Relevant bibliographies by topics / Oxidation-reduction reaction Chemistry

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Oxidation-reduction reaction Chemistry'

Author: Grafiati
Published: 4 June 2021
Last updated: 3 February 2022

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Journal articles on the topic "Oxidation-reduction reaction Chemistry"

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Morkovnik, Anatolii S. "The Oxidation-reduction Stage in the Nitration Reaction." Russian Chemical Reviews 57, no. 2 (February 28, 1988): 144–60. http://dx.doi.org/10.1070/rc1988v057n02abeh003341.

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Čížek, Milan. "Reduction of nitrogen oxide by ammonia. Oxidation state of V2O5/Al2O3 catalysts and reaction mechanism." Collection of Czechoslovak Chemical Communications 55, no. 10 (1990): 2390–94. http://dx.doi.org/10.1135/cccc19902390.

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When the (NO + NH3 + O2) reaction is carried out over V2O5/Al2O3, the catalysts are partially reduced, and prereduced catalysts are oxidized by the reaction mixture at a slower rate than by an O2 + N2 mixture. The degree of catalyst reduction in the (NO + NH3 + O2) reaction depends on the gas phase composition and particularly on the vanadium loading of the catalyst. The initial oxidation state of catalyst has an effect on the catalyst activity for the reaction. Rate-determining reduction and oxidation steps of the so-called reduction-oxidation mechanism are proposed on the basis of a comparison of the reduction and oxidation of the catalyst by the reaction components.
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Hashimoto, Shinobu, and Akira Yamaguchi. "Synthesis of Mg2SiO4Whiskers by an Oxidation-Reduction Reaction." Journal of the American Ceramic Society 78, no. 7 (July 1995): 1989–91. http://dx.doi.org/10.1111/j.1151-2916.1995.tb08926.x.

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Cho, Yunhee, Thi Anh Le, and Hyoyoung Lee. "Understanding Surface Modulation to Improve the Photo/Electrocatalysts for Water Oxidation/Reduction." Molecules 25, no. 8 (April 23, 2020): 1965. http://dx.doi.org/10.3390/molecules25081965.

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Water oxidation and reduction reactions play vital roles in highly efficient hydrogen production conducted by an electrolyzer, in which the enhanced efficiency of the system is apparently accompanied by the development of active electrocatalysts. Solar energy, a sustainable and clean energy source, can supply the kinetic energy to increase the rates of catalytic reactions. In this regard, understanding of the underlying fundamental mechanisms of the photo/electrochemical process is critical for future development. Combining light-absorbing materials with catalysts has become essential to maximizing the efficiency of hydrogen production. To fabricate an efficient absorber-catalysts system, it is imperative to fully understand the vital role of surface/interface modulation for enhanced charge transfer/separation and catalytic activity for a specific reaction. The electronic and chemical structures at the interface are directly correlated to charge carrier movements and subsequent chemical adsorption and reaction of the reactants. Therefore, rational surface modulation can indeed enhance the catalytic efficiency by preventing charge recombination and prompting transfer, increasing the reactant concentration, and ultimately boosting the catalytic reaction. Herein, the authors review recent progress on the surface modification of nanomaterials as photo/electrochemical catalysts for water reduction and oxidation, considering two successive photogenerated charge transfer/separation and catalytic chemical reactions. It is expected that this review paper will be helpful for the future development of photo/electrocatalysts.
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Preet, Anant, and Tzu-En Lin. "A Review: Scanning Electrochemical Microscopy (SECM) for Visualizing the Real-Time Local Catalytic Activity." Catalysts 11, no. 5 (May 4, 2021): 594. http://dx.doi.org/10.3390/catal11050594.

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Scanning electrochemical microscopy (SECM) is a powerful scanning probe technique for measuring the in situ electrochemical reactions occurring at various sample interfaces, such as the liquid-liquid, solid-liquid, and liquid-gas. The tip/probe of SECM is usually an ultramicroelectrode (UME) or a nanoelectrode that can move towards or over the sample of interest controlled by a precise motor positioning system. Remarkably, electrocatalysts play a crucial role in addressing the surge in global energy consumption by providing sustainable alternative energy sources. Therefore, the precise measurement of catalytic reactions offers profound insights for designing novel catalysts as well as for enhancing their performance. SECM proves to be an excellent tool for characterization and screening catalysts as the probe can rapidly scan along one direction over the sample array containing a large number of different compositions. These features make SECM more appealing than other conventional methodologies for assessing bulk solutions. SECM can be employed for investigating numerous catalytic reactions including the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), water oxidation, glucose oxidation reaction (GOR), and CO2 reduction reaction (CO2RR) with high spatial resolution. Moreover, for improving the catalyst design, several SECM modes can be applied based on the catalytic reactions under evaluation. This review aims to present a brief overview of the recent applications of electrocatalysts and their kinetics as well as catalytic sites in electrochemical reactions, such as oxygen reduction, water oxidation, and methanol oxidation.
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Imyanitov, Naum S. "Is This Reaction a Substitution, Oxidation-Reduction, or Transfer?" Journal of Chemical Education 70, no. 1 (January 1993): 14. http://dx.doi.org/10.1021/ed070p14.

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Nguyen, Bichlien H., Robert J. Perkins, Jake A. Smith, and Kevin D. Moeller. "Photovoltaic-driven organic electrosynthesis and efforts toward more sustainable oxidation reactions." Beilstein Journal of Organic Chemistry 11 (February 23, 2015): 280–87. http://dx.doi.org/10.3762/bjoc.11.32.

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The combination of visible light, photovoltaics, and electrochemistry provides a convenient, inexpensive platform for conducting a wide variety of sustainable oxidation reactions. The approach presented in this article is compatible with both direct and indirect oxidation reactions, avoids the need for a stoichiometric oxidant, and leads to hydrogen gas as the only byproduct from the corresponding reduction reaction.
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Hashimoto, Shinobu, and Akira Yamaguchi. "Synthesis of MgAl2O4 Whiskers by an Oxidation-Reduction Reaction." Journal of the American Ceramic Society 79, no. 2 (February 1996): 491–94. http://dx.doi.org/10.1111/j.1151-2916.1996.tb08150.x.

