Rates of OH Radical Reactions. I. Reactions with H2, CH4, C2H6, and C3H8 at 295 K

Overend, R. P.; Paraskevopoulos, G.; Cvetanović, R. J.

doi:10.1139/v75-482

Cited by 63 publications

(24 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The apparatus and experimental technique have been described in detail before (5,6), and will be mentioned here briefly. The apparatus consists of a fast flash photolysis system coupled to a spectrophotometric detection system.…”

Section: Methodsmentioning

confidence: 99%

“…The flash lamp was operated at discharge energies of 60 and 150 J. The OH concentration was monitored by following the time-resolved attenuation of the OH resonance radiation (Q:)' rotational line of the (0,O) band of the A'C' + X'n transition) produced by a microwave discharge in a flowing low pressure Ar/H,O mixture, as described before (5,6). Signal averaging was used to improve the signal-to-noise ratio.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

A kinetic study of the reactions of OH radicals with fluoroethanes. Estimates of C—H bond strengths in fluoroalkanes

Martin¹,

Paraskevopoulos²

1983

Can. J. Chem.

View full text Add to dashboard Cite

PARASKEVOPOULOS. Can. J. Chem. 61, 861 (1983). A kinetic study of the reactions of OH radicals with a series of fluoroethanes in the gas phase is prcsented. OH radicals were generated by flash photolysis of H 2 0 vapor in the vacuum uv (A > 165 nm) and were monitored in absorption by timc-rcsolved attenuation of resonance radiation at 308.15 nm [OH(A'C' + X'n)]. The following absolute rate constants (in units of 10%m3 mol-' s-I at the 95% confidence limit) were determined at 298 K: kcli2rcli,r = 67.7 + 7.2, kC~2FClIF2 = 11.0 + 1.1, ~C H~C F~ = 1.03 20.26, kCHZFCFl = 3.10 2 0.35. kCHF2CF3 = 1.50 I+--0.17. From a linear correlation of the present and previously published rate constants with bond dissociation energies, the following quantities (in kcal mol-' at 298 K) were estimated to be: D(CH,CHF-H) = 96.3 5 .1.5, D(CH,FCHF-H = 98.8 5 .

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

A kinetic study of the reactions of OH radicals with fluoroethanes. Estimates of C—H bond strengths in fluoroalkanes

Martin¹,

Paraskevopoulos²

1983

Can. J. Chem.

View full text Add to dashboard Cite

show abstract

“…The potential for interaction with the hydroxyl radical (OH), the main sink of CH 4 , is neglected. A calculation assuming an above-average OH mole fraction over a rural region of 0.5 pptv (Stone et al, 2012) and a reaction rate of 6.5 × 10 −15 (Overend et al, 1975) produces a CH 4 sink of 0.5 ppb h −1 . The duration of a flight can be up to 3 h, leading to a potential loss of 1.5 ppb over the course of a flight.…”

Section: Transport Modelmentioning

confidence: 99%

Quantifying methane emissions from natural gas production in north-eastern Pennsylvania

et al. 2017

View full text Add to dashboard Cite

Abstract. Natural gas infrastructure releases methane (CH 4 ), a potent greenhouse gas, into the atmosphere. The estimated emission rate associated with the production and transportation of natural gas is uncertain, hindering our understanding of its greenhouse footprint. This study presents a new application of inverse methodology for estimating regional emission rates from natural gas production and gathering facilities in north-eastern Pennsylvania. An inventory of CH 4 emissions was compiled for major sources in Pennsylvania. This inventory served as input emission data for the Weather Research and Forecasting model with chemistry enabled (WRFChem), and atmospheric CH 4 mole fraction fields were generated at 3 km resolution. Simulated atmospheric CH 4 enhancements from WRF-Chem were compared to observations obtained from a 3-week flight campaign in May 2015. Modelled enhancements from sources not associated with upstream natural gas processes were assumed constant and known and therefore removed from the optimization procedure, creating a set of observed enhancements from natural gas only. Simulated emission rates from unconventional production were then adjusted to minimize the mismatch between aircraft observations and model-simulated mole fractions for 10 flights. To evaluate the method, an aircraft mass balance calculation was performed for four flights where conditions permitted its use. Using the model optimization approach, the weighted mean emission rate from unconventional natural gas production and gathering facilities in northeastern Pennsylvania approach is found to be 0.36 % of total gas production, with a 2σ confidence interval between 0.27 and 0.45 % of production. Similarly, the mean emission estimates using the aircraft mass balance approach are calculated to be 0.40 % of regional natural gas production, with a 2σ confidence interval between 0.08 and 0.72 % of production. These emission rates as a percent of production are lower than rates found in any other basin using a top-down methodology, and may be indicative of some characteristics of the basin that make sources from the north-eastern Marcellus region unique.

show abstract

“…The technique was improved by using resonance absorption [18,19], (FP-RA), or resonance fluorescence [20] (FP-RF) for the detection of OH, fast electronics for the time resolution of the signal, signal averaging, and processing the data by an on line computer. Recently flash lamps and resonance lamps are being replaced by lasers as photolytic and analytic light sources.…”

Section: A Direct Techniquesmentioning

confidence: 99%

Reactions of OH radicals with inorganic compounds in the gas phase

Paraskevopoulos

Singleton

1988

Reviews of Chemical Intermediates

Self Cite

View full text Add to dashboard Cite

Rates of OH Radical Reactions. I. Reactions with H₂, CH₄, C₂H₆, and C₃H₈ at 295 K

Cited by 63 publications

References 4 publications

A kinetic study of the reactions of OH radicals with fluoroethanes. Estimates of C—H bond strengths in fluoroalkanes

A kinetic study of the reactions of OH radicals with fluoroethanes. Estimates of C—H bond strengths in fluoroalkanes

Quantifying methane emissions from natural gas production in north-eastern Pennsylvania

Reactions of OH radicals with inorganic compounds in the gas phase

Contact Info

Product

Resources

About