Kinetics and Mechanism of the Reaction of the Hydroxyl Radical withh8-Isoprene andd8-Isoprene:  Isoprene Absorption Cross Sections, Rate Coefficients, and the Mechanism of Hydroperoxyl Radical Production

2004 ◽  
Vol 108 (9) ◽  
pp. 1537-1551 ◽  
Author(s):  
P. Campuzano-Jost ◽  
M. B. Williams ◽  
L. D'Otton ◽  
A. J. Hynes
ChemInform ◽  
2010 ◽  
Vol 22 (42) ◽  
pp. no-no
Author(s):  
R. TALUKDAR ◽  
A. MELLOUKI ◽  
T. GIERCZAK ◽  
J. B. BURKHOLDER ◽  
S. A. MCKEEN ◽  
...  

2016 ◽  
Vol 120 (45) ◽  
pp. 9049-9062 ◽  
Author(s):  
Antonia G. Zogka ◽  
Abdelwahid Mellouki ◽  
Manolis N. Romanias ◽  
Yuri Bedjanian ◽  
Mahmoud Idir ◽  
...  

2012 ◽  
Vol 116 (24) ◽  
pp. 6041-6050 ◽  
Author(s):  
María Antiñolo ◽  
Sergio González ◽  
Bernabé Ballesteros ◽  
José Albaladejo ◽  
Elena Jiménez

2017 ◽  
Author(s):  
Terry J. Dillon ◽  
Katrin Dulitz ◽  
Christoph M. B. Gross ◽  
John N. Crowley

Abstract. Abstract. Pulsed laser methods for OH generation and detection were used to study atmospheric degradation reactions for three important biogenic gases: OH + isoprene (R1); OH + α-pinene (R2); and OH + Δ-3-carene (R3). Gas-phase rate coefficients were characterised by non-Arrhenius kinetics for all three reactions. For (R1), k1 (241–356 K) = (1.93 ± 0.08) × 10−11 exp (466 ± 12)/T cm3 molecule−1 s−1 was determined, with a room temperature value of k1 (297 K) = (9.3 ± 0.4) × 10−11 cm3 molecule−1 s−1, independent of bath-gas pressure (5–200 Torr) and composition (M = N2 or air). Accuracy and precision were enhanced by online optical monitoring of isoprene, with absolute concentrations obtained via an absorption cross-section, σisoprene = (1.28 ± 0.06) × 10−17 cm2 molecule−1 at λ = 184.95 nm, determined in this work. These results indicate that significant discrepancies between previous absolute and relative rate determinations of k1 result in part from σ values used to derive the isoprene concentration. Similar methods were used to determine rate coefficients (in 10−11 cm3 molecule−1 s−1) for (R2–R3): k2 (238–357 K) = (1.83 ± 0.04) × exp (330 ± 6)/T; and k3 (235–357 K) = (2.48 ± 0.14) × exp (357 ± 17)/T. This is the first temperature-dependent dataset for (R3) and enables the calculation of reliable atmospheric lifetimes with respect to OH removal for e.g. boreal forest springtime conditions. Room temperature values of k2 (296 K) = (5.4 ± 0.2) × 10−11 cm3 molecule−1 s−1 and k3 (297 K) = (8.1 ± 0.3) × 10−11 cm3 molecule−1 s−1 were independent of bath-gas pressure (7–200 Torr, N2 or air), and in good agreement with previously reported values. In the course of this work, 184.95 nm absorption cross-sections were determined: σ = (1.54 ± 0.08) × 10−17cm 2 molecule−1 for α-pinene and (2.40 ± 0.12) × 10−17  cm2 molecule−1 for Δ-3-carene.


2004 ◽  
Vol 70 (3) ◽  
Author(s):  
A. M. C. Sobrinho ◽  
N. B. H. Lozano ◽  
M.-T. Lee

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