Bio


Education
University of Toronto Physics B.S (1978)
University of Toronto Aerospace Sciences M.Sc. (1980)
York University Physics Ph.D. (1986)

Appointment:
1986-present Senior Research Engineer, Mechanical Engineering Department

Research Activities:
Dr. Davidson’s research interests span the fields of gas dynamics and combustion kinetics. During his tenure at Stanford University he investigated the chemical kinetics of combustion using a wide array of optical and laser-based diagnostic methods and advanced the use of these diagnostics in shock tubes. He co-authored over 350 research publications with his students and Professor Ronald Hanson. He continues to advise and mentor the graduate students who use shock tubes in the High Temperature Gasdynamics Laboratories. An overview of the shock tube studies performed at Stanford under Prof. Hanson’s and Dr. Davidson’s supervision can be found in the report entitled “Fundamental Kinetics Database Utilizing Shock Tube Measurements” available at http://purl.stanford.edu/kb621cw6967.
He claims he is now retired, but apparently, he is still working.

Academic Appointments


  • Sr Research Engineer, Mechanical Engineering

Stanford Advisees


  • Doctoral Dissertation Reader (NonAC)
    Taylor Rault

All Publications


  • Shock tube/laser absorption measurement of the rate constant of the reaction: H 2 O 2+CO 2 2OH+CO 2 PROCEEDINGS OF THE COMBUSTION INSTITUTE Shao, J., Choudhary, R., Davidson, D. F., Hanson, R. K. 2023; 39 (1): 735-743
  • Low-temperature oxidation of n-octane and n-decane in shock tubes: Differences in time histories of key intermediates COMBUSTION AND FLAME Choudhary, R., Clees, S., Boddapati, V., Shao, J., Davidson, D. F., Hanson, R. K. 2023; 251
  • NOx formation from ammonia, and its effects on oxy-combustion of hydrocarbon fuels under supercritical-CO2 conditions APPLICATIONS IN ENERGY AND COMBUSTION SCIENCE Gokulakrishnan, P., Shao, J., Klassen, M. S., Davidson, D. F., Hanson, R. K. 2023; 13
  • A mid-IR laser absorption diagnostic for measuring formaldehyde at high pressures and its demonstration in shock tubes COMBUSTION AND FLAME Biswas, P., Choudhary, R., Panda, A., Davidson, D. F., Hanson, R. K. 2022; 245
  • Shock Tube/Laser Absorption Measurements of Cyclopentadiene Pyrolysis. The journal of physical chemistry. A Johnson, S. E., Davidson, D. F., Hanson, R. K. 2022

    Abstract

    High-temperature cyclopentadiene pyrolysis was examined behind reflected shock waves in a heated shock tube using several laser absorption diagnostic schemes. A two-color, online-offline sensor near 3335 cm-1 was used to measure time histories of acetylene, while a three-color scheme of diagnostics at 10.532, 10.675, and 11.345 mum yielded measurements of cyclopentadiene and ethylene. Species time histories of cyclopentadiene decomposition and acetylene formation as well as ethylene yields are reported from 1319 to 1678 K at 1.2-1.5 atm. In addition, the overall decomposition rate of cyclopentadiene is reported, and comparisons are made to a number of kinetic models.

    View details for DOI 10.1021/acs.jpca.2c04381

    View details for PubMedID 35853207

  • Shock tube/laser absorption measurements of the isomerization rates of allene and propyne COMBUSTION AND FLAME Johnson, S. E., Ding, Y., Davidson, D. F., Hanson, R. K. 2022; 238
  • Shock tube study of ethanol pyrolysis II: Rate constant measurements and modeling COMBUSTION AND FLAME Choudhary, R., Boddapati, V., Clees, S., Girard, J. J., Peng, Y., Shao, J., Davidson, D. F., Hanson, R. K. 2021; 233
  • Shock tube study of ethanol pyrolysis I: Multi-species time-history measurements COMBUSTION AND FLAME Choudhary, R., Boddapati, V., Clees, S., Girard, J. J., Peng, Y., Shao, J., Davidson, D. F., Hanson, R. K. 2021; 233
  • Experimental and modeling of autoignition of gaseous hydrocarbon fuels in the presence of H2 and C2H4 FUEL Gokulakrishnan, P., Fuller, C., Klassen, M., Davidson, D., Hanson, R. 2021; 296
  • Collisional excitation kinetics for O(3s S-5(o)) and O(3p P-5(3)) states using laser absorption spectroscopy in shock-heated weakly ionized O-2-Ar mixture PHYSICAL REVIEW E Li, Y., Wang, Y., Davidson, D. F., Hanson, R. K. 2021; 103 (6)
  • Collisional excitation kinetics for O(3s^{5}S^{o}) and O(3p^{5}P_{3}) states using laser absorption spectroscopy in shock-heated weakly ionized O_{2}-Ar mixture. Physical review. E Li, Y., Wang, Y., Davidson, D. F., Hanson, R. K. 2021; 103 (6-1): 063211

    Abstract

    Collisional excitation kinetics for atomic oxygen is studied behind reflected shock waves in 1%O_{2}/Ar mixtures over 10 000-11 000K using laser absorption spectroscopy of the O(3s^{5}S^{o}) to O(3p^{5}P_{3}) transition at 777 nm and the O(3p^{5}P_{3}) to O(3d ^{5}D_{2,3,4}^{o}) transitions at 926 nm. Four time histories are inferred simultaneously from the absorbance of the two transitions: the population density of level 4 of atomic oxygen, i.e., the O(3s ^{5}S^{o}) state, n_{4}; the population density of level 6 of atomic oxygen, i.e., the O(3p^{5}P_{3}) state, n_{6}; the electron number density, n_{e}; and the heavy-particle translational temperature, T_{tr}. Atomic oxygen in the levels 4 and 6 are not in equilibrium with the ground-state atomic oxygen as the measurements of n_{4} and n_{6} are generally 3-20 times smaller than the corresponding values under Boltzmann equilibrium at T_{tr}. However, these two states are close to partial equilibrium with each other within the test time, indicating strong heavy-particle cross coupling between levels 4 and 6 of atomic oxygen. A simplified two-temperature collisional-radiative (CR) model is developed to study the thermal and chemical nonequilibrium of atomic oxygen following shock heating. The four measured time histories are used to optimize the 12 collisional rate constants in the CR model using a stochastic gradient descent (SGD) algorithm. The time-history results, diagnostic methods, and collisional-radiative model presented in the current study are potentially useful in studies of high-enthalpy air, plasma processing, or other applications involving weakly ionized oxygen.

    View details for DOI 10.1103/PhysRevE.103.063211

    View details for PubMedID 34271738

  • Scientific accomplishments and research avenues of Professor Ronald Hanson COMBUSTION AND FLAME Davidson, D. F., Jeffries, J. B., Oehlschlaeger, M. A., Strand, C. L. 2021; 224: 2–5
  • Measurement of time histories of stable intermediates during first stage ignition of n-heptane and its two isomers in a shock tube PROCEEDINGS OF THE COMBUSTION INSTITUTE Choudhary, R., Girard, J. J., Clees, S., Johnson, S. E., Shao, J., Davidson, D. F., Hanson, R. K., Aradi, A. A. 2021; 38 (1): 957-965
  • High-speed imaging of n-heptane ignition in a high-pressure shock tube PROCEEDINGS OF THE COMBUSTION INSTITUTE Shao, J., Choudhary, R., Susa, A. J., Davidson, D. F., Hanson, R. K. 2021; 38 (1): 911-918
  • Shock-induced ignition and pyrolysis of high-pressure methane and natural gas mixtures COMBUSTION AND FLAME Shao, J., Ferris, A. M., Choudhary, R., Cassady, S. J., Davidson, D. F., Hanson, R. K. 2020; 221: 364–70
  • A physics-based approach to modeling real-fuel combustion chemistry - VI. Predictive kinetic models of gasoline fuels COMBUSTION AND FLAME Xu, R., Saggese, C., Lawson, R., Movaghar, A., Parise, T., Shao, J., Choudhary, R., Park, J., Lu, T., Hanson, R. K., Davidson, D. F., Egolfopoulos, F. N., Aradi, A., Prakash, A., Mohan, V., Cracknell, R., Wang, H. 2020; 220: 475–87
  • The pyrolysis of propane INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Cassady, S. J., Choudhary, R., Boddapati, V., Pinkowski, N. H., Davidson, D. F., Hanson, R. K. 2020

    View details for DOI 10.1002/kin.21395

    View details for Web of Science ID 000540365200001

  • Shock tube/laser absorption measurements of the pyrolysis of JP-10 fuel COMBUSTION AND FLAME Johnson, S. E., Davidson, D. F., Hanson, R. K. 2020; 216: 161–73
  • Spectroscopic inference of alkane, alkene, and aromatic formation during high-temperature JP8, JP5, and Jet-A pyrolysis FUEL Pinkowski, N. H., Cassady, S. J., Davidson, D. F., Hanson, R. K. 2020; 269
  • Determination of the JP10 + OH → Product Reaction Rate with Measured Fuel Concentrations in Shock Tube Experiments. The journal of physical chemistry. A Zaczek, L. T., Davidson, D. F., Hanson, R. K. 2020

    Abstract

    The overall reaction rate for JP10 + OH → products was measured directly via laser absorption of OH in shock tube experiments from 931 to 1308 K and 0.94 to 1.44 atm. The JP10 concentration of test gas mixtures was measured in the shock tube for several experiments using a 3.39 μm laser fuel diagnostic. The measured JP10 concentrations indicated fuel losses due to adsorption of 11-31% compared to values calculated manometrically from mixture preparation. OH was generated via rapid thermal decomposition of tert-butyl hydroperoxide behind reflected shock waves, and post-shock OH profiles were measured via laser absorption at 308.6 nm. The measured OH profiles were fit with a chemical kinetic model for JP10 chemistry to determine the overall JP10 + OH reaction rate. A recommendation is made for the JP10 + OH overall reaction rate over the temperature range explored in this study as k1 (931-1308 K) = 1.622 × 1014 exp(-1826/T [K]) ± 12%. To the authors' knowledge, these data are the first direct measurements of the overall reaction rate for JP10 + OH.

    View details for DOI 10.1021/acs.jpca.0c00065

    View details for PubMedID 32178517

  • The Thermal Decomposition of Ethane Fuel Cassady, S. J., Choudhary, R., Pinkowski, N. H., Shao, J., Davidson, D. F., Hanson, R. K. 2020
  • Shock Tube Measurement of the CH3 + C2H6 CH4 + C2H5 Rate Constant. The journal of physical chemistry. A Shao, J., Wei, W., Choudhary, R., Davidson, D. F., Hanson, R. K. 2019

    Abstract

    The rate constant for the CH3 + C2H6 CH4 + C2H5 reaction was studied behind reflected shock waves at temperatures between 1369 and 1626 K and pressures from 8.6 to 47.4 atm in mixtures of methane, ethane, and argon. Ethylene time histories were measured using laser absorption of radiation from a carbon dioxide gas laser near 10.532 mum. The resulting rate constant data can be represented by the Arrhenius equation k (T) = 3.90 * 1013 exp(-16670 cal/mol/RT) cm3 mol-1 s-1. We believe this is the first study to extend experimental data for this rate constant to temperatures above 1400 K. The overall 2sigma uncertainty of the current data is +18%/-21% resulting primarily from uncertainties associated with the influence of secondary reactions and the fitting of rapidly changing species time histories at the higher temperatures.

    View details for DOI 10.1021/acs.jpca.9b07691

    View details for PubMedID 31557027

  • Experimental Observation of Negative Temperature Dependence in iso-Octane Burning Velocities Susa, A. J., Ferris, A. M., Davidson, D. E., Hanson, R. K. AMER INST AERONAUTICS ASTRONAUTICS. 2019: 4476–81

    View details for DOI 10.2514/1.J058530

    View details for Web of Science ID 000493056400033

  • Gravity-current-induced test gas stratification and its prevention in constrained reaction volume shock-tube experiments SHOCK WAVES Susa, A. J., Davidson, D. F., Hanson, R. K. 2019; 29 (7): 969–84
  • High-temperature laminar flame speed measurements in a shock tube COMBUSTION AND FLAME Ferris, A. M., Susa, A. J., Davidson, D. F., Hanson, R. K. 2019; 205: 241–52
  • Multi-wavelength speciation of high-temperature 1-butene pyrolysis FUEL Pinkowski, N. H., Cassady, S. J., Davidson, D. F., Hanson, R. K. 2019; 244: 269–81
  • A shock tube study of n-heptane, iso-octane, n-dodecane and iso-octane/n-dodecane blends oxidation at elevated pressures and intermediate temperatures FUEL Shao, J., Choudhary, R., Peng, Y., Davidson, D. F., Hanson, R. K. 2019; 243: 541–53
  • Measurement of the reaction rate of H + O-2 + M -> HO2 + M, for M=Ar, N-2, CO2, at high temperature with a sensitive OH absorption diagnostic COMBUSTION AND FLAME Choudhary, R., Girard, J. J., Peng, Y., Shao, J., Davidson, D. F., Hanson, R. K. 2019; 203: 265–78
  • A new method of estimating derived cetane number for hydrocarbon fuels FUEL Wang, Y., Cao, Y., Wei, W., Davidson, D. F., Hanson, R. K. 2019; 241: 319–26
  • A multi-wavelength speciation framework for high-temperature hydrocarbon pyrolysis JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Pinkowski, N. H., Ding, Y., Johnson, S. E., Wang, Y., Parise, T. C., Davidson, D. F., Hanson, R. K. 2019; 225: 180–205
  • Shock Tube Measurement of the C2H4 + H double left right arrow C2H3 + H-2 Rate Constant JOURNAL OF PHYSICAL CHEMISTRY A Shao, J., Choudhary, R., Peng, Y., Davidson, D. F., Hanson, R. K. 2019; 123 (1): 15–20

    Abstract

    The rate constant for the reaction C2H4+H⇒C2H3+H2 was studied behind reflected shock waves at temperatures between 1619 and 1948 K and pressures near 10 atm in a mixture of C2H4, CH4, H2, and argon. C2H4 time-histories were measured using laser absorption of a CO2 gas laser near 10.53 microns. Experimental mixtures were designed to optimize sensitivity to the title reaction with only weak sensitivity to secondary reactions. Two mechanisms, FFCM1 and ARAMCO v2, are used for data analysis. The well-selected operating conditions and Monte-Carlo Sampling data analysis procedure resulted in mechanism independent reaction rate constant measurements with 2σ uncertainty of +/-35 %. The current data disagree with a broadly used theoretical calculation (Knyazev et al. (1996)), but they are in good consensus with one of the review studies (Baulch et al. (2005)), k=3.9×1022T3.62exp(-5670/T) cm3molecule-1s-1. To the best of our knowledge, this work provides the first high temperature study of C2H4+H⇒C2H3+H2 reaction rate constant with well-defined uncertainty.

    View details for PubMedID 30537818

  • Shock tube study of the rate constants for H +O-2 + M -> HO2 +M (M = Ar, H2O, CO2, N-2) at elevated pressures PROCEEDINGS OF THE COMBUSTION INSTITUTE Shao, J., Choudhary, R., Susa, A., Davidson, D. F., Hanson, R. K. 2019; 37 (1): 145–52
  • On estimating physical and chemical properties of hydrocarbon fuels using mid-infrared FTIR spectra and regularized linear models Fuel Wang, Y., Ding, Y., Wei, W., Cao, Y., Davidson, D. F., Hanson, R. K. 2019; 255: 115715
  • Ignition delay times of methane and hydrogen highly diluted in carbon dioxide at high pressures up to 300 atm PROCEEDINGS OF THE COMBUSTION INSTITUTE Shao, J., Choudhary, R., Davidson, D. E., Hanson, R. K., Barak, S., Vasu, S. 2019; 37 (4): 4555–62
  • Ignition delay time measurements and modeling for gasoline at very high pressures PROCEEDINGS OF THE COMBUSTION INSTITUTE Davidson, D. F., Shao, J. K., Choudhary, R., Mehl, M., Obrecht, N., Hanson, R. K. 2019; 37 (4): 4885–92
  • A streamlined approach to hybrid-chemistry modeling for a low cetane-number alternative jet fuel Combustion and Flame Pinkowski, N. H., Wang, Y., Cassady, S. J., Davidson, D. F., Hanson, R. K. 2019; 208: 15-26
  • A comparative laser absorption and gas chromatography study of low-temperature n-heptane oxidation intermediates PROCEEDINGS OF THE COMBUSTION INSTITUTE Ferris, A. M., Susa, A. J., Davidson, D. F., Hanson, R. K. 2019; 37 (1): 249–57
  • Shock tube measurements of OH concentration time-histories in benzene, toluene, ethylbenzene and xylene oxidation PROCEEDINGS OF THE COMBUSTION INSTITUTE Wang, S., Davidson, D. F., Hanson, R. K. 2019; 37 (1): 163–70
  • A Physics-based approach to modeling real-fuel combustion chemistry - III. Reaction kinetic model of JP10 COMBUSTION AND FLAME Tao, Y., Xu, R., Wang, K., Shao, J., Johnson, S. E., Movaghar, A., Han, X., Park, J., Lu, T., Brezinsky, K., Egolfopoulos, F. N., Davidson, D. F., Hanson, R. K., Bowman, C. T., Wang, H. 2018; 198: 466–76
  • Shock tube study of normal heptane first-stage ignition near 3.5 atm COMBUSTION AND FLAME Campbell, M. F., Wang, S., Davidson, D. F., Hanson, R. K. 2018; 198: 376–92
  • A physics based approach to modeling real-fuel combustion chemistry - IV. HyChem modeling of combustion kinetics of a bio-derived jet fuel and its blends with a conventional Jet A COMBUSTION AND FLAME Wang, K., Xu, R., Parise, T., Shao, J., Movaghar, A., Lee, D., Park, J., Gao, Y., Lu, T., Egolfopoulos, F. N., Davidson, D. F., Hanson, R. K., Bowman, C. T., Wang, H. 2018; 198: 477–89
  • A combined laser absorption and gas chromatography sampling diagnostic for speciation in a shock tube COMBUSTION AND FLAME Ferris, A. M., Davidson, D. E., Hanson, R. K. 2018; 195: 40–49
  • High-speed imaging of inhomogeneous ignition in a shock tube Tulgestke, A. M., Johnson, S. E., Davidson, D. F., Hanson, R. K. SPRINGER. 2018: 1089–95
  • A shock tube study of jet fuel pyrolysis and ignition at elevated pressures and temperatures FUEL Shao, J., Zhu, Y., Wang, S., Davidson, D. F., Hanson, R. K. 2018; 226: 338–44
  • A shock tube study of ignition delay times in diluted methane, ethylene, propene and their blends at elevated pressures FUEL Shao, J., Davidson, D. F., Hanson, R. K. 2018; 225: 370–80
  • A physics-based approach to modeling real-fuel combustion chemistry - II. Reaction kinetic models of jet and rocket fuels COMBUSTION AND FLAME Xu, R., Wang, K., Banerjee, S., Shao, J., Parise, T., Zhu, Y., Wang, S., Movaghar, A., Lee, D., Zhao, R., Han, X., Gao, Y., Lu, T., Brezinsky, K., Egolfopoulos, F. N., Davidson, D. F., Hanson, R. K., Bowman, C. T., Wang, H. 2018; 193: 520–37
  • A physics-based approach to modeling real-fuel combustion chemistry - I. Evidence from experiments, and thermodynamic, chemical kinetic and statistical considerations COMBUSTION AND FLAME Wang, H., Xu, R., Wang, K., Bowman, C. T., Hanson, R. K., Davidson, D. F., Brezinsky, K., Egolfopoulos, F. N. 2018; 193: 502–19
  • Development of a two-wavelength IR laser absorption diagnostic for propene and ethylene MEASUREMENT SCIENCE AND TECHNOLOGY Parise, T. C., Davidson, D. F., Hanson, R. K. 2018; 29 (5)
  • A new diagnostic for hydrocarbon fuels using 3.41-mu m diode laser absorption COMBUSTION AND FLAME Wang, S., Parise, T., Johnson, S. E., Davidson, D. F., Hanson, R. K. 2017; 186: 129–39
  • Shock Tube and Laser Absorption Study of CH2O Oxidation via Simultaneous Measurements of OH and CO. The journal of physical chemistry. A Wang, S., Davidson, D. F., Hanson, R. K. 2017; 121 (45): 8561-8568

    Abstract

    The oxidation of Ar-diluted stoichiometric CH2O-O2 mixtures was studied behind reflected shock waves over temperatures of 1332-1685 K, at pressures of about 1.5 atm and initial CH2O mole fractions of 500, 1500, and 5000 ppm. Quantitative and time-resolved concentration histories of OH and CO (at both v″ = 0 and v″ = 1) were measured by narrow-linewidth laser absorption at 306.7 and 4854 nm, respectively. A time delay was observed between the formation of v″ = 0 and v″ = 1 states of CO, suggesting that CO was kinetically generated primarily in the ground state and then collisionally relaxed toward vibrational equilibrium. The measured CO and OH time-histories were used to evaluate the performance of four detailed reaction mechanisms regarding the oxidation chemistry of CH2O. Further analyses of these time-history data have also led to improved determination for the rate constants of two key reactions, namely H + O2 = O + OH (R1) and OH + CO = CO2 + H (R2), as follows: k1 = 8.04 × 1013 exp(-7370 K/T) cm3 mol-1 s-1, k2 = 1.90 × 1012 exp(-2760 K/T) cm3 mol-1 s-1; both expressions are valid over 1428-1685 K and have 1σ uncertainties of approximately ±10%.

    View details for DOI 10.1021/acs.jpca.7b09362

    View details for PubMedID 29065683

  • Chemical kinetic modeling and shock tube study of methyl propanoate decomposition COMBUSTION AND FLAME Ning, H., Wu, J., Ma, L., Ren, W., Davidson, D. F., Hanson, R. K. 2017; 184: 30–40
  • Toward a better understanding of 2-butanone oxidation: Detailed species measurements and kinetic modeling COMBUSTION AND FLAME Hemken, C., Burke, U., Lam, K., Davidson, D. F., Hanson, R. K., Heufer, K., Kohse-Hoeinghaus, K. 2017; 184: 195–207
  • Dependence of Calculated Postshock Thermodynamic Variables on Vibrational Equilibrium and Input Uncertainty JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Campbell, M. F., Owen, K. G., Davidson, D. F., Hanson, R. K. 2017; 31 (3): 586–608

    View details for DOI 10.2514/1.T4952

    View details for Web of Science ID 000405487900009

  • Time-resolved sub-ppm CH3 detection in a shock tube using cavity-enhanced absorption spectroscopy with a ps-pulsed UV laser PROCEEDINGS OF THE COMBUSTION INSTITUTE Wang, S., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2017; 36 (3): 4549-4556
  • Combined Ab Initio, Kinetic Modeling, and Shock Tube Study of the Thermal Decomposition of Ethyl Formate. The journal of physical chemistry. A Ning, H. n., Wu, J. n., Ma, L. n., Ren, W. n., Davidson, D. F., Hanson, R. K. 2017; 121 (35): 6568–79

    Abstract

    The potential energy surfaces (PESs) and reaction rate constants of the unimolecular decomposition of ethyl formate (EF) were investigated using high-precision theoretical methods at the CCSD(T)/CBS(T-Q)//M06-2X/6-311++G(d,p) level of theory. The calculated PESs of EF dissociation and molecular decomposition reactions indicate that the intramolecular H-shift to produce formic acid and ethylene is the dominant decomposition pathway. A detailed chemical kinetic mechanism for EF pyrolysis was constructed by incorporating the important reactions of EF and its radicals into an existing mechanism previously developed for small methyl esters. The updated mechanism was first used to reproduce CO, CO2, and H2O concentration time histories during EF pyrolysis in the shock tube reported by Ren et al. [ Ren , W. , Mitchell Spearrin , R. , Davidson , D. F. , and Hanson , R. K. J. Phys. Chem. A 2014 , 118 , 1785 - 1798 ]. The rate of production and sensitivity analyses show that the competing dehydration and decarboxylation channels of the intermediate formic acid control the final product yields of EF pyrolysis. The EF mechanism was further validated against the shock tube data of OH, CO, CO2, and H2O time histories measured during EF oxidation (equivalence ratio Φ = 1.0) at 1331-1615 K and 1.52-1.74 atm. This revised EF mechanism captured all of the species' time histories over the entire temperature range. Such modeling capability was due to the more accurate rate constants of EF reactions determined by high-precision theoretical calculations and a high-fidelity C0-C2 basis mechanism.

    View details for PubMedID 28792750

  • Shock tube/laser absorption measurements of the pyrolysis of a bimodal test fuel PROCEEDINGS OF THE COMBUSTION INSTITUTE Parise, T., Davidson, D. F., Hanson, R. K. 2017; 36 (1): 281-288
  • Pyrolysis and oxidation of methyl acetate in a shock tube: A multi-species time-history study PROCEEDINGS OF THE COMBUSTION INSTITUTE Ren, W., Lam, K., Davidson, D. F., Hanson, R. K., Yang, X. 2017; 36 (1): 255-264
  • Rate constants of long, branched, and unsaturated aldehydes with OH at elevated temperatures PROCEEDINGS OF THE COMBUSTION INSTITUTE Wang, S., Davidson, D. F., Hanson, R. K. 2017; 36 (1): 151-160
  • Ignition delay time correlations for distillate fuels FUEL Davidson, D. F., Zhu, Y., Shao, J., Hanson, R. K. 2017; 187: 26-32
  • Kinetics of Excited Oxygen Formation in Shock-Heated O-2-Ar Mixtures JOURNAL OF PHYSICAL CHEMISTRY A Nations, M., Wang, S., Goldenstein, C. S., Davidson, D. F., Hanson, R. K. 2016; 120 (42): 8234-8243
  • Kinetics of Excited Oxygen Formation in Shock-Heated O2-Ar Mixtures. journal of physical chemistry. A Nations, M., Wang, S., Goldenstein, C. S., Davidson, D. F., Hanson, R. K. 2016: -?

    Abstract

    The formation of electronically excited atomic oxygen was studied behind reflected shock waves using cavity-enhanced absorption spectroscopy. Mixtures of 1% O2-Ar were shock-heated to 5400-7500 K, and two distributed-feedback diode lasers near 777.2 and 844.6 nm were used to measure time-resolved populations of atomic oxygen's (5)S° and (3)S° electronic states, respectively. Measurements were compared with simulated population time histories obtained using two different kinetic models that accounted for thermal nonequilibrium effects: (1) a multitemperature model and (2) a reduced collisional-radiative model. The former assumed a Boltzmann distribution of electronic energy, whereas the latter allowed for non-Boltzmann populations by treating the probed electronic states as pseudospecies and accounting for dominant electronic excitation/de-excitation processes. The effects of heavy-particle collisions were investigated and found to play a major role in the kinetics of O atom electronic excitation at the conditions studied. For the first time, rate constants (kM) for O atom electronic excitation from the ground state ((3)P) due to collisions with argon atoms were directly inferred using the reduced collisional-radiative model, kM((3)P → (5)S°) = 7.8 × 10(-17)T(0.5) exp(-1.061 × 10(5)K/T) ± 25% cm(3) s(-1) and kM((3)P → (3)S°) = 2.5 × 10(-17)T(0.5) exp(-1.105 × 10(5)K/T) ± 25% cm(3) s(-1).

    View details for PubMedID 27689820

  • Oxygen Vibrational Relaxation Times: Shock Tube/Laser Absorption Measurements JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Owen, K. G., Davidson, D. F., Hanson, R. K. 2016; 30 (4): 791-798

    View details for DOI 10.2514/1.T4505

    View details for Web of Science ID 000387338000001

  • Shock Tube Measurement for the Dissociation Rate Constant of Acetaldehyde Using Sensitive CO Diagnostics. journal of physical chemistry. A Wang, S., Davidson, D. F., Hanson, R. K. 2016; 120 (35): 6895-6901

    Abstract

    The rate constant of acetaldehyde thermal dissociation, CH3CHO = CH3 + HCO, was measured behind reflected shock waves at temperatures of 1273-1618 K and pressures near 1.6 and 0.34 atm. The current measurement utilized sensitive CO diagnostics to track the dissociation of CH3CHO via oxygen atom balance and inferred the title rate constant (k1) from CO time histories obtained in pyrolysis experiments of 1000 and 50 ppm of CH3CHO/Ar mixtures. By using dilute test mixtures, the current study successfully suppressed the interferences from secondary reactions and directly determined the title rate constant as k1(1.6 atm) = 1.1 × 10(14) exp(-36 700 K/T) s(-1) over 1273-1618 K and k1(0.34 atm) = 5.5 × 10(12) exp(-32 900 K/T) s(-1) over 1377-1571 K, with 2σ uncertainties of approximately ±30% for both expressions. Example simulations of existing reaction mechanisms updated with the current values of k1 demonstrated substantial improvements with regards to the acetaldehyde pyrolysis chemistry.