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Ramesh, P. D., and K. J. Rao. "Carbothermal reduction and nitridation reaction of SiOx and preoxidized SiOx: Formation of α-Si3N4 fibers." Journal of Materials Research 9, no. 9 (September 1994): 2330–40. http://dx.doi.org/10.1557/jmr.1994.2330.

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The chemical composition of amorphous SiOx has been analyzed by oxidation studies and is found to be SiO1.7. SiO1.7 appears to be a monophasic amorphous material on the basis of 29Si nuclear magnetic resonance, high resolution electron microscopy, and comparative behavior of a physical mixture of Si and SiO2. Carbothermal reduction and nitridation reactions have been carried out on amorphous SiO1.7 and on amorphous SiO2 obtained from oxidation of SiO1.7. At 1623 K reactions of SiO1.7 lead exclusively to the formation of Si2N2O, while those of SiO2 lead exclusively to the formation of Si3N4. Formation of copious fibers of α-Si3N4 was observed in the latter reaction. It is suggested that the partial pressure of SiO in equilibrium with reduced SiO1.7 and SiO2 during the reaction is the crucial factor that determines the chemistry of the products. The differences in the structures of SiO2 and SiO1.7 have been considered to be the origin of the differences in the SiO partial pressures of the reduction products formed prior to nitridation. The effect of the ratios, C:SiO1.7 and C:SiO2, in the reaction mixture as well as the effect of the temperature on the course of the reactions have also been investigated.
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Guerrero-Pérez, M. "V-Containing Mixed Oxide Catalysts for Reduction–Oxidation-Based Reactions with Environmental Applications: A Short Review." Catalysts 8, no. 11 (November 20, 2018): 564. http://dx.doi.org/10.3390/catal8110564.

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V-containing mixed oxide catalytic materials are well known as active for partial oxidation reactions. Oxidation reactions are used in industrial chemistry and for the abatement of pollutants. An analysis of the literature in this field during the past few years shows a clear increase in the use of vanadium-based materials as catalysts for environmental applications. The present contribution makes a brief revision of the main applications of vanadium containing mixed oxides in environmental catalysis, analyzing the properties that present the catalysts with a better behavior that, in most cases, is related with the stabilization of reduced vanadium species (as V4+/V3+) during reaction.
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Dissertations / Theses on the topic "Oxidation-reduction reaction Chemistry"

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Moritz, Paul Stuart. "Substitution and redox chemistry of ruthenium complexes /." Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phm862.pdf.

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Davies, Arthur John. "The development and teaching of redox concepts /." Title page, table of contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09EDM/09edmd255.pdf.

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Gunawardhana, Kihanduwage N. Gipson Stephen L. "Chemistry, electrochemistry and electron transfer induced reactions of cobalt complexes with fluorinated ligands." Waco, Tex. : Baylor University, 2007. http://hdl.handle.net/2104/5114.

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Thesis (Ph.D.)--Baylor University, 2007.
In the abstract "CF3COCo(CO)3PPh3, CF3, Bu3SnH, CF3H, [Co(CO)4]-, [Co(CO)3(PPh3)]-, C2F4, C6F5Co(CO)3PPh3, C6F5, C6F5H, C6F5D, CF3COCo(CO)3PPh3, and Co-C(acyl)" are subscript. Includes bibliographical references (p. 205-213).
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Faierson, Eric J. "Influences of Reaction Parameters on the Product of a Geothermite Reaction: A Multi-Component Oxidation-Reduction Reaction Study." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/32327.

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This study investigated an oxidation-reduction reaction involving a mixture of minerals, glass, and aluminum that exhibited thermite-type reaction behavior. Thermite reactions are a class of Self-propagating High-temperature Synthesis (SHS) reactions. Chemical reactions between raw minerals and a reducing agent, which exhibit thermite-type reaction behavior, are termed geothermite reactions by the author. Geothermite reactions have the potential for use in In-Situ Resource Utilization (ISRU) applications on the Earth, the Moon, Mars, and beyond.

A geothermite reaction was shown to occur between two particle size distributions of lunar regolith simulant. Regolith simulant is a naturally occurring mixture of minerals and glass mined from a volcanic ash deposit. The chemical composition of the simulant is similar to actual lunar regolith found on the Moon. The product of the reaction was a ceramic-composite material. The effect of reactant stoichiometry, regolith simulant particle size, and reaction environment on phase formation, microstructure, and compressive strength of the reaction product was investigated. Reaction environments used in this study included a standard atmosphere and a vacuum environment of 0.600 Torr. In addition, the energy required to initiate each reaction using various reaction parameters was measured.

X-ray diffraction (XRD) analysis of reaction products synthesized in a standard atmosphere and in vacuum typically indicated the presence of the chemical species: silicon, corundum (α -Al2O3), spinel (MgAl2O4), and grossite (CaAl4O7). Many additional chemical species were present; their occurrence depended on reaction parameters used during synthesis. Diffraction peaks were observed for phases of aluminum nitride within all reaction products formed in a standard atmosphere. Scanning Electron Microscopy (SEM) showed the presence of whisker networks throughout the microstructure for all reactions conducted in a standard atmosphere. Energy Dispersive Spectroscopy (EDS) indicated the presence of aluminum and nitrogen within many of the whiskers. It was hypothesized that many of the whisker networks were composed of phases of aluminum nitride. No whisker networks were observed in the vacuum synthesized reaction products. Maximum mean compressive strengths were found to be ~ 18 MPa and occurred in the coarse particle size distribution of simulant using the smallest quantity of aluminum. Reactant mixtures using a coarse particle size distribution of regolith simulant were found to require substantially more energy to initiate the reaction than the simulant with the fine particle size distribution.
Master of Science

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LaButti, Jason N. Gates Kent S. "Investigations into the chemistry of protein tyrosine phosphatase redox regulation." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6158.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 15, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Kent S. Gates. Vita. Includes bibliographical references.
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Hoefler, Christoph. "Preparation of electron donor and acceptor molecules for porphyrin derivatization." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/4317.

