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Tayum N, Murugan A, Deka RC, Gour NK, Mishra BK. The molecular level study of the fate of the CH 3CH 2C(O)OCH(O)CH 3 radical derived from ethyl propionate. MOLECULAR SIMULATION 2023. [DOI: 10.1080/08927022.2023.2189975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
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Wang S, Huo E, Guan Z, Cai S. Pyrolysis mechanism of HFO-1234yf/iso-butane mixture: ReaxFF reactive molecular dynamic simulation study. COMPUT THEOR CHEM 2023. [DOI: 10.1016/j.comptc.2023.114098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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Yadav AK, Mishra BK, Singh A, Gour NK. Atmospheric degradation, mechanism and kinetics of ethyl vinyl ketone (CH 2=CHCOCH 2CH 3) initiated by Cl atom: an insight from DFT study. Mol Phys 2022. [DOI: 10.1080/00268976.2022.2100835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
| | | | - Ashutosh Singh
- Department of Chemistry, K.S. Saket PG College, Ayodhya, India
| | - Nand Kishor Gour
- Department of Chemical Sciences, Tezpur University, Tezpur, India
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Lugo PL, Straccia VG, Rivela CB, Patroescu-Klotz I, Illmann N, Teruel MA, Wiesen P, Blanco MB. Diurnal photodegradation of fluorinated diketones (FDKs) by OH radicals using different atmospheric simulation chambers: Role of keto-enol tautomerization on reactivity. CHEMOSPHERE 2022; 286:131562. [PMID: 34315082 DOI: 10.1016/j.chemosphere.2021.131562] [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: 04/01/2021] [Revised: 07/05/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Rate coefficients for the gas-phase reactions of OH radicals with a series of fluorinated diketones have been determined for the first time at (298 ± 3) K and atmospheric pressure using the relative method and FTIR spectroscopy and GC-FID to monitor both reactants and references. The following values, in 10-11 cm3 molecule-1 s-1, were obtained for 1,1,1-trifluoro-2,4-pentanedione (TFP), 1,1,1-trifluoro-2,4-hexanedione (TFH) and 1,1,1-trifluoro-5-methyl-2,4-hexanedione (TFMH), respectively: k1(TFP + OH) = (1.3 ± 0.4), k2(TFH + OH) = (2.2 ± 0.8), k3(TFMH + OH) = (3.3 ± 1.0). The results are discussed with respect to the keto-enolic tautomerization specific for β-diketones. Based on the present results, the tropospheric lifetimes of TFP, TFH and TFMH upon degradation by OH radicals were calculated as 21, 13 and 8 h, respectively indicating that transport might play a role in the atmospheric fate of the studied compounds. Photochemical ozone creation potentials were estimated for TFP, TFH and TFMH to be: 23, 29 and 34, respectively.
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Affiliation(s)
- Pedro L Lugo
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire. Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), Dpto. de Fisicoquímica. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Ciudad Universitaria, 5000, Córdoba, Argentina
| | - V G Straccia
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire. Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), Dpto. de Fisicoquímica. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Cynthia B Rivela
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire. Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), Dpto. de Fisicoquímica. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Iulia Patroescu-Klotz
- Institute for Atmospheric and Environmental Research, Bergische Universität Wuppertal, 42097, Wuppertal, Germany
| | - Niklas Illmann
- Institute for Atmospheric and Environmental Research, Bergische Universität Wuppertal, 42097, Wuppertal, Germany
| | - Mariano A Teruel
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire. Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), Dpto. de Fisicoquímica. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Peter Wiesen
- Institute for Atmospheric and Environmental Research, Bergische Universität Wuppertal, 42097, Wuppertal, Germany
| | - Maria B Blanco
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire. Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), Dpto. de Fisicoquímica. Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Ciudad Universitaria, 5000, Córdoba, Argentina.
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Manonmani G, Sandhiya L, Senthilkumar K. Mechanism, Kinetics, and Ecotoxicity Assessment of ·OH-Initiated Oxidation Reactions of Sulfoxaflor. J Phys Chem A 2021; 125:10052-10064. [PMID: 34755512 DOI: 10.1021/acs.jpca.1c05030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ·OH-initiated reaction mechanism and kinetics of sulfoxaflor were investigated by using electronic structure calculations. The possible hydrogen atom and cyano group abstraction reaction pathways were studied, and the calculated thermochemical parameters show that the hydrogen atom abstraction from the C7 carbon atom is the more favorable reaction pathway. The subsequent reactions for the favorable intermediate (I4) with other atmospheric reactive species, such as O2, H2O, HO2·, and NOx· (x = 1, 2), were studied in detail. The products identified from the subsequent reactions could contribute to secondary organic aerosol (SOA) formation in the atmosphere. The intermediates and products formed from the initial and subsequent reactions are equally as toxic as the parent sulfoxaflor. At 298 K, the rate constant calculated for the formation of the favorable intermediate I4 is 2.54 × 10-12 cm3 molecule-1 s-1, which shows that the lifetime of sulfoxaflor is 54 h. The excited-state calculation performed through time-dependent density functional theory shows that the photolysis of the title molecule is unlikely in the atmosphere. The global warming potentials (GWPs) for different time horizons, photochemical ozone creation potential (POCP), and ecotoxicity analysis were also studied for the insecticide sulfoxaflor.
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Affiliation(s)
- G Manonmani
- Department of Physics, Bharathiar University, Coimbatore 641 046, Tamil Nadu, India
| | - L Sandhiya
- Council of Scientific and Industrial Research-National Institute of Science, Technology and Development Studies, New Delhi 110012, India
| | - K Senthilkumar
- Department of Physics, Bharathiar University, Coimbatore 641 046, Tamil Nadu, India
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Holtomo O, Mbigah MD, Nsangou M, Motapon O. Insight of UV-vis spectra and atmospheric implication for the reaction of ˙OH radical towards glyphosate herbicide and its hydrates. RSC Adv 2021; 11:16404-16418. [PMID: 35479155 PMCID: PMC9030808 DOI: 10.1039/d1ra01591e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/20/2021] [Indexed: 11/28/2022] Open
Abstract
The rate constant of the reactions of ˙OH radicals with glyphosate (GPS) and its hydrates (GPS(H2O)n=1–3) were evaluated using the dual method M06-2X/6-311++G(df,p)//6-31+G(df,p) over the temperature range of 200–400 K. The results served to estimate the atmospheric lifetime along with the photochemical ozone creation potential (POCP). The calculations yielded an atmospheric lifetime of 2.34 hours and a POCP of 24.7 for GPS. Upon addition of water molecules, there is an increase of lifetime and decrease of POCP for water monomer and water dimer. The POCP for water trimer is slightly above the gaseous GPS. However, the POCPs of GPS and its hydrates are comparable to that of alkanes. The GPS and its hydrates were found to be a potential reservoir of CO2. The acidification potential (AP) of GPS was found to be 0.189 and decreases upon addition of water molecules. This shows negligible contribution to rain acidification as the AP is less than that of SO2. The UV-vis spectra were attained using the M06-L/6-311++G(3df,3pd) method and cover the range 160–260 nm which fits well with experiment. The rate constant of the reactions of ˙OH radical with glyphosate (GPS) and its hydrates (GPS(H2O)n=1–3) were evaluated using the dual method M06-2X/6-311++G(df,p)//6-31+G(df,p) over the temperature range of 200–400 K.![]()
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Affiliation(s)
- Olivier Holtomo
- Department of Physics
- Faculty of Science
- University of Bamenda
- Cameroon
- Department of Physics
| | | | - Mama Nsangou
- Department of Physics
- Higher Teacher's Training College
- University of Maroua
- Cameroon
- Department of Physics
| | - Ousmanou Motapon
- Department of Physics
- Faculty of Science
- University of Maroua
- Cameroon
- Laboratory of Fundamental Physics
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Baidya B, Lily M, Patgiri D, Hynniewta S, Chandra AK. CHF 2CF 2OCHF 2: conformational analysis and direct dynamics study of its reaction with Cl atoms and atmospheric fate. NEW J CHEM 2020. [DOI: 10.1039/c9nj06069c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Conformers of CHF2CF2OCHF2 are identified, and the kinetics of its reaction with Cl atoms and final atmospheric degradation products are studied to assess atmospheric impact.
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Affiliation(s)
- Bidisha Baidya
- Centre for Advanced Studies in Chemistry
- North – Eastern Hill University
- Shillong
- India
| | - Makroni Lily
- Centre for Advanced Studies in Chemistry
- North – Eastern Hill University
- Shillong
- India
| | - Dimpal Patgiri
- Centre for Advanced Studies in Chemistry
- North – Eastern Hill University
- Shillong
- India
| | - Shemphang Hynniewta
- Centre for Advanced Studies in Chemistry
- North – Eastern Hill University
- Shillong
- India
| | - Asit K. Chandra
- Centre for Advanced Studies in Chemistry
- North – Eastern Hill University
- Shillong
- India
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