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Higher Alkanes
Higher alkanes are alkanes having nine or more carbon atoms. Nonane is the lightest alkane to have a flash point above 25 °C, and is not classified as dangerously flammable. The term ''higher alkanes'' is sometimes used literally as "alkanes with a higher number of carbon atoms". One definition distinguishes the higher alkanes as the n-alkanes that are solid under natural conditions. Uses Alkanes from nonane to hexadecane (those alkanes with nine to sixteen carbon atoms) are liquids of higher viscosity, which are less suitable for use in gasoline. They form instead the major part of diesel and aviation fuel. Diesel fuels are characterised by their cetane number, cetane being an older name for hexadecane. However the higher melting points of these alkanes can cause problems at low temperatures and in polar regions, where the fuel becomes too thick to flow correctly. Mixtures of the normal alkanes are used as boiling point standards for simulated distillation by gas chroma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkane
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in which all the carbon–carbon bonds are single. Alkanes have the general chemical formula . The alkanes range in complexity from the simplest case of methane (), where ''n'' = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like pentacontane () or 6-ethyl-2-methyl-5-(1-methylethyl) octane, an isomer of tetradecane (). The International Union of Pure and Applied Chemistry (IUPAC) defines alkanes as "acyclic branched or unbranched hydrocarbons having the general formula , and therefore consisting entirely of hydrogen atoms and saturated carbon atoms". However, some sources use the term to denote ''any'' saturated hydrocarbon, including those that are either monocyclic (i.e. the cycloalkanes) or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lubricant
A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, transporting foreign particles, or heating or cooling the surfaces. The property of reducing friction is known as lubricity. In addition to industrial applications, lubricants are used for many other purposes. Other uses include cooking (oils and fats in use in frying pans, in baking to prevent food sticking), bioapplications on humans (e.g. lubricants for artificial joints), ultrasound examination, medical examination, and sexual intercourse. It is mainly used to reduce friction and to contribute to a better and efficient functioning of a mechanism. History Lubricants have been in some use for thousands of years. Calcium soaps have been identified on the axles of chariots dated to 1400 BC. Building stones were slid on oil-impregrated lumb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tridecane
Tridecane or ''n''-tridecane is an alkane with the chemical formula CH3(CH2)11CH3. Tridecane is a combustible colourless liquid. In industry, they have no specific value aside from being components of various fuels and solvents. In the research laboratory, tridecane is also used as a distillation chaser. Natural occurrence Nymphs of the southern green shield bug produce tridecane as a dispersion/aggregation pheromone, which possibly serves as a defense against predators. It is also the main component of the defensive fluid produced by the stink bug ''Cosmopepla bimaculata''. See also * Higher alkanes * List of isomers of tridecane This is the list of the 802 isomers of tridecane, with their IUPAC names. Straight Chain * Tridecane With dodecane backbone * 2-Methyldodecane * 3-Methyldodecane * 4-Methyldodecane * 5-Methyldodecane * 6-Methyldodecane With undecane backbone D ... References External links Material Safety Data Sheet for TridecanePhytochemical and Ethnobota ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dodecane
Dodecane (also known as dihexyl, bihexyl, adakane 12, or duodecane) is an oily liquid ''n''-alkane hydrocarbon with the chemical formula C12H26 (which has 355 isomers). It is used as a solvent, distillation chaser, and scintillator component. It is used as a diluent for tributyl phosphate (TBP) in nuclear reprocessing plants. Combustion reaction The combustion reaction of dodecane is as follows: :2 C12H26(''l'') + 37 O2(''g'') → 24 CO2(''g'') + 26 H2O(''g'') : Δ''H''° = −7513 kJ One litre of fuel needs about 15 kg of air to burn, and generates 2.3 kg (or 1.2 m3) of CO2 upon complete combustion. Jet fuel surrogate In recent years, ''n''-dodecane has garnered attention as a possible surrogate for kerosene-based fuels such as Jet-A, S-8, and other conventional aviation fuels. It is considered a second-generation fuel surrogate designed to emulate the laminar flame speed, largely supplanting ''n''-decane, primarily due to its higher molecular mass and l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Undecane
Undecane (also known as hendecane) is a liquid alkane hydrocarbon with the chemical formula CH3(CH2)9CH3. It is used as a mild sex attractant for various types of moths and cockroaches, and an alert signal for a variety of ants.Hölldobler B, Wilson EO (1990). ''The Ants''. Harvard University Press. , p. 287 It has 159 isomers. Undecane may also be used as an internal standard in gas chromatography when working with other hydrocarbons. Since the boiling point of undecane (196 °C) is well known, it may be used as a comparison for retention times in a gas chromatograph for molecules whose structure has been freshly elucidated. For example, if one is working with a 50 m crosslinked methyl silicone capillary column with an oven temperature increasing slowly, beginning around 60 °C, an 11-carbon molecule like undecane may be used as an internal standard to be compared with the retention times of other 10-, 11-, or 12- carbon molecules, depending on their structures. Se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decane