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Porphyrins derivatized with electron donating and electron withdrawing groups can be used for artificial photosynthesis. Four new compounds, two electron donors and two electron acceptors, have been synthesized for prospective porphyrin linkages.
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Tuschel, David Daniel 1957. "A CHARACTERIZATION OF THE OXIDATION-REDUCTION CYCLE AND SURFACE MORPHOLOGY OF ELECTROCHEMICAL SURFACE ENHANCED RAMAN SCATTERING." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/277026.

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Wycoff, Donald E. "Catalysis of interfacial transfer of photo-generated electrons : a study of four molybdenum-sulfur complex ions mediating electron transfer across a colloidal semiconductor-liquid interface /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3164554.

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Sivaramakrishnan, Santhosh Gates Kent S. "Biologically relevant chemistry of sulfur heterocycles from redox regulation of PTP1B to the biological activity of s-deoxy leinamycin." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/7107.

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Title from PDF of title page (University of Missouri--Columbia, viewed on March 2, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dr. Kent S. Gates, Dissertation Supervisor. Vita. Includes bibliographical references.
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Cuzan, Olesea. "Synthesis and characterization of new transition metal complexes for catalytic oxidation and electrolytic proton reduction." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4356/document.

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De nos jours, la capacité à synthétiser de nouveaux catalyseurs métallique bioinspirés pour améliorer et élargir le spectre d'activité catalytique est d’une importance capitale pour une chimie respectueuse de notre environnement.Cette thèse se concentre sur la conception de nouveaux complexes de métaux de transition (cuivre et palladium) basés sur deux classes différentes de ligands organiques : les benzotriazolyle-phénolates et les phosphonates. La synthèse et la caractérisation de nouveaux composés a été réalisée par différentes méthodes physico-chimiques (électrochimie, EPR, UV-vis, IR, cristallographie aux rayons X) et la chimie théorique. La génération et la caractérisation des différentes espèces réduites et oxydées nous ont aidés dans la détermination des mécanismes possible. Les composés obtenus ont été utilisés avec succès comme catalyseurs dans divers procédés tels que: la production d'hydrogène, l'oxydation d'alcool et le clivage d'ADN
Nowadays, the ability to synthesize new bioinspired metal catalysts to improve and broaden the spectrum of catalytic activity is of paramount importance for sustainable chemistry respectful for our environment. This thesis is focused on the design of transition metal complexes (copper and palladium) based on two different classes of organic ligands: benzotriazolyl-phenolates and phosphonates.Different original complexes based on palladium and copper were synthetized from benzotriazolyl-phenolate and phosphonates ligands. The characterization of the new compounds was performed by different physical and physico-chemical methods (electrochemistry, EPR, UV-vis, IR, X-ray crystallography) and quantum chemistry. The generation and characterization of different reduced and oxidized species helped us in the possible mechanisms determination. The obtained compounds were successfully employed as catalysts in different processes as: hydrogen production, alcohol oxidation and DNA cleavage
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Books on the topic "Oxidation-reduction reaction Chemistry"

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W, Rees Charles, ed. Electron transfer reactions in organic chemistry. Berlin: Springer-Verlag, 1987.

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Molecular basis of oxidative stress: Chemistry, mechanisms, and disease pathogenesis. Hoboken, New Jersey: Wiley, 2013.

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Oxidation and reduction in inorganic and analytical chemistry: A programmed introduction. Chichester: Wiley, 1985.

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1941-, Ulstrup Jens, ed. Electron transfer in chemistry and biology: An introduction to the theory. Chichester: Wiley, 1999.

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Mahrwald, Rainer. Enantioselective Organocatalyzed Reactions I: Enantioselective Oxidation, Reduction, Functionalization and Desymmetrization. Dordrecht: Springer Science+Business Media B.V., 2011.

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Jobe, David James. Iron oxide redox chemistry and nuclear fuel disposal. Pinawa, Man: Whiteshell Laboratories, 1997.

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American Chemical Society. Division of Environmental Chemistry and American Chemical Society. Division of Geochemistry, eds. Aquatic redox chemistry. Washington, DC: American Chemical Society, 2011.

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Fred, Webber, ed. Trends and patterns. Cambridge: CambridgeUniversity Press, 1996.

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International Symposium on Redox Mechanisms and Interfacial Properties of Molecules of Biological Importance (3rd 1987 Honolulu, Hawaii). Redox chemistry and interfacial behavior of biological molecules. New York: Plenum, 1988.

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Lappin, Graham. Redox mechanisms in inorganic chemistry. New York: Ellis Horwood, 1994.

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Book chapters on the topic "Oxidation-reduction reaction Chemistry"

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Rosenthal, Deborah P., and Michael J. Sanger. "How Does the Order of Viewing Two Computer Animations of the Same Oxidation-Reduction Reaction Affect Students’ Particulate-Level Explanations?" In Pedagogic Roles of Animations and Simulations in Chemistry Courses, 313–40. Washington, DC: American Chemical Society, 2013. http://dx.doi.org/10.1021/bk-2013-1142.ch013.

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Meyer, Thomas J. "Oxidation-Reduction and Related Reactions of Metal-Metal Bonds." In Progress in Inorganic Chemistry, 1–50. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470166208.ch1.

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Lluch, José M. "Perspective on “On the theory of oxidation—reduction reactions involving electron transfer. I”." In Theoretical Chemistry Accounts, 231–33. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-662-10421-7_20.

