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Peters Four-step Chemistry
Peters four-step chemistry is a systematically reduced mechanism for methane combustion, named after Norbert Peters, who derived it in 1985. The mechanism reads as :\begin & \text && \ce \\ & \text && \ce \\ & \text && \ce \\ & \text && \ce \end The mechanism predicted four different regimes where each reaction takes place. The third reaction, known as radical consumption layer, where most of the heat is released, and the first reaction, also known as fuel consumption layer, occur in a narrow region at the flame. The fourth reaction is the hydrogen oxidation layer, whose thickness is much larger than the former two layers. Finally, the carbon monoxide oxidation layer is the largest of them all, corresponding to the second reaction, and oxidizes very slowly. Peters-Williams three-step chemistry A three-step mechanism was derived in 1987 by Peters and Forman A. Williams by assuming steady-state approximation for the hydrogen radical. Then, :\begin & \text && \ce \\ & \text ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it poses technical challenges due to its gaseous state under normal conditions for temperature and pressure. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the atmosphere, it is known as atmospheric methane. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases. It has also been detected on other plane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norbert Peters (engineer)
Norbert Peters (10 July 1942 – 4 July 2015) was a professor at RWTH Aachen University, Germany and one of the world-wide authorities in the field of combustion engineering. He headed the '' Institut für Technische Verbrennung ''(Institute for Combustion Technology). Born in Linz, Austria, he was educated at the Karlsruhe University of Technology and later at the Technical University of Berlin. He worked in Rourkela Steel Plant for six months. Peters's primary research interest was in the field of combustion engineering, especially turbulent flames. The interaction between turbulence and combustion constituted an important part of his research. He was author of the book titled ''Turbulent Combustion'', a monograph with excellent but challenging insights on the advances, problems, and active research in the field of combustion in turbulent flow media. He was well known for his ideas on the Laminar flamelet model in turbulent combustion as well as for the systematic generation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, and highly combustible. Hydrogen is the most abundant chemical substance in the universe, constituting roughly 75% of all normal matter.However, most of the universe's mass is not in the form of baryons or chemical elements. See dark matter and dark energy. Stars such as the Sun are mainly composed of hydrogen in the plasma state. Most of the hydrogen on Earth exists in molecular forms such as water and organic compounds. For the most common isotope of hydrogen (symbol 1H) each atom has one proton, one electron, and no neutrons. In the early universe, the formation of protons, the nuclei of hydrogen, occurred during the first second after the Big Bang. The emergence of neutral hydrogen atoms throughout the universe occurred about 370,000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogenation, C=C (and other) bonds ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Monoxide
Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simplest molecule of the oxocarbon family. In coordination complexes the carbon monoxide ligand is called carbonyl. It is a key ingredient in many processes in industrial chemistry. The most common source of carbon monoxide is the partial combustion of carbon-containing compounds, when insufficient oxygen or heat is present to produce carbon dioxide. There are also numerous environmental and biological sources that generate and emit a significant amount of carbon monoxide. It is important in the production of many compounds, including drugs, fragrances, and fuels. Upon emission into the atmosphere, carbon monoxide affects several processes that contribute to climate change. Carbon monoxide has important biological roles across phylogenetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forman A
Forman may refer to: Places: *Forman, North Dakota, city in Sargent County, North Dakota, United States * Forman, West Virginia, unincorporated community in Grant County, West Virginia, United States * Forman Glacier between Mount Franke and Mount Cole, in the Queen Maud Mountains of Antarctica *Forman Park, in Syracuse, New York Surname: *A. G. Forman CBE (1910–1967), Chief of Naval Staff of the Ghana Navy * Al Forman (1928–2013), baseball umpire *Alexander A. Forman (1843–1922), American soldier in the American Civil War *Alison Forman (born 1969), Australian soccer player *Andrew Forman (1465–1521), Scottish diplomat and Archbishop *Arthur Forman (1850–1905), English schoolmaster and cricketer *Bill Forman (1886–1958), baseball player * Bruce Forman (born 1956), American jazz guitarist *Carol Forman (1918–1997), American actress *Charles William Forman (1821–1894), Presbyterian missionary in Pakistan *Christine Jones Forman, American astrophysicist *Craig Forman ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeldovich–Liñán Model
In combustion, Zel'dovich–Liñán model is a two-step reaction model for the combustion processes, named after Yakov Borisovich Zel'dovich and Amable Liñán. The model includes a chain-branching and a chain-breaking (or radical recombination) reaction. The model was first introduced by Zel'dovich in 1948 and later analysed by Liñán using activation energy asymptotics in 1971. The mechanism reads as : \begin \rm + \rm &\rightarrow 2\rm \\ \rm + \rm + \rm &\rightarrow 2\rm +\rm \end where \rm is the fuel, \rm is an intermediate radical, \rm is the third body and \rm is the product. The first reaction is the chain-branching reaction, which is considered to be auto-catalytic (consumes no heat or releases no heat), with very large activation energy and the second reaction is the chain-breaking (or radical-recombination) reaction, where all of the heat in the combustion is released, with almost negligible activation energy In chemistry and physics, activation energy is the minimu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Kinetics
Chemical kinetics, also known as reaction kinetics, is the branch of physical chemistry that is concerned with understanding the rates of chemical reactions. It is to be contrasted with chemical thermodynamics, which deals with the direction in which a reaction occurs but in itself tells nothing about its rate. Chemical kinetics includes investigations of how experimental conditions influence the speed of a chemical reaction and yield information about the reaction's mechanism and transition states, as well as the construction of mathematical models that also can describe the characteristics of a chemical reaction. History In 1864, Peter Waage and Cato Guldberg pioneered the development of chemical kinetics by formulating the law of mass action, which states that the speed of a chemical reaction is proportional to the quantity of the reacting substances.C.M. Guldberg and P. Waage,"Studies Concerning Affinity" ''Forhandlinger i Videnskabs-Selskabet i Christiania'' (1864), 35P. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reaction Mechanisms
Reaction may refer to a process or to a response to an action, event, or exposure: Physics and chemistry *Chemical reaction *Nuclear reaction *Reaction (physics), as defined by Newton's third law *Chain reaction (other). Biology and medicine *Adverse drug reaction *Allergic reaction *Reflex, neural reaction *Hypersensitivity, immune reaction * Intolerance (other) * Light reaction (other). Psychology *Emotional, reaction *Reactivity (behaviour) *Proactivity, opposite of reactive behaviour *Reactive attachment disorder. Politics and culture *Reactionary, a political tendency *Reaction video *Commentary (other). Proper names and titles * ''Reaction'' (album), a 1986 album by American R&B singer Rebbie Jackson ** "Reaction" (song), the title song from the Rebbie Jackson album *"Reaction", a single by Dead Letter Circus *ReAction GUI, a GUI toolkit used on AmigaOS *Reaction.life, a political news and commentary website edited by Iain Martin *R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reactions
A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more products, which usually have properties different from the reactants. Reactions often consist of a sequence of individual sub-steps, the so-called elementary reactions, and the information on the precise course of acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
