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Xu J, Zhang J, Dong Y, Luo Y, Xie W. Effects of polyethylene microplastics on CHCl 3 and CHBr 3 fluxes and microbial community in temperate salt marsh soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 359:124719. [PMID: 39142428 DOI: 10.1016/j.envpol.2024.124719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 08/03/2024] [Accepted: 08/11/2024] [Indexed: 08/16/2024]
Abstract
Microplastics (MPs) affect the carbon cycle in coastal salt marsh soils. However, studies on their effects on CHCl3 and CHBr3, which are volatile halohydrocarbons that can damage the ozone layer, are lacking. In this study, indoor simulation experiments were conducted to explore the effects of MPs invasion on the source and sink characteristics of soil CHCl3 and CHBr3. The results showed that different concentrations of polyethylene (PE)-MPs promoted CHCl3 and CHBr3 emissions. Emission peaks of the two gases appeared on days 3 and 15 during the culture cycle. CHCl3 and CHBr3 fluxes were mainly affected by soil physicochemical properties and microbial communities. PE-MPs caused changes in soil properties, microorganisms, and related functional genes. Soil total organic carbon, which was significantly and positively correlated with CHCl3. Dissolved organic matter, which was one of the main factors affecting CHBr3, its relative content increased after the addition of PE-MPs. The abundances of Methylocella and Dehalococcoides, which mediate dechlorination reduction, decreased with the addition of PE-MPs. The addition of PE-MPs also significantly varied the abundance of ctrA, which controls dechlorination in soil microorganisms. The gene pceA greatly influenced CHCl3 emissions. In addition, CHBr3 flux was influenced by the interactions between sediment redox and microbial co-metabolic reactions under the control of genes such as TC.FEV.OM and soxB. This study provides theoretical and data support for the source and sink characteristics of volatile halohydrocarbons in coastal salt marshes and highlights the environmental hazards of MPs.
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Affiliation(s)
- Jianing Xu
- College of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, China
| | - Jiale Zhang
- College of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, China
| | - Yange Dong
- College of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, China
| | - Yue Luo
- College of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, China
| | - Wenxia Xie
- College of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, China.
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2
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Rais N, Salta Z, Tasinato N. Theoretical investigation of the OH-initiated atmospheric degradation mechanism of CX 2CHX (X = H, F, Cl) by advanced quantum chemical and transition state theory methods. Phys Chem Chem Phys 2024; 26:19976-19991. [PMID: 38995148 DOI: 10.1039/d4cp01453g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
Halogenated olefins are anthropogenic compounds with many industrial applications but at the same time raising many environmental and health concerns. Gas-phase electrophilic addition of the OH radical to the olefinic CC bond represents the primary sink for these chemicals in the atmosphere, with the degree and type of halogenation playing a significant role in their overall reactivity. In this work, we present a theoretical investigation of the reaction mechanisms and kinetics for the reactions between the OH radical and CH2CH2 (ethylene, ETH), CF2CHF (trifluoroethylene, TFE) and CCl2CHCl (trichloroethylene, TCE), simulated by state-of-the-art protocols and methods, with the aim of providing a detailed interpretation of the available experimental results, as well as new data of relevance to tropospheric chemistry. Specifically, potential energy surfaces (PESs) are obtained using the jun-Cheap (jChS) composite scheme, whereas temperature and pressure dependent rate coefficients and product distributions in the 100-600 K temperature range are calculated within the Rice-Ramsperger-Kassel-Marcus/master equation (RRKM/ME) framework. The rates for barrierless channels are obtained from variable reaction coordinate-variational transition state theory (VRC-VTST) combined with the two transition state model. While the reactions with ETH and TFE proceed mainly via the formation of addition adducts at P = 1 atm and T = 298 K, the dominant channel for TCE is the Cl-elimination reaction. Global rate constants for the two halogenated olefins, TFE and TCE, are found to be pressure-independent, contrary to the case of ETH. The computed rate constants, as well as their temperature and pressure dependence, are in remarkable agreement with the available experimental data, and they are used to derive atmospheric lifetimes (τ) for both TFE and TCE as a function of altitude (h) in the atmosphere, by taking into account variations in the rate coefficients (k (T, P)) and [OH] concentration.
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Affiliation(s)
- Nadjib Rais
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa, Italy.
- IUSS Scuola Universitaria Superiore, Piazza della Vittoria 15, I-27100, Pavia, Italy
| | - Zoi Salta
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa, Italy.
| | - Nicola Tasinato
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126, Pisa, Italy.
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3
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Sun Q, Yu X, Wu L, Gao R, Hou Z, Wang Z, Wei L, Jing L, Liu Y, Deng J, Dai H. Boosting Catalytic and Anti-fluorination Performance of the Ru/Vanadia-Titania Catalyst for the Oxidative Destruction of Freon by Sulfuric Acid Modification. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:12719-12730. [PMID: 38959427 DOI: 10.1021/acs.est.4c02864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
Chlorofluorocarbons (CFCs) exert a strong greenhouse effect and constitute the largest contributor to ozone depletion. Catalytic removal is considered an effective pathway for eliminating low-concentration CFCs under mild conditions. The key issue is the easy deactivation of the catalysts due to their surface fluorination. We herein report a comparative investigation on catalytic dichlorodifluoromethane (CFC-12) removal in the absence or presence of water over the sulfuric-acid-modified three-dimensionally ordered macroporous vanadia-titania-supported Ru (S-Ru/3DOM VTO) catalysts. The S-Ru/3DOM VTO catalyst exhibited high activity (T90% = 278 °C at space velocity = 40 000 mL g-1 h-1) and good stability within 60 h of on-stream reaction in the presence of 1800 ppm of water due to the improvements in acid site amount and redox ability that promoted the adsorption of CFC-12 and the activation of C-F bonds. Compared with the case under dry conditions, catalytic performance for CFC-12 removal was better over the S-Ru/3DOM VTO catalyst in the presence of water. Water introduction mitigated surface fluorination by the replenishment of hydroxyl groups, inhibited the formation of halogenated byproducts via the surface fluorine species cleaning effect, and promoted the reaction pathway of COX2 (X = Cl/F) → carboxylic acid → CO2.
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Affiliation(s)
- Qinpei Sun
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Xiaohui Yu
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Linke Wu
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Ruyi Gao
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Zhiquan Hou
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Zhiwei Wang
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Lu Wei
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Lin Jing
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Yuxi Liu
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Jiguang Deng
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
| | - Hongxing Dai
- Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Department of Chemical Engineering and Technology, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China
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4
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Yu W, Gong F, Xu H, Zhou X. Molecular Mechanism of Exogenous ABA to Enhance UV-B Resistance in Rhododendron chrysanthum Pall. by Modulating Flavonoid Accumulation. Int J Mol Sci 2024; 25:5248. [PMID: 38791294 PMCID: PMC11121613 DOI: 10.3390/ijms25105248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/08/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024] Open
Abstract
With the depletion of the ozone layer, the intensity of ultraviolet B (UV-B) radiation reaching the Earth's surface increases, which in turn causes significant stress to plants and affects all aspects of plant growth and development. The aim of this study was to investigate the mechanism of response to UV-B radiation in the endemic species of Rhododendron chrysanthum Pall. (R. chrysanthum) in the Changbai Mountains and to study how exogenous ABA regulates the response of R. chrysanthum to UV-B stress. The results of chlorophyll fluorescence images and OJIP kinetic curves showed that UV-B radiation damaged the PSII photosystem of R. chrysanthum, and exogenous ABA could alleviate this damage to some extent. A total of 2148 metabolites were detected by metabolomics, of which flavonoids accounted for the highest number (487, or 22.67%). KEGG enrichment analysis of flavonoids that showed differential accumulation by UV-B radiation and exogenous ABA revealed that flavonoid biosynthesis and flavone and flavonol biosynthesis were significantly altered. GO analysis showed that most of the DEGs produced after UV-B radiation and exogenous ABA were distributed in the cellular process, cellular anatomical entity, and catalytic activity. Network analysis of key DFs and DEGs associated with flavonoid synthesis identified key flavonoids (isorhamnetin-3-O-gallate and dihydromyricetin) and genes (TRINITY_DN2213_c0_g1_i4-A1) that promote the resistance of R. chrysanthum to UV-B stress. In addition, multiple transcription factor families were found to be involved in the regulation of the flavonoid synthesis pathway under UV-B stress. Overall, R. chrysanthum actively responded to UV-B stress by regulating changes in flavonoids, especially flavones and flavonols, while exogenous ABA further enhanced its resistance to UV-B stress. The experimental results not only provide a new perspective for understanding the molecular mechanism of the response to UV-B stress in the R. chrysanthum, but also provide a valuable theoretical basis for future research and application in improving plant adversity tolerance.