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Oriakhi, Christopher O. "Oxidation and Reduction Reactions." In Chemistry in Quantitative Language. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780195367997.003.0026.

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Oxidation-reduction reactions, or redox reactions, occur in many chemical and biochemical systems. The process involves the complete or partial transfer of electrons from one atom to another. Oxidation and reduction processes are complementary. For every oxidation, there is always a corresponding reduction process. This is because for a substance to gain electrons in a chemical reaction, another substance must be losing these electrons. Oxidation is defined as a process by which an atom or ion loses electrons. This can occur in several ways: • Addition of oxygen or other electronegative elements to a substance:. . . 2 Mg(s)+O2(g) → 2 MgO(s) . . .2 Mg(s)+O2(g) → MgCl2 (s). . . • Removal of hydrogen or other electropositive elements from a substance: . . . H2S(g)+Cl2(g) → 2 HCl(g)+S(s) . . .Here, H2S is oxidized. • The direct removal of electrons from a substance: . . . 2 FeCl2 (s)+Cl2(g) → 2 FeCl3 (s) . . . Fe2+ → Fe3+ +e− . . . Reduction is defined as the process by which an atom or ion gains electrons. This can occur in the following ways: • Removal of oxygen or other electronegative elements from a substance: . . . MgO(s)+H2(g) → Mg(s)+H2O(g). . . • Addition of hydrogen or other electropositive elements to a substance: . . . H2(g)+Br2(g) → 2 HBr(g). . . 2 Na(s)+Cl2(g) → 2 NaCl(s). . . Here, chlorine (Cl2) is reduced. • The addition of electrons to a substance: . . . Fe3+ +e− → Fe2+ . . . Oxidation number or oxidation state is a number assigned to the atoms in a substance to describe their relative state of oxidation or reduction. These numbers are used to keep track of electron transfer in chemical reactions. Some general rules are used to determine the oxidation number of an atom in free or combined state. 1. Any atom in an uncombined (or free) element (e.g., N2, Cl2, S8, O2, O3, and P4) has an oxidation number of zero. 2. Hydrogen has an oxidation number of +1 except in metal hydrides (e.g., NaH, MgH2) where it is −1. 3. Oxygen has an oxidation number of −2 in all compounds except in peroxides (e.g., H2O2, Na2O2) where it is –1.
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Oriakhi, Christopher O. "Fundamentals of Electrochemistry." In Chemistry in Quantitative Language. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780195367997.003.0027.

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Electrochemistry is the branch of chemistry that deals with the interconversion of chemical and electrical energy. A galvanic (or voltaic) cell is a chemical system that uses an oxidation–reduction reaction to convert chemical energy into electrical energy (hence it is also known as an electrochemical cell). This process is the opposite of electrolysis (explained in section 23.10), wherein electrical energy is used to bring about chemical changes. The two systems are similar in that both are redox processes; in both, the oxidation takes place at one electrode, the anode, while reduction occurs at the cathode. Figure 23-1 shows a galvanic cell, indicating the half-reactions at the two electrodes. Electrons flow through the external circuit from the anode (Zn) to the cathode (Cu). The overall reaction, which is obtained by adding the anodic and cathodic half-cell reactions, is: . . .Zn(s)+Cu2+(aq) → Zn2+(aq)+Cu(s). . . This cell has a potential of 1.10 V (see next section). The potential energy of electrons at the anode is higher than at the cathode. This difference in potential is the driving force that propels electrons through the external circuit. The cell potential (Ecell) is a measure of the potential difference between the two half-cells. It is also known as the electromotive force (emf) of the cell, or, since it is measured in volts, the cell voltage. An electrochemical cell consists of two half-reactions at different potentials, which are known as electrode potentials. The electrode potential for the oxidation half-reaction is called the oxidation potential. Similarly, for the reduction half-reaction, we have the reduction potential. The potential of a galvanic cell is determined by the concentrations of the species in solution, the partial pressures of any gaseous reactants or products, and the reaction temperature. When the electrochemical measurement is carried out under standard-state conditions, the cell potential is called the standard electrode potential and is given the symbol E0. The standard conditions include a concentration of 1 M, gaseous partial pressure of 1 atm, and a temperature of 25°C. It is impossible to measure the absolute potential value of a single electrode, since every oxidation is accompanied by a reduction. Therefore any measurement is carried out against a reference electrode.
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Sitta, E., K. N. da Silva, and J. M. Feliu. "Hydrogen Peroxide Oxidation/Reduction Reaction on Platinum Surfaces." In Encyclopedia of Interfacial Chemistry, 682–89. Elsevier, 2018. http://dx.doi.org/10.1016/b978-0-12-409547-2.13341-4.

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Lambert, Tristan H. "Flow Chemistry." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0016.