    View details for DOI 10.1021/acs.jpca.6b03647

    View details for PubMedID 27523494

  • Improved Shock Tube Measurement of the CH4 + Ar = CH3 + H + Ar Rate Constant using UV Cavity-Enhanced Absorption Spectroscopy of CH3. journal of physical chemistry. A Wang, S., Davidson, D. F., Hanson, R. K. 2016; 120 (28): 5427-5434

    Abstract

    We report an improved measurement for the rate constant of methane dissociation in argon (CH4 + Ar = CH3 + H + Ar) behind reflected shock waves. The experiment was conducted using a sub-parts per million sensitivity CH3 diagnostic recently developed in our laboratory based on ultraviolet cavity-enhanced absorption spectroscopy. The high sensitivity of this diagnostic allowed for measurements of quantitatively resolved CH3 time histories during the initial stage of CH4 pyrolysis, where the reaction system is clean and free from influences of secondary reactions and temperature change. This high sensitivity also allowed extension of our measurement range to much lower temperatures (<1500 K). The current-reflected shock measurements were performed at temperatures between 1487 and 1866 K and pressures near 1.7 atm, resulting in the following Arrhenius rate constant expression for the title reaction: k(1.7 atm) = 3.7 × 10(16) exp(-42 200 K/T) cm(3)/mol·s, with a 2σ uncertainty factor of 1.25. The current data are in good consensus with various theoretical and review studies, but at the low temperature end they suggest a slightly higher (up to 35%) rate constant compared to these previous results. A re-evaluation of previous and current experimental data in the falloff region was also performed, yielding updated expressions for both the low-pressure limit and the high-pressure limit rate constants and improved agreement with all existing data.

    View details for DOI 10.1021/acs.jpca.6b02572

    View details for PubMedID 27380878

  • AEROFROSH: a shock condition calculator for multi-component fuel aerosol-laden flows SHOCK WAVES Campbell, M. F., Haylett, D. R., Davidson, D. F., Hanson, R. K. 2016; 26 (4): 429-447
  • Measurements of Oxygen Dissociation Using Laser Absorption JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER Owen, K. G., Davidson, D. F., Hanson, R. K. 2016; 30 (2): 274-278

    View details for DOI 10.2514/1.T4506

    View details for Web of Science ID 000374863100003

  • High-speed OH* chemiluminescence imaging of ignition through a shock tube end-wall APPLIED PHYSICS B-LASERS AND OPTICS Troutman, V. A., Strand, C. L., Campbell, M. F., Tulgestke, A. M., Miller, V. A., Davidson, D. F., Hanson, R. K. 2016; 122 (3)
  • Scaling relation for high-temperature biodiesel surrogate ignition delay times FUEL Campbell, M. F., Davidson, D. F., Hanson, R. K. 2016; 164: 151-159
  • Cavity-enhanced absorption spectroscopy with a ps-pulsed UV laser for sensitive, high-speed measurements in a shock tube OPTICS EXPRESS Wang, S., Sun, K., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2016; 24 (1): 308-318
  • Strategies for obtaining long constant-pressure test times in shock tubes SHOCK WAVES Campbell, M. F., Parise, T., Tulgestke, A. M., Spearrin, R. M., Davidson, D. F., Hanson, R. K. 2015; 25 (6): 651-665
  • Shock-tube measurements of excited oxygen atoms using cavity-enhanced absorption spectroscopy APPLIED OPTICS Nations, M., Wang, S., Goldenstein, C. S., Sun, K., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2015; 54 (29): 8766-8775

    Abstract

    We report the use of cavity-enhanced absorption spectroscopy (CEAS) using two distributed feedback diode lasers near 777.2 and 844.6 nm for sensitive, time-resolved, in situ measurements of excited-state populations of atomic oxygen in a shock tube. Here, a 1% O2/Ar mixture was shock-heated to 5400-8000 K behind reflected shock waves. The combined use of a low-finesse cavity, fast wavelength scanning of the lasers, and an off-axis alignment enabled measurements with 10 μs time response and low cavity noise. The CEAS absorption gain factors of 104 and 142 for the P35←S520 (777.2 nm) and P0,1,23←S310 (844.6 nm) atomic oxygen transitions, respectively, significantly improved the detection sensitivity over conventional single-pass measurements. This work demonstrates the potential of using CEAS to improve shock-tube studies of nonequilibrium electronic-excitation processes at high temperatures.

    View details for DOI 10.1364/AO.54.008766

    View details for Web of Science ID 000362667200028

    View details for PubMedID 26479817

  • Shock Tube Measurement of the High-Temperature Rate Constant for OH + CH3 -> Products JOURNAL OF PHYSICAL CHEMISTRY A Wang, S., Li, S., Davidson, D. F., Hanson, R. K. 2015; 119 (33): 8799-8805
  • Shock Tube Measurement of the High-Temperature Rate Constant for OH + CH3 → Products. The journal of physical chemistry. A Wang, S., Li, S., Davidson, D. F., Hanson, R. K. 2015; 119 (33): 8799-805

    Abstract

    The reaction between hydroxyl (OH) and methyl radicals (CH3) is critical to hydrocarbon oxidation. Motivated by the sparseness of its high-temperature rate constant data and the large uncertainties in the existing literature values, the current study has remeasured the overall rate constant of the OH + CH3 reaction and extended the measurement temperature range to 1214-1933 K, using simultaneous laser absorption diagnostics for OH and CH3 radicals behind incident and reflected shock waves. tert-Butyl hydroperoxide and azomethane were used as pyrolytic sources for the OH and CH3 radicals, respectively. The current study bridged the temperature ranges of existing experimental data, and good agreement is seen between the current measurement and some previous experimental and theoretical high-temperature studies. A recommendation for the rate constant expression of the title reaction, based on the weighted average of the high-temperature data from selected studies, is given by k1 = 4.19 × 10(1)(T/K)(3.15) exp(5270 K/T) cm(3) mol(-1) s(-1) ±30%, which is valid over 1000-2500 K.

    View details for DOI 10.1021/acs.jpca.5b05725

    View details for PubMedID 26230910

  • Shock-Tube Measurement of Acetone Dissociation Using Cavity-Enhanced Absorption Spectroscopy of CO. journal of physical chemistry. A Wang, S., Sun, K., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2015; 119 (28): 7257-7262

    Abstract

    A direct measurement for the rate constant of the acetone dissociation reaction (CH3COCH3 = CH3CO + CH3) was conducted behind reflected shock wave, utilizing a sub-ppm sensitivity CO diagnostic achieved by cavity-enhanced absorption spectroscopy (CEAS). The current experiment eliminated the influence from secondary reactions and temperature change by investigating the clean pyrolysis of <20 ppm acetone in argon. For the first time, the acetone dissociation rate constant (k1) was directly measured over 5.5 orders of magnitude with a high degree of accuracy: k1 (1004-1494 K, 1.6 atm) = 4.39 × 10(55) T(-11.394) exp(-52 140K/T) ± 24% s(-1). This result was seen to agree with most previous studies and has bridged the gap between their temperature and pressure conditions. The current work also served as an example demonstration of the potential of using the CEAS technique in shock-tube kinetics studies.

    View details for DOI 10.1021/jp511642a

    View details for PubMedID 25659401

  • High-sensitivity interference-free diagnostic for measurement of methane in shock tubes JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Sur, R., Wang, S., Sun, K., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2015; 156: 80-87
  • Shock tube and modeling study of 2,7-dimethyloctane pyrolysis and oxidation COMBUSTION AND FLAME Li, S., Sarathy, S. M., Davidson, D. F., Hanson, R. K., Westbrook, C. K. 2015; 162 (5): 2296-2306
  • An experimental and modeling study of propene oxidation. Part 2: Ignition delay time and flame speed measurements COMBUSTION AND FLAME Burke, S. M., Burke, U., Mc Donagh, R., Mathieu, O., Osorio, I., Keesee, C., Morones, A., Petersen, E. L., Wang, W., DeVerter, T. A., Oehlschlaeger, M. A., Rhodes, B., Hanson, R. K., Davidson, D. F., Weber, B. W., Sung, C., Santner, J., Ju, Y., Haas, F. M., Dryer, F. L., Volkov, E. N., Nilsson, E. J., Konnov, A. A., Alrefae, M., Khaled, F., Farooq, A., Dirrenberger, P., Glaude, P., Battin-Leclerc, F., Curran, H. J. 2015; 162 (2): 296-314
  • Ignition delay times of conventional and alternative fuels behind reflected shock waves PROCEEDINGS OF THE COMBUSTION INSTITUTE Zhu, Y., Li, S., Davidson, D. F., Hanson, R. K. 2015; 35: 241-248
  • Constrained reaction volume shock tube study of n-heptane oxidation: Ignition delay times and time-histories of multiple species and temperature PROCEEDINGS OF THE COMBUSTION INSTITUTE Campbell, M. F., Wang, S., Goldenstein, C. S., Spearrin, R. M., Tulgestke, A. M., Zaczek, L. T., Davidson, D. F., Hanson, R. K. 2015; 35: 231-239
  • High-temperature iso-butene absorption diagnostic for shock tube kinetics using a pulsed quantum cascade laser near 11.3 mu m PROCEEDINGS OF THE COMBUSTION INSTITUTE Spearrin, R. M., Li, S., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2015; 35: 3645-3651
  • Shock Tube/Laser Absorption Measurements of Jet Fuel Pyrolysis and Oxidation 53rd AIAA Aerospace Sciences Meeting Zhu, Y., Hanson, R. K., Davidson, D. F. 2015

    View details for DOI 10.2514/6.2015-1158

  • A shock tube study of CH3OH + OH -> Products using OH laser absorption PROCEEDINGS OF THE COMBUSTION INSTITUTE Zaczek, L. T., Lam, K. Y., Davidson, D. F., Hanson, R. K. 2015; 35: 377-384
  • Shock Tube Study of Dimethylamine Oxidation INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Li, S., Davidson, D. F., Hanson, R. K. 2015; 47 (1): 19-26

    View details for DOI 10.1002/kin.20888

    View details for Web of Science ID 000345572600003

  • High temperature measurements for the rate constants of C-1-C-4 aldehydes with OH in a shock tube PROCEEDINGS OF THE COMBUSTION INSTITUTE Wang, S., Davidson, D. F., Hanson, R. K. 2015; 35: 473-480
  • Reaction Rate Constant of CH2O + H = HCO + H-2 Revisited: A Combined Study of Direct Shock Tube Measurement and Transition State Theory Calculation JOURNAL OF PHYSICAL CHEMISTRY A Wang, S., Dames, E. E., Davidson, D. F., Hanson, R. K. 2014; 118 (44): 10201-10209

    View details for DOI 10.1021/jp5085795

    View details for Web of Science ID 000344579100005

  • Reaction rate constant of CH2O + H = HCO + H2 revisited: a combined study of direct shock tube measurement and transition state theory calculation. The journal of physical chemistry. A Wang, S., Dames, E. E., Davidson, D. F., Hanson, R. K. 2014; 118 (44): 10201-9

    Abstract

    The rate constant of the H-abstraction reaction of formaldehyde (CH2O) by hydrogen atoms (H), CH2O + H = H2 + HCO, has been studied behind reflected shock waves with use of a sensitive mid-IR laser absorption diagnostic for CO, over temperatures of 1304-2006 K and at pressures near 1 atm. C2H5I was used as an H atom precursor and 1,3,5-trioxane as the CH2O precursor, to generate a well-controlled CH2O/H reacting system. By designing the experiments to maintain relatively constant H atom concentrations, the current study significantly boosted the measurement sensitivity of the target reaction and suppressed the influence of interfering reactions. The measured CH2O + H rate constant can be expressed in modified Arrhenius from as kCH2O+H(1304-2006 K, 1 atm) = 1.97 × 10(11)(T/K)(1.06) exp(-3818 K/T) cm(3) mol(-1)s(-1), with uncertainty limits estimated to be +18%/-26%. A transition-state-theory (TST) calculation, using the CCSD(T)-F12/VTZ-F12 level of theory, is in good agreement with the shock tube measurement and extended the temperature range of the current study to 200-3000 K, over which a modified Arrhenius fit of the rate constant can be expressed as kCH2O+H(200-3000 K) = 5.86 × 10(3)(T/K)(3.13) exp(-762 K/T) cm(3) mol(-1)s(-1).

    View details for DOI 10.1021/jp5085795

    View details for PubMedID 25319141

  • A comparative study of the chemical kinetics of methyl and ethyl propanoate FUEL Farooq, A., Davidson, D. F., Hanson, R. K., Westbrook, C. K. 2014; 134: 26-38
  • Shock tube study of ethylamine pyrolysis and oxidation COMBUSTION AND FLAME Li, S., Davidson, D. F., Hanson, R. K. 2014; 161 (10): 2512-2518
  • Recent advances in laser absorption and shock tube methods for studies of combustion chemistry PROGRESS IN ENERGY AND COMBUSTION SCIENCE Hanson, R. K., Davidson, D. F. 2014; 44: 103-114
  • Pyrolysis study of conventional and alternative fuels behind reflected shock waves FUEL Li, S., Zhu, Y., Davidson, D. F., Hanson, R. K. 2014; 132: 170-177
  • FTIR measurements of mid-IR absorption spectra of gaseous fatty acid methyl esters at T=25-500 degrees C JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Campbell, M. F., Freeman, K. G., Davidson, D. F., Hanson, R. K. 2014; 145: 57-73
  • Shock Tube Measurements of Ignition Delay Times for the Butanol Isomers Using the Constrained-Reaction-VolumeStrategy INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Bec, I. L., Zhu, Y., Davidson, D. F., Hanson, R. K. 2014; 46 (8): 433-442

    View details for DOI 10.1002/kin.20859

    View details for Web of Science ID 000338008900002

  • Ignition delay times of very-low-vapor-pressure biodiesel surrogates behind reflected shock waves FUEL Campbell, M. F., Davidson, D. F., Hanson, R. K. 2014; 126: 271-281
  • A second-generation constrained reaction volume shock tube. Review of scientific instruments Campbell, M. F., Tulgestke, A. M., Davidson, D. F., Hanson, R. K. 2014; 85 (5): 055108-?

    Abstract

    We have developed a shock tube that features a sliding gate valve in order to mechanically constrain the reactive test gas mixture to an area close to the shock tube endwall, separating it from a specially formulated non-reactive buffer gas mixture. This second-generation Constrained Reaction Volume (CRV) strategy enables near-constant-pressure shock tube test conditions for reactive experiments behind reflected shocks, thereby enabling improved modeling of the reactive flow field. Here we provide details of the design and operation of the new shock tube. In addition, we detail special buffer gas tailoring procedures, analyze the buffer/test gas interactions that occur on gate valve opening, and outline the size range of fuels that can be studied using the CRV technique in this facility. Finally, we present example low-temperature ignition delay time data to illustrate the CRV shock tube's performance.

    View details for DOI 10.1063/1.4875056

    View details for PubMedID 24880416

  • An improved kinetic mechanism for 3-pentanone pyrolysis and oxidation developed using multispecies time histories in shock-tubes COMBUSTION AND FLAME Dames, E. E., Lam, K., Davidson, D. F., Hanson, R. K. 2014; 161 (5): 1135-1145
  • Experimental and Modeling Study of the Thermal Decomposition of C3-C5 Ethyl Esters Behind Reflected Shock Waves JOURNAL OF PHYSICAL CHEMISTRY A Ren, W., Spearrin, R. M., Davidson, D. F., Hanson, R. K. 2014; 118 (10): 1785-1798

    Abstract

    The thermal decomposition of three ethyl esters, ethyl formate (C3H6O2), ethyl acetate (C4H8O2), and ethyl propanoate (C5H10O2), was studied behind reflected shock waves using laser absorption to measure concentration time-histories of H2O, CO2, and CO. Experimental conditions covered temperatures of 1301-1636 K, pressures of 1.48-1.72 atm, and reactant concentrations of 2000 ppm in argon. Recently developed mid-infrared laser diagnostics for H2O (2.5 μm), CO2 (4.3 μm), and CO (4.6 μm) provide orders-of-magnitude greater detectivity compared to previous near-infrared absorption sensors. The experimental results have highlighted significant differences among these three ethyl esters: negligible CO2 production during ethyl formate pyrolysis, quite slow CO formation rate during ethyl acetate pyrolysis, and nearly equal formation rate of H2O, CO2, and CO during ethyl propanoate pyrolysis. Detailed kinetic modeling was performed to understand the destruction pathways of these three ethyl esters with different alkyl chain lengths. Rate of production and sensitivity analyses were also carried out to interpret the experimental results and to identify the key reactions affecting experimental results.

    View details for DOI 10.1021/jp411766b

    View details for Web of Science ID 000333006100005

    View details for PubMedID 24450585

  • 1-Butanol ignition delay times at low temperatures: An application of the constrained-reaction-volume strategy COMBUSTION AND FLAME Zhu, Y., Davidson, D. F., Hanson, R. K. 2014; 161 (3): 634-643
  • Shock tube measurements of branched alkane ignition delay times FUEL Li, S., Campos, A., Davidson, D. F., Hanson, R. K. 2014; 118: 398-405
  • Pyrolysis and oxidation of decalin at elevated pressures: A shock-tube study COMBUSTION AND FLAME Zhu, Y., Davidson, D. F., Hanson, R. K. 2014; 161 (2): 371-383
  • High-Temperature Measurements of the Reactions of OH with Ethylamine and Dimethylamine JOURNAL OF PHYSICAL CHEMISTRY A Li, S., Dames, E., Davidson, D. F., Hanson, R. K. 2014; 118 (1): 70-77

    View details for DOI 10.1021/jp411141w

    View details for Web of Science ID 000329678100008

  • High-temperature measurements of the reactions of OH with ethylamine and dimethylamine. The journal of physical chemistry. A Li, S., Dames, E., Davidson, D. F., Hanson, R. K. 2014; 118 (1): 70-7

    Abstract

    The overall rate constants of hydroxyl radicals (OH) with ethylamine (EA: CH3CH2NH2) and dimethylamine (DMA: CH3NHCH3) were investigated behind reflected shock waves using UV laser absorption of OH radicals near 306.7 nm. tert-Butyl hydroperoxide (TBHP) was used as the fast source of OH at elevated temperatures. Test gas mixtures of individual amines and TBHP, diluted in argon, were shock-heated to temperatures from 901 to 1368 K at pressures near 1.2 atm. The overall rate constants were determined by fitting the measured OH time-histories with the computed profiles using a detailed mechanism developed by Lucassen et al. (Combust. Flame 2012, 159, 2254-2279). Over the temperature range studied, the measured rate constants can be expressed as kEA+OH = 1.10 × 10(7)·T(1.93) exp(1450/T) cm(3) mol(-1) s(-1), and kDMA+OH = 2.26 × 10(4)·T(2.69) exp(1797/T) cm(3) mol(-1) s(-1). Detailed error analyses were performed to estimate the overall uncertainties of the measured reaction rate constants, and the estimated (2σ) uncertainties were found to be ±31% at 901 K and ±22% at 1368 K for kEA+OH, and ±29% at 925 K and ±21% at 1307 K for kDMA+OH. Variational transition state theory was used to compute the H-abstraction rates by OH for ethylamine and dimethylamine, with the potential energy surface, geometries, frequencies, and electronic energies calculated by Galano and Alvarez-Idaboy (J. Chem. Theory Comput. 2008, 4, 322-327) at CCSD(T)/6-311++G(2d,2p) level of theory. The calculated reaction rate constants are in good agreement with the experimental data.

    View details for DOI 10.1021/jp411141w

    View details for PubMedID 24328257

  • Uncertainty-quantification analysis of the effects of residual impurities on hydrogen-oxygen ignition in shock tubes COMBUSTION AND FLAME Urzay, J., Kseib, N., Davidson, D. F., Iaccarino, G., Hanson, R. K. 2014; 161 (1): 1-15
  • Shock tube study of the pressure dependence of monomethylhydrazine pyrolysis COMBUSTION AND FLAME Li, S., Davidson, D. F., Hanson, R. K. 2014; 161 (1): 16-22
  • Shock tube study of methanol, methyl formate pyrolysis: CH3OH and CO time-history measurements COMBUSTION AND FLAME Ren, W., Dames, E., Hyland, D., Davidson, D. F., Hanson, R. K. 2013; 160 (12): 2669-2679
  • Shock tube measurements of the rate constant for the reaction cyclohexene -> ethylene+1,3-butadiene CHEMICAL PHYSICS LETTERS Stranic, I., Davidson, D. F., Hanson, R. K. 2013; 584: 18-23
  • High-temperature laser absorption diagnostics for CH2O and CH3CHO and their application to shock tube kinetic studies COMBUSTION AND FLAME Wang, S., Davidson, D. F., Hanson, R. K. 2013; 160 (10): 1930-1938
  • Constrained reaction volume approach for studying chemical kinetics behind reflected shock waves COMBUSTION AND FLAME Hanson, R. K., Pang, G. A., Chakraborty, S., Ren, W., Wang, S., Davidson, D. F. 2013; 160 (9): 1550-1558
  • Shock tube measurements and model development for morpholine pyrolysis and oxidation at high pressures COMBUSTION AND FLAME Li, S., Davidson, D. F., Hanson, R. K., Labbe, N. J., Westmoreland, P. R., Osswald, P., Kohse-Hoeinghaus, K. 2013; 160 (9): 1559-1571
  • A Shock Tube Study of H-2+OH -> H2O+H Using OH Laser Absorption INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Lam, K., Davidson, D. F., Hanson, R. K. 2013; 45 (6): 363-373

    View details for DOI 10.1002/kin.20771

    View details for Web of Science ID 000318176700003

  • Multi-species measurements in 2-butanol and i-butanol pyrolysis behind reflected shock waves COMBUSTION AND FLAME Stranic, I., Pyun, S. H., Davidson, D. F., Hanson, R. K. 2013; 160 (6): 1012-1019
  • Methane and ethylene time-history measurements in n-butane and n-heptane pyrolysis behind reflected shock waves FUEL Pyun, S. H., Ren, W., Davidson, D. F., Hanson, R. K. 2013; 108: 557-564
  • Shock tube measurements of methane, ethylene and carbon monoxide time-histories in DME pyrolysis COMBUSTION AND FLAME Pyun, S. H., Ren, W., Lam, K., Davidson, D. F., Hanson, R. K. 2013; 160 (4): 747-754
  • Multi-species time-history measurements during n-hexadecane oxidation behind reflected shock waves PROCEEDINGS OF THE COMBUSTION INSTITUTE Haylett, D. R., Davidson, D. F., Cook, R. D., Hong, Z., Ren, W., Pyun, S. H., Hanson, R. K. 2013; 34: 369-376
  • Formulation of an RP-1 pyrolysis surrogate from shock tube measurements of fuel and ethylene time histories FUEL MacDonald, M. E., Davidson, D. F., Hanson, R. K., Pitz, W. J., Mehl, M., Westbrook, C. K. 2013; 103: 1051-1059
  • Fuel and Ethylene Measurements during n-dodecane, methylcyclohexane, and iso-cetane pyrolysis in shock tubes FUEL MacDonald, M. E., Ren, W., Zhu, Y., Davidson, D. F., Hanson, R. K. 2013; 103: 1060-1068
  • Shock tube/laser absorption studies of the decomposition of methyl formate PROCEEDINGS OF THE COMBUSTION INSTITUTE Ren, W., Lam, K., Pyun, S. H., Farooq, A., Davidson, D. F., Hanson, R. K. 2013; 34: 453-461
  • Ignition delay times of methyl oleate and methyl linoleate behind reflected shock waves PROCEEDINGS OF THE COMBUSTION INSTITUTE Campbell, M. F., Davidson, D. F., Hanson, R. K., Westbrook, C. K. 2013; 34: 419-425
  • Multi-species time-history measurements during high-temperature acetone and 2-butanone pyrolysis PROCEEDINGS OF THE COMBUSTION INSTITUTE Lam, K., Ren, W., Pyun, S. H., Farooq, A., Davidson, D. F., Hanson, R. K. 2013; 34: 607-615
  • On the rate constants of OH + HO2 and HO2 + HO2: A comprehensive study of H2O2 thermal decomposition using multi-species laser absorption PROCEEDINGS OF THE COMBUSTION INSTITUTE Hong, Z., Lam, K., Sur, R., Wang, S., Davidson, D. F., Hanson, R. K. 2013; 34: 565-571
  • High-Temperature Measurements of the Reactions of OH with Small Methyl Esters: Methyl Formate, Methyl Acetate, Methyl Propanoate, and Methyl Butanoate JOURNAL OF PHYSICAL CHEMISTRY A Lam, K., Davidson, D. F., Hanson, R. K. 2012; 116 (50): 12229-12241

    Abstract

    The overall rate constants for the reactions of hydroxyl radicals (OH) with four small methyl esters, namely methyl formate (CH(3)OCHO), methyl acetate (CH(3)OC(O)CH(3)), methyl propanoate (CH(3)OC(O)C(2)H(5)), and methyl butanoate (CH(3)OC(O)C(3)H(7)), were investigated behind reflected shock waves using UV laser absorption of OH radicals near 306.69 nm. Test gas mixtures of individual methyl esters and tert-butyl hydroperoxide (TBHP), a fast source of OH at elevated temperatures, diluted in argon were shock-heated to temperatures spanning from 876 to 1371 K at pressures near 1.5 atm. The overall rate constants were determined by matching the measured OH time-histories with the computed profiles from the comprehensive chemical kinetic mechanisms of Dooley et al. (2010) and Dooley et al. (2008), which were originally developed for the oxidation of methyl formate and methyl butanoate, respectively. These measured values can be expressed in Arrhenius form as k(CH(3)OCHO+OH) = 2.56 × 10(13) exp(-2026/T) cm(3) mol(-1) s(-1), k(CH(3)OC(O)CH(3)+OH) = 3.59 × 10(13) exp(-2438/T) cm(3) mol(-1) s(-1), k(CH(3)OC(O)C(2)H(5)+OH) = 6.65 × 10(13) exp(-2539/T) cm(3) mol(-1) s(-1), and k(CH(3)OC(O)C(3)H(7)+OH) = 1.13 × 10(14) exp(-2515/T) cm(3) mol(-1) s(-1) over the temperature ranges studied. Detailed error analyses were performed to estimate the overall uncertainties of these reactions, and the estimated (2σ) uncertainties were found to be ±29% at 913 K and ±18% at 1289 K for k(CH(3)OCHO+OH), ± 29% at 930 K and ±17% at 1299 K for k(CH(3)OC(O)CH(3)+OH), ± 25% at 909 K and ±17% at 1341 K for k(CH(3)OC(O)C2H(5)+OH), and ±24% at 925 K and ±16% at 1320 K for k(CH(3)OC(O)C(3)H(7)+OH). We believe these are the first direct high-temperature rate constant measurements for the reactions of OH with these small methyl esters. These measured rate constants were also compared with the estimated values employed in different comprehensive kinetic mechanisms. Additionally, the structure-activity relationship from Kwok and Atkinson (1995) was used to estimate these four rate constants, and the estimations from this group-additivity model are in good agreement with the measurements (within ~25%) at the present experimental conditions.

