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Lewis T, Heard DE, Blitz MA. A novel multiplex absorption spectrometer for time-resolved studies. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:024101. [PMID: 29495797 DOI: 10.1063/1.5006539] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A Time-Resolved Ultraviolet/Visible (UV/Vis) Absorption Spectrometer (TRUVAS) has been developed that can simultaneously monitor absorption at all wavelengths between 200 and 800 nm with millisecond time resolution. A pulsed photolysis laser (KrF 248 nm) is used to initiate chemical reactions that create the target species. The absorption signals from these species evolve as the composition of the gas in the photolysis region changes over time. The instrument can operate at pressures over the range ∼10-800 Torr and can measure time-resolved absorbances <10-4 in the UV (300 nm) and even lower in the visible (580 nm) 2.3 × 10-5, with the peak of sensitivity at ∼500 nm. The novelty of this setup lies in the arrangement of the multipass optics. Although appearing similar to other multipass optical systems (in particular the Herriott cell), there are fundamental differences, most notably the ability to adjust each mirror to maximise the overlap between the probe beam and the photolysis laser. Another feature which aids the sensitivity and versatility of the system is the use of 2 high-throughput spectrographs coupled with sensitive line-array CCDs, which can measure absorbance from ∼200 to 800 nm simultaneously. The capability of the instrument is demonstrated via measurements of the absorption spectrum of the peroxy radical, HOCH2CH2O2, and its self-reaction kinetics.
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Affiliation(s)
- Thomas Lewis
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Dwayne E Heard
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Mark A Blitz
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom
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2
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Yan C, Kocevska S, Krasnoperov LN. Kinetics of the Reaction of CH3O2 Radicals with OH Studied over the 292–526 K Temperature Range. J Phys Chem A 2016; 120:6111-21. [DOI: 10.1021/acs.jpca.6b04213] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chao Yan
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology,
University Heights, Newark, New Jersey 07102, United States
| | - Stefani Kocevska
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology,
University Heights, Newark, New Jersey 07102, United States
| | - Lev N. Krasnoperov
- Department of Chemistry and Environmental Science, New Jersey Institute of Technology,
University Heights, Newark, New Jersey 07102, United States
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3
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Sangwan M, Yan C, Chesnokov EN, Krasnoperov LN. Reaction CH3 + CH3 → C2H6 Studied over the 292–714 K Temperature and 1–100 bar Pressure Ranges. J Phys Chem A 2015; 119:7847-57. [DOI: 10.1021/acs.jpca.5b01276] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Manuvesh Sangwan
- Department
of Chemistry and Environmental Science, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, United States
| | - Chao Yan
- Department
of Chemistry and Environmental Science, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, United States
| | | | - Lev N. Krasnoperov
- Department
of Chemistry and Environmental Science, New Jersey Institute of Technology, University Heights, Newark, New Jersey 07102, United States
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4
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Alarcón P, Bohn B, Zetzsch C, Rayez MT, Rayez JC. Reversible addition of the OH radical to p-cymene in the gas phase: multiple adduct formation. Part 2. Phys Chem Chem Phys 2014; 16:17315-26. [DOI: 10.1039/c4cp02073a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Four adduct isomers can be formed in the OH + p-cymene reaction. Experiments reveal formation of at least two distinguishable adducts in agreement with theoretical predictions that mainly the two ortho-adducts are formed.