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Affiliation(s)
| | | | - Hongwei Xu
- Jilin Provincial Key Laboratory of Plant Resource Science and Green Production, Jilin Normal University, Siping 136000, China
| | - Xiaofu Zhou
- Jilin Provincial Key Laboratory of Plant Resource Science and Green Production, Jilin Normal University, Siping 136000, China
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5
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Kakati UP, Dowerah D, Deka RC, Gour NK, Paul S. Oxidation pathways and kinetics of the 1,1,2,3-tetrafluoropropene (CF 2CF-CH 2F) reaction with Cl-atoms and subsequent aerial degradation of its product radicals in the presence of NO. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:734-750. [PMID: 38426396 DOI: 10.1039/d3em00545c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
To give a comprehensive account of the environmental acceptability of 1,1,2,3-tetrafluoropropene (CF2CF-CH2F) in the troposphere, we have examined the oxidation reaction pathways and kinetics of CF2CF-CH2F initiated by Cl-atoms using the second-order Møller-Plesset perturbation (MP2) theory along with the 6-31+G(d,p) basis set. We also performed single-point energy calculations to further refine the energies at the CCSD(T) level along with the basis sets 6-31+G(d,p) and 6-311++G(d,p). The estimation of the relative energies and thermodynamic parameters of the CF2CF-CH2F + Cl reaction clearly shows that Cl-atom addition reaction pathways are more dominant compared to H-abstraction reaction pathways. The value of the rate coefficient for each reaction channel is calculated using the conventional transition state theory (TST) over the temperature range of 200-1000 K at 1 atm. The estimated overall rate coefficients for the title reaction are found to be 1.10 × 10-12, 1.21 × 10-10, and 1.13 × 10-8 cm3 per molecule per s via the respective calculation methods viz. MP2/6-31+G(d,p), CCSD(T)//MP2/6-31+G(d,p), and CCSD(T)/6-311++G(d,p)//MP2/6-31+G(d,p), at 298.15 K. Moreover, the calculated rate coefficients and percentage branching ratio values suggest that the Cl-atom addition reaction at the β-carbon atom is more preferable to that of the α-carbon addition to CF2CF-CH2F. Based on the rate coefficient values calculated by the three different methods, the atmospheric lifetime for the title reaction at 298.15 K is estimated. The radiative efficiency (RE) and Global Warming Potential (GWP) results of the title molecule show that its GWP would be negligible. Further, we have explored the degradation of its product radicals in the presence of O2 and NO. From the degradation results, we have found that CF2(Cl)COF, FCOCH2F, FCFO and FCOCl are formed as stable end products along with various radicals such as ˙CF2Cl and ˙CH2F. Therefore, these findings of kinetic and mechanistic data can be applied to the development and implementation of a novel CFC replacement.
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Affiliation(s)
| | - Dikshita Dowerah
- Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India.
| | - Ramesh Chandra Deka
- Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India.
| | - Nand Kishor Gour
- Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam, India.
| | - Subrata Paul
- Department of Chemistry, Assam University, Silchar-788011, Assam, India
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6
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Yu Y, Pan L, Sun Q, Wang J. The mechanism and kinetics of the atmospheric oxidation of CF 3(CF 2) 2CHCH 2 (HFC-1447fz) by hydroxyl radicals: ab initio investigation. Phys Chem Chem Phys 2024; 26:10989-10997. [PMID: 38526437 DOI: 10.1039/d3cp06149c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
The oxidation of 3,3,4,4,5,5,5-heptafluoro-1-pentene (HFC-1447fz) by hydroxyl radicals plays a crucial role in atmospheric conditions. By employing the CCSD(T)/cc-pVTZ//M06-2X/6-311++G(d,p) level of theory, the detailed reaction mechanism, kinetics and atmospheric implications of the degradation of HFC-1447fz by hydroxyl radicals were investigated. Compared to H-abstraction channels, the OH addition reaction is determined to be more favorable initial pathways in the degradation processes of HFC-1447fz. The overall rate coefficient of the degradation of HFC-1447fz by OH radicals is estimated to be 1.66 × 10-12 cm3 molecule-1 s-1 and the lifetime of HFC-1447fz is found to be 7 days at 298 K, which are in good agreement with the reported experimental results. The global warming potential (GWP) for HFC-1447fz on the 50, 100 and 500-year time horizons is estimated using the calculated rate coefficient. Furthermore, the mechanisms of the subsequent reactions of two OH-addition adducts have also been investigated. By TD-DFT calculations, it was found that eleven species can undergo photodissociation, while ten other species are photolytically stable under sunlight.
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Affiliation(s)
- Youqing Yu
- Green Intelligence Environmental School, Yangtze Normal University, Chongqing 408100, China.
| | - Li Pan
- Chongqing Medical and Health School, Chongqing 408100, China
| | - Qiyao Sun
- Green Intelligence Environmental School, Yangtze Normal University, Chongqing 408100, China.
| | - Jie Wang
- Green Intelligence Environmental School, Yangtze Normal University, Chongqing 408100, China.
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7
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Beck IT, Lahm ME, Douberly GE, Schaefer HF. Convergent ab initio analysis of the multi-channel HOBr + H reaction. J Chem Phys 2024; 160:124304. [PMID: 38516979 DOI: 10.1063/5.0200276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 03/06/2024] [Indexed: 03/23/2024] Open
Abstract
High-level potential energy surfaces for three reactions of hypobromous acid with atomic hydrogen were computed at the CCSDTQ/CBS//CCSDT(Q)/complete basis set level of theory. Focal point analysis was utilized to extrapolate energies and gradients for energetics and optimizations, respectively. The H attack at Br and subsequent Br-O cleavage were found to proceed barrierlessly. The slightly submerged transition state lies -0.2 kcal mol-1 lower in energy than the reactants and produces OH and HBr. The two other studied reaction paths are the radical substitution to produce H2O and Br with a 4.0 kcal mol-1 barrier and the abstraction at hydrogen to produce BrO and H2 with an 11.2 kcal mol-1 barrier. The final product energies lie -37.2, -67.9, and -7.3 kcal mol-1 lower in energy than reactants, HOBr + H, for the sets of products OH + HBr, H2O + Br, and H2 + BrO, respectively. Additive corrections computed for the final energetics, particularly the zero-point vibrational energies and spin-orbit corrections, significantly impacted the final stationary point energies, with corrections up to 6.2 kcal mol-1.
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Affiliation(s)
- Ian T Beck
- Department of Chemistry and Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Mitchell E Lahm
- Department of Chemistry and Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Gary E Douberly
- Department of Chemistry and Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Henry F Schaefer
- Department of Chemistry and Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, USA
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8
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Shea JE, Crawford TD, Kirchner B, Hartland GV, Aumiller W. 50 and 100 Years Ago in The Journal of Physical Chemistry─2024 Edition. J Phys Chem A 2024; 128:1551-1554. [PMID: 38449433 DOI: 10.1021/acs.jpca.4c00715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Affiliation(s)
- Joan-Emma Shea
- Department of Chemistry and Biochemistry and Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - T Daniel Crawford
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Molecular Sciences Software Institute, Blacksburg, Virginia 24060, United States
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, D-53115 Bonn, Germany
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - William Aumiller
- American Chemical Society, 1155 Sixteenth Street N.W., Washington, DC 20036, United States
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Shea JE, Crawford TD, Kirchner B, Hartland GV, Aumiller W. 50 and 100 Years Ago in The Journal of Physical Chemistry─2024 Edition. J Phys Chem B 2024; 128:2053-2056. [PMID: 38449439 DOI: 10.1021/acs.jpcb.4c00716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Affiliation(s)
- Joan-Emma Shea
- Department of Chemistry and Biochemistry and Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - T Daniel Crawford
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Molecular Sciences Software Institute, Blacksburg, Virginia 24060, United States
| | - Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Clausius Institute of Physical and Theoretical Chemistry, University of Bonn, D-53115 Bonn, Germany
| | - Gregory V Hartland
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - William Aumiller
- American Chemical Society, 1155 Sixteenth Street N.W., Washington, DC 20036, United States
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Zheng Z, Mao J, Tan X, Jia L, Liu T. Catalytic hydrolysis of monochlorodifluoromethane over ZnO/ZrO 2 catalysts at low temperatures. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:19348-19362. [PMID: 38358630 DOI: 10.1007/s11356-024-32265-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 01/26/2024] [Indexed: 02/16/2024]
Abstract
Monochlorodifluoromethane (HCFC-22) has been identified as a significant contributor to the depletion of the Earth's ozone layer, garnering considerable attention within the scientific community. Consequently, the investigation of Freon degradation has become a central focus of current research efforts. In this study, we opted to employ catalytic hydrolysis as it offers numerous advantages for the degradation of HCFC-22. Specifically, we prepared ZnO/ZrO2 catalysts with hexahedral rod-like structures through citric acid complexation. We examined the impact of various preparation conditions (such as the molar ratio of ZnO to ZrO2, calcination temperature, and calcination time) as well as catalytic hydrolysis conditions (including the amount of catalyst, total flow rate, and catalytic hydrolysis temperature) on the hydrolysis rate of HCFC-22. Characterization of the catalysts was performed using techniques such as XRD, SEM, EDS, TG-DTG, FTIR, N2 adsorption-desorption, CO2-TPD, and NH3-TPD. Our experimental findings revealed the optimal preparation conditions: a catalytic hydrolysis temperature of 100 °C, a molar ratio of ZnO to ZrO2 of 0.7, a water bath temperature of 90 °C, a roasting temperature of 400 °C, and a roasting time of 4 h. At a catalytic hydrolysis temperature of 100 °C, the hydrolysis rate of HCFC-22 reached 99.81%, with the main hydrolyzed products being HCl, HF, and CO2.