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Although photocatalytic chemistry has been the subject of intense interest recently, the rate of these reactions is often slow due to the limited penetration of light into typical reaction media. Peter H. Seeberger at the Max-Planck Institute for Colloids and Surfaces in Potsdam and the Free University of Berlin showed (Chem. Sci. 2012, 3, 1612) that Ru(bpy)32+-catalyzed reactions such as the reduction of azide 1 to 2 can be achieved in as little as 1 min residence time using continuous flow, as opposed to the 2 h batch reaction time previously reported. The benefits of flow on a number of strategic photocatalytic reactions, including the coupling of 3 and 4 to produce 5, was also demonstrated (Angew. Chem. Int. Ed. 2012, 51, 4144) by Corey R.J. Stephenson at Boston University and Timothy F. Jamison at MIT. In this case, a reaction throughput of 0.914 mmol/h compares favorably with 0.327 mmol/h for the batch reaction. Professor Seeberger has also reported (Angew. Chem. Int. Ed. 2012, 51, 1706) a continuous-flow synthesis of Artemisinin 7, a highly effective antimalarial drug, starting from dihydroartemisinic acid 6. The conversion occurs by a sequence of photochemical oxidation with singlet oxygen, acidic Hock cleavage of the O–O bond, and oxidation with triplet oxygen, a process calculated to be capable of furnishing up to 200 g/day per reactor. A scalable intramolecular [2 + 2] photocycloaddition of 8 to produce 9 was reported (Tetrahedron Lett. 2012, 53, 1363) by Matthias Nettekoven of Hoffmann-La Roche in Basel, Switzerland. Stephen L. Buchwald at MIT developed (Angew. Chem. Int. Ed. 2012, 51, 5355) a flow process for the enantioselective β-arylation of ketones that involved lithiation of aryl bromide 10, borylation, and rhodium-catalyzed conjugate addition to cycloheptenone. For continuous flow production of enantioenriched alcohols such as 14, Miquel A. Pericás of the Institute of Chemical Research of Catalonia developed (Org. Lett. 2012, 14, 1816) the robust polystyrene-supported aminoalcohol 13 for diethylzinc addition to aldehydes. Professor Jamison found (Org. Lett. 2012, 14, 568) that flow chemistry provides a convenient and reliable solution to the reduction of esters to aldehydes with DIBALH (e.g., 15 to 16) that occurs rapidly and without the usual problem of overreduction.
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Schweitzer, George K., and Lester L. Pesterfield. "Reactions and Applications." In The Aqueous Chemistry of the Elements. Oxford University Press, 2010. http://dx.doi.org/10.1093/oso/9780195393354.003.0005.

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E–pH diagrams involve two types of reactions: (1) Non-redox full reactions and (2) Redox half-reactions. Non-redox full reactions are exemplified by ones such as Mn(OH)2 + 2H+ → Mn+2 + 2HOH. This is not a redox (reduction–oxidation) reaction, since there are no changes in oxidation numbers of the elements. Such reactions are reflected as vertical lines on E–pH diagrams. An example of a redox half-reaction is 2e− + Mn+2 → Mn. As can be seen, this is a redox reaction, since electrons appear in the equation, and there is an oxidation number change (II to 0 for Mn). Such reactions are represented by horizontal or sloped lines in an E–pH diagram. In order to write complete reactions in which oxidation numbers change, two half-reactions must be combined. One half reaction will represent a reduction (2e− + Mn+2 → Mn) and the other will represent an oxidation (Mg → Mg+2 + 2e−). These half-reactions are combined such that the electrons cancel out and a complete redox equation is obtained (Mn+2 + Mg →Mn + Mg+2). Each of the two half-reactions has an E value, and the E value of the resulting complete redox equation is obtained by the difference in the E values of the contributing half-reactions. E–pH diagrams may be employed to predict non-redox full reactions and complete redox reactions and to ascertain E values of the latter. This will be the subject matter of the next few sections. Dashed lines in every E–pH diagram represent the E values for changes in HOH-related species (HOH, H+, H2, O2, and implicitly OH−). The upper dashed sloped line represents the reaction 4e− + 4H+ + O2 → 2HOH and is described by the equation E = 1.23−0.059 pH. The lower dashed sloped line represents the reaction 2e− + 2H+ → H2 and is described by the equation E= 0.00−0.059 pH. Figure 3.1 shows the E–pH diagram for HOH, and Figure 3.2 shows the E–pH diagram for Mg with all soluble species at 1.00 M except H+. The solid horizontal line represents the reaction 2e− + Mg+2 → Mg, and the equation for the line is E = −2.36 + 0.030 log [Mg+2].
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Bunker, Bruce C., and William H. Casey. "The Electrochemistry of Oxides." In The Aqueous Chemistry of Oxides. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780199384259.003.0018.

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Many of the critical reactions considered in this book involve the addition or subtraction of protons from oxides. In this chapter, we consider another species that can change oxide charge distributions and reactivity dramatically: the electron. Many oxides contain cations that have access to more than one oxidation state in water. Cations in these oxides can either donate or accept electrons to change their charge, or oxidation state. Oxidation reactions involve the loss of electrons as they are donated to other species, resulting in an increase in the cation charge or valence, whereas reduction reactions involve the capture of an electron resulting in a decrease in the cation valence. Below, the basics of electrochemistry are first described in the context of the redox chemistry of water and representative oxide systems. Second, we describe the fundamentals of electron-transfer reactions in oxides and the impact of electron transfer on the acid–base, ion-exchange, and ligand-exchange reactions of the host oxide. Finally, we discuss the behavior of oxides in electrochemical energy storage devices and the role that nanotechnology has in optimizing electrochemical performance. Electrochemical reactions are typically written in the context of the geometry of a battery or a galvanic cell. For the cell shown in Figure 11.2, which contains metal electrodes immersed in aqueous solutions containing solvated cations, the net reaction can be written as . . . Cu°(s)+2Fe3+ (aq) ⇄2Fe2+ (aq)+Cu2+ (aq) (11.1). . . In this reaction, Cu metal is being oxidized to form Cu(II), whereas Fe(III) is being reduced to form Fe(II). The individual oxidation and reduction reactions leading to Eq. 11.1 are referred to as half-reactions: Cu°(s) ⇄Cu2+ (aq)+2e- Eo =−0.34 V (11.2) 2Fe3+ (aq) ⇄2Fe2+ (aq)+ Fe 2- (aq) Eo =+0.77 V (11.3) . . . The net result of Eqs. 11.2 and 11.3 in the context of Figure 11.2 is the transfer of electrons from the Cu-containing compartment in which oxidation occurs, which is called the anode, to the Fe-containing compartment in which reduction occurs, which is called the cathode. This electron transfer generates an electric current, a charge-compensating ion current (in the salt bridge), as well as a voltage.
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Oriakhi, Christopher O. "Volumetric Analysis." In Chemistry in Quantitative Language. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780195367997.003.0018.