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Affiliation(s)
- Paulo Alarcón
- Atmospheric Chemistry Research Laboratory
- University of Bayreuth
- , Germany
| | - Birger Bohn
- Institut für Energie - und Klimaforschung IEK-8: Troposphäre
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Cornelius Zetzsch
- Atmospheric Chemistry Research Laboratory
- University of Bayreuth
- , Germany
- Fraunhofer Institute for Toxicology and Experimental Medicine
- 30625 Hannover, Germany
| | - Marie-Thérèse Rayez
- Institut des Sciences Moleculaires
- Université de Bordeaux
- 33405 Talence, France
| | - Jean-Claude Rayez
- Institut des Sciences Moleculaires
- Université de Bordeaux
- 33405 Talence, France
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5
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Loison JC, Rayez MT, Rayez JC, Gratien A, Morajkar P, Fittschen C, Villenave E. Gas-Phase Reaction of Hydroxyl Radical with Hexamethylbenzene. J Phys Chem A 2012. [DOI: 10.1021/jp307568c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jean-Christophe Loison
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Marie-Thérèse Rayez
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Jean-Claude Rayez
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Aline Gratien
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Pranay Morajkar
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
- Universite Lille, PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
- CNRS,
PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
| | - Christa Fittschen
- Universite Lille, PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
- CNRS,
PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
| | - Eric Villenave
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
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6
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Jain C, Morajkar P, Schoemaecker C, Fittschen C. Formation of HO2 radicals from the 248 nm two-photon excitation of different aromatic hydrocarbons in the presence of O2. J Phys Chem A 2012; 116:6231-9. [PMID: 22500669 DOI: 10.1021/jp211520g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The excitation energy dependence of HO(2) radical formation from the 248 nm irradiation of four different aromatic hydrocarbons (benzene, toluene, o-xylene, and mesitylene) in the presence of O(2) has been studied. HO(2) has been monitored at 6638.20 cm(-1) by cw-CRDS, and the formation of a short-lived, unidentified species, showing broad-band absorption around the HO(2) absorption line, has been observed. For all four hydrocarbons, the same HO(2) formation pattern has been observed: HO(2) is formed immediately on our time scale after the excitation pulse, followed by a formation of more HO(2) on a much longer time scale. Taking into account the absorption of the short-lived species, the yields of both types of HO(2) radicals are in agreement with a formation following 2-photon absorption by the aromatic hydrocarbons. The yields do not much depend on the nature of the aromatic hydrocarbon. For practical use in past and future experiments on aromatic hydrocarbons, an empirical value is given, allowing the estimation of the total concentration of HO(2) radicals formed at 40 Torr He in the presence of around [O(2)] = 1 × 10(17)cm(-3) as a function of the 248 nm excitation energy: [HO(2)]/[aromatic hydrocarbon] ≈ 2 × 10(-6) × E(2) (with E in mJ cm(-2)).
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Affiliation(s)
- Chaithanya Jain
- Université Lille Nord de France PhysicoChimie des Processus de Combustion et de l'Atmosphère, PC2A CNRS Université Lille 1, UMR 8522, F-59650 Villeneuve d'Ascq, France
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7
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Bohn B, Zetzsch C. Kinetics and mechanism of the reaction of OH with the trimethylbenzenes – experimental evidence for the formation of adduct isomers. Phys Chem Chem Phys 2012; 14:13933-48. [DOI: 10.1039/c2cp42434g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Raff JD, Hites RA. Gas-Phase Reactions of Brominated Diphenyl Ethers with OH Radicals. J Phys Chem A 2006; 110:10783-92. [PMID: 16970372 DOI: 10.1021/jp0630222] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A small volume reaction chamber coupled to a mass spectrometer was used to study the gas-phase kinetics and mechanism of the reaction of OH radicals with diphenyl ether and seven polybrominated diphenyl ethers (PBDEs) with 1-2 bromines. Relative rate constants for these reactions were determined using isopropyl nitrite photolysis in He-air mixtures at approximately 740 Torr between the temperatures of 326-388 K. The Arrhenius expression for each compound was used to extrapolate the following OH rate constants at 298 K (in units of 10(-12) cm3 molecule(-1) s(-1), with 95% confidence intervals): diphenyl ether, 7.45 +/- 0.13; 2-bromodiphenyl ether, 4.7; 3-bromodiphenyl ether, 4.6; 4-bromodiphenyl ether, 5.7; 2,2'-dibromodiphenyl ether, 1.3; 2,4-dibromodiphenyl ether, 3.8; 3,3-dibromodiphenyl ether, 3.2; and 4,4'-bromodiphenyl ether, 5.1. The measured OH rate constants are in reasonable agreement with those predicted by structure activity relationships. Positive temperature dependences of these OH rate constants are observed for all compounds measured except for diphenyl ether and 4,4'-dibromodiphenyl ether. Bromophenols (in yields up to 20% relative to the amount of PBDE consumed) and Br2 were characterized as products of these reactions, suggesting that OH addition to ipso positions of these brominated aryls may be an important reaction pathway.
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Affiliation(s)
- Jonathan D Raff
- School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, USA
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Coeur-Tourneur C, Henry F, Janquin MA, Brutier L. Gas-phase reaction of hydroxyl radicals withm-,o- andp-cresol. INT J CHEM KINET 2006. [DOI: 10.1002/kin.20186] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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