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Marin-Rimoldi E, Yancey AD, Shiflett MB, Maginn EJ. Adsorption of difluoromethane (HFC-32) and pentafluoroethane (HFC-125) and their mixtures in silicalite-1: An experimental and Monte Carlo simulation study. J Chem Phys 2024; 161:074701. [PMID: 39145562 DOI: 10.1063/5.0221413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Accepted: 07/29/2024] [Indexed: 08/16/2024] Open
Abstract
Hydrofluorocarbons are a class of fluorinated molecules used extensively in residential and industrial refrigeration systems. This study examines the potential of using adsorption processes with the silicalite-1 zeolite to separate a mixture of difluoromethane (CH2F2, HFC-32) and pentafluoroethane (CF3CF2H, HFC-125) at various concentrations. Pure adsorption data were measured using a XEMIS gravimetric microbalance, whereas binary data were determined using the Integral Mass Balance method. Grand canonical Monte Carlo molecular simulations were performed with the Cassandra package. We found that the results from molecular simulations are in satisfactory agreement with experimental loading measurements. Moreover, we show that ideal adsorbed solution theory could not quantitatively match the experimental or computational measurements of binary adsorption or selectivity. Molecular simulations show that refrigerant molecules do not have a uniform distribution in the zeolite framework.
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Affiliation(s)
- Eliseo Marin-Rimoldi
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Andrew D Yancey
- Department of Chemical and Petroleum Engineering, University of Kansas, Lawrence, Kansas 66045, USA
- Wonderful Institute for Sustainable Engineering, University of Kansas, Lawrence, Kansas 66045, USA
| | - Mark B Shiflett
- Department of Chemical and Petroleum Engineering, University of Kansas, Lawrence, Kansas 66045, USA
- Wonderful Institute for Sustainable Engineering, University of Kansas, Lawrence, Kansas 66045, USA
| | - Edward J Maginn
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA
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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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Metagenomic- and Cultivation-Based Exploration of Anaerobic Chloroform Biotransformation in Hypersaline Sediments as Natural Source of Chloromethanes. Microorganisms 2020; 8:microorganisms8050665. [PMID: 32370295 PMCID: PMC7284496 DOI: 10.3390/microorganisms8050665] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 04/22/2020] [Accepted: 04/29/2020] [Indexed: 01/23/2023] Open
Abstract
Chloroform (CF) is an environmental contaminant that can be naturally formed in various environments ranging from forest soils to salt lakes. Here we investigated CF removal potential in sediments obtained from hypersaline lakes in Western Australia. Reductive dechlorination of CF to dichloromethane (DCM) was observed in enrichment cultures derived from sediments of Lake Strawbridge, which has been reported as a natural source of CF. No CF removal was observed in abiotic control cultures without artificial electron donors, indicating biotic CF dechlorination in the enrichment cultures. Increasing vitamin B12 concentration from 0.04 to 4 µM in enrichment cultures enhanced CF removal and reduced DCM formation. In cultures amended with 4 µM vitamin B12 and 13C labelled CF, formation of 13CO2 was detected. Known organohalide-respiring bacteria and reductive dehalogenase genes were neither detected using quantitative PCR nor metagenomic analysis of the enrichment cultures. Rather, members of the order Clostridiales, known to co-metabolically transform CF to DCM and CO2, were detected. Accordingly, metagenome-assembled genomes of Clostridiales encoded enzymatic repertoires for the Wood-Ljungdahl pathway and cobalamin biosynthesis, which are known to be involved in fortuitous and nonspecific CF transformation. This study indicates that hypersaline lake microbiomes may act as a filter to reduce CF emission to the atmosphere.
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Reichel M, Egenhöfer M, Krumm B, Karaghiosoff K. Fluorine in Small Molecules: Fluoromethyl Azide and Chalcogenocyanates. Z Anorg Allg Chem 2020. [DOI: 10.1002/zaac.202000055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marco Reichel
- Department of Chemistry Ludwig‐Maximilian University of Munich Butenandtstr. 5–13(D) 81377 Munich Germany
| | - Mara Egenhöfer
- Department of Chemistry Ludwig‐Maximilian University of Munich Butenandtstr. 5–13(D) 81377 Munich Germany
| | - Burkhard Krumm
- Department of Chemistry Ludwig‐Maximilian University of Munich Butenandtstr. 5–13(D) 81377 Munich Germany
| | - Konstantin Karaghiosoff
- Department of Chemistry Ludwig‐Maximilian University of Munich Butenandtstr. 5–13(D) 81377 Munich Germany
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Yuan D, He Z, Yang GP. Spatiotemporal distributions of halocarbons in the marine boundary air and surface seawater of the Changjiang estuary and its adjacent East China Sea. MARINE POLLUTION BULLETIN 2019; 140:227-240. [PMID: 30803638 DOI: 10.1016/j.marpolbul.2019.01.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 01/21/2019] [Accepted: 01/21/2019] [Indexed: 06/09/2023]
Abstract
Spatiotemporal distributions of volatile halogenated organic compounds (VHOCs) were investigated in the marine boundary air and surface seawater of the Changjiang (Yangtze River) estuary and its adjacent East China Sea in two cruises from March 11, 2015 to March 21, 2015 and from July 9, 2015 to July 20, 2015. Results revealed that the concentrations of released chlorofluorocarbons (CFCs) such as CFC-12, CFC-11, and CFC-114 in China decreased, suggesting that limitations set by the Chinese government on CFCs production and consumption have taken effect. Atmospheric concentrations of CFCs were affected by local industrial sources of emission and transport of terrestrial pollutants from coastal areas to varying degrees. Seasonal variations in atmospheric VHOCs were probably due to seasonal differences in prevalent monsoon and biogenic production. In the study periods, the investigated area was an essential source of atmospheric CH3Br and CH3I but was a net sink of CFC-12, CFC-11, and CH3Cl.
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Affiliation(s)
- Da Yuan
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education / Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, China; Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Shandong Provincial Key Laboratory of Ocean Environmental Monitoring Technology, National Engineering and Technological Research Center of Marine Monitoring Equipment, No 7 Miaoling Road, 266061 Qingdao, China
| | - Zhen He
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education / Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, China; Institute of Marine Chemistry, Ocean University of China, Qingdao 266100, China
| | - Gui-Peng Yang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education / Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Institute of Marine Chemistry, Ocean University of China, Qingdao 266100, China.
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Abstract
Photooxidation of tetrachloroethylene (PERC) and trichloroethylene (TCE) in simulated tropospheric smog chamber studies occurs with a time delay, accelerating simultaneous decreasing O3/chlorinated ethylene (CE) concentrations along with increasing CCl2O, which is attributed to CCl2 in the case of PERC and CCl2 or CHCl for TCE. The carbenes, chlorinated acetyl chlorides and CCl2O products may result from the rearrangement of the oxidised and/or excited oxidised CE, e.g. an epoxide. Analyses indicate scavenging experiments have not proved the existence of Cl atoms as being responsible for chlorinated acetyl chloride formation. Halocarbenes may form complexes with O3 which can undergo electron transfer (ET) and lead to dissociation of O3 to O2 and O and regeneration of carbene, resulting in a chain reaction. The direction of ET may be determined by the smallest differential HOMO–LUMO energy between the carbene and O3 which results in greater transition state stabilisation. Similarities in the reactions of O3 with carbenes and simple alkenes, nucleophilic carbenes with electron-poor alkenes and electrophilic carbene PhCCl with alkyl-substituted alkenes, i.e. (1) complex formation, (2) very low or negative activation energies and (3) the ability to undergo ET reactions with alkylalkenes are discussed. The possibility of the world-wide used perhalocarbons, e.g. perfluorinated carbons, hydroperhalocarbons, their halogenated replacements and starting materials degrading to halocarbenes which may degrade O3, is analysed.
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Affiliation(s)
- Andrew Mamantov
- Formerly of: US Environmental Protection Agency, Washington, DC, USA
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8
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Patel M, Kim HS, Park HH, Kim J. Active Adoption of Void Formation in Metal-Oxide for All Transparent Super-Performing Photodetectors. Sci Rep 2016; 6:25461. [PMID: 27151288 PMCID: PMC4858702 DOI: 10.1038/srep25461] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 04/18/2016] [Indexed: 12/28/2022] Open
Abstract
Could ‘defect-considered’ void formation in metal-oxide be actively used? Is it possible to realize stable void formation in a metal-oxide layer, beyond unexpected observations, for functional utilization? Herein we demonstrate the effective tailoring of void formation of NiO for ultra-sensitive UV photodetection. NiO was formed onto pre-sputtered ZnO for a large size and spontaneously formed abrupt p-NiO/n-ZnO heterojunction device. To form voids at an interface, rapid thermal process was performed, resulting in highly visible light transparency (85–95%). This heterojunction provides extremely low saturation current (<0.1 nA) with an extraordinary rectifying ratio value of over 3000 and works well without any additional metal electrodes. Under UV illumination, we can observe the fast photoresponse time (10 ms) along with the highest possible responsivity (1.8 A W−1) and excellent detectivity (2 × 1013 Jones) due to the existence of an intrinsic-void layer at the interface. We consider this as the first report on metal-oxide-based void formation (Kirkendall effect) for effective photoelectric device applications. We propose that the active adoption of ‘defect-considered’ Kirkendall-voids will open up a new era for metal-oxide based photoelectric devices.
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Affiliation(s)
- Malkeshkumar Patel
- Department of Electrical Engineering, Incheon National University, 119 Academy Rd. Yeonsu, Incheon, 406772, Republic of Korea
| | - Hong-Sik Kim
- Department of Electrical Engineering, Incheon National University, 119 Academy Rd. Yeonsu, Incheon, 406772, Republic of Korea
| | - Hyeong-Ho Park
- Applied Device and Material Lab., Device Technology Division, Korea Advanced Nanofab Center (KANC), Suwon 443270, Korea
| | - Joondong Kim
- Department of Electrical Engineering, Incheon National University, 119 Academy Rd. Yeonsu, Incheon, 406772, Republic of Korea
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9
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Feller M, Lux K, Kornath A. Crystal Structure and Spectroscopic Investigation of Bromofluoro- and Fluoroiodomethane. Eur J Inorg Chem 2015. [DOI: 10.1002/ejic.201500759] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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10
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Zhu B, Traini D, Chan HK, Young PM. The effect of ethanol on the formation and physico-chemical properties of particles generated from budesonide solution-based pressurized metered-dose inhalers. Drug Dev Ind Pharm 2013; 39:1625-37. [DOI: 10.3109/03639045.2012.728230] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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11
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Bojkov R, Bishop L, Hill WJ, Reinsel GC, Tiao GC. A statistical trend analysis of revised Dobson total ozone data over the northern hemisphere. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jd095id07p09785] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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Lazrus AL, Gandrud BW, Woodard RN, Sedlacek WA. Direct measurements of stratospheric chlorine and bromine. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jc081i006p01067] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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13
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Liu SC, Donahue TM, Cicerone RJ, Chameides WL. Effect of water vapor on the destruction of ozone in the stratosphere perturbed by ClX or NOxpollutants. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jc081i018p03111] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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14
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Cicerone RJ. Comment on ‘Volcanic emissions of halides and sulfur compounds to the troposphere and stratosphere’ by R. D. Cadle. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jc080i027p03911] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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15
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Rundel RD, Stolarski RS. A reexamination of the photochemistry of the Cl2-O3system. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jc081i033p05759] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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16
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Riegler GR, Drake JF, Liu SC, Cicerone RJ. Stellar occultation measurements of atmospheric ozone and chlorine from OAO 3. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja081i028p04997] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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17
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Atkinson R, Breuer GM, Pitts JN, Sandoval HL. Tropospheric and stratospheric sinks for halocarbons: Photooxidation, O(1D) atom, and OH radical reactions. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jc081i033p05765] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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18
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Tassi F, Capecchiacci F, Cabassi J, Calabrese S, Vaselli O, Rouwet D, Pecoraino G, Chiodini G. Geogenic and atmospheric sources for volatile organic compounds in fumarolic emissions from Mt. Etna and Vulcano Island (Sicily, Italy). ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd017642] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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20
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Abstract
Freons are a potential source of stratospheric chlorine and may indirectly cause serious reductions in the concentration of ozone. The reduction could be as large as 3 percent by 1980, or 16 percent by 2000, if Freon consumption were to grow at 10 percent per year. Even if Freon use were terminated as early as 1990, it could leave a significant effect which might endure for several hundred years.
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Abstract
Regulations to limit the use of trichloroethylene as a degreasing solvent have led to an increased use of the more photochemically inert solvent methyl chloroform as a substitute. Model calculations show that about 15 percent of the methyl chloroform released into the atmosphere will reach the stratosphere. Time scenarios based on past production figures and reasonable projections for future release rates lead to a steady-state ozone depletion due to this solvent about 20 percent as large as those resulting from the continuous release of chlorofluoromethanes at 1973 rates.
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Hua L, Zhang X, Lee WB, Chao MH, Zhang B, Lin KC. Photodissociation of cis-, trans-, and 1,1-Dichloroethylene in the Ultraviolet Range: Characterization of Cl(2PJ) Elimination. J Phys Chem A 2009; 114:37-44. [DOI: 10.1021/jp907030e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Linqiang Hua
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China, Graduate School of the Chinese Academy of Sciences, Beijing 10039, P. R. China, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
| | - Xiaopeng Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China, Graduate School of the Chinese Academy of Sciences, Beijing 10039, P. R. China, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
| | - Wei-Bin Lee
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China, Graduate School of the Chinese Academy of Sciences, Beijing 10039, P. R. China, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
| | - Meng-Hsuan Chao
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China, Graduate School of the Chinese Academy of Sciences, Beijing 10039, P. R. China, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
| | - Bing Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China, Graduate School of the Chinese Academy of Sciences, Beijing 10039, P. R. China, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
| | - King-Chuen Lin
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China, Graduate School of the Chinese Academy of Sciences, Beijing 10039, P. R. China, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
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23
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Kozuch S, Shaik S. Kinetic-Quantum Chemical Model for Catalytic Cycles: The Haber−Bosch Process and the Effect of Reagent Concentration. J Phys Chem A 2008; 112:6032-41. [DOI: 10.1021/jp8004772] [Citation(s) in RCA: 249] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Sason Shaik
- Institute of Chemistry and The Lise Meitner-Minerva Center for Computational Quantum Chemistry, Givat Ram Campus, Jerusalem 91904, Israel
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24
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Chimphango SBM, Brown CF, Musil CF, Dakora FD. Effects of UV-B radiation on seed yield of Glycine max and an assessment of F1 generation progeny for carryover effects. PHYSIOLOGIA PLANTARUM 2007; 131:378-86. [PMID: 18251877 DOI: 10.1111/j.1399-3054.2007.00966.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Glycine max (L.) Merr plants were grown outdoors in potted sand exposed to elevated ultraviolet-B (UV-B) radiation provided by filtered fluorescent lamps to determine the effects of UV-B on seed yield and UV-B-induced carryover effects in the F1 generation. Increased UV-B radiation had no detectable effects on reproductive parameters except for a reduction on seed number per plant and an increase in the number of unseeded pods per plant and dry weight of unseeded pods per plant in the field supplemental UV-B experiment. Studies on carryover effects in the greenhouse progeny growth trial also showed no effect of parental treatment with UV-B on biomass production, and most symbiotic-N traits and plant metabolite measured. However, the concentrations of N in nodules and starch in roots were significantly increased in the F1 generation progeny from elevated UV-B radiation relative to their F1 counterparts from ambient radiation. Assessing the effects of seed size on plant growth and symbiotic function in the F1 progeny showed that total biomass, dry matter yield of individual organs (leaves, stems, roots and nodules), total plant N and fixed-N rose with increasing seed size. Seed concentration of flavonoids was also enhanced with increasing seed size. These findings suggest that subtle changes did occur in the F1 generation progeny of parental plants exposed to elevated UV-B with potential to accumulate with further exposure to elevated UV-B radiation.
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Affiliation(s)
- Samson B M Chimphango
- Botany Department, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
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25
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Tyson BJ. Chlorinated Hydrocarbons in the Atmosphere—Analysis at The Parts-Per-Trillion Level by Gc-Ms. ANAL LETT 2006. [DOI: 10.1080/00032717508059053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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26
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Cohen RC, Murphy JG. Photochemistry of NO2 in Earth's Stratosphere: Constraints from Observations. Chem Rev 2003; 103:4985-98. [PMID: 14664640 DOI: 10.1021/cr020647x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ronald C Cohen
- Department of Chemistry, University of California, Berkeley, CA 94720-1460, USA
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27
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Adsorption equilibria characteristics of some chlorinated cleaning solvent vapors (CFC-113 and HCFC-141b). KOREAN J CHEM ENG 2003. [DOI: 10.1007/bf02697256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Kim SJ, Cho SY, Kim TY. Adsorption of chlorinated volatile organic compounds in a fixed bed of activated carbon. KOREAN J CHEM ENG 2002. [DOI: 10.1007/bf02706875] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Tyrrell J, Kar T, Bartolotti LJ. A Study of the Mechanism of the Reaction between Ozone and the Chlorine Atom Using Density Functional Theory. J Phys Chem A 2001. [DOI: 10.1021/jp001868e] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- James Tyrrell
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Carbondale, Illinois 62901
| | - Tapas Kar
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, Carbondale, Illinois 62901
| | - Libero J. Bartolotti
- North Carolina Supercomputing Center, 3021 Cornwallis Rd., Research Triangle Park, North Carolina 27709
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30
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Snels M, D'Amico G, Piccarreta L, Hollenstein H, Quack M. Diode-Laser Jet Spectra and Analysis of the nu(1) and nu(4) Fundamentals of CCl(3)F. JOURNAL OF MOLECULAR SPECTROSCOPY 2001; 205:102-109. [PMID: 11148113 DOI: 10.1006/jmsp.2000.8241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
High-resolution infrared spectra have been measured for mixtures of CCl(3)F in Ne, expanded in a supersonic planar jet. We present the first analysis for the nu(4) fundamental and a complete analysis for the nu(1) band. Accurate spectroscopic constants have been obtained for both the nu(1) fundamental of the most abundant isotopic species, C(35)Cl(3)F, C(35)Cl(2)(37)ClF, and C(35)Cl(37)Cl(2)F. With respect to an earlier work [M. Snels, A. Beil, H. Hollenstein, M. Quack, U. Schmidt, and F. D'Amato, J. Chem. Phys. 103, 8846-8853 (1995)], the observation of Q branches of the three most abundant isotopomers allowed for an unambiguous determination of the nu(1) band origins. The nu(4) fundamental has not been the subject of a high-resolution analysis up to now. The observation of high-resolution spectra of the central part of the band permitted the determination of band origin, rotational constants, and Coriolis constant for the symmetric-top species, C(35)Cl(3)F. Copyright 2001 Academic Press.
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Affiliation(s)
- M Snels
- Istituto per Materiali Speciali, CNR, Potenza, I-85050, Italy
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Abstract
Lanzhou city is located in north central China near inner Mongolia. The solar UV-B background radiation in this area is occasionally extremely high (8 microW/cm2). Such high background solar UV-B radiation could be attributed to the sporadic depletion of the ozone layer in the stratosphere. The excessive UV-B radiation is a potential hazard in the environment. This prompted the present study on the effect of UV-B radiation on the cytogenetic damage to pollen mother cells of the plant Tradescantia. The Tradescantia-micronucleus (Trad-MCN) test was used to determine the genotoxicity of UV-B radiation. In addition to the usual 10 h of solar emission of UV light a series of increasing dosages (2, 4, 6, 8 h) of artificial UV-B radiation was applied to Tradescantia (clone 3) plant cuttings. Inflorescences of the treated and control plants were fixed and used for preparation of microslides. Micronuclei frequencies were observed in the early tetrads to show the degree of genotoxicity. Results of two repeated experiments show a dose-related increase of MCN frequencies under normal sunshine days. In the third experiment conducted under a cloudy and rainy day and an extraordinary high solar UV-B background, the MCN frequencies were markedly higher than that of the negative control but did not show the clear dose response to the treatment as in the first two experiments. The Trad-MCN test has successfully detected the effect of artificial UV-B radiation over the solar UV-B background radiation.
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Affiliation(s)
- S Wang
- Department of Biology, Lanzhou University, Lanzhou, 730000, China
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32
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Hwang DY, Mebel AM. Ab initio study on the reaction mechanism of ozone with the chlorine atom. J Chem Phys 1998. [DOI: 10.1063/1.477781] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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33
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The nitrogen cycle: perturbations due to man and their impact on atmospheric N
2
O and O
3. ACTA ACUST UNITED AC 1997. [DOI: 10.1098/rstb.1977.0009] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Features of the global cycle of fixed nitrogen are reviewed with an emphasis on perturbations due to man. It is argued that agricultural practices and combustion may lead to an increase in the concentration of atmospheric N
2
O with consequent effects on 0
3
. The level of 0
3
may drop by about 20 % over the next 100 years if world population and the demand for food should continue to grow at anything like rates which prevailed in the recent past. Uncertainties in the model are highlighted and note is taken of areas where there is need for additional data.
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35
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Crutzen PJ. Mein Leben mit O3, NOx und anderen YZOx-Verbindungen (Nobel-Vortrag). Angew Chem Int Ed Engl 1996. [DOI: 10.1002/ange.19961081604] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Cho SY, Choi DK. Langmuir parameters for adsorption of two halogenated chemicals on an activated carbon pellet. KOREAN J CHEM ENG 1996. [DOI: 10.1007/bf02705970] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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37
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Cho SY, Lee TJ, Kim SJ. Equilibria of trichloromonofluoromethane on a carbon pellet. KOREAN J CHEM ENG 1996. [DOI: 10.1007/bf02705943] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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38
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39
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Satellite confirmation of the dominance of chlorofluorocarbons in the global stratospheric chlorine budget. Nature 1996. [DOI: 10.1038/379526a0] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Snels M, Beil A, Hollenstein H, Quack M, Schmitt U, D’Amato F. Rotational analysis of the ν1band of trichlorofluoromethane from high resolution Fourier transform and diode laser spectra of supersonic jets and isotopically enriched samples. J Chem Phys 1995. [DOI: 10.1063/1.470073] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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41
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Hindle M, Newton DA, Chrystyn H. Dry powