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Displaying Results 1 - 7 of 7 on page 1 of 1
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A comprehensive experimental and modeling study of isobutene oxidation
(2016)
Zhou, Chong-Wen; Li, Yang; O'Connor, Eoin; Somers, Kieran P.; Thion, Sébastien; Ke...
A comprehensive experimental and modeling study of isobutene oxidation
(2016)
Zhou, Chong-Wen; Li, Yang; O'Connor, Eoin; Somers, Kieran P.; Thion, Sébastien; Keesee, Charles; Mathieu, Olivier; Petersen, Eric L.; DeVerter, Trent A.; Oehlschlaeger, Matthew A.; Kukkadapu, Goutham; Sung, Chih-Jen; Alrefae, Majed; Khaled, Fathi; Farooq, Aamir; Dirrenberger, Patricia; Glaude, Pierre-Alexandre Glaude; Battin-Leclerc, Frédérique; Santner, Jeffrey; Ju, Yiguang
Abstract:
Isobutene is an important intermediate in the pyrolysis and oxidation of higher-order branched alkanes, and it is also a component of commercial gasolines. To better understand its combustion characteristics, a series of ignition delay time (IDT) and laminar flame speed (LFS) measurements have been performed. In addition, flow reactor speciation data recorded for the pyrolysis and oxidation of isobutene is also reported. Predictions of an updated kinetic model described herein are compared with each of these data sets, as well as with existing jet-stirred reactor (JSR) species measurements.IDTs of isobutene oxidation were measured in four different shock tubes and in two rapid compression machines (RCMs) under conditions of relevance to practical combustors. The combination of shock tube and RCM data greatly expands the range of available validation data for isobutene oxidation models to pressures of 50 atm and temperatures in the range 666-1715 K. Isobutene flame speeds were measur...
http://hdl.handle.net/10379/6030
Marked
Mark
A comprehensive experimental and modeling study of isobutene oxidation
(2018)
Zhou, Chong-Wen; Li, Yang; O'Connor, Eoin; Somers, Kieran P.; Thion, Sébastien; Ke...
A comprehensive experimental and modeling study of isobutene oxidation
(2018)
Zhou, Chong-Wen; Li, Yang; O'Connor, Eoin; Somers, Kieran P.; Thion, Sébastien; Keesee, Charles; Mathieu, Olivier; Petersen, Eric L.; DeVerter, Trent A.; Oehlschlaeger, Matthew A.; Kukkadapu, Goutham; Sung, Chih-Jen; Alrefae, Majed; Khaled, Fathi; Farooq, Aamir; Dirrenberger, Patricia; Glaude, Pierre-Alexandre; Battin-Leclerc, Frédérique; Santner, Jeffrey; Ju, Yiguang
http://hdl.handle.net/10379/14536
Marked
Mark
A theoretical study of cyclic ether formation reactions
(2017)
Bugler, John; Power, Jennifer; Curran, Henry J.
A theoretical study of cyclic ether formation reactions
(2017)
Bugler, John; Power, Jennifer; Curran, Henry J.
Abstract:
Cyclisation reactions of hydroperoxyl-alkyl radicals forming cyclic ethers and hydroxyl radicals play an important role in low temperature oxidation chemistry. These reactions contribute to the competition be-tween radical chain propagation and chain branching reaction pathways which dominate the reactivity of alkanes at temperatures where negative temperature coefficient (NTC) behaviour is often observed. This work is motivated by previous experimental and modelling evidences that current literature rate coefficients for these reactions are in need of refinement and/or re-determination. In light of this, the current study presents quantum-chemically-derived high-pressure limit rate coefficients for all cyclisation reactions leading to cyclic ether formation in alkanes ranging in size from C-2 to C-5. Ro-vibrational properties of each stationary point were determined at the M06-2X/6-311 ++ G(d, p) level of theory. Coupled cluster (CCSD(T)) and Moller-Plesset perturbation theory (MP2...
http://hdl.handle.net/10379/6649
Marked
Mark
Critical evaluation of thermochemical properties of C-1-C-4 species: updated group-contributions to estimate thermochemical properties
(2016)
Burke, S. M.; Simmie, J. M.; Curran, Henry J.
Critical evaluation of thermochemical properties of C-1-C-4 species: updated group-contributions to estimate thermochemical properties
(2016)
Burke, S. M.; Simmie, J. M.; Curran, Henry J.