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Volumetric analysis is a chemical analytical procedure based on measurement of volumes of reaction in solutions. It uses titration to determine the concentration of a solution by carefully measuring the volume of one solution needed to react with another. In this process, a measured volume of a standard solution, the titrant, is added from a burette to the solution of unknown concentration. When the two substances are present in exact stoichiometric ratio, the reaction is said to have reached the equivalence or stoichiometric point. In order to determine when this occurs, another substance, the indicator, is also added to the reaction mixture. This is an organic dye which changes color when the reaction is complete. This color change is known as the end point; ideally, it will coincide with the equivalence point. For various reasons, there is usually some difference between the two, though if the indicator is carefully chosen, the difference will be negligible. A typical titration is based on a reaction of the general type aA+bB → products where A is the titrant, B the substance titrated, and a:b is the stoichiometric ratio between the two. Some indicators include Litmus, Methyl Orange, Methyl Red, Phenolphthalein, and Thymol Blue. Titration can be applied to any of the following chemical reactions: • Acid–base • Complexation • Oxidation–reduction • Precipitation Only acid–base and oxidation–reduction titration will be treated here, though the fundamental principles are the same in all cases. Acid–base titration involves measuring the volume of a solution of the acid (or base) that is required to completely react with a known volume of a solution of a base (or acid). The relative amounts of acid and base required to reach the equivalence point depend on their stoichiometric coefficients. It is therefore critical to have a balanced equation before attempting calculations based on acid–base reactions. Below we define some of the common terms associated with acid–base reactions. A molar solution is one that contains one mole of the substance per liter of solution. For example, a molar solution of sodium hydroxide contains 40 g (NaOH=40 g/mol) of the solute per liter of solution. As described in chapter 13, the concentration of a solution expressed in moles per liter of solution is known as the molarity of the solution.
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Conference papers on the topic "Oxidation-reduction reaction Chemistry"

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Selim, H., A. K. Gupta, and M. Sassi. "Reduced Mechanism for the Oxidation of Hydrogen Sulfide." In ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/detc2009-86497.

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Hydrogen sulfide is one of the most common gases accompanying fuels in oil and gas refinery processes. This gas has very harmful effect on the human health and environment so that it must be removed in an effective and efficient manner before using this fuel. These problems triggered the interest to study the chemistry of hydrogen sulfide oxidation, as it is mainly treated by chemical reactions. Simplification of the reaction mechanism will enable us to understand the properties of the chemical processes that occur during the process of hydrogen sulfide treatment. Reduction strategy is carried out here in order to reduce the detailed mechanism, where the direct relation graph and error propagation methodology (DRGEP) has been used in this paper. The results obtained from the resulting reduced mechanism showed very good agreement with the detailed chemistry results under different reaction conditions. However, some discrepancies have been found for some species, especially in the hydrogen and oxygen mole fractions. The reduced mechanism is also capable of tracking the difference in chemical kinetics that takes place due to the change in reaction conditions.
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Kong, Song-Charng, Yong Sun, and Rolf D. Reitz. "Modeling Diesel Spray Flame Lift-Off, Sooting Tendency and NOx Emissions Using Detailed Chemistry With Phenomenological Soot Model." In ASME 2005 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ices2005-1009.

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A detailed chemistry-based CFD model was developed to simulate the diesel spray combustion and emission process. A reaction mechanism of n-heptane is coupled with a reduced NOx mechanism to simulate diesel fuel oxidation and NOx formation. The soot emission process is simulated by a phenomenological soot model that uses a competing formation and oxidation rate formulation. The model is applied to predict the diesel spray lift-off length and its sooting tendency under high temperature and pressure conditions with good agreement with experiments of Sandia. Various nozzle diameters and chamber conditions were investigated. The model successfully predicts that the sooting tendency is reduced as the nozzle diameter is reduced and/or the initial chamber gas temperature is decreased, as observed by the experiments. The model is also applied to simulate diesel engine combustion under PCCI-like conditions. Trends of heat release rate, NOx and soot emissions with respect to EGR levels and start-of-injection timings are also well predicted. Both experiments and models reveal that soot emissions peak when the start of injection occurs close to TDC. The model indicates that low soot emission at early SOI is due to better oxidation while low soot emission at late SOI is due to less formation. Since NOx emissions decrease monotonically with injection retardation, a late injection scheme can be utilized for simultaneous soot and NOx reduction for the engine conditions investigated in this study.
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Slavinskaya, N. A. "Chemical Kinetic Modeling in Coal Gasification Processes: An Overview." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-23362.

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Coal is the fuel most able to cover world deficiencies in oil and natural gas. This motivates the development of new and more effective technologies for coal conversion into other fuels. Such technologies are focused on coal gasification with production of syngas or gaseous hydrocarbon fuels, as well as on direct coal liquefaction with production of liquid fuels. The benefits of plasma application in these technologies is based on the high selectivity of the plasma chemical processes, the high efficiency of conversion of different types of coal including those of low quality, relative simplicity of the process control, and significant reduction in the production of ashes, sulphur, and nitrogen oxides. In the coal gasifier, two-phase turbulent flow is coupled with heating and evaporation of coal particles, devolatilization of volatile material, the char combustion (heterogeneous/porous oxidation) or gasification, the gas phase reaction/oxidation (homogeneous oxidation) of gaseous products from coal particles. The present work reviews literature data concerning modelling of coal gasification. Current state of related kinetic models for coal particle gasification, plasma chemistry and CFD tools is reviewed.
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Kurniawan, Budi, Dedi Irwandi, and Nanda Saridewi. "Development of Chemistry Interactive Instructional Media Based on Mobile Learning on Oxidation-Reduction Reactions." In International Conference on Education in Muslim Society (ICEMS 2017). Paris, France: Atlantis Press, 2018. http://dx.doi.org/10.2991/icems-17.2018.19.

