounds derived from the fractional distillation of petroleum and later chemically enhanced with gasoline additives. It is a high-volume profitable product produced in crude oil refineries. The ability of a particular gasoline blend to resist premature ignition (which causes knocking and reduces efficiency in reciprocating engines) is measured by its octane rating. Tetraethyl lead was once widely used to increase the octane rating but is not used in modern automotive gasoline due to the health hazard. Aviation, off-road motor vehicles, and racing car engines still use leaded gasolines. Other substances are frequently added to gasoline to improve chemical st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscosity
Viscosity is a measure of a fluid's rate-dependent drag (physics), resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for example, syrup has a higher viscosity than water. Viscosity is defined scientifically as a force multiplied by a time divided by an area. Thus its SI units are newton-seconds per metre squared, or pascal-seconds. Viscosity quantifies the internal friction, frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's center line than near its walls. Experiments show that some stress (physics), stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexadecane
Hexadecane (also called cetane) is an alkane hydrocarbon with the chemical formula C16H34. Hexadecane consists of a chain of 16 carbon atoms, with three hydrogen atoms bonded to the two end carbon atoms, and two hydrogens bonded to each of the 14 other carbon atoms. Isohexadecane is a branch chained isomer of hexadecane.https://b4brands.com/resources/ingredient-directory/isohexadecane/#:~:text=Isohexadecane%20is%20a%20branched%2Dchain,that%20is%20found%20in%20petroleum. Cetane number ''Cetane'' is often used as a shorthand for cetane number, a measure of the combustion of diesel fuel. Cetane ignites very easily under compression; for this reason, it is assigned a cetane number of 100, and serves as a reference for other fuel mixtures. Hexadecyl radical Hexadecyl, or cetyl, is an alkyl radical of carbon and hydrogen derived from hexadecane, with formula C16H33 and with mass 225.433, occurring especially in cetyl alcohol. It confers strong hydrophobicity on molecules containi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalysts
Catalysis () is the increase in reaction rate, rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form reaction intermediate, intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. The rate increase occurs because the catalyst allows the reaction to occur by an alternative mechanism which may be much faster than the noncatalyzed mechanism. However the noncatalyzed mechanism does remain possible, so that the total rate (catalyzed plus noncatalyzed) can only increase in the presence of the catalyst and never decrease. Catalysis may be classified as either homogeneous catalysis, homogeneou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cracking
Cracking may refer to: * Cracking, the formation of a fracture or partial fracture in a solid material studied as fracture mechanics ** Performing a sternotomy * Fluid catalytic cracking, a catalytic process widely used in oil refineries for cracking large hydrocarbon molecules into smaller molecules * Cracking (chemistry), the decomposition of complex organic molecules into smaller ones * Cracking joints, the practice of manipulating one's bone joints to make a sharp sound * Cracking codes, see cryptanalysis * Whip cracking * Safe cracking * ''Crackin, band featuring Lester Abrams * Packing and cracking, a method of creating voting districts to give a political party an advantage In computing: * Another name for security hacking; the practice of defeating computer security. * Password cracking, the process of discovering the plaintext of an encrypted computer password. * Software cracking, the defeating of software copy protection. See also * Crack (other) *Cracker ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
