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Publication Linked Data and the Semantic Web Standards(Chapman and Hall / CRC Press, 2013) Hogan, Aidan; |~|On the traditional World Wide Web we all know and love, machines are used as brokers of content: they store, organize, request, route, transmit, receive and display content encapsulated as documents. In order for machines to process the content of documents automatically|for whatever purpose| they primarily require two things: machine-readable structure and semantics. Unfortunately, despite various advancements in the area of Natural Language Processing (NLP) down through the decades, modern computers still struggle to meaningfully process the idiosyncratic structure and semantics of natural language due to ambiguities present in grammar, coreference and word-sense.On the traditional World Wide Web we all know and love, machines are used as brokers of content: they store, organize, request, route, transmit, receive and display content encapsulated as documents. In order for machines to process the content of documents automatically|for whatever purpose| they primarily require two things: machine-readable structure and semantics. Unfortunately, despite various advancements in the area of Natural Language Processing (NLP) down through the decades, modern computers still struggle to meaningfully process the idiosyncratic structure and semantics of natural language due to ambiguities present in grammar, coreference and word-sense. Hence, machines require a more \formal" notion of structure and semantics using unambiguous grammar, referencing and vocabulary.Publication 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.; SFIThe 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 + ethylene + ÿO H radical (R13), 2-methyl-2-oxetanol + ÿOH radical (R15) are the dominant channels. When the temperature is below 1000 K, the reaction R15 forming the cyclic ether, 2-methyl-2-oxetanol, is dominant; while the reaction R13 forming acetic acid + ethylene + ÿOH radical becomes increasingly dominant at temperatures above 1000 K. The other two channels forming 1-buten-2-ol, 2-buten-2-ol and HO2 radical are not dominant but are still important product channels over the whole temperature range investigated here. No pressure dependence has been found for the reaction channels forming 2-methyl-2-oxetanol + OH radical and acetic acid + ethylene + OH radical. A slightly negative pressure dependence has been found for the reaction channels producing the two butenols. Rate constants for the four important reaction channels at 1 atm (in cm3mol-1s-1) are: kR5 = 2.67 × 1015 × T-1.32 exp(-16637/T ) kR10 = 1.62 × 108 × T 0.57 exp(-13142/T ) kR13 = 2.29 × 1017 × T-1.66 exp(-18169/T ) kR15 = 6.17 × 10-2 × T 3.35 exp(-10136/T ) A comparison of the total rate constants for the addition of HO2 radical to EMK and that for H-atom abstraction by HO2 radical from EMK has also been carried out. We find that the abstraction reaction channels are dominant over the entire temperature range of 600-1600 K.Publication Theoretical and Kinetic Study of the Reactions of Ketones with HO(2) Radicals. Part I: Abstraction Reaction Channels.(2013) Mendes, Jorge; Zhou, Chong-Wen; Curran, Henry J.; SFIThis work presents an ab-initio and chemical kinetic study of the reaction mechanisms of hydrogen atom abstraction by the HO2 radical on five ketones: dimethyl, ethyl methyl, n-propyl methyl, iso-propyl methyl and iso-butyl methyl ketones. The Moller-Plesset method with 6-311G(d,p) basis set has been used in the geometry optimization and the frequency calculation for all the species involved in the reactions, as well as the hindrance potential description for reactants and transition states. Intrinsic reaction co-ordinate calculations were carried out to validate all the connections between transition states and local minima. Energies are reported at the CCSD(T)/cc-pVTZ//MP2/6-311G(d,p) level of theory. The CCSD(T)/cc-pVXZ method (X = D, T, Q) was used for the reaction mechanism of dimethyl ketone + HO2 radical in order to benchmark the computationally less expensive method of CCSD(T)/cc-pVTZ//MP2/6-311G(d,p). High-pressure limit rate constants have been calculated for all the reaction channels by conventional transition state theory with Eckart tunneling corrections and 1-D hindered rotor approximations in the temperature range 500-2000 K.