    View details for DOI 10.1021/jp310256j

    View details for Web of Science ID 000312519800005

    View details for PubMedID 23194350

  • Shock tube studies of methyl butanoate pyrolysis with relevance to biodiesel COMBUSTION AND FLAME Farooq, A., Ren, W., Lam, K. Y., Davidson, D. F., Hanson, R. K., Westbrook, C. K. 2012; 159 (11): 3235-3241
  • Second-generation aerosol shock tube: an improved design SHOCK WAVES Haylett, D. R., Davidson, D. F., Hanson, R. K. 2012; 22 (6): 483-493
  • Multi-species measurements in 1-butanol pyrolysis behind reflected shock waves COMBUSTION AND FLAME Stranic, I., Pyun, S. H., Davidson, D. F., Hanson, R. K. 2012; 159 (11): 3242-3250
  • Shock tube measurements of 3-pentanone pyrolysis and oxidation COMBUSTION AND FLAME Lam, K., Ren, W., Hong, Z., Davidson, D. F., Hanson, R. K. 2012; 159 (11): 3251-3263
  • A shock tube study of the rate constants of HO2 and CH3 reactions COMBUSTION AND FLAME Hong, Z., Davidson, D. F., Lam, K., Hanson, R. K. 2012; 159 (10): 3007-3013
  • High-Temperature Measurements of the Reactions of OH with a Series of Ketones: Acetone, 2-Butanone, 3-Pentanone, and 2-Pentanone JOURNAL OF PHYSICAL CHEMISTRY A Lam, K., Davidson, D. F., Hanson, R. K. 2012; 116 (23): 5549-5559

    Abstract

    The overall rate constants for the reactions of hydroxyl radicals (OH) with a series of ketones, namely, acetone (CH(3)COCH(3)), 2-butanone (C(2)H(5)COCH(3)), 3-pentanone (C(2)H(5)COC(2)H(5)), and 2-pentanone (C(3)H(7)COCH(3)), were studied behind reflected shock waves over the temperature range of 870-1360 K at pressures of 1-2 atm. OH radicals were produced by rapid thermal decomposition of the OH precursor tert-butyl hydroperoxide (TBHP) and were monitored by the narrow line width ring dye laser absorption of the well-characterized R(1)(5) line in the OH A-X (0, 0) band near 306.69 nm. The overall rate constants were inferred by comparing the measured OH time histories with the simulated profiles from the detailed mechanisms of Pichon et al. (2009) and Serinyel et al. (2010). These measured values can be expressed in Arrhenius form as k(CH3COCH3+OH) = 3.30 × 10(13) exp(-2437/T) cm(3) mol(-1) s(-1), k(C2H5COCH3+OH )= 6.35 × 10(13) exp(-2270/T) cm(3) mol(-1) s(-1), k(C2H5COC2H5+OH) = 9.29 × 10(13) exp(-2361/T) cm(3) mol(-1) s(-1), and k(C3H7COCH3+OH) = 7.06 × 10(13) exp(-2020/T) cm(3) mol(-1) s(-1). The measured rate constant for the acetone + OH reaction from the current study is consistent with three previous experimental studies from Bott and Cohen (1991), Vasudevan et al. (2005), and Srinivasan et al. (2007), within ±20%. Here, we also present the first direct high-temperature rate constant measurements of 2-butanone + OH, 3-pentanone + OH, and 2-pentanone + OH reactions. The measured values for the 2-butanone + OH reaction are in close accord with the theoretical calculation from Zhou et al. (2011), and the measured values for the 3-pentanone + OH reaction are in excellent agreement with the estimates (by analogy with the H-atom abstraction rate constants from alkanes) from Serinyel et al. Finally, the structure-activity relationship from Kwok and Atkinson (1995) was used to estimate these four rate constants, and the estimated values from this group-additivity model show good agreement with the measurements (within ~25%) at the present experimental conditions.

    View details for DOI 10.1021/jp303853h

    View details for Web of Science ID 000305355900004

    View details for PubMedID 22607582

  • IR laser absorption diagnostic for C2H4 in shock tube kinetics studies INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Ren, W., Davidson, D. F., Hanson, R. K. 2012; 44 (6): 423-432

    View details for DOI 10.1002/kin.20599

    View details for Web of Science ID 000303042600007

  • CO concentration and temperature sensor for combustion gases using quantum-cascade laser absorption near 4.7 mu m APPLIED PHYSICS B-LASERS AND OPTICS Ren, W., Farooq, A., Davidson, D. F., Hanson, R. K. 2012; 107 (3): 849-860
  • Multispecies laser measurements of n-butanol pyrolysis behind reflected shock waves INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Cook, R. D., Davidson, D. F., Hanson, R. K. 2012; 44 (5): 303-311

    View details for DOI 10.1002/kin.20713

    View details for Web of Science ID 000302072400003

  • Shock tube measurements of ignition delay times for the butanol isomers COMBUSTION AND FLAME Stranic, I., Chase, D. P., Harmon, J. T., Yang, S., Davidson, D. F., Hanson, R. K. 2012; 159 (2): 516-527
  • Ignition delay times of low-vapor-pressure fuels measured using an aerosol shock tube COMBUSTION AND FLAME Haylett, D. R., Davidson, D. F., Hanson, R. K. 2012; 159 (2): 552-561
  • Broad-linewidth laser absorption measurements of oxygen between 211 and 235 nm at high temperatures JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Hong, Z., Lam, K., Davidson, D. F., Hanson, R. K. 2011; 112 (17): 2698-2703
  • Near-wall imaging using toluene-based planar laser-induced fluorescence in shock tube flow SHOCK WAVES Yoo, J., Mitchell, D., Davidson, D. F., Hanson, R. K. 2011; 21 (6): 523-532
  • Decomposition Measurements of RP-1, RP-2, JP-7, n-Dodecane, and Tetrahydroquinoline in Shock Tubes 44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit MacDonald, M. E., Davidson, D. F., Hanson, R. K. AMER INST AERONAUT ASTRONAUT. 2011: 981–89

    View details for DOI 10.2514/1.B34204

    View details for Web of Science ID 000295705700007

  • A comparative study of the oxidation characteristics of cyclohexane, methylcyclohexane, and n-butylcyclohexane at high temperatures COMBUSTION AND FLAME Hong, Z., Lam, K., Davidson, D. F., Hanson, R. K. 2011; 158 (8): 1456-1468
  • An improved H-2/O-2 mechanism based on recent shock tube/laser absorption measurements COMBUSTION AND FLAME Hong, Z., Davidson, D. F., Hanson, R. K. 2011; 158 (4): 633-644
  • Shock tube measurements of species time-histories in monomethyl hydrazine pyrolysis COMBUSTION AND FLAME Cook, R. D., Pyun, S. H., Cho, J., Davidson, D. F., Hanson, R. K. 2011; 158 (4): 790-795
  • Reactions of OH with butene isomers: measurements of the overall rates and a theoretical study. journal of physical chemistry. A Vasu, S. S., Huynh, L. K., Davidson, D. F., Hanson, R. K., Golden, D. M. 2011; 115 (12): 2549-2556

    Abstract

    Reactions of hydroxyl (OH) radicals with 1-butene (k(1)), trans-2-butene (k(2)), and cis-2-butene (k(3)) were studied behind reflected shock waves over the temperature range 880-1341 K and at pressures near 2.2 atm. OH radicals were produced by shock-heating tert-butyl hydroperoxide, (CH(3))(3)-CO-OH, and monitored by narrow-line width ring dye laser absorption of the well-characterized R(1)(5) line of the OH A-X (0, 0) band near 306.7 nm. OH time histories were modeled using a comprehensive C(5) oxidation mechanism, and rate constants for the reaction of OH with butene isomers were extracted by matching modeled and measured OH concentration time histories. We present the first high-temperature measurement of OH + cis-2-butene and extend the temperature range of the only previous high-temperature study for both 1-butene and trans-2-butene. With the potential energy surface calculated using CCSD(T)/6-311++G(d,p)//QCISD/6-31G(d), the rate constants and branching fractions for the H-abstraction channels of the reaction of OH with 1-butene were calculated in the temperature range 300-1500 K. Corrections for variational and tunneling effects as well as hindered-rotation treatments were included. The calculations are in good agreement with current and previous experimental data and with a recent theoretical study.

    View details for DOI 10.1021/jp112294h

    View details for PubMedID 21388160

  • Reactions of OH with Butene Isomers: Measurements of the Overall Rates and a Theoretical Study JOURNAL OF PHYSICAL CHEMISTRY A Vasu, S. S., Lam K Huynh, K. H., Davidson, D. F., Hanson, R. K., Golden, D. M. 2011; 115 (12): 2549-2556

    View details for DOI 10.1021/jp112294h

    View details for Web of Science ID 000288644600013

  • Shock Tube Study of Syngas Ignition in Rich CO2 Mixtures and Determination of the Rate of H + O-2 + CO2 -> HO2 + CO2 ENERGY & FUELS Vasu, S. S., Davidson, D. F., Hanson, R. K. 2011; 25 (3): 990-997

    View details for DOI 10.1021/ef1015928

    View details for Web of Science ID 000289613300016

  • Interference-free mid-IR laser absorption detection of methane MEASUREMENT SCIENCE & TECHNOLOGY Pyun, S. H., Cho, J., Davidson, D. F., Hanson, R. K. 2011; 22 (2)
  • Shock tube ignition delay time measurements in propane/O-2/argon mixtures at near-constant-volume conditions PROCEEDINGS OF THE COMBUSTION INSTITUTE Lam, K., Hong, Z., Davidson, D. F., Hanson, R. K. 2011; 33: 251-258
  • OH and C2H4 species time-histories during hexadecane and diesel ignition behind reflected shock waves PROCEEDINGS OF THE COMBUSTION INSTITUTE Haylett, D. R., Cook, R. D., Davidson, D. F., Hanson, R. K. 2011; 33: 167-173
  • Multi-species time-history measurements during n-dodecane oxidation behind reflected shock waves PROCEEDINGS OF THE COMBUSTION INSTITUTE Davidson, D. F., Hong, Z., Pilla, G. L., Farooq, A., Cook, R. D., Hanson, R. K. 2011; 33: 151-157
  • A new shock tube study of the H + O-2 -> OH plus O reaction rate using tunable diode laser absorption of H2O near 2.5 mu m PROCEEDINGS OF THE COMBUSTION INSTITUTE Hong, Z., Davidson, D. F., Barbour, E. A., Hanson, R. K. 2011; 33: 309-316
  • Shock tube/laser absorption measurements of ethylene time-histories during ethylene and n-heptane pyrolysis PROCEEDINGS OF THE COMBUSTION INSTITUTE Pilla, G. L., Davidson, D. F., Hanson, R. K. 2011; 33: 333-340
  • Shock Tube/Laser Absorption Measurements of the Reaction Rates of OH with Ethylene and Propene JOURNAL OF PHYSICAL CHEMISTRY A Vasu, S. S., Hong, Z., Davidson, D. F., Hanson, R. K., Golden, D. M. 2010; 114 (43): 11529-11537

    Abstract

    Reaction rates of hydroxyl (OH) radicals with ethylene (C₂H₄) and propene (C₃H₆) were studied behind reflected shock waves. OH + ethylene → products (rxn 1) rate measurements were conducted in the temperature range 973-1438 K, for pressures from 2 to 10 atm, and for initial concentrations of ethylene of 500, 751, and 1000 ppm. OH + propene → products (rxn 2) rate measurements spanned temperatures of 890-1366 K, pressures near 2.3 atm, and initial propene concentrations near 300 ppm. OH radicals were produced by shock-heating tert-butyl hydroperoxide, (CH₃)₃-CO-OH, and monitored by laser absorption near 306.7 nm. Rate constants for the reactions of OH with ethylene and propene were extracted by matching modeled and measured OH concentration time-histories in the reflected shock region. Current data are in excellent agreement with previous studies and extend the temperature range of OH + propene data. Transition state theory calculations using recent ab initio results give excellent agreement with our measurements and other data outside our temperature range. Fits (in units of cm³/mol/s) to the abstraction channels of OH + ethylene and OH + propene are k₁ = 2.23 × 10⁴ (T)(2.745) exp(-1115 K/T) for 600-2000 K and k₂ = 1.94 × 10⁶ (T)(2.229) exp(-540 K/T) for 700-1500 K, respectively. A rate constant determination for the reaction TBHP → products (rxn 3) was also obtained in the range 745-1014 K using OH data from behind both incident and reflected shock waves. These high-temperature measurements were fit with previous low-temperature data, and the following rate expression (0.6-2.6 atm), applicable over the temperature range 400-1050 K, was obtained: k₃ (1/s) = 8.13 × 10⁻¹² (T)(7.83) exp(-14598 K/T).

    View details for DOI 10.1021/jp106049s

    View details for Web of Science ID 000283471900020

    View details for PubMedID 20923208

  • Planar laser-induced fluorescence imaging in shock tube flows EXPERIMENTS IN FLUIDS Yoo, J., Mitchell, D., Davidson, D. F., Hanson, R. K. 2010; 49 (4): 751-759
  • Multi-species time-history measurements during n-heptane oxidation behind reflected shock waves COMBUSTION AND FLAME Davidson, D. F., Hong, Z., Pilla, G. L., Farooq, A., Cook, R. D., Hanson, R. K. 2010; 157 (10): 1899-1905
  • Measurements of the reaction of OH with n-butanol at high-temperatures CHEMICAL PHYSICS LETTERS Vasu, S. S., Davidson, D. F., Hanson, R. K., Golden, D. M. 2010; 497 (1-3): 26-29
  • High-Temperature Measurements and a Theoretical Study of the Reaction of OH with 1,3-Butadiene JOURNAL OF PHYSICAL CHEMISTRY A Vasu, S. S., Zador, J., Davidson, D. F., Hanson, R. K., Golden, D. M., Miller, J. A. 2010; 114 (32): 8312-8318

    Abstract

    The reaction of hydroxyl (OH) radicals with 1,3-butadiene (C(4)H(6)) was studied behind reflected shock waves over the temperature range 1011-1406 K and at pressures near 2.2 atm. OH radicals were produced by shock-heating tert-butyl hydroperoxide, (CH(3))(3)-CO-OH, and were monitored by narrow line width ring dye laser absorption of the well-characterized R(1)(5) line of the OH A-X (0,0) band near 306.7 nm. OH time histories were modeled using a comprehensive 1,3-butadiene oxidation mechanism, and rate constants for the reaction of OH with 1,3-butadiene were extracted by matching modeled and measured OH concentration time histories. Detailed error analyses yielded an uncertainty estimate of +/-13% at 1200 K for the rate coefficient of the target reaction. The current data extends the temperature range of the only previous high-temperature study for this reaction. The rate coefficient and the branching fractions for the H-abstraction channels of the target reaction were also calculated over the temperature range 250-2500 K using variational transition-state theory based on QCISD(T)/cc-pVinfinityZ//B3LYP/6-311++G(d,p) quantum chemistry. The calculations are in good agreement with the experimental results above 1200 K.