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5

Karalus, Megan F., K. Boyd Fackler, Igor V. Novosselov, John C. Kramlich, and Philip C. Malte. "A Skeletal Mechanism for the Reactive Flow Simulation of Methane Combustion." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95904.

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A skeletal mechanism for the prediction of NOx emissions from methane combustion at gas turbine conditions is developed in the present work. The goal is a mechanism that can be used in computational fluid dynamic modeling of lean premixed (LPM) combustors. A database of solutions from 0-D, adiabatic, homogeneous reactors (PSRs) is computed using CHEMKINPRO [1] over a parameter space chosen to include pressures from 1 to 30 atm, equivalence ratios from 0.4 to 1.0, and mean PSR residence times from slightly greater than blowout to 3ms. A resisidence time of 3 ms represents a useful maximum for the super-equilibrium flame zone where most of the NOx forms in LPM combustors. Fuel oxidation and NOx formation are treated separately in the reduction process. The method of Directed Relation Graph (DRG) is applied for methane oxidation and its extension, DRG-aided sensitivity analysis (DRGASA), is used to determine the skeletal NOx mechanism to append to the methane mechanism. Post-processing of the PSR solution database and implementation of the reduction algorithm are accomplished in SAGE [2], a Python based, open-source mathematics software package. The skeletal oxidation and NOx mechanisms are validated against full GRI 3.0 [3] in both PSR and laminar flame speed calculations. When compared with the detailed GRI 3.0 mechanism, NOx emissions are predicted within 7% near blowout and 3% at 3ms, and laminar flame speeds are predicted within 20% over the range of equivalence ratios and pressures. The skeletal mechanism is presented here and it should be noted that all reactions of the H2/CO submechanism are retained. The skeletal mechanism consists of 22 species and 122 reactions for methane oxidation and an additional 8 species and 55 reactions to describe NOx formation (30 species, 177 reactions total). The final skeletal mechanism with NOx chemistry is available for download here [4]. To demonstrate the predictive capability of the validated mechanism in a reactive flow system, it is implemented in an ANSYS Fluent model of a single jet stirred reactor, the results of which are compared to experimental reactor data presented in [5] and [6]. Predicted and measured profiles of temperature and NOx emissions are shown. Temperature and NOx emissions compare well in the recirculation zone of the JSR, although both NOx emissions and temperature are under-predicted in the jet region. Finally, the contribution of each chemical pathway for NOx formation is evaluated.
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Mayer, Luke J., and Darryl L. James. "Experimental Analysis of Flow Crossover in a Solar Thermochemical Reactor." In ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology collocated with the ASME 2012 6th International Conference on Energy Sustainability. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/fuelcell2012-91398.

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As energy and fuel security continue to be of increasing importance to economies around the world, countries are looking to move away from oil dependency. Energy solutions are being sought in the area of solar fuels to meet these growing needs. Concentrated solar thermochemical technology has the potential to directly convert sunlight into a useable, carbon-neutral liquid fuel that can be easily stored and integrated into our existing forms of energy demand such as transportation and heating fuels. Ongoing research performed by several groups at Sandia National Laboratories seeks to fundamentally understand the complex physics and chemistry occurring within a solar thermochemical reactor prototype named the CR5 [counter-rotating-ring receiver/reactor/recuperator]. The CR5 utilizes a stack of counter-rotating disks with metal oxide reactive material fins which are cycled through oxidation and reduction zones. The metal oxide is thus used to reduce H2O and CO2 into H2 and CO respectively, which can be combined using known processes to form a liquid fuel. The effectiveness of such a solar thermochemical reactor depends on its ability to efficiently integrate reduction and oxidation reactions, a solar receiver, thermal recuperation, and separation of end product gases. Efficient separation of end product gases within the reactor is of critical importance as without it, the crossover of gases occurs, which results in lower reduction rates, recombination of end product gases, and additional energy spent in downstream processes. A validation reactor model called the CR5v (v for validation) has been fabricated to validate numerical models of the reactor processes. Crossover testing is done without any chemical reactions (therefore with no O2 or H2 present), but rather by examining the flow of CO2 and Argon. This work presents experimental crossover for the CR5v reactor as a function of ring rotation speed, internal purge gas, and sweep gas to injection gas ratio. Initial crossover experimental results from the CR5v reactor suggest that crossover levels are largely not affected by ring rotation, center purge or injection gas/sweep gas ratio. Argon flow remained on average at a crossover value of 52 %, while CO2 crossover levels were on average around 8 %. The crossover flow in the system is thought to be dominated by the flow rates of the two pumps used in the system and to a lesser degree, the geometry of the system.
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Gong, Bin, Yan-ping Huang, E. Jang, Jin-Hua Liu, Xiao-jiao Xia, and Yong-Fu Zhao. "Ongoing Research of Water Chemistry Effect on SCC Properties of Candidate Materials for SCWR." In 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-15876.

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One key issue during development of Super Critical Water Cooled Reactor (SCWR) is selection of water chemistry operating and control methods for core coolant. Under strong corrosive effect of supercritical water (SCW), the stress corrosion cracking (SCC) sensitivity of materials increases. Most of materials reliably used in PWR or BWR may not be competent for SCWR. Modified austenitic steel and nickel base alloy are hopeful due to low general corrosion rate but failures happen caused by SCC when meet incompatible chemistry environment. The possible options of water chemistry specifications for SCWR should be qualified carefully on SCC effect. This paper introduces research status of SCW chemistry by Nuclear Power Institute of China (NPIC). The SCC behaviors in oxidation and reduction SCW are under study and the testing data will be collected to screen out water chemistry operating strategy for million kilowatts SCWR (CSR1000) under development in China.
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Luo, Zhaoyu, Parvez Sukheswalla, Scott A. Drennan, Mingjie Wang, and P. K. Senecal. "3D Numerical Simulations of Selective Catalytic Reduction of NOx With Detailed Surface Chemistry." In ASME 2017 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/icef2017-3658.