Decane is an alkane hydrocarbon with the chemical formula C10H22. Although 75 structural isomers are possible for decane, the term usually refers to the normal-decane ("''n''-decane"), with the formula CH3(CH2)8CH3. All isomers, however, exhibit similar properties and little attention is paid to the composition. These isomers are flammable liquids. Decane is present in small quantities (less than 1%) in gasoline (petrol) and kerosene. Like other alkanes, it is a nonpolar solvent, and does not dissolve in water, and is readily combustible. Although it is a component of fuels, it is of little importance as a chemical feedstock, unlike a handful of other alkanes. Reactions Decane undergoes combustion, just like other alkanes. In the presence of sufficient oxygen, it burns to form water and carbon dioxide. :2 C10H22 + 31 O2 → 20 CO2 + 22 H2O With insufficient oxygen, carbon monoxide is also formed. Other It has a surface tension of 0.0238 N·m−1.Website of Krüss'' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluid Catalytic Cracking
Fluid Catalytic Cracking (FCC) is the conversion process used in petroleum refineries to convert the high-boiling point, high-molecular weight hydrocarbon fractions of petroleum (crude oils) into gasoline, olefinic gases, and other petroleum products. The cracking of petroleum hydrocarbons was originally done by thermal cracking, now virtually replaced by catalytic cracking, which yields greater volumes of high octane rating gasoline; and produces by-product gases, with more carbon-carbon double bonds (i.e. olefins), that are of greater economic value than the gases produced by thermal cracking. The feedstock to the FCC conversion process usually is heavy gas oil (HGO), which is that portion of the petroleum (crude oil) that has an initial boiling-point temperature of or higher, at atmospheric pressure, and that has an average molecular weight that ranges from about 200 to 600 or higher; heavy gas oil also is known as “heavy vacuum gas oil” (HVGO). In the fluid catalytic cra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitumen
Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used. Full text at Internet Archive (archive.org) The word is derived from the Ancient Greek ἄσφαλτος ''ásphaltos''. The largest natural deposit of asphalt in the world, estimated to contain 10 million tons, is the Pitch Lake located in La Brea in southwest Trinidad (Antilles island located on the northeastern coast of Venezuela), within the Siparia Regional Corporation. The primary use (70%) of asphalt is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs. In material sciences and engineering, the terms "asphalt" an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are fatty acid esters of glycerol; they are important in biology, being one of the main classes of lipids and comprising the bulk of animal fats and vegetable oils. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. They perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties. '' Nomenclature Etymology Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beeswax
Beeswax (''cera alba'') is a natural wax produced by honey bees of the genus ''Apis''. The wax is formed into scales by eight wax-producing glands in the abdominal segments of worker bees, which discard it in or at the hive. The hive workers collect and use it to form cells for honey storage and larval and pupal protection within the beehive. Chemically, beeswax consists mainly of esters of fatty acids and various long-chain alcohols. Beeswax has been used since prehistory as the first plastic, as a lubricant and waterproofing agent, in lost wax casting of metals and glass, as a polish for wood and leather, for making candles, as an ingredient in cosmetics and as an artistic medium in encaustic painting. Beeswax is edible, having similarly negligible toxicity to plant waxes, and is approved for food use in most countries and in the European Union under the E number E901. Production The beeswax is formed by worker bees, which secrete it from eight wax-producing mirror glan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Candle
A candle is an ignitable wick embedded in wax, or another flammable solid substance such as tallow, that provides light, and in some cases, a fragrance. A candle can also provide heat or a method of keeping time. A person who makes candles is traditionally known as a chandler. Various devices have been invented to hold candles, from simple tabletop candlesticks, also known as candle holders, to elaborate candelabra and chandeliers. For a candle to burn, a heat source (commonly a naked flame from a match or lighter) is used to light the candle's wick, which melts and vaporizes a small amount of fuel (the wax). Once vaporized, the fuel combines with oxygen in the atmosphere to ignite and form a constant flame. This flame provides sufficient heat to keep the candle burning via a self-sustaining chain of events: the heat of the flame melts the top of the mass of solid fuel; the liquefied fuel then moves upward through the wick via capillary action; the liquefied fuel finally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Insulation
An electrical insulator is a material in which electric current does not flow freely. The atoms of the insulator have tightly bound electrons which cannot readily move. Other materials—semiconductors and conductors—conduct electric current more easily. The property that distinguishes an insulator is its resistivity; insulators have higher resistivity than semiconductors or conductors. The most common examples are non-metals. A perfect insulator does not exist because even insulators contain small numbers of mobile charges ( charge carriers) which can carry current. In addition, all insulators become electrically conductive when a sufficiently large voltage is applied that the electric field tears electrons away from the atoms. This is known as the breakdown voltage of an insulator. Some materials such as glass, paper and PTFE, which have high resistivity, are very good electrical insulators. A much larger class of materials, even though they may have lower bulk resistivit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