    View details for DOI 10.1021/jp104880u

    View details for Web of Science ID 000280727200013

    View details for PubMedID 20701338

  • Shock-Tube Experiments and Kinetic Modeling of Toluene Ignition JOURNAL OF PROPULSION AND POWER Vasu, S. S., Davidson, D. F., Hanson, R. K. 2010; 26 (4): 776-783

    View details for DOI 10.2514/1.46637

    View details for Web of Science ID 000280255300017

  • A Shock Tube Study of OH + H2O2 -> H2O + HO2 and H2O2 + M -> 2OH+M using Laser Absorption of H2O and OH JOURNAL OF PHYSICAL CHEMISTRY A Hong, Z., Cook, R. D., Davidson, D. F., Hanson, R. K. 2010; 114 (18): 5718-5727

    Abstract

    The rate constants of the reactions: (1) H2O2+M-->2OH+M, (2) OH+H2O2-->H2O+HO2 were measured in shock-heated H(2)O(2)/Ar mixtures using laser absorption diagnostics for H(2)O and OH. Time-histories of H(2)O were monitored using tunable diode laser absorption at 2550.96 nm, and time-histories of OH were achieved using ring dye laser absorption at 306 nm. Initial H(2)O(2) concentrations were also determined utilizing the H(2)O diagnostic. On the basis of simultaneous time-history measurements of OH and H(2)O, k(2) was found to be 4.6 x 10(13) exp(-2630 K/T) [cm(3) mol(-1) s(-1)] over the temperature range 1020-1460 K at 1.8 atm; additional measurements of k(2) near 1 atm showed no significant pressure dependence. Similarly, k(1) was found to be 9.5 x 10(15) exp(-21 250 K/T) [cm(3) mol(-1) s(-1)] over the same temperature and pressure range.

    View details for DOI 10.1021/jp100204z

    View details for Web of Science ID 000277280400013

    View details for PubMedID 20397668

  • Experimental Study of the Rate of OH + HO2 -> H2O + O-2 at High Temperatures Using the Reverse Reaction JOURNAL OF PHYSICAL CHEMISTRY A Hong, Z., Vasu, S. S., Davidson, D. F., Hanson, R. K. 2010; 114 (17): 5520-5525

    Abstract

    The rate constant of the reaction OH + HO(2) --> H(2)O + O(2) (1) can be inferred at high temperatures from measurements of the rate of its reverse reaction H(2)O + O(2) --> OH + HO(2) (-1). In this work, we used laser absorption of both H(2)O and OH to study the reverse reaction in shock-heated H(2)O/O(2)/Ar mixtures over the temperature range 1600-2200 K. Initial H(2)O concentrations were determined using tunable diode laser absorption near 2.5 microm, and OH concentration time-histories were measured using UV ring dye laser absorption near 306.7 nm. Detailed kinetic analysis of the OH time-history profiles yielded a value for the rate constant k(1) of (3.3 +/- 0.9) x 10(13) [cm(3) mol(-1) s(-1)] between 1600 and 2200 K. The results of this study agree well with those reported by Srinivasan et al. (Srinivasan, N.K.; Su, M.-C.; Sutherland, J.W.; Michael, J.V.; Ruscic, B. J. Phys. Chem. A 2006, 110, 6602-6607) in the temperature regime between 1200 and 1700 K. The combination of the two studies suggests only a weak temperature dependence of k(1) above 1200 K. Data from the current study and that of Keyser (Keyser, L.F. J. Phys. Chem. 1988, 92, 1193-1200) at lower temperatures can be described by the k(1) expression proposed by Baulch et al. (Baulch, D.L.; Cobos, C.J.; Cox, R.A.; Esser, C.; Frank, P.; Just, Th.; Kerr, J.A.; Pilling, M.J.; Troe, J.; Walker, R.W.; Warnatz, J. J. Phys. Chem. Ref. Data 1992, 21, 411), k(1) = 2.89 x 10(13) exp(252/T) [cm(3) mol(-1) s(-1)]. However, it should be noted that some previous studies suggest a k(1) minimum around 1250 K (Hippler, H.; Neunaber, H.; Troe, J. J. Chem. Phys. 1995, 103, 3510-3516) or 1000 K (Kappel, C.; Luther, K.; Troe, J. Phys. Chem. Chem. Phys. 2002, 4, 4392-4398).

    View details for DOI 10.1021/jp100739t

    View details for Web of Science ID 000277053400012

    View details for PubMedID 20392098

  • Ignition Delay Time Measurements of Normal Alkanes and Simple Oxygenates JOURNAL OF PROPULSION AND POWER Davidson, D. F., Ranganath, S. C., Lam, K., Liaw, M., Hong, Z., Hanson, R. K. 2010; 26 (2): 280-287

    View details for DOI 10.2514/1.44034

    View details for Web of Science ID 000276712400009

  • Hydrogen Peroxide Decomposition Rate: A Shock Tube Study Using Tunable Laser Absorption of H2O near 2.5 mu m JOURNAL OF PHYSICAL CHEMISTRY A Hong, Z., Farooq, A., Barbour, E. A., Davidson, D. F., Hanson, R. K. 2009; 113 (46): 12919-12925

    Abstract

    The thermal decomposition of hydrogen peroxide was measured behind reflected shock waves in hydrogen peroxide/inert gas mixtures using a sensitive laser diagnostic for water vapor. In these mixtures, the formation rate of water is predominantly controlled by the decomposition rate of hydrogen peroxide. Rate determinations were made over a temperature range of 1000-1200 K and a pressure range of 0.9-3.2 atm for both argon and nitrogen carrier gases. Good detection sensitivity for water was achieved using tunable diode laser absorption of water at 2550.96 nm within its v(3) fundamental band. Hydrogen peroxide decomposition rates were found to be independent of pressure at 0.9 and 1.7 atm and showed only slight influence of pressure at 3.2 atm. The best fit of the current data to the low-pressure-limit rate for H(2)O(2) dissociation in argon bath gas is k(1,0) = 10(15.97+/-0.10) exp(-21 220 +/- 250 K/T) [cm(3) mol(-1) s(-1)] (1000-1200 K). Experiments conducted in a nitrogen bath gas show a relative collision efficiency of argon to nitrogen of 0.67.

    View details for DOI 10.1021/jp907219f

    View details for Web of Science ID 000271583100021

    View details for PubMedID 19799388

  • The effect of oxygenates on soot formation in rich heptane mixtures: A shock tube study FUEL Hong, Z., Davidson, D. F., VASU, S. S., Hanson, R. K. 2009; 88 (10): 1901-1906
  • High-Temperature Shock Tube Measurements of Dimethyl Ether Decomposition and the Reaction of Dimethyl Ether with OH JOURNAL OF PHYSICAL CHEMISTRY A Cook, R. D., Davidson, D. F., Hanson, R. K. 2009; 113 (37): 9974-9980

    Abstract

    We measured the first high-temperature rate measurements of two dimethyl ether (DME) reactions, (1) DME + Ar --> CH3O + CH3 + Ar and (2) DME + OH --> CH3OCH2 + H2O, in a shock tube by monitoring OH radicals. OH was measured with a narrow-line width laser absorption diagnostic using the well-known R1(5) line of the A-X(0,0) transition at 306.7 nm. The rate k1 is in the falloff regime at high temperatures, so it was measured at several pressures from 0.6 to 11.5 atm and temperatures from 1349 to 1790 K. OH radicals were formed by shock-heating mixtures of DME and O2 in Ar. These mixtures take advantage of the rapid decomposition of the product CH3O, forming H-atoms, which react with O2 to form OH. In carefully chosen mixtures, OH concentration is primarily sensitive to k1 and the well-known rate of H + O2 --> OH + O. Uncertainty in the k1 measurements was estimated to be +/-35%. The rate measurements were then modeled using RRKM theory, which describes the data quite well. Both the rate measurements and the RRKM model were fit from 1000 to 1800 K using the Troe falloff form: k(1,infinity)(T) = (4.38 x 10(21))T(-1.57) exp(-42,220 K/T) s(-1), k(1,o) = 7.52 x 10(15) exp(-21,537 K/T) cm3 mol(-1) s(-1), and F(cent) = 0.454 exp(-T/2510). The rate of k2 was measured at pressures near 1.6 atm and temperatures from 923 to 1423 K. OH radicals were generated by the thermal decomposition of the OH precursor tert-butyl hydroperoxide (TBHP), and k2 was inferred from the observed decay of OH with an estimated uncertainty of +/-40%. The high-temperature measurements were compared with several rate evaluations and previous low-temperature measurements. The rate evaluation by Curran et al. of k2 = (6.32 x 10(6))T2 exp(328 K/T) (cm3 mol(-1) s(-1)) was found to be an excellent fit to both the previous low-temperature measurements and this work.

    View details for DOI 10.1021/jp902403n

    View details for Web of Science ID 000269656000005

    View details for PubMedID 19694474

  • Recent advances in shock tube/laser diagnostic methods for improved chemical kinetics measurements SHOCK WAVES Davidson, D. F., Hanson, R. K. 2009; 19 (4): 271-283
  • Contact surface tailoring condition for shock tubes with different driver and driven section diameters SHOCK WAVES Hong, Z., Davidson, D. F., Hanson, R. K. 2009; 19 (4): 331-336
  • The use of driver inserts to reduce non-ideal pressure variations behind reflected shock waves SHOCK WAVES Hong, Z., Pang, G. A., Vasu, S. S., Davidson, D. F., Hanson, R. K. 2009; 19 (2): 113-123
  • OH time-histories during oxidation of n-heptane and methylcyclohexane at high pressures and temperatures COMBUSTION AND FLAME Vasu, S. S., Davidson, D. F., Hanson, R. K. 2009; 156 (4): 736-749
  • Jet fuel ignition delay times: Shock tube experiments over wide conditions and surrogate model predictions (vol 152, pg 125, 2008) COMBUSTION AND FLAME Vasu, S. S., Davidson, D. F., Hanson, R. K. 2009; 156 (4): 946-946
  • Shock Tube Study of Methylcyclohexane Ignition over a Wide Range of Pressure and Temperature ENERGY & FUELS Vasu, S. S., Davidson, D. F., Hong, Z., Hanson, R. K. 2009; 23 (1): 175-185

    View details for DOI 10.1021/ef800694g

    View details for Web of Science ID 000263629900026

  • Measurements of ignition delay times and OH species concentrations in DME/O-2/Ar mixtures 26th International Symposium on Shock Waves Cook, R. D., Davidson, D. F., Hanson, R. K. SPRINGER-VERLAG BERLIN. 2009: 763–767
  • An experimental and computational study of methyl ester decomposition pathways using shock tubes PROCEEDINGS OF THE COMBUSTION INSTITUTE Farooq, A., Davidson, D. F., Hanson, R. K., Huynh, L. K., Violi, A. 2009; 32: 247-253
  • Shock tube measurements of ignition delay times and OH time-histories in dimethyl ether oxidation PROCEEDINGS OF THE COMBUSTION INSTITUTE Cook, R. D., Davidson, D. F., Hanson, R. K. 2009; 32: 189-196
  • A diode laser absorption sensor for rapid measurements of temperature and water vapor in a shock tube 26th International Symposium on Shock Waves Li, H., Farooq, A., Cook, R. D., Davidson, D. F., Jeffries, J. B., Hanson, R. K. SPRINGER-VERLAG BERLIN. 2009: 409–414
  • High-pressure shock tube experiments and modeling of n-dodecane/air ignition 26th International Symposium on Shock Waves VASU, S. S., Davidson, D. F., Hanson, R. K. SPRINGER-VERLAG BERLIN. 2009: 293–298
  • Application of an aerosol shock tube to the measurement of diesel ignition delay times PROCEEDINGS OF THE COMBUSTION INSTITUTE Haylett, D. R., Lappas, P. P., Davidson, D. F., Hanson, R. K. 2009; 32: 477-484
  • n-Dodecane oxidation at high-pressures: Measurements of ignition delay times and OH concentration time-histories PROCEEDINGS OF THE COMBUSTION INSTITUTE Vasu, S. S., Davidson, D. F., Hong, Z., Vasudevan, V., Hanson, R. K. 2009; 32: 173-180
  • Experimental study and modeling of shock tube ignition delay times for hydrogen-oxygen-argon mixtures at low temperatures PROCEEDINGS OF THE COMBUSTION INSTITUTE Pang, G. A., Davidson, D. F., Hanson, R. K. 2009; 32: 181-188
  • Two-wavelength mid-IR diagnostic for temperature and n-dodecane concentration in an aerosol shock tube APPLIED PHYSICS B-LASERS AND OPTICS Klingbeil, A. E., Jeffries, J. B., Davidson, D. F., Hanson, R. K. 2008; 93 (2-3): 627-638
  • Development of an aerosol shock tube for kinetic studies of low-vapor-pressure fuels COMBUSTION AND FLAME Davidson, D. F., Haylett, D. R., Hanson, R. K. 2008; 155 (1-2): 108-117
  • A simple reactive gasdynamic model for the computation of gas temperature and species concentrations behind reflected shock waves INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Li, H., Owens, Z. C., Davidson, D. F., Hanson, R. K. 2008; 40 (4): 189-198

    View details for DOI 10.1002/kin.20305

    View details for Web of Science ID 000254068600003

  • Jet fuel ignition delay times: Shock tube experiments over wide conditions and surrogate model predictions COMBUSTION AND FLAME Vasu, S. S., Davidson, D. E., Hanson, R. K. 2008; 152 (1-2): 125-143
  • Shock tube study of the reaction of CH with N-2: Overall rate and branching ratio JOURNAL OF PHYSICAL CHEMISTRY A Vasudevan, V., Hanson, R. K., Bowman, C. T., Golden, D. M., Davidson, D. F. 2007; 111 (46): 11818-11830

    Abstract

    We have studied the reaction between CH and N2, (1) CH + N2 --> products, in shock tube experiments using CH and NCN laser absorption. CH was monitored by continuous-wave, narrow-line-width laser absorption at 431.1 nm. The overall rate coefficient of the CH + N2 reaction was measured between 1943 and 3543 K, in the 0.9-1.4 atm pressure range, using a CH perturbation approach. CH profiles recorded upon shock-heating dilute mixtures of ethane in argon and acetic anhydride in argon were perturbed by the addition of nitrogen. The perturbation in the CH concentration was principally due to the reaction between CH and N2. Rate coefficients for the overall reaction were inferred by kinetically modeling the perturbed CH profiles. A least-squares, two-parameter fit of the current overall rate coefficient measurements was k1 = 6.03 x 1012 exp(-11150/T [K]) (cm3 mol-1 s-1). The uncertainty in k1 was estimated to be approximately +/-25% and approximately +/-35% at approximately 3350 and approximately 2100 K, respectively. At high temperatures, there are two possible product channels for the reaction between CH and N2, (1a) CH + N2 --> HCN + N and (1b) CH + N2 --> H + NCN. The large difference in the rates of the reverse reactions enabled inference of the branching ratio of reaction 1, k1b/(k1b + k1a), in the 2228-2905 K temperature range by CH laser absorption in experiments in a nitrogen bath. The current CH measurements are consistent with a branching ratio of 1 and establish NCN and H as the primary products of the CH + N2 reaction. A detailed and systematic uncertainty analysis, taking into account experimental and mechanism-induced contributions, yields a conservative lower bound of 0.70 for the branching ratio. NCN was also detected by continuous-wave, narrow-line-width laser absorption at 329.13 nm. The measured NCN time histories were used to infer the rate coefficient of the reaction between H and NCN, H + NCN --> HCN + N, and to estimate an absorption coefficient for the NCN radical.