Abstract:
Journal article
A review of literature on enthalpies of formation and molar entropies for alkanes, alkenes, alcohols, hydroperoxides, and their associated radicals has been compiled and critically evaluated. By comparing literature values, the overall uncertainty in thermochemical properties of small hydrocarbons and oxygenated hydrocarbons can be highlighted. In general, there is good agreement between heat of formation values in the literature for stable species; however, there is greater uncertainty in the values for radical species and for molar entropy values. Updated values for a group-additivity method for the estimation of thermochemical properties based on the evaluated literature data are proposed. The new values can be used to estimate thermochemical data for larger, combustion-relevant species for which no calculations or measurements currently exist, with increased confidence. (C) 2015 AIP Publishing LLC.
http://hdl.handle.net/10379/6119
Marked
Mark
Low valence cation doping of bulk Cr2O3: Charge compensation and oxygen vacancy formation
(2016)
Carey, John J.; Legesse, Merid; Nolan, Michael
Low valence cation doping of bulk Cr2O3: Charge compensation and oxygen vacancy formation
(2016)
Carey, John J.; Legesse, Merid; Nolan, Michael
Abstract:
The different oxidation states of chromium allow its bulk oxide form to be reducible, facilitating the oxygen vacancy formation process, which is a key property in applications such as catalysis. Similar to other useful oxides such as TiO2, and CeO2, the effect of substitutional metal dopants in bulk Cr2O3 and its effect on the electronic structure and oxygen vacancy formation are of interest, particularly in enhancing the latter. In this paper, density functional theory (DFT) calculations with a Hubbard + U correction (DFT+U) applied to the Cr 3d and O 2p states, are carried out on pure and metal-doped bulk Cr2O3 to examine the effect of doping on the electronic and geometric structure. The role of dopants in enhancing the reducibility of Cr2O3 is examined to promote oxygen vacancy formation. The dopants are Mg, Cu, Ni, and Zn, which have a formal +2 oxidation state in their bulk oxides. Given this difference in host and, dopant oxidation states, we show that to predict the correct...
http://hdl.handle.net/10468/3201
Marked
Mark
The pyrolysis of 2-methylfuran: a quantum chemical, statistical rate theory and kinetic modelling study
(2016)
Somers, Kieran P.; Simmie, John M.; Metcalfe, Wayne K.; Curran, Henry J.
The pyrolysis of 2-methylfuran: a quantum chemical, statistical rate theory and kinetic modelling study
(2016)
Somers, Kieran P.; Simmie, John M.; Metcalfe, Wayne K.; Curran, Henry J.
Abstract:
Due to the rapidly growing interest in the use of biomass derived furanic compounds as potential platform chemicals and fossil fuel replacements, there is a simultaneous need to understand the pyrolysis and combustion properties of such molecules. To this end, the potential energy surfaces for the pyrolysis relevant reactions of the biofuel candidate 2-methylfuran have been characterized using quantum chemical methods (CBS-QB3, CBS-APNO and G3). Canonical transition state theory is employed to determine the high-pressure limiting kinetics, k(T), of elementary reactions. Rice-Ramsperger-Kassel-Marcus theory with an energy grained master equation is used to compute pressure-dependent rate constants, k(T, p), and product branching fractions for the multiple-well, multiple-channel reaction pathways which typify the pyrolysis reactions of the title species. The unimolecular decomposition of 2-methylfuran is shown to proceed via hydrogen atom transfer reactions through singlet carbene int...
http://hdl.handle.net/10379/6114
Marked
Mark
Theoretical and Kinetic Study of the Reaction of Ethyl Methyl Ketone with HO2 for T = 600 -1, 600 K. Part II: Addition Reaction Channels
(2013)
Zhou, Chong-Wen; Mendes, Jorge; Curran, Henry J.
Theoretical and Kinetic Study of the Reaction of Ethyl Methyl Ketone with HO2 for T = 600 -1, 600 K. Part II: Addition Reaction Channels
(2013)
Zhou, Chong-Wen; Mendes, Jorge; Curran, Henry J.
Abstract:
The temperature and pressure dependence of the addition reaction of ethyl methyl ketone (EMK) with HO2 radical has been calculated with the master equation method employing conventional transition state theory estimates for the microcanonical rate coefficients in the temperature range of 600-1600 K. Geometries, frequencies, and hindrance potentials were obtained at the B3LYP/6-311G(d,p) level of theory. A modified G3(MP2,CC) method has been used to calculate accurate electronic energies for all of the species involved in the reactions. The rigid-rotor harmonic oscillator approximation has been used for all of the vibrations except for the torsional degrees of freedom which are being treated as 1D hindered rotor. Asymmetric Eckart barriers were used to model tunneling effect in a one-dimensional reaction coordinate through saddle points. Our calculated results show that the four reaction channels forming 1-buten-2-ol + HÿO2 radical (R5), 2-buten-2-ol + HÿO2 radical (R10), acetic acid...
http://hdl.handle.net/10379/3412
Displaying Results 1 - 7 of 7 on page 1 of 1
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Institution
NUI Galway (6)
University College Cork (1)
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Peer-reviewed (6)
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2018 (1)
2017 (1)
2016 (4)
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