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Environmental regulations have put stringent requirements on NOx emissions in the transportation industry, essentially requiring the use of exhaust after-treatment on diesel fueled light and heavy-duty vehicles. Urea-Water-Solution (UWS) based Selective Catalytic Reduction (SCR) for NOx is one the most widely adopted methods for achieving these NOx emissions requirements. Improved understanding and optimization of SCR after-treatment systems is therefore vital, and numerical investigations can be employed to facilitate this process. For this purpose, detailed and numerically accurate models are desired for in-cylinder combustion and exhaust after-treatment. The present paper reports on 3-D numerical modeling of the Urea-Water-Solution SCR system using Computational Fluid Dynamics (CFD). The entire process of Urea injection, evaporation, NH3 formation and NOx reduction is numerically investigated. The simulation makes use of a detailed kinetic surface chemistry mechanism to describe the catalytic reactions. A multi-component spray model is applied to account for the urea evaporation and decomposition process. The CFD approach also employs an automatic meshing technique using Adaptive Mesh Refinement (AMR) to refine the mesh in regions of high gradients. The detailed surface chemistry NOx reduction mechanism validated by Olsson et al. (2008) is applied in the SCR region. The simulations are run using both transient and steady-state CFD solvers. While transient simulations are necessary to reveal sufficient details to simulate catalytic oxidation during transient engine processes or under cyclic variations, the steady-state solver offers fast and accurate emission solutions. The simulation results are compared to available experimental data, and good agreement between experimental data and model results is observed.
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9

Agrafiotis, Christos, Andreas Becker, Martin Roeb, and Christian Sattler. "Hybrid Sensible/Thermochemical Storage of Solar Energy in Cascades of Redox-Oxide-Pair-Based Porous Ceramics." In ASME 2015 9th International Conference on Energy Sustainability collocated with the ASME 2015 Power Conference, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/es2015-49334.

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The current work is a follow-up of the idea described in previous publications, namely of combining active thermochemical redox oxide pairs like Co3O4/CoO, Mn2O3/Mn3O4 or CuO/Cu2O with porous ceramic structures in order to effectively store solar heat in air-operated Solar Tower Power Plants. In this configuration the storage concept is rendered from “purely” sensible to a “hybrid” sensible/thermochemical one and the current heat storage recuperators to integrated thermochemical reactors/heat exchangers. In addition, the construction modularity of the current state-of-the-art sensible storage systems provides for the implementation of concepts like spatial variation of redox oxide materials chemistry and solid materials porosity along the reactor/heat exchanger, to enhance the utilization of the heat transfer fluid and the storage of its enthalpy. In this perspective the idea of employing cascades of various porous structures, incorporating different redox oxide materials and distributed in a certain rational pattern in space tailored to their thermochemical characteristics and to the local temperature of the heat transfer medium has been set forth and tested. Thermogravimetric analysis (TGA) studies described in previous works have shown that the Co3O4/CoO redox pair with a reduction onset temperature ≈ 885–905°C is capable of stoichiometric, long-term, cyclic reduction-oxidation under a variety of heatup/cooldown rates. Further such studies with the other two powder systems above, described herein, have demonstrated that the Mn3O4/Mn2O3 redox pair is characterized by a large temperature gap between reduction (≈ 950°C) and oxidation (≈ 780–690°C) temperature, whereas the CuO/Cu2O pair cannot work reproducibly and quantitatively since its redox temperature range is narrow and very close to the melting point of Cu2O. Thus, a combination of two such systems, namely Co3O4/CoO and Mn2O3/Mn3O4 has been further explored. Thermal cycling tests with these two powders together under the conditions required for complete oxidation of the less “robust” one, namely Mn3O4/Mn2O3, demonstrated in principle the proof-of-concept of the cascaded configuration, i.e. that both powders can be reduced and oxidized in complementary temperature ranges, extending thus the temperature operation window of the whole storage cascade. A suitably designed test rig where similar experiments in the form of cascades of coated honeycombs and foams can be performed has been built and further such tests are under way.
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Barve, Vinayak V., Ofodike A. Ezekoye, and Noel T. Clemens. "Effects of Flame Lift-Off Height on Soot Processes in Strongly Forced Methane-Air Laminar Diffusion Flames." In ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference collocated with the ASME 2007 InterPACK Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ht2007-32816.

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Previous work has shown that for sufficiently high periodic forcing amplitudes, laminar diffusion flames can burn in an effectively partially premixed mode. Experimental observations show that the luminosity and sooting properties of the forced flames are significantly modified by the presence of strong forcing. In this work, simulations are performed to study the effects of strong forcing on flow field development in strongly forced laminar isothermal jets and methane air diffusion flames. Unforced and strongly forced cold-flow jets are simulated using a higher order finite volume CFD code. The jet was forced by varying the jet exit velocity over a range of forcing amplitudes and frequencies and it was found that the jet Strouhal number (St) was the important parameter in characterizing flowfield development. Further, the forced jets showed increased entrainment and increased entrainment rates as compared to the non-forced jets. The computations are performed for laminar methane–air diffusion flames. The combustion reactions were modeled using detailed gas-phase chemistry and complex thermo-physical properties. The radiation heat transfer was modeled using the S-6 Discrete Ordinates Method. A 2 equation soot chemistry model for soot nucleation, surface growth and oxidation was used. First an unforced flickering methane–air diffusion flame was modeled and then the flame was forced by varying the amplitude and frequency of the fuel velocity in the nozzle. Cases where the peak velocity in the fuel stream reached 6 times the mean velocity are examined. The internal nozzle flow was also simulated since the near-nozzle region was of particular interest due to the strong mixing processes occurring there and the subsequent effect on the flame properties. Lifted forced flames were also examined, and it was found that the partial premixing in the near nozzle region and increased oxygen entrainment in the forced flames can explain the reduction in soot production for the strongly forced flames.
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