    View details for DOI 10.1021/jp075638c

    View details for Web of Science ID 000250967800012

    View details for PubMedID 17958405

  • High-temperature shock tube measurements of methyl radical decomposition JOURNAL OF PHYSICAL CHEMISTRY A Vasudevan, V., Hanson, R. K., Golden, D. M., Bowman, C. T., Davidson, D. F. 2007; 111 (19): 4062-4072

    Abstract

    We have studied the two-channel thermal decomposition of methyl radicals in argon, involving the reactions CH3 + Ar --> CH + H2 + Ar (1a) and CH3 + Ar --> CH2 + H + Ar (1b), in shock tube experiments over the 2253-3527 K temperature range, at pressures between 0.7 and 4.2 atm. CH was monitored by continuous-wave, narrow-line-width laser absorption at 431.1311 nm. The collision-broadening coefficient for CH in argon, 2gamma(CH-Ar), was measured via repeated single-frequency experiments in the ethane pyrolysis system behind reflected shock waves. The measured 2gamma(CH-Ar) value and updated spectroscopic and molecular parameters were used to calculate the CH absorption coefficient at 431.1311 nm (23194.80 cm(-1)), which was then used to convert raw traces of fractional transmission to quantitative CH concentration time histories in the methyl decomposition experiments. The rate coefficient of reaction 1a was measured by monitoring CH radicals generated upon shock-heating highly dilute mixtures of ethane, C2H6, or methyl iodide, CH3I, in an argon bath. A detailed chemical kinetic mechanism was used to model the measured CH time histories. Within experimental uncertainty and scatter, no pressure dependence could be discerned in the rate coefficient of reaction 1a in the 0.7-4.2 atm pressure range. A least-squares, two-parameter fit of the current measurements, applicable between 2706 and 3527 K, gives k(1a) (cm(3) mol(-1) s(-1)) = 3.09 x 1015 exp[-40700/T (K)]. The rate coefficient of reaction 1b was determined by shock-heating dilute mixtures of C2H6 or CH3I and excess O2 in argon. During the course of reaction, OH radicals were monitored using the well-characterized R(1)(5) line of the OH A-X (0,0) band at 306.6871 nm (32606.52 cm(-1)). H atoms generated via reaction 1b rapidly react with O2, which is present in excess, forming OH. The OH traces are primarily sensitive to reaction 1b, reaction 9 (H + O2 --> OH + O) and reaction 10 (CH3 + O2 --> products), where the rate coefficients of reactions 9 and 10 are relatively well-established. No pressure dependence could be discerned for reaction 1b between 1.1 and 3.9 atm. A two-parameter, least-squares fit of the current data, valid over the 2253-2975 K temperature range, yields the rate expression k(1b) (cm(3) mol(-1) s(-1)) = 2.24 x 10(15) exp[-41600/T (K)]. Theoretical calculations carried out using a master equation/RRKM analysis fit the measurements reasonably well.

    View details for DOI 10.1021/jp0677187

    View details for Web of Science ID 000246341200040

    View details for PubMedID 17388279

  • Shock-induced behavior in micron-sized water aerosols PHYSICS OF FLUIDS Hanson, T. C., Davidson, D. F., Hanson, R. K. 2007; 19 (5)

    View details for DOI 10.1063/1.2736082

    View details for Web of Science ID 000246892700035

  • Thermal decomposition of toluene: Overall rate and branching ratio PROCEEDINGS OF THE COMBUSTION INSTITUTE Oehlschlaeger, M. A., Davidson, D. F., Hanson, R. K. 2007; 31: 211-219
  • Methyl concentration time-histories during iso-octane and n-heptane oxidation and pyrolysis PROCEEDINGS OF THE COMBUSTION INSTITUTE Davidson, D. F., Oehlschlaeger, M. A., Hanson, R. K. 2007; 31: 321-328
  • High-temperature measurements of the rates of the reactions CH2O+Ar -> Products and CH2O+O-2 -> Products PROCEEDINGS OF THE COMBUSTION INSTITUTE Vasudevan, V., Davidson, D. F., Hanson, R. K., Bowman, C. T., Golden, D. M. 2007; 31: 175-183
  • Investigation of the reaction of toluene with molecular oxygen in shock-heated gases COMBUSTION AND FLAME Oehlschlaeger, M. A., Davidson, D. F., Hanson, R. K. 2006; 147 (3): 195-208
  • Experimental investigation of toluene plus H -> benzyl plus H-2 at high temperatures JOURNAL OF PHYSICAL CHEMISTRY A Oehlschlaeger, M. A., Davidson, D. F., Hanson, R. K. 2006; 110 (32): 9867-9873

    Abstract

    The reaction of toluene with hydrogen atoms yielding benzyl and molecular hydrogen, C(6)H(5)CH(3) + H --> C(6)H(5)CH(2) + H(2), was investigated using UV laser absorption of benzyl radicals at 266 nm in shock tube experiments. Test gas mixtures of toluene and ethyl iodide, an H-atom source, diluted in argon were heated in reflected shock waves to temperatures ranging from 1256 to 1667 K at total pressures around 1.7 bar. Measurement of laser absorption at 266 nm due to benzyl radicals allowed determination of the rate coefficient of the title reaction, reaction 1. A two-parameter best-fit Arrhenius expression for the rate determinations over the temperature range of these experiments is given by k(1)(T) = 1.33 x 10(15) exp(-14880 [cal/mol]/RT) [cm(3) mol(-1) s(-1)]. With the use of both the high-temperature shock tube measurements reported here and the rate coefficient determination of Ellis et al. (Ellis, C.; Scott, M. S.; Walker, R. W. Combust. Flame 2003, 132, 291) at 773 K the best-fit rate coefficient for reaction 1 can be described using a three-parameter Arrhenius expression by k(1)(T) = 6.47T (3.98) exp(-3384 [cal/mol]/RT) [cm(3) mol(-1) s(-1)].

    View details for DOI 10.1021/jp062567t

    View details for Web of Science ID 000239655800012

    View details for PubMedID 16898688

  • High-temperature thermal decomposition of benzyl radicals JOURNAL OF PHYSICAL CHEMISTRY A Oehlschlaeger, M. A., Davidson, D. F., Hanson, R. K. 2006; 110 (21): 6649-6653

    Abstract

    The thermal decomposition of the benzyl radical was studied in shock tube experiments using ultraviolet laser absorption at 266 nm for detection of benzyl. Test gas mixtures of 50 and 100 ppm of benzyl iodide dilute in argon were heated in reflected shock waves to temperatures ranging from 1430 to 1730 K at total pressures around 1.5 bar. The temporal behavior of the 266 nm absorption allowed for determination of the benzyl absorption cross-section at 266 nm and the rate coefficient for benzyl decomposition, C6H5CH2 --> C7H6 + H. The rate coefficient for benzyl decomposition at 1.5 bar can be described using a two-parameter Arrhenius expression by k1(T) = 8.20 x 10(14) exp(-40 600 K/T) [s(-1)], and the benzyl absorption cross-section at 266 nm was determined to be sigma(benzyl) = 1.9 x 10(-17) cm2 molecule(-1) with no discernible temperature dependence over the temperature range of the experiments.

    View details for DOI 10.1021/jp0553961

    View details for Web of Science ID 000237831500011

    View details for PubMedID 16722678

  • Temperature measurement using ultraviolet laser absorption of carbon dioxide behind shock waves APPLIED OPTICS Oehlschlaeger, M. A., Davidson, D. F., Jeffries, J. B. 2005; 44 (31): 6599-6605

    Abstract

    A diagnostic for microsecond time-resolved temperature measurements behind shock waves, using ultraviolet laser absorption of vibrationally hot carbon dioxide, is demonstrated. Continuous-wave laser radiation at 244 and 266 nm was employed to probe the spectrally smooth CO2 ultraviolet absorption, and an absorbance ratio technique was used to determine temperature. Measurements behind shock waves in both nonreacting and reacting (ignition) systems were made, and comparisons with isentropic and constant-volume calculations are reported.

    View details for Web of Science ID 000232938000009

    View details for PubMedID 16270548

  • High-temperature UV absorption of methyl radicals behind shock waves JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Oehlschlaeger, M. A., Davidson, D. F., Hanson, R. K. 2005; 92 (4): 393-402
  • High-temperature measurements of the reactions of OH with toluene and acetone JOURNAL OF PHYSICAL CHEMISTRY A Vasudevan, V., Davidson, D. F., Hanson, R. K. 2005; 109 (15): 3352-3359

    Abstract

    The reaction of hydroxyl [OH] radicals with toluene [C6H5CH3] was studied at temperatures between 911 and 1389 K behind reflected shock waves at pressures of approximately 2.25 atm. OH radicals were generated by rapid thermal decomposition of shock-heated tert-butyl hydroperoxide [(CH3)3-CO-OH], and monitored by narrow-line width ring dye laser absorption of the well-characterized R1(5) line of the OH A-X (0,0) band near 306.7 nm. OH time histories were modeled by using a comprehensive toluene oxidation mechanism. Rate constants for the reaction of C6H5CH3 with OH were extracted by matching modeled and measured OH concentration time histories in the reflected shock region. Detailed error analyses yielded an uncertainty estimate of +/-30% at 1115 K for the rate coefficient of this reaction. The current high-temperature data were fit with the lower temperature measurements of Tully et al. [J. Phys. Chem. 1981, 85, 2262-2269] to the following two-parameter form, applicable over 570-1389 K: k3 = (1.62 x 10(13)) exp(-1394/T [K]) [cm3 mol(-1) s(-1)]. The reaction between OH radicals and acetone [CH3COCH3] was one of the secondary reactions encountered in the toluene + OH experiments. Direct high-temperature measurements of this reaction were carried out at temperatures ranging from 982 to 1300 K in reflected shock wave experiments at an average total pressure of 1.65 atm. Uncertainty limits were estimated to be +/-25% at 1159 K. A two-parameter fit of the current data yields the following rate expression: k6 = (2.95 x 10(13)) exp(-2297/T [K]) [cm3 mol(-1) s(-1)].

    View details for DOI 10.1021/jp0501143

    View details for Web of Science ID 000228407700012

    View details for PubMedID 16833670

  • Direct measurements of the reaction OH+CH2O -> HCO+H(2)Oat high temperatures INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Vasudevan, V., Davidson, D. F., Hanson, R. K. 2005; 37 (2): 98-109

    View details for DOI 10.1002/kin.20056

    View details for Web of Science ID 000226341900006

  • Carbon dioxide thermal decomposition: Observation of incubation ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS Oehlschlaeger, M. A., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2005; 219 (5): 555-567
  • UV absorption of CO2 for temperature diagnostics of hydrocarbon combustion applications 30th International Symposium on Combustion Jeffries, J. B., Schulz, C., Mattison, D. W., Oehlschlaeger, M. A., Bessler, W. G., Lee, T., Davidson, D. F., Hanson, R. K. ELSEVIER SCIENCE INC. 2005: 1591–1599
  • Shock tube ignition measurements of iso-octane/air and toluene/air at high pressures 30th International Symposium on Combustion Davidson, D. F., Gauthier, B. M., Hanson, R. K. ELSEVIER SCIENCE INC. 2005: 1175–1182
  • Shock tube measurements of toluene ignition times and OH concentration time histories 30th International Symposium on Combustion Vasudevan, V., Davidson, D. F., Hanson, R. K. ELSEVIER SCIENCE INC. 2005: 1155–1163
  • High-temperature ethane and propane decomposition 30th International Symposium on Combustion Oehlschlaeger, M. A., Davidson, D. F., Hanson, R. K. ELSEVIER SCIENCE INC. 2005: 1119–1127
  • Shock tube determination of ignition delay times in full-blend and surrogate fuel mixtures COMBUSTION AND FLAME Gauthier, B. M., Davidson, D. F., Hanson, R. K. 2004; 139 (4): 300-311
  • Ultraviolet absorption cross-sections of hot carbon dioxide CHEMICAL PHYSICS LETTERS Oehlschlaeger, M. A., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2004; 399 (4-6): 490-495
  • Interpreting shock tube ignition data INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., Hanson, R. K. 2004; 36 (9): 510-523

