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Chattopadhyay A, Bedjanian Y, Romanias MN, Eleftheriou AD, Melissas VS, Papadimitriou VC, Burkholder JB. OH Radical and Chlorine Atom Kinetics of Substituted Aromatic Compounds: 4-chlorobenzotrifluoride ( p-ClC 6H 4CF 3). J Phys Chem A 2022; 126:5407-5419. [PMID: 35943137 DOI: 10.1021/acs.jpca.2c04455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mechanisms for the OH radical and Cl atom gas-phase reaction kinetics of substituted aromatic compounds remain a topic of atmospheric and combustion chemistry research. 4-Chlorobenzotrifluoride (p-chlorobenzotrifluoride, p-ClC6H4CF3, PCBTF) is a commonly used substituted aromatic volatile organic compound (VOC) in solvent-based coatings. As such, PCBTF is classified as a volatile chemical product (VCP) whose release into the atmosphere potentially impacts air quality. In this study, rate coefficients, k1, for the OH + PCBTF reaction were measured over the temperature ranges 275-340 and 385-940 K using low-pressure discharge flow-tube reactors coupled with a mass spectrometer detector in the ICARE/CNRS (Orléans, France) laboratory. k1(298-353 K) was also measured using a relative rate method in the thermally regulated atmospheric simulation chamber (THALAMOS; Douai, France). k1(T) displayed a non-Arrhenius temperature dependence with a negative temperature dependence between 275 and 385 K given by k1(275-385 K) = (1.50 ± 0.15) × 10-14 exp((705 ± 30)/T) cm3 molecule-1 s-1, where k1(298 K) = (1.63 ± 0.03) × 10-13 cm3 molecule-1 s-1 and a positive temperature dependence at elevated temperatures given by k1(470-950 K) = (5.42 ± 0.40) × 10-12 exp(-(2507 ± 45) /T) cm3 molecule-1 s-1. The present k1(298 K) results are in reasonable agreement with two previous 296 K (760 Torr, syn. air) relative rate measurements. The rate coefficient for the Cl-atom + PCBTF reaction, k2, was also measured in THALAMOS using a relative rate technique that yielded k2(298 K) = (7.8 ± 2) × 10-16 cm3 molecule-1 s-1. As part of this work, the UV and infrared absorption spectra of PCBTF were measured (NOAA; Boulder, CO, USA). On the basis of the UV absorption spectrum, the atmospheric instantaneous UV photolysis lifetime of PCBTF (ground level, midlatitude, Summer) was estimated to be 3-4 days, assuming a unit photolysis quantum yield. The non-Arrhenius behavior of the OH + PCBTF reaction over the temperature range 275 to 950 K is interpreted using a mechanism for the formation of an OH-PCBTF adduct and its thermochemical stability. The results from this study are included in a discussion of the OH radical and Cl atom kinetics of halogen substituted aromatic compounds for which only limited temperature-dependent kinetic data are available.
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Affiliation(s)
- Aparajeo Chattopadhyay
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305-3327, United States.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Yuri Bedjanian
- Institut de Combustion, Aérothermique, Réactivité et Environnement (ICARE), CNRS 45071 Orléans Cedex 2, France
| | - Manolis N Romanias
- Center for Energy and Environment, Institut Mines-Télécom Nord Europe, Université Lille, F-59000 Lille, France
| | - Angeliki D Eleftheriou
- Laboratory of Photochemistry and Chemical Kinetics, Department of Chemistry, University of Crete, Vassilika Vouton, 70013, Heraklion, Crete, Greece
| | | | - Vassileios C Papadimitriou
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305-3327, United States.,Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States.,Laboratory of Photochemistry and Chemical Kinetics, Department of Chemistry, University of Crete, Vassilika Vouton, 70013, Heraklion, Crete, Greece
| | - James B Burkholder
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305-3327, United States
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Jha DK, Vinithkumar NV, Sahu BK, Dheenan PS, Das AK, Begum M, Devi MP, Kirubagaran R. Multivariate and geo-spatial approach for seawater quality of Chidiyatappu Bay, south Andaman Islands, India. MARINE POLLUTION BULLETIN 2015; 96:463-470. [PMID: 25972234 DOI: 10.1016/j.marpolbul.2015.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 04/18/2015] [Accepted: 05/02/2015] [Indexed: 06/04/2023]
Abstract
Chidiyatappu Bay is one of the least disturbed marine environments of Andaman & Nicobar Islands, the union territory of India. Oceanic flushing from southeast and northwest direction is prevalent in this bay. Further, anthropogenic activity is minimal in the adjoining environment. Considering the pristine nature of this bay, seawater samples collected from 12 sampling stations covering three seasons were analyzed. Principal Component Analysis (PCA) revealed 69.9% of total variance and exhibited strong factor loading for nitrite, chlorophyll a and phaeophytin. In addition, analysis of variance (ANOVA-one way), regression analysis, box-whisker plots and Geographical Information System based hot spot analysis further simplified and supported multivariate results. The results obtained are important to establish reference conditions for comparative study with other similar ecosystems in the region.
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Affiliation(s)
- Dilip Kumar Jha
- Ocean Science and Technology for Islands, ESSO-NIOT, Ministry of Earth Science, Government of India, Chennai 600100, India; Andaman and Nicobar Centre for Ocean Science and Technology, Earth System Sciences Organisation (ESSO)-National Institute of Ocean Technology (NIOT), Ministry of Earth Sciences, Government of India, Port Blair 744103, India.
| | - Nambali Valsalan Vinithkumar
- Andaman and Nicobar Centre for Ocean Science and Technology, Earth System Sciences Organisation (ESSO)-National Institute of Ocean Technology (NIOT), Ministry of Earth Sciences, Government of India, Port Blair 744103, India
| | - Biraja Kumar Sahu
- Department of Marine Sciences, Berhampur University, Berhampur 760007, Odisha, India
| | - Palaiya Sukumaran Dheenan
- Andaman and Nicobar Centre for Ocean Science and Technology, Earth System Sciences Organisation (ESSO)-National Institute of Ocean Technology (NIOT), Ministry of Earth Sciences, Government of India, Port Blair 744103, India
| | - Apurba Kumar Das
- Andaman and Nicobar Centre for Ocean Science and Technology, Earth System Sciences Organisation (ESSO)-National Institute of Ocean Technology (NIOT), Ministry of Earth Sciences, Government of India, Port Blair 744103, India
| | - Mehmuna Begum
- Andaman and Nicobar Centre for Ocean Science and Technology, Earth System Sciences Organisation (ESSO)-National Institute of Ocean Technology (NIOT), Ministry of Earth Sciences, Government of India, Port Blair 744103, India
| | - Marimuthu Prashanthi Devi
- Department of Environmental Management, School of Environmental Sciences, Bharathidasan University, India
| | - Ramalingam Kirubagaran
- Ocean Science and Technology for Islands, ESSO-NIOT, Ministry of Earth Science, Government of India, Chennai 600100, India
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