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Affiliation(s)
- Zhen Zheng
- College of Chemistry and Environment, Yunnan Minzu University, National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Kunming, 650504, Yunnan, China
| | - Junhao Mao
- College of Chemistry and Environment, Yunnan Minzu University, National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Kunming, 650504, Yunnan, China
| | - Xiaofang Tan
- College of Chemistry and Environment, Yunnan Minzu University, National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Kunming, 650504, Yunnan, China
| | - Lijuan Jia
- College of Chemistry and Environment, Yunnan Minzu University, National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Kunming, 650504, Yunnan, China
| | - Tiancheng Liu
- College of Chemistry and Environment, Yunnan Minzu University, National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Kunming, 650504, Yunnan, China.
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11
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Seo J, Ukani R, Zheng J, Braun JD, Wang S, Chen FE, Kim HK, Zhang S, Thai C, McGillicuddy RD, Yan H, Vlassak JJ, Mason JA. Barocaloric Effects in Dialkylammonium Halide Salts. J Am Chem Soc 2024; 146:2736-2747. [PMID: 38227768 DOI: 10.1021/jacs.3c12402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Barocaloric effects─solid-state thermal changes induced by the application and removal of hydrostatic pressure─offer the potential for energy-efficient heating and cooling without relying on volatile refrigerants. Here, we report that dialkylammonium halides─organic salts featuring bilayers of alkyl chains templated through hydrogen bonds to halide anions─display large, reversible, and tunable barocaloric effects near ambient temperature. The conformational flexibility and soft nature of the weakly confined hydrocarbons give rise to order-disorder phase transitions in the solid state that are associated with substantial entropy changes (>200 J kg-1 K-1) and high sensitivity to pressure (>24 K kbar-1), the combination of which drives strong barocaloric effects at relatively low pressures. Through high-pressure calorimetry, X-ray diffraction, and Raman spectroscopy, we investigate the structural factors that influence pressure-induced phase transitions of select dialkylammonium halides and evaluate the magnitude and reversibility of their barocaloric effects. Furthermore, we characterize the cyclability of thin-film samples under aggressive conditions (heating rate of 3500 K s-1 and over 11,000 cycles) using nanocalorimetry. Taken together, these results establish dialkylammonium halides as a promising class of pressure-responsive thermal materials.
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Affiliation(s)
- Jinyoung Seo
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Rahil Ukani
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Juanjuan Zheng
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Jason D Braun
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Sicheng Wang
- Department of Chemistry, University of North Texas, Denton, Texas 76203, United States
| | - Faith E Chen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Hong Ki Kim
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Selena Zhang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Catherine Thai
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Ryan D McGillicuddy
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Hao Yan
- Department of Chemistry, University of North Texas, Denton, Texas 76203, United States
| | - Joost J Vlassak
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Jarad A Mason
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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12
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Snell N. Medicinal Products and Environmental Pollution. Pharmaceut Med 2024; 38:5-7. [PMID: 37904074 DOI: 10.1007/s40290-023-00502-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2023] [Indexed: 11/01/2023]
Affiliation(s)
- Noel Snell
- National Heart and Lung Institute, Imperial College London, London, UK.
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13
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Moradkhani M, Naghipour A, Tyula YA. Ab initio investigation of the competition of pnicogen, halogen, and hydrogen bonds resulting from the interactions between cyanophosphine and hypohalous acids. J Mol Model 2023; 30:15. [PMID: 38153592 DOI: 10.1007/s00894-023-05809-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/11/2023] [Indexed: 12/29/2023]
Abstract
CONTEXT The complexes formed as a result of the interactions between cyanophosphine (CP, H2PCN) and hypohalous acid molecules (HOX, X = F, Cl, Br, and I) were studied by employing ab initio computations conducted at the MP2/aug-cc-pVTZ level. Three types of complexes were acquired (I, II, and III) as a result of the (O∙∙∙P) pnicogen bond, the (N∙∙∙H) hydrogen bond, and the (N∙∙∙X) halogen bond interaction, respectively. The results of harmonic vibrational frequency calculations with no imaginary frequencies confirmed the structures as minima. In addition, given the interaction energy of the complexes, hydrogen bond complexes of structure II have the highest stability compared to other structures. In all studied complexes, the strength of the interactions depended on the electronegativity of the halogen atoms. The characteristics and nature of the whole three types of complexes were examined and evaluated with natural bond orbital (NBO), atom in molecules (AIM), molecular electrostatic potential (MEP) maps, non-covalent interaction (NCI) index, and electron density difference (EDD) analyses. METHOD The optimization of all complexes and corresponding monomers was conducted through the ab initio method, employing the MP2 level along with the aug/cc-pVTZ basis set for all atoms, except for the iodine (I) atom, for which the aug-cc-pVTZ (PP) basis set was employed. Subsequent frequency calculations were executed to ascertain the minimum energy state of the complexes at the MP2 level and the aug/cc-pVTZ basis set, utilizing Gaussian09 software. The MEP maps of the monomers were generated using the analysis-surface suite (WFA-SAS) software package. To probe the orbital interactions within the studied complexes, NBO analysis was performed employing NBO software. The assessment of bond nature, topological features, and electron density values at critical points for the studied complexes was undertaken using AIMAll software. The NCI index was derived utilizing Multiwfn software, and its three-dimensional representation was rendered using VMD software.
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Affiliation(s)
| | - Ali Naghipour
- Department of Chemistry, Faculty of Science, Ilam University, Ilam, 69315-516, Iran.
| | - Yunes Abbasi Tyula
- Department of Chemistry, Faculty of Science, Ilam University, Ilam, 69315-516, Iran.
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14
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McGillen MR, Fried ZTP, Khan MAH, Kuwata KT, Martin CM, O’Doherty S, Pecere F, Shallcross DE, Stanley KM, Zhang K. Ozonolysis can produce long-lived greenhouse gases from commercial refrigerants. Proc Natl Acad Sci U S A 2023; 120:e2312714120. [PMID: 38079548 PMCID: PMC10742373 DOI: 10.1073/pnas.2312714120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 10/30/2023] [Indexed: 12/24/2023] Open
Abstract
Hydrofluoroolefins are being adopted as sustainable alternatives to long-lived fluorine- and chlorine-containing gases and are finding current or potential mass-market applications as refrigerants, among a myriad of other uses. Their olefinic bond affords relatively rapid reaction with hydroxyl radicals present in the atmosphere, leading to short lifetimes and proportionally small global warming potentials. However, this type of functionality also allows reaction with ozone, and whilst these reactions are slow, we show that the products of these reactions can be extremely long-lived. Our chamber measurements show that several industrially important hydrofluoroolefins produce CHF3 (fluoroform, HFC-23), a potent, long-lived greenhouse gas. When this process is accounted for in atmospheric chemical and transport modeling simulations, we find that the total radiative effect of certain compounds can be several times that of the direct radiative effect currently recommended by the World Meteorological Organization. Our supporting quantum chemical calculations indicate that a large range of exothermicity is exhibited in the initial stages of ozonolysis, which has a powerful influence on the CHF3 yield. Furthermore, we identify certain molecular configurations that preclude the formation of long-lived greenhouse gases. This demonstrates the importance of product quantification and ozonolysis kinetics in determining the overall environmental impact of hydrofluoroolefin emissions.
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Affiliation(s)
- Max R. McGillen
- CNRS-Orléans, Institut de Combustion Aérothermique Réactivité et Environnement, Orléans45071, France
| | - Zachary T. P. Fried
- Department of Chemistry, Massachusetts Institute of Technology, Boston, MA02139
| | - M. Anwar H. Khan
- School of Chemistry, University of Bristol, BristolBS8 1TS, United Kingdom
| | - Keith T. Kuwata
- Department of Chemistry, Macalester College, Saint Paul, MN55105
| | - Connor M. Martin
- Department of Chemistry, University of California, Irvine, CA92697
| | - Simon O’Doherty
- School of Chemistry, University of Bristol, BristolBS8 1TS, United Kingdom
| | - Francesco Pecere
- Department of Chemistry, The Pennsylvania State University, State College, PA16801
| | | | - Kieran M. Stanley
- School of Chemistry, University of Bristol, BristolBS8 1TS, United Kingdom
| | - Kexin Zhang
- Department of Chemistry, Northwestern University, Evanston, IL60208
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15
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Anand VJ, Kumar P. Mechanistic insight into the N 2O + O( 1D, 3P) reaction: role of post-CCSD(T) corrections and non-adiabatic effects. Phys Chem Chem Phys 2023. [PMID: 38044865 DOI: 10.1039/d3cp03830k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
In the present work, we have studied the N2O + O(1D,3P) reaction using high level quantum chemical calculations along with non-adiabatic kinetics. For quantum chemical calculations, we used the post-CCSD(T) method, which includes corrections from full triple excitations and partial quadratic excitations at the coupled-cluster level. For both the paths (N2 + O2 and 2NO), we have computed the rate constants over a wide range of temperatures (100-500 K for singlet paths and 700-4000 K for triplet paths). To assess the accuracy of our computations, we have compared our results with various experimentally measured quantities (absolute rate constant, branching fraction, and crossover temperature) and found a good match with all of them. We recommend the Arrhenius expressions for singlet paths, which turn out to be 4.46 × 10-11 exp(0.022/RT) cm3 molecule-1 s-1 and 7.12 × 10-11 exp(0.024/RT) cm3 molecule-1 s-1 for N2 + O2 and NO paths, respectively. For triplet paths, our recommended Arrhenius expressions are 5.15 × 10-12 exp(-15.35/RT) cm3 molecule-1 s-1 and 1.59 × 10-10 exp(-27.76/RT) cm3 molecule-1 s-1 for N2 + O2 and NO paths, respectively.