    View details for DOI 10.1002/kin.20024

    View details for Web of Science ID 000223297200006

  • Modern shock tube studies of combustion chemistry: Elementary reactions to large mechanisms. Meeting of the Division of Chemical Toxicology of the American-Chemical-Society held at the 228th National Meeting of the American-Chemical-Society Hanson, R. K., Davidson, D. F., Herbon, J. T., Oehlschlaeger, M. A., Vasudevan, V. AMER CHEMICAL SOC. 2004: U233–U233
  • High-temperature thermal decomposition of isobutane and n-butane behind shock waves JOURNAL OF PHYSICAL CHEMISTRY A Oehlschlaeger, M. A., Davidson, D. F., Hanson, R. K. 2004; 108 (19): 4247-4253

    View details for DOI 10.1021/jp0313627

    View details for Web of Science ID 000221302900012

  • Validation of a thermal decomposition mechanism of formaldehyde by detection of CH2O and HCO behind shock waves INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Friedrichs, G., Davidson, D. F., Hanson, R. K. 2004; 36 (3): 157-169

    View details for DOI 10.1002/kin.10183

    View details for Web of Science ID 000189245700003

  • Shock tube measurements of branched alkane ignition times and OH concentration time histories INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Oehlschlaeger, M. A., Davidson, D. F., Herbon, J. T., Hanson, R. K. 2004; 36 (2): 67-78

    View details for DOI 10.1002/kin.10173

    View details for Web of Science ID 000188088300001

  • Direct measurements of the reaction H+CH2O -> H-2+HCO behind shock waves by means of Vis-UV detection of formaldehyde INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Friedrichs, G., Davidson, D. F., Hanson, R. K. 2002; 34 (6): 374-386
  • Ultraviolet absorption spectra of shock-heated carbon dioxide and water between 900 and 3050 K CHEMICAL PHYSICS LETTERS Schulz, C., Koch, J. D., Davidson, D. F., Jeffries, J. B., Hanson, R. K. 2002; 355 (1-2): 82-88
  • Study of the high-temperature autoignition of n-alkane/O-2/Ar mixtures JOURNAL OF PROPULSION AND POWER Horning, D. C., Davidson, D. F., Hanson, R. K. 2002; 18 (2): 363-371
  • Shock tube measurements of iso-octane ignition times and OH concentration time histories 29th International Combustion Symposium Davidson, D. F., Oehlschlaeger, M. A., Herbon, J. T., Hanson, R. K. ELSEVIER SCIENCE INC. 2002: 1295–1301
  • Impact of UV absorption by CO2 and H2O on NO LIF in high-pressure combustion applications 29th International Combustion Symposium Schulz, C., Jeffries, J. B., Davidson, D. F., Koch, J. D., Wolfrum, J., Hanson, R. K. ELSEVIER SCIENCE INC. 2002: 2735–2742
  • Quantitative detection of HCO behind shock waves: The thermal decomposition of HCO PHYSICAL CHEMISTRY CHEMICAL PHYSICS Friedrichs, G., Herbon, J. T., Davidson, D. F., Hanson, R. K. 2002; 4 (23): 5778-5788

    View details for DOI 10.1039/b205692e

    View details for Web of Science ID 000179237500011

  • OH concentration time histories in n-alkane oxidation INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., Herbon, J. T., Horning, D. C., Hanson, R. K. 2001; 33 (12): 775-783
  • Measurements of temperature-dependent argon-broadened half-widths of H2O transitions in the 7117 cm(-1) region JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Nagali, V., Davidson, D. F., Hanson, R. K. 2000; 64 (6): 651-655
  • Shock tube measurements of jp-10 ignition 28th International Symposium on Combustion Davidson, D. F., Horning, D. C., Herbon, J. T., Hanson, R. K. ELSEVIER SCIENCE INC. 2000: 1687–1692
  • Shock-tube study of high-pressure H2O spectroscopy APPLIED OPTICS Nagali, V., Herbon, J. T., Horning, D. C., Davidson, D. F., Hanson, R. K. 1999; 38 (33): 6942-6950

    Abstract

    Water-vapor absorption features near 7117, 7185, and 7462 cm(-1) were probed at pressures to 65 atm (1 atm = 760 Torr) and temperatures to 1800 K in shock-heated mixtures of H(2)O in N(2) and Ar with a diode-laser source. Calculated absorbances based on Voigt line shapes and measured line parameters were in good agreement, within 10%, with measured absorbances at 7185.4 and 7117.4 cm(-1). We obtained temperature-dependent N(2) and Ar shift parameters for H(2)O absorption features by shifting the calculated spectra to match the recorded absorption scan. Absorbance simulations based on line parameters from HITRAN and HITEMP were found to be similar over the range of temperatures 600-1800 K and were within 25% of the measurements. The combined use of Toth's [Appl. Opt. 36, 4851 (1994)] line positions and strengths and HITRAN broadening parameters resulted in calculated absorption coefficients that were within 15% of the measurements at all three probed wavelengths.

    View details for Web of Science ID 000083743900019

    View details for PubMedID 18324237

  • Sensitive detection of NH2 in shock tube experiments using frequency modulation spectroscopy INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Votsmeier, M., Song, S., Davidson, D. F., Hanson, R. K. 1999; 31 (6): 445-453
  • Shock tube study of monomethylamine thermal decomposition and NH2 high temperature absorption coefficient INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Votsmeier, M., Song, S., Davidson, D. F., Hanson, R. K. 1999; 31 (5): 323-330
  • Kinetics modeling of shock-induced ignition in low-dilution CH4/O-2 mixtures at high pressures and intermediate temperatures COMBUSTION AND FLAME Petersen, E. L., Davidson, D. F., Hanson, R. K. 1999; 117 (1-2): 272-290
  • Ignition delay times of ram accelerator CH4/O-2/diluent mixtures AIAA/ASME/SAE/ASEE 32nd Joint Propulsion Conference Petersen, E. L., Davidson, D. F., Hanson, R. K. AMER INST AERONAUT ASTRONAUT. 1999: 82–91
  • Shock tube measurements of the equation of state of argon 13th Symposium on Thermophysical Properties Davidson, D. F., Bates, R., Petersen, E. L., Hanson, R. K. SPRINGER/PLENUM PUBLISHERS. 1998: 1585–94
  • CH-radical concentration measurements in fuel-rich CH4/O-2/Ar and CH4/O-2/NO/Ar mixtures behind shock waves COMBUSTION AND FLAME Woiki, D., Votsmeier, M., Davidson, D. F., Hanson, R. K., Bowman, C. T. 1998; 113 (4): 624-626
  • GRI-MECH - A comprehensively optimized detailed reaction mechanism for natural gas combustion and no formation and reburning. Frenklach, M., Goldenberg, M., Bowman, C. T., Hanson, R. K., Davidson, D. F., LISSIANSKI, V., GARDINER, W. C., Smith, G. P. AMER CHEMICAL SOC. 1998: U164–U165
  • Measurement of the rate coefficient of the reaction CH+O-2->products in the temperature range 2200 to 2600 K INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Rohrig, M., Petersen, E. L., Davidson, D. F., Hanson, R. K., Bowman, C. T. 1997; 29 (10): 781-789
  • A shock tube study of the pyrolysis of NO2 INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Rohrig, M., Petersen, E. L., Davidson, D. F., Hanson, R. K. 1997; 29 (7): 483-493
  • The pressure dependence of the thermal decomposition of N2O INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Rohrig, M., Petersen, E. L., Davidson, D. F., Hanson, R. K. 1996; 28 (8): 599-608
  • Measurements of the OH A-X (0,0) 306nm absorption bandhead at 60atm and 1735K JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Davidson, D. F., Roehrig, M., Petersen, E. L., DIROSA, M. D., Hanson, R. K. 1996; 55 (6): 755-762
  • High-pressure methane oxidation behind reflected shock waves 26th International Symposium on Combustion Petersen, E. L., Rohrig, M., Davidson, D. F., Hanson, R. K., Bowman, C. T. COMBUSTION INSTITUTE. 1996: 799–806
  • Real gas corrections in shock tube studies at high pressures ISRAEL JOURNAL OF CHEMISTRY Davidson, D. F., Hanson, R. K. 1996; 36 (3): 321-326
  • A SHOCK-TUBE STUDY OF METHYL-METHYL REACTIONS BETWEEN 1200 AND 2400 K INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., DIROSA, M. D., Chang, E. J., Hanson, R. K., Bowman, C. T. 1995; 27 (12): 1179-1196
  • COMMUNICATION - REVISED VALUES FOR THE RATE COEFFICIENTS OF ETHANE AND METHANE DECOMPOSITION INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., Hanson, R. K., Bowman, C. T. 1995; 27 (3): 305-308
  • VUV ABSORPTION DIAGNOSTIC FOR SHOCK-TUBE KINETICS STUDIES OF C2H4 JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Zelson, L. S., Davidson, D. F., Hanson, R. K. 1994; 52 (1): 31-43
  • A STUDY OF ETHANE DECOMPOSITION IN A SHOCK-TUBE USING LASER-ABSORPTION OF CH3 INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., DIROSA, M. D., Hanson, R. K., Bowman, C. T. 1993; 25 (11): 969-982
  • A CW LASER-ABSORPTION DIAGNOSTIC FOR METHYL RADICALS JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Davidson, D. F., Chang, A. Y., DIROSA, M. D., Hanson, R. K. 1993; 49 (5): 559-571
  • SHOCK-TUBE MEASUREMENTS OF THE REACTIONS OF CN WITH O AND O2 INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., Dean, A. J., DIROSA, M. D., Hanson, R. K. 1991; 23 (11): 1035-1050
  • RAPID TUNING CW LASER TECHNIQUE FOR MEASUREMENTS OF GAS VELOCITY, TEMPERATURE, PRESSURE, DENSITY, AND MASS FLUX USING NO APPLIED OPTICS Chang, A. Y., DIROSA, M. D., Davidson, D. F., Hanson, R. K. 1991; 30 (21): 3011-3022

    Abstract

    An intracavity-doubled rapid-tuning cw ring dye laser was used to acquire fully resolved absorption profiles of NO line pairs in the A ? X band at 225 nm at a rate of 4 kHz. These profiles were utilized for simultaneous measurements of flow parameters in the high speed 1-D flows generated in a shock tube. Velocity was determined from the Doppler shift measured using a pair of profiles simultaneously acquired at different angles with respect to the flow direction. Temperature was determined from the intensity ratio of the adjacent lines. Pressure and density were found both from the collisional broadening and the fractional absorption. From this information the mass flux was determined. The results compare well to 1-D shock calculations.

    View details for Web of Science ID A1991FX92000020

    View details for PubMedID 20706349

  • CONTINUOUS WAVE LASER-ABSORPTION TECHNIQUES FOR GASDYNAMIC MEASUREMENTS IN SUPERSONIC FLOWS APPLIED OPTICS Davidson, D. F., Chang, A. Y., DIROSA, M. D., Hanson, R. K. 1991; 30 (18): 2598-2608

    Abstract

    Line-of-sight measurements of velocity, temperature, pressure, density, and mass flux were performed in a transient shock tube flow using three laser absorption schemes. All methods employed an intracavity-doubled ring dye laser tuned to an OH transition in the A(2) summation operator(+) ? X(2)II (0,0) band at 306 nm. In the first scheme, the gas was labeled by 193.3-nm excimer photolysis of H(2)O, and the passage of the generated OH was detected downstream. In the second method, the laser was tuned at a rate of 3 kH(z) over the R(1)(7) and R(1)(11) line pair, and absorption was simultaneously monitored at 90 and 60 degrees with respect to the flow. Velocity was determined from the Doppler shift of the profiles and the temperature from the intensity ratio of the lines. Pressure was determined from both the magnitude of absorption and the collisional broadening. In the third method, the laser wavelength was fixed at a single frequency, and a continuous measurement of velocity and pressure was obtained using the signals from the two beam paths. All methods gave results which compare favorably to calculated values.

    View details for Web of Science ID A1991FR74000028

    View details for PubMedID 20700249

  • A SHOCK-TUBE STUDY OF REACTIONS OF C ATOMS WITH H-2 AND O2 USING EXCIMER PHOTOLYSIS OF C3O2 AND C ATOM ATOMIC RESONANCE-ABSORPTION SPECTROSCOPY JOURNAL OF PHYSICAL CHEMISTRY Dean, A. J., Davidson, D. F., Hanson, R. K. 1991; 95 (1): 183-191
  • HIGH-TEMPERATURE REACTION-RATE COEFFICIENTS DERIVED FROM N-ATOM ARAS MEASUREMENTS AND EXCIMER PHOTOLYSIS OF NO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., Hanson, R. K. 1990; 22 (8): 843-861
  • A PYROLYSIS MECHANISM FOR AMMONIA INTERNATIONAL JOURNAL OF CHEMICAL KINETICS Davidson, D. F., KOHSEHOINGHAUS, K., Chang, A. Y., Hanson, R. K. 1990; 22 (5): 513-535
  • SHOCK-TUBE EXCIMER PHOTOLYSIS AND THE MEASUREMENT OF N ATOM KINETIC RATES 17TH INTERNATIONAL SYMP ON SHOCK WAVES AND SHOCK TUBES Davidson, D. F., Snell, D. C., Hanson, R. K. AIP PRESS. 1990: 525–530
  • C-ATOM ARAS DIAGNOSTIC FOR SHOCK-TUBE KINETICS STUDIES 17TH INTERNATIONAL SYMP ON SHOCK WAVES AND SHOCK TUBES Dean, A. J., Davidson, D. F., Hanson, R. K. AIP PRESS. 1990: 537–542
  • HIGH-TEMPERATURE ABSORPTION-COEFFICIENTS OF O-2, NH3, AND H2O FOR BROAD-BAND ARF EXCIMER LASER-RADIATION JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Davidson, D. F., Chang, A. Y., KOHSEHOINGHAUS, K., Hanson, R. K. 1989; 42 (4): 267-278
  • QUANTITATIVE NH2 CONCENTRATION DETERMINATION IN SHOCK-TUBE LASER-ABSORPTION EXPERIMENTS JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER KOHSEHOINGHAUS, K., Davidson, D. F., Chang, A. Y., Hanson, R. K. 1989; 42 (1): 1-17
  • Laser Photolysis Shock Tube for Combustion Kinetics Studies Twenty-Second Symposium (International) on Combustion Davidson, D. F., Chang, A. Y., Hanson, R. K. 1988