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Affiliation(s)
- Vishva Jeet Anand
- Department of Chemistry, Malaviya National Institute of Technology Jaipur, Jaipur, 302017, India.
| | - Pradeep Kumar
- Department of Chemistry, Malaviya National Institute of Technology Jaipur, Jaipur, 302017, India.
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16
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Chokbunpiam T, Fritzsche S, Ploymeerusmee T, Chanajaree R, Thompho S, Janke W, Hannongbua S. Separation of the Chlorofluorocarbon (CFC) CCl 2F 2 from N 2 in NaY Zeolite, in MIL-127(Fe) and in the two Carbon Nanotubes CNT (9,9) and CNT (11,11). J Mol Graph Model 2023; 125:108597. [PMID: 37625172 DOI: 10.1016/j.jmgm.2023.108597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/06/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023]
Abstract
Four well-suited porous materials for the selective adsorption of the most prominent CFC, which is CCl2F2, from the air are carbon nanotubes CNT (9,9) and CNT (11,11), NaY zeolite, and the Metal Organic Framework MIL-125(Fe). The adsorption has been investigated through molecular simulations. Simulation results and theoretical considerations show that reasons for the extraordinarily high selectivity in all four cases were found to be the differences in the enthalpy of adsorption for the various adsorbed gases rather than steric reasons. The four adsorbate-adsorbent systems have been examined at different temperatures, pressures, and concentration ratios in the mixture. Among them, the carbon nanotube CNT (11,11) exhibited the highest selectivity, reaching up to 104.
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Affiliation(s)
- Tatiya Chokbunpiam
- Department of Chemistry, Faculty of Science, Ramkhamhaeng University, 10240, Bangkok, Thailand.
| | - Siegfried Fritzsche
- University of Leipzig, Faculty of Physics and Geosciences, Institute for Theoretical Physics, IPF 231101, 04081, Leipzig, Germany
| | - Tanawut Ploymeerusmee
- Computational Chemistry Unit Cell (CCUC), Department of Chemistry, Faculty of science, Chulalongkorn University, 10330, Bangkok, Thailand
| | - Rungroj Chanajaree
- Chulalongkorn University, Metallurgy and Materials Science Research Institute (MMRI), 10330, Bangkok, Thailand
| | - Somphob Thompho
- Pharmaceutical Research Instrument Center, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Pathum Wan, 10330, Bangkok, Thailand
| | - Wolfhard Janke
- University of Leipzig, Faculty of Physics and Geosciences, Institute for Theoretical Physics, IPF 231101, 04081, Leipzig, Germany
| | - Supot Hannongbua
- Computational Chemistry Unit Cell (CCUC), Department of Chemistry, Faculty of science, Chulalongkorn University, 10330, Bangkok, Thailand
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17
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Jin P. Vertebrates under ultraviolet radiation. GLOBAL CHANGE BIOLOGY 2023; 29:6437-6438. [PMID: 37439296 DOI: 10.1111/gcb.16878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 07/03/2023] [Indexed: 07/14/2023]
Affiliation(s)
- Peng Jin
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, China
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18
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Gamit HA, Amaresan N. Methylobacterium spp. mitigation of UV stress in mung bean (Vigna radiata L.). Photochem Photobiol Sci 2023; 22:2839-2850. [PMID: 37838625 DOI: 10.1007/s43630-023-00490-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 09/29/2023] [Indexed: 10/16/2023]
Abstract
Methylotrophs are a diverse group of bacteria that abundantly colonize the phyllosphere and have great potential to withstand UV irradiation because of their pigmented nature and ability to promote plant growth through various mechanisms. The present study investigated the effects of UVB radiation on plant growth-promoting (PGP) properties of methylotrophic bacteria and the growth of Vigna radiata L. A total of 55 methylotrophic bacteria were isolated from desert plants, and 15 methylotrophs were resistant to UVB radiation for 4 h. All UVB-resistant methylotrophs possess a methyldehydrogenase gene. Identification based on 16S rRNA gene sequencing revealed that all 15 UVB-resistant methylotrophs belonged to the genera Methylorubrum (07), Methylobacterium (07), and Rhodococcus (01). Screening of methylotrophs for PGP activity in the presence and absence of UVB radiation revealed that all isolates showed ACC deaminase activity and growth on a nitrogen-free medium. Furthermore, the production of IAA-like substances ranged from 8.62 to 85.76 µg/mL, siderophore production increased from 3.47 to 65.75% compared to the control. Seed germination assay with V. radiata L. (mung bean) exposed to UVB radiation revealed that methylotrophs improved seed germination, root length, and shoot length compared to the control. The present findings revealed that the isolates SD3, SD2, KD1, KD5, UK1, and UK3 reduced the deleterious effects of UVB radiation on mung bean plants and can be used to protect seedlings from UVB radiation for sustainable agriculture.
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Affiliation(s)
- Harshida A Gamit
- C. G. Bhakta Institute of Biotechnology, Uka Tarsadia University, Maliba Campus, Bardoli, Surat, 394 350, Gujarat, India
| | - Natarajan Amaresan
- C. G. Bhakta Institute of Biotechnology, Uka Tarsadia University, Maliba Campus, Bardoli, Surat, 394 350, Gujarat, India.
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19
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Petersen AC, Sølling TI. Dissociation processes of ionized freons: CHFCl2+ and CF2Cl2+ in the gas phase. J Chem Phys 2023; 159:174306. [PMID: 37921250 DOI: 10.1063/5.0169883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 10/13/2023] [Indexed: 11/04/2023] Open
Abstract
The present study reveals the effects of symmetry on how the distribution and flow of energy play out on the decomposition of small halocarbons. Unimolecular decay of the freons CHFCl2 and CF2Cl2 when ionized has been investigated. Mass spectrometric results that encompass isotope effects (peak heights) and energy distribution in the exit channel (peak shapes) are interpreted by computational methods. Non-statistical processes of electronic predissociation and isolated state decay are shown to be directly associated with molecular symmetry.
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Affiliation(s)
- Allan Christian Petersen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen, DK 2100, Denmark
| | - Theis Ivan Sølling
- Center for Integrative Petroleum Research, College of Petroleum and Geosciences, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
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20
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Hader JD, Fairén AG, MacLeod M. Planetary Protection requirements should address pollution from chemicals and materials. Proc Natl Acad Sci U S A 2023; 120:e2310792120. [PMID: 37819976 PMCID: PMC10589715 DOI: 10.1073/pnas.2310792120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023] Open
Affiliation(s)
- John D. Hader
- Department of Environmental Science, Stockholm University, Stockholm10691, Sweden
| | - Alberto G. Fairén
- Centro de Astrobiología, Consejo Superior de Investigaciones Científicas-Instituto Nacional de Técnica Aeroespacial, Torrejón de Ardoz, Madrid28850, Spain
- Department of Astronomy, Cornell University, Ithaca, NY14853
| | - Matthew MacLeod
- Department of Environmental Science, Stockholm University, Stockholm10691, Sweden
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21
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Nielsen OJ, Sulbaek Andersen MP. Hydrofluorocarbons, Climate, and Health. N Engl J Med 2023; 389:1059. [PMID: 37703571 DOI: 10.1056/nejmc2308778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
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22
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Muellers TD, Petrovic PV, Zimmerman JB, Anastas PT. Toward Property-Based Regulation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:11718-11730. [PMID: 37527361 DOI: 10.1021/acs.est.3c00643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
An expanding web of adverse impacts on people and the environment has been steadily linked to anthropogenic chemicals and their proliferation. Central to this web are the regulatory structures intended to protect human and environmental health through the control of new molecules. Through chronically insufficient and inefficient action, the current chemical-by-chemical regulatory approach, which considers regulation at the level of chemical identity, has enabled many adverse impacts to develop and persist. Recognizing the link between fundamental physicochemical properties and hazards, we describe a new paradigm─property-based regulation. By regulating physicochemical properties, we show how governments can delineate and enforce safe chemical spaces, increasing the scalability of chemical assessments, reducing the time and resources to regulate a substance, and providing transparency for chemical designers. We highlight sparse existing property-based approaches and demonstrate their applicability using bioaccumulation as an example. Finally, we present a path to implementation in the United States, prescribing roles and steps for government, nongovernmental organizations, and industry to accelerate this transition, to the benefit of all.
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Affiliation(s)
- Tobias D Muellers
- School of the Environment, Yale University, 195 Prospect St, New Haven, Connecticut 06511, United States
- Center for Green Chemistry and Green Engineering, Yale University, 370 Prospect St, New Haven, Connecticut 06511, United States
| | - Predrag V Petrovic
- School of the Environment, Yale University, 195 Prospect St, New Haven, Connecticut 06511, United States
- Center for Green Chemistry and Green Engineering, Yale University, 370 Prospect St, New Haven, Connecticut 06511, United States
| | - Julie B Zimmerman
- School of the Environment, Yale University, 195 Prospect St, New Haven, Connecticut 06511, United States
- Center for Green Chemistry and Green Engineering, Yale University, 370 Prospect St, New Haven, Connecticut 06511, United States
| | - Paul T Anastas
- School of the Environment, Yale University, 195 Prospect St, New Haven, Connecticut 06511, United States
- Center for Green Chemistry and Green Engineering, Yale University, 370 Prospect St, New Haven, Connecticut 06511, United States
- School of Public Health, Yale University, 60 College St, New Haven, Connecticut 06520, United States
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23
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Ulenikov O, Bekhtereva E, Gromova O, Fomchenko A, Morzhikova Y, Sidko S, Sydow C, Bauerecker S. Effective Dipole Moment Model for Axially Symmetric C3v Molecules: Application to the Precise Study of Absolute Line Strengths of the ν6 Fundamental of CH 335Cl. Int J Mol Sci 2023; 24:12122. [PMID: 37569499 PMCID: PMC10418978 DOI: 10.3390/ijms241512122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 07/21/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
The effective dipole moment model for molecules of axial C3v symmetry is derived on the basis of the symmetry properties of a molecule which, on the one hand, is of the same order of efficiency (but much simpler and clearer in applications) as the analogous models derived on the basis of the irreducible tensorial sets theory, and, on the other hand, mathematically more correct in comparison with concepts like the Herman-Walles function used in the models. As an application of the general results obtained, we discuss high-resolution infrared spectra of CH335Cl, recorded with the Zürich prototype ZP2001 (Bruker IFS125 HR) Fourier transform infrared spectrometer at a resolution of 0.001 cm-1 and analyzed in the region of 880-1190 cm-1 (ν6 bending fundamental centered at ν0 = 1018.070790 cm-1). Absolute strengths of more than 2800 transitions (2081 lines) were obtained from the fit of their shapes both with Voigt and Hartmann-Tran profiles, and parameters of the effective dipole moment of the ν6 band were determined by the computer code SYMTOMLIST (SYMmetric TOp Molecules: LIne STrengths), created on the basis of a derived theoretical model. As the first step of the analysis of the experimental data, assignments of the recorded lines were made. A total of 5124 transitions with Jmax = 68, Kmax = 21 were assigned to the ν6 band. The weighted fit of 2077 upper energy values obtained from the experimentally recorded transitions was made with a Hamiltonian which takes into account different types of ro-vibrational effects in doubly degenerate vibrational states of the C3v-symmetric molecule. As the result, a set of 25 fitted parameters was obtained which reproduces the initial 2077 upper "experimental" ro-vibrational energy values with a root mean square deviation drms=4.7×10-5 cm-1. At the second step of the analysis, the computer code SYMTOMLIST was used for determination of the parameters of the derived effective dipole moment model. Six effective dipole moment parameters were obtained from the weighted fit procedure which reproduces absolute experimental strengths of the 2804 initial experimental transitions with a relative drms=3.4%.
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Affiliation(s)
- Oleg Ulenikov
- Research School of High-Energy Physics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia; (E.B.); (O.G.); (A.F.); (Y.M.); (S.S.)
| | - Elena Bekhtereva
- Research School of High-Energy Physics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia; (E.B.); (O.G.); (A.F.); (Y.M.); (S.S.)
| | - Olga Gromova
- Research School of High-Energy Physics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia; (E.B.); (O.G.); (A.F.); (Y.M.); (S.S.)
| | - Anna Fomchenko
- Research School of High-Energy Physics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia; (E.B.); (O.G.); (A.F.); (Y.M.); (S.S.)
| | - Yulia Morzhikova
- Research School of High-Energy Physics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia; (E.B.); (O.G.); (A.F.); (Y.M.); (S.S.)
| | - Sergei Sidko
- Research School of High-Energy Physics, National Research Tomsk Polytechnic University, 634050 Tomsk, Russia; (E.B.); (O.G.); (A.F.); (Y.M.); (S.S.)
| | - Christian Sydow
- Institut für Physikalische und Theoretische Chemie, Technische Universität Braunschweig, D-38106 Braunschweig, Germany; (C.S.); (S.B.)
| | - Sigurd Bauerecker
- Institut für Physikalische und Theoretische Chemie, Technische Universität Braunschweig, D-38106 Braunschweig, Germany; (C.S.); (S.B.)
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24
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Schio L, Alagia M, Richter R, Zhaunerchyk V, Stranges S, Pirani F, Vecchiocattivi F, Parriani M, Falcinelli S. Double Photoionization of Nitrosyl Chloride by Synchrotron Radiation in the 24-70 eV Photon Energy Range. Molecules 2023; 28:5218. [PMID: 37446880 DOI: 10.3390/molecules28135218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 06/15/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
The behavior of nitrosyl chloride (ClNO) exposed to ionizing radiation was studied by direct probing valence-shell electrons in temporal coincidence with ions originating from the fragmentation process of the transient ClNO2+. Such a molecular dication was produced by double photoionization with synchrotron radiation in the 24-70 eV photon energy range. The experiment has been conducted at the Elettra Synchrotron Facility of Basovizza (Trieste, Italy) using a light beam linearly polarized with the direction of the polarization vector parallel to the ClNO molecular beam axis. ClNO molecules crossing the photon beam at right angles in the scattering region are generated by effusive expansion and randomly oriented. The threshold energy for the double ionization of ClNO (30.1 ± 0.1 eV) and six dissociation channels producing NO+/Cl+, N+/Cl+, N+/O+, O+/Cl+, ClN+/O+, NO+/Cl2+ ion pairs, with their relative abundance and threshold energies, have been measured.
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Affiliation(s)
- Luca Schio
- IOM CNR Laboratorio TASC, 34012 Trieste, Italy
| | | | - Robert Richter
- Sincrotrone Trieste, Area Science Park, 34149 Trieste, Italy
| | - Vitali Zhaunerchyk
- Department of Physics, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - Stefano Stranges
- IOM CNR Laboratorio TASC, 34012 Trieste, Italy
- Department of Chemistry and Drug Technology, University of Rome Sapienza, 00185 Rome, Italy
| | - Fernando Pirani
- Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
| | - Franco Vecchiocattivi
- Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy
| | - Marco Parriani
- Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy
| | - Stefano Falcinelli
- Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy
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25
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Muir DCG, Getzinger GJ, McBride M, Ferguson PL. How Many Chemicals in Commerce Have Been Analyzed in Environmental Media? A 50 Year Bibliometric Analysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37319372 DOI: 10.1021/acs.est.2c09353] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Over the past 50 years, there has been a tremendous expansion in the measurement of chemical contaminants in environmental media. But how many chemicals have actually been determined, and do they represent a significant fraction of substances in commerce or of chemicals of concern? To address these questions, we conducted a bibliometric survey to identify what individual chemicals have been determined in environmental media and their trends over the past 50 years. The CAplus database of CAS, a Division of the American Chemical Society, was searched for indexing roles "analytical study" and "pollutant" yielding a final list of 19,776 CAS Registry Numbers (CASRNs). That list was then used to link the CASRNs to biological studies, yielding a data set of 9.251 × 106 total counts of the CASRNs over a 55 year period. About 14,150 CASRNs were substances on various priority lists or their close analogs and transformation products. The top 100 most reported CASRNs accounted for 34% of the data set, confirming previous studies showing a significant bias toward repeated measurements of the same substances due to regulatory needs and the challenges of determining new, previously unmeasured, compounds. Substances listed in the industrial chemical inventories of Europe, China, and the United States accounted for only about 5% of measured substances. However, pharmaceuticals and current use pesticides were widely measured accounting for 50-60% of total CASRN counts for the period 2000-2015.
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Affiliation(s)
- Derek C G Muir
- Environment & Climate Change Canada, Burlington, Ontario L7S1A1, Canada
- School of Environmental Sciences, University of Guelph, Guelph, Ontario N1G2W1, Canada
| | - Gordon J Getzinger
- School of Environmental Sustainability, Loyola University Chicago, Chicago, Illinois 60660, United States
- Department of Civil and Environmental Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Matt McBride
- CAS IP Services, CAS, Columbus, Ohio 43202, United States
| | - P Lee Ferguson
- Department of Civil and Environmental Engineering, Duke University, Durham, North Carolina 27708, United States
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26
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Revell L. Natural halogen-containing compounds cool the climate. Nature 2023; 618:914-915. [PMID: 37380687 DOI: 10.1038/d41586-023-02040-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
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27
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Wu J, Ding S, Fang X, Bai F, Li T, Wang J, Zhang D, Ma T, Yi L, Hu J. Banks, emissions, and environmental impacts of China's ozone depletion substances and hydrofluorocarbon substitutes during 1980-2020. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 882:163586. [PMID: 37087013 DOI: 10.1016/j.scitotenv.2023.163586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 04/13/2023] [Accepted: 04/15/2023] [Indexed: 05/03/2023]
Abstract
Ozone-depleting substances (ODSs), which also contribute to global warming, have been controlled by the Montreal Protocol (MP) since 1987. China joined the MP in 1991 and began reducing production and consumption of ODSs in the country, leading to a decrease in emissions of ODSs. Based on the Intergovernmental Panel on Climate Change guidelines, the latest emission factors and actual consumption in China (MP scenario), both the historical banks and the historical emissions of ODSs and substitute hydrofluorocarbons (HFCs) during 1980-2020 were calculated. To understand the reduction in ODS and HFC emissions by implementing the MP, we also estimated China's virtual emissions (NMP, i.e., the amount of ODS emissions without the MP) over the same period. The avoided cumulative ODS consumption and emission values of 10.8 and 5.8 (4.8-6.9) million tonnes (Mt) of CFC-11-equivalent (eq), respectively, were estimated by comparing the two scenarios. Furthermore, 26 (22-33) giga tonnes (Gt) of CO2-eq emissions, equivalent to an increase of 0.031 W m-2 radiative forcing, were estimated to be avoided by 2020, which will prevent an additional 0.025 °C increase in temperature. The MP implemented by China has resulted in substantial environmental benefits over the last 30 years. However, owing to the massive use of HFCs as substitutes, the cumulative emissions reached 2286 Mt. CO2-eq during 1990-2020, and it will be challenging to phase down HFCs in the environment after China ratified the Kigali Amendment in 2021.
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Affiliation(s)
- Jing Wu
- Institute of Transport Energy and Environment, School of Environment, Beijing Jiaotong University, Beijing 100044, China; The MOE Key Laboratory of Resource and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
| | - Shan Ding
- The MOE Key Laboratory of Resource and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Xuekun Fang
- Collegel of Environmental & Resource Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Fuli Bai
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Tong Li
- The MOE Key Laboratory of Resource and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Jing Wang
- The MOE Key Laboratory of Resource and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Dayu Zhang
- The MOE Key Laboratory of Resource and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Tengfei Ma
- The MOE Key Laboratory of Resource and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China
| | - Liying Yi
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Jianxin Hu
- College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
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Wang S, Li Q, Duan K, Wang B, Zhu X, Wang X, Shen Y, Liu H, Ma Y. Profile of atmospheric VOC over the Yellow Sea, China: A tale of distribution, constraints, and sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161634. [PMID: 36669669 DOI: 10.1016/j.scitotenv.2023.161634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/09/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
In the winter of 2018-2019, 75 air samples were collected through four ship-borne measurements in the Yellow Sea (YS) to assess the levels, confinement processes, and source distribution of volatile organic compounds (VOCs). A total of 41 were eventually detected, which mainly were non-methane hydrocarbons (NMHCs), volatile halogenated hydrocarbons (VHCs), oxygenated volatile organic compounds (OVOCs), and volatile organic sulfur compounds (VSCs). Aromatics (31.93 %) and alkenes (11.04 %) in the atmosphere of the YS accounted for a larger proportion of NMHCs compared with the coastal areas. C3-C5 alkanes, propylene, and chloroform exhibited strong latitudinal gradients and opposite latitudinal distributions in the North and South YS, highlighting the strong contribution of regional outflow to YS's atmosphere. The level of Σ41VOCs increased significantly during the heavy pollution period with some chemical monomers detected, which was further enhanced by the emissions from industrial parks near the Liaodong Peninsula and the Shandong Peninsula. Five main VOC sources were identified by the Positive matrix factorization (PMF) model, which were industrial emissions (13.33 %), fuel use and volatilization (6.67 %), Freon R-22 emissions (33.33 %), oil and gas production (20.00 %), and solvent volatilization (26.67 %). These observations revealed the strong causal relationship between coastal air mass transport and the atmosphere in the marginal sea and emphasized that full attention should be paid to the unintentional and unorganized emission of chemical monomers in the industrial process.
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Affiliation(s)
- Shuang Wang
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Qingbo Li
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China.
| | - Kuiquan Duan
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Baopeng Wang
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Xinyu Zhu
- Dalian Eco-environmental Affairs Service Center, 116026, No. 58 Lianshan Street, Shahekou District, Dalian, China
| | - Xuanya Wang
- China Academy of Transportation Science, 10029, No. 240, Huixinli, Chaoyang District, Beijing, China
| | - Yuxin Shen
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Hui Liu
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Ye Ma
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
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Ameduri B. Fluoropolymers: A special class of per- and polyfluoroalkyl substances (PFASs) essential for our daily life. J Fluor Chem 2023. [DOI: 10.1016/j.jfluchem.2023.110117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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30
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Li X, Li B, Yang Y, Hu L, Chen D, Hu X, Feng R, Fang X. Characteristics and source apportionment of some halocarbons in Hangzhou, eastern China during 2021. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 865:160894. [PMID: 36563752 DOI: 10.1016/j.scitotenv.2022.160894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 11/25/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
In recent years, eastern China has been identified as an important contributor to national and global emissions of halocarbons, some of which are ozone depletion substances (ODSs) that delay the recovery of the stratospheric ozone layer. However, the most recent characteristics and sources of halocarbons in eastern China remain unclear. Thus, hourly atmospheric observations of halocarbons were conducted in Hangzhou throughout 2021. The results showed that methylene chloride (CH2Cl2) was the most abundant halocarbon (2207 (25 %-75 % quantile: 1116-2848) ppt; parts per trillion) followed by chloromethane (CH3Cl) (912 (683-1043) ppt), and 1,2-dichloroethane (CH2ClCH2Cl) (596 (292-763) ppt). Then, backward trajectory and potential source contribution function (PSCF) analysis show that the emission hot spots of halocarbons were concentrated in adjacent cities in Zhejiang and neighboring provinces in eastern China. Moreover, based on positive matrix factorization (PMF) analysis, industrial emission (38.7 %), solvent usage (32.6 %), and the refrigeration sector and biomass burning (23.7 %) were the main sources of halocarbons (observed in this study). This study reveals high concentrations and potential sources of halocarbons in eastern China, which are important for studying the recovery of the ozone layer.
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Affiliation(s)
- Xinhe Li
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Bowei Li
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Yang Yang
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Liting Hu
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Di Chen
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Xiaoyi Hu
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Rui Feng
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Xuekun Fang
- College of Environmental & Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China; State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Center for Global Change Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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31
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Watanabe N, Takahashi M. Theoretical Study of Valence Shell Excitation by Electron Impact in CCl 4. J Phys Chem A 2023; 127:1866-1873. [PMID: 36802640 DOI: 10.1021/acs.jpca.2c08619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
This paper reports a theoretical study of valence shell excitation in CCl4 by high-energy electron impact. Generalized oscillator strengths are calculated for the molecule at the equation-of-motion coupled-cluster singles and doubles level. To elucidate the influence of nuclear dynamics on electron excitation cross-sections, the effects of molecular vibration are included in the calculation. Based on a comparison with recent experimental data, several reassignments of spectral features are made, and it is found that excitations from the Cl 3p nonbonding orbitals to σ* antibonding orbitals, 7a1 and 8t2, play dominant roles below the excitation energy of ∼9 eV. Furthermore, the calculations reveal that distortion of the molecular structure due to the asymmetric stretching vibration significantly affects the valence excitations at small momentum transfers, where contributions from dipole transitions are dominant. It indicates that vibrational effects have a considerable influence on Cl formation in the photolysis of CCl4.
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Affiliation(s)
- Noboru Watanabe
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
| | - Masahiko Takahashi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
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Cao X, Gu D, Li X, Leung KF, Sun H, Mai Y, Chan WM, Liang Z. Characteristics and source origin analysis of halogenated hydrocarbons in Hong Kong. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160504. [PMID: 36464056 DOI: 10.1016/j.scitotenv.2022.160504] [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: 10/04/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
Despite being regulated globally for almost three decades, halocarbon continues to play a vital role in climate change and ozone layer because of its long lifetime in the ambient air. In recent years, unexpected halocarbon emissions have been found in Asia, raising concerns about ozone recovery. As a number of studies focused on halocarbon variations and source profiles, there is an increasing need to identify halocarbon source origins. In this study, an eight-month regular air sampling was conducted at a coastal site in Hong Kong from November 2020 to June 2021, and seventeen halocarbon species were selected for extensive investigation after advanced sample analysis in our laboratory. The temporal variations of halocarbon mixing ratio enhancements were analyzed, and the spatial variations of source origins were investigated by wind sectors and backward trajectory statistics. Our results indicate lower enhancements beyond the background values for major regulated CFCs and CCl4 than later controlled HCFCs and HFCs, suggesting the greater progress of Montreal Protocol implementation for the former species. The notable high enhancement values of non-regulated halocarbons from the north direction indicate their widespread usage in China. The source apportionment analysis estimates the contributions from six emission sectors on measured halocarbons, including solvent usage (43.57 ± 4.08 %), refrigerant residues (17.05 ± 5.71 %), cleaning agent/chemical production (13.18 ± 4.76 %), refrigerant replacements (13.06 ± 2.13 %), solvent residues (8.65 ± 3.28 %), and foaming agent (4.49 ± 1.08 %). Trajectories statistical analysis suggests that industrial solvent was mainly contributed by eastern China (i.e., Shandong and YRD), cleaning agent/chemical production was spread over southeast China (i.e., YRD and Fujian), and refrigeration replacements were dominant in Hong Kong surrounding regions. This work provides insight into the progress made in implementing the Montreal Protocol in Hong Kong and the surrounding region and the importance of continuous emission control.
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Affiliation(s)
- Xiangyunong Cao
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Dasa Gu
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
| | - Xin Li
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Ka Fung Leung
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Hao Sun
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Yuchen Mai
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Wai Ming Chan
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Zhenxing Liang
- Division of Environment and Sustainability, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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33
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How wildfires deplete ozone in the stratosphere. Nature 2023; 615:219-221. [PMID: 36890369 DOI: 10.1038/d41586-023-00598-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2023]
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34
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Das N, De S, Bhatt P, Safvan CP, Majumdar A. Fragmentation dynamics of tetrachloromethane molecule induced by highly charged Ar 7+-ion impact. J Chem Phys 2023; 158:084307. [PMID: 36859097 DOI: 10.1063/5.0135440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
The ion impact multiple ionization and subsequent dissociation of CCl4 is studied using a beam of Ar7+ ion having the energy of about 1 MeV in a linear time- of-flight mass spectrometer, coupled with a position-sensitive detector. The complete, as well as incomplete Coulomb explosion pathways, for CCl4 2+ and CCl4 3+ ions are identified and studied. The kinetic energy release distributions of channels, kinetic energies, and momentum distributions of fragmented ions, as well as neutrals, are also calculated. Possible modes of fragmentation pathways, i.e., concerted and/or sequential, for all the identified channels are studied using Newton diagrams, Dalitz plots, and kinetic energy distributions. The dynamical information and fragmentation pathways were analyzed with the Dalitz plot and Newton diagram for the three-body dissociation channel. The nature of the fragmentation process is further investigated with simulated Dalitz plots and Newton diagrams using the simple classical mechanical model.
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Affiliation(s)
- Nirmallya Das
- Department of Physics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, West Bengal, India
| | - Sankar De
- Saha Institute of Nuclear Physics, A CI of Homi Bhabha National Institute, 1/AF, Bidhannagar, Kolkata 700064, India
| | - Pragya Bhatt
- Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - C P Safvan
- Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Abhijit Majumdar
- Department of Physics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, West Bengal, India
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35
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Brown TFM, Bannister MT, Revell LE. Envisioning a sustainable future for space launches: a review of current research and policy. J R Soc N Z 2023. [DOI: 10.1080/03036758.2022.2152467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Tyler F. M. Brown
- Te Kura Matū School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand
| | - Michele T. Bannister
- Te Kura Matū School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand
| | - Laura E. Revell
- Te Kura Matū School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand
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36
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Larin IK. Biologically Active UV Radiation in the 21st Century. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B 2023. [DOI: 10.1134/s1990793123010074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
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37
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Reaction Mechanism and Kinetics of H and Cl Atom Abstraction in Dichloromethane With OH Radical. COMPUT THEOR CHEM 2023. [DOI: 10.1016/j.comptc.2023.114082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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38
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Akiyoshi H, Kadowaki M, Yamashita Y, Nagatomo T. Dependence of column ozone on future ODSs and GHGs in the variability of 500-ensemble members. Sci Rep 2023; 13:320. [PMID: 36609500 PMCID: PMC9822909 DOI: 10.1038/s41598-023-27635-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/04/2023] [Indexed: 01/09/2023] Open
Abstract
State-of-the-art chemistry-climate models (CCMs) have indicated that a future decrease in ozone-depleting substances (ODSs) combined with an increase in greenhouse gases (GHGs) would increase the column ozone amount in most regions except the tropics and Antarctic. However, large Arctic ozone losses have occurred at a frequency of approximately once per decade since the 1990s (1997, 2011 and 2020), despite the ODS concentration peaking in the mid-1990s. To understand this, CCMs were used to conduct 24 experiments with ODS and GHG concentrations set based on predicted values for future years; each experiment consisted of 500-member ensembles. The 50 ensemble members with the lowest column ozone in the mid- and high latitudes of the Northern Hemisphere showed a clear ODS dependence associated with low temperatures and a strong westerly zonal mean zonal wind. Even with high GHG concentrations, several ensemble members showed extremely low spring column ozone in the Arctic when ODS concentration remained above the 1980-1985 level. Hence, ODS concentrations should be reduced to avoid large ozone losses in the presence of a stable Arctic polar vortex. The average of the lowest 50 members indicates that GHG increase towards the end of the twenty-first century will not cause worse Arctic ozone depletion.
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Affiliation(s)
- Hideharu Akiyoshi
- Earth System Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Masanao Kadowaki
- grid.20256.330000 0001 0372 1485Nuclear Science and Engineering Center, Japan Atomic Energy Agency, 765-1 Funaishikawa, Tokai-mura, Naka-gun, Ibaraki 319-1184 Japan
| | - Yousuke Yamashita
- grid.140139.e0000 0001 0746 5933Earth System Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 Japan ,grid.410588.00000 0001 2191 0132Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Kanagawa 236-0001 Japan
| | - Toshiharu Nagatomo
- grid.140139.e0000 0001 0746 5933Earth System Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 Japan
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39
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RE-NiO (RE=Ce, Y, La) composite oxides coupled plasma catalysis for benzene oxidation and by-product ozone removal. J RARE EARTH 2023. [DOI: 10.1016/j.jre.2023.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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40
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Milillo C, Falcone L, Di Carlo P, Aruffo E, Del Boccio P, Cufaro MC, Patruno A, Pesce M, Ballerini P. Ozone effect on the inflammatory and proteomic profile of human macrophages and airway epithelial cells. Respir Physiol Neurobiol 2023; 307:103979. [PMID: 36243292 DOI: 10.1016/j.resp.2022.103979] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 10/04/2022] [Accepted: 10/09/2022] [Indexed: 11/15/2022]
Abstract
Ozone (O3) is one of the most harmful urban pollutants, but its biological mechanisms have not been fully elucidated yet. Human bronchial epithelial cells (HBEpC) and human macrophage cells (differentiated human monocytic cell line) were exposed to O3 at the concentration of 240 μg/m3 (120 ppb), corresponding to the European Union alert threshold. Cell viability, reactive oxygen species (ROS) production, and pro-inflammatory cytokines release (IL-8 and TNF-α) were evaluated. Results indicated that O3 exposure increases ROS production in both cell types and enhances cytokines release in macrophages. O3 stimulated IL-8 and TNF-α in HBEpC when the cells were pretreated with Lipopolysaccharide, used to mimic a pre-existing inflammatory condition. Proteomics analysis revealed that, in HBEpC, O3 caused the up-regulation of aldo-keto reductase family 1 member B10, a recognized critical protein in lung carcinogenesis. In conclusion, our results show that 120 ppb O3 can lead to potential damage to human health suggesting the need for a revision of the actual alert levels.
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Affiliation(s)
- C Milillo
- Department of Innovative Technologies in Medicine & Dentistry, University G. d'Annunzio, 66100 Chieti, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - L Falcone
- Department of Innovative Technologies in Medicine & Dentistry, University G. d'Annunzio, 66100 Chieti, Italy
| | - P Di Carlo
- Department of Innovative Technologies in Medicine & Dentistry, University G. d'Annunzio, 66100 Chieti, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - E Aruffo
- Department of Innovative Technologies in Medicine & Dentistry, University G. d'Annunzio, 66100 Chieti, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - P Del Boccio
- Department of Pharmacy, University G. d'Annunzio, 66100 Chieti, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - M C Cufaro
- Department of Pharmacy, University G. d'Annunzio, 66100 Chieti, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - A Patruno
- Department of Medicine and Aging Sciences, University G. d'Annunzio, 66100 Chieti, Italy
| | - M Pesce
- Department of Medicine and Aging Sciences, University G. d'Annunzio, 66100 Chieti, Italy.
| | - P Ballerini
- Department of Innovative Technologies in Medicine & Dentistry, University G. d'Annunzio, 66100 Chieti, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
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41
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Microplastic Interactions and Possible Combined Biological Effects in Antarctic Marine Ecosystems. Animals (Basel) 2022; 13:ani13010162. [PMID: 36611770 PMCID: PMC9817852 DOI: 10.3390/ani13010162] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/21/2022] [Accepted: 12/27/2022] [Indexed: 01/03/2023] Open
Abstract
Antarctica and the Southern Ocean are the most remote regions on Earth, and their quite pristine environmental conditions are increasingly threatened by local scientific, tourism and fishing activities and long-range transport of persistent anthropogenic contaminants from lower latitudes. Plastic debris has become one of the most pervasive and ubiquitous synthetic wastes in the global environment, and even at some coastal Antarctic sites it is the most common and enduring evidence of past and recent human activities. Despite the growing scientific interest in the occurrence of microplastics (MPs) in the Antarctic environment, the lack of standardized methodologies for the collection, analysis and assessment of sample contamination in the field and in the lab does not allow us to establish their bioavailability and potential impact. Overall, most of the Southern Ocean appears to be little-affected by plastic contamination, with the exception of some coastal marine ecosystems impacted by wastewater from scientific stations and tourist vessels or by local fishing activities. Microplastics have been detected in sediments, benthic organisms, Antarctic krill and fish, but there is no clear evidence of their transfer to seabirds and marine mammals. Therefore, we suggest directing future research towards standardization of methodologies, focusing attention on nanoplastics (which probably represent the greatest biological risks) and considering the interactions of MPs with macro- and microalgae (especially sea-ice algae) and the formation of epiplastic communities. In coastal ecosystems directly impacted by human activities, the combined exposure to paint chips, metals, persistent organic pollutants (POPs), contaminants of emerging interest (CEI) and pathogenic microorganisms represents a potential danger for marine organisms. Moreover, the Southern Ocean is very sensitive to water acidification and has shown a remarkable decrease in sea-ice formation in recent years. These climate-related stresses could reduce the resilience of Antarctic marine organisms, increasing the impact of anthropogenic contaminants and pathogenic microorganisms.
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42
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Manonmani G, Sandhiya L, Senthilkumar K. A Computational Perspective on the Chemical Reaction of HFO-1234zc with the OH Radical in the Gas Phase and in the Presence of Mineral Dust. J Phys Chem A 2022; 126:9564-9576. [PMID: 36534504 DOI: 10.1021/acs.jpca.2c03229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The gas phase and heterogeneous reaction on mineral dust aerosols of trace gases could significantly affect the tropospheric oxidation capacity and aerosol composition of the atmosphere. In this work, the OH radical-initiated oxidation of a hydrofluoroolefin, HFO-1234zc, and subsequent reaction of favorable intermediates with other reactive species, such as O2, HO2, and NOx (x = 1-2) radicals, were studied, and the role of mineral dust in the form of silicate clusters on the reaction mechanism and rate constant was studied. In the gas phase, OH radical addition to HFO-1234zc is kinetically more favorable than the H-atom abstraction reaction. The calculated reaction energy barrier and thermochemical parameters show that both the initial reactions are more feasible on silicate clusters. Thus, silicates can act as chemical sinks for trapping of hydrofluoroolefins (HFOs). It is found that both gas-phase and heterogeneous reactions are responsible for the transformation of HFOs into fluorinated compounds in the atmosphere. Further, the results show that the ozone creation potential of HFO-1234zc is low, and few of the products are harmful to aquatic organisms. This study provides new insights on the formation of toxic pollutants from the oxidation of HFO-1234zc, which may have significant implications in the troposphere.
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Affiliation(s)
- G Manonmani
- Department of Physics, Bharathiar University, Coimbatore641 046, India
| | - L Sandhiya
- CSIR-National Institute of Science Communication and Policy Research, New Delhi110012, India
| | - K Senthilkumar
- Department of Physics, Bharathiar University, Coimbatore641 046, India
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Hynniewta S, Chandra AK. Atmospheric chemistry of methoxyflurane: Reaction with Cl atoms and further degradation. INT J CHEM KINET 2022. [DOI: 10.1002/kin.21623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
| | - Asit K. Chandra
- Department of Chemistry North‐Eastern Hill University Shillong India
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Scheringer M, Johansson JH, Salter ME, Sha B, Cousins IT. Stories of Global Chemical Pollution: Will We Ever Understand Environmental Persistence? ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:17498-17501. [PMID: 36458501 DOI: 10.1021/acs.est.2c06611] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Affiliation(s)
- Martin Scheringer
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, 8092 Zürich, Switzerland
- RECETOX, Masaryk University, 625 00 Brno, Czech Republic
| | - Jana H Johansson
- Department of Thematic Studies - Environmental Change, Linköping University, 581 83 Linköping, Sweden
| | - Matthew E Salter
- Department of Environmental Science, Stockholm University, 10691 Stockholm, Sweden
| | - Bo Sha
- Department of Environmental Science, Stockholm University, 10691 Stockholm, Sweden
| | - Ian T Cousins
- Department of Environmental Science, Stockholm University, 10691 Stockholm, Sweden
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Ricker H, Leonardi A, Navea JG. Reduction and Photoreduction of NO 2 in Humic Acid Films as a Source of HONO, ClNO, N 2O, NO X , and Organic Nitrogen. ACS EARTH & SPACE CHEMISTRY 2022; 6:3066-3077. [PMID: 36561196 PMCID: PMC9762234 DOI: 10.1021/acsearthspacechem.2c00282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/18/2022] [Accepted: 11/21/2022] [Indexed: 06/17/2023]
Abstract
Atmospheric nitrous acid (HONO), a trace atmospheric gas, is often underestimated in global atmospheric models due to the poor understanding of its daytime sources and sinks. HONO is known to accumulate during nighttime and undergo rapid photodissociation during the day to form NO and highly reactive OH radical, making it important to have accurate atmospheric HONO estimations. Despite its rapid photolysis, recent field observations have found quasi-steady-state concentrations of HONO at midday, suggesting photolytic HONO formation pathways to replenish daytime atmospheric HONO. Recent studies suggest that the presence of complex organic photosensitizers in atmospheric aerosols converts atmospheric NO2 into HONO. To better understand the effect of environmental photosensitizers in daytime mechanisms of HONO formation, we present here laboratory studies on the heterogeneous photolytic reduction of NO2 by humic acid films, a proxy for organic chromophoric compounds. The effect of pH and Cl- in the photosensitized formation of HONO and other nitrogen-containing gases is also investigated. A dual Fourier transform infrared (FTIR) system is utilized to simultaneously perform in situ analysis of condensed-phase reactants and gas-phase products. We find that the rate of HONO formation is faster at lower pHs. Nitrogen incorporation in the complex organic chromophore is observed, suggesting a competing pathway that results in suppressed daytime formation of nitrogenous gases. Significantly, the presence of chloride ions also leads to the organic-mediated photolytic formation of nitrosyl chloride (ClNO), a known precursor of HONO. Overall, this work shows that organic acid photosensitizers can reduce adsorbed NO2 to form HONO, ClNO, and NO while simultaneously incorporating nitrogen into the organic chromophores present in aerosol.
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Relationship between ozone and biologically relevant UV at 4 NDACC sites. PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES : OFFICIAL JOURNAL OF THE EUROPEAN PHOTOCHEMISTRY ASSOCIATION AND THE EUROPEAN SOCIETY FOR PHOTOBIOLOGY 2022; 21:2095-2114. [PMID: 35962279 DOI: 10.1007/s43630-022-00281-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 07/25/2022] [Indexed: 12/13/2022]
Abstract
Clouds and aerosols, as well as overhead ozone, can have large effects on ultraviolet (UV) irradiances. We use statistical methods to remove cloud effects and mean aerosol effects from spectral UV irradiance measurements to investigate the relationship between UV and total column ozone. We show that for fixed solar zenith angles (SZA), seasonal changes in ozone lead to marked changes in clear-sky UV irradiances. Such effects are larger at mid-latitudes than in the tropics. At mid-latitudes, the minimum ozone amount over the course of a year can be about 50 percent of its maximum, with the lowest values in autumn and the highest values in spring. These seasonal ozone changes lead to UV Index (UVI) values in autumn that can exceed those in spring at the same SZA by nearly a factor of two. Differences are even larger for UV spectra weighted by the action spectra for DNA-damaging UV, and for cutaneous previtamin D production. In some cases, the seasonal increase exceeds a factor of 4. The analysis experimentally demonstrates the limits of applicability of the concept of constant Radiative Amplification Factors (RAFs) for estimating effects of changes in ozone for some weighting functions. Changes in DNA-weighted UV and erythemally weighted UV are well represented by the published RAFs. However, there are large SZA dependencies in the case of UVB and vitamin D-weighted UV. For all weightings considered, RAFs calculated from the observations as a function of SZA show similar dependencies between sites, in good agreement with published values, independently of the ozone data source. High quality measurements show that natural variations in ozone are responsible for huge variations in biologically damaging UV, with seasonal changes at fixed solar zenith angles sometimes exceeding a factor of four. The measured changes from thousands of spectra agree well with calculations over a wide range of solar zenith angles.
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Lu QB. Response to “Comment on ‘Observation of large and all-season ozone losses over the tropics’” [AIP Adv. 12, 075006 (2022)]. AIP ADVANCES 2022; 12. [DOI: 10.1063/5.0129344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Affiliation(s)
- Qing-Bin Lu
- Department of Physics and Astronomy and Departments of Biology and Chemistry, University of Waterloo , 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
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Chakma M, Usmani O. Inhalers and the Environment: Pollution, Plastics and Policy. PNEUMON 2022. [DOI: 10.18332/pne/154608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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DFT study on aerial degradation of product radicals derived from the reaction of 1H–Heptafluorocyclopentene (cyc‐CF2CF2CF2CF = CH − ) with OH radical. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2022.113915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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50
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Velázquez-Guillén R, Rivera-Toledo M. A methodology for propellant composition optimization in aerosol consumer products, considering economic, safety, and environmental objectives. Comput Chem Eng 2022. [DOI: 10.1016/j.compchemeng.2022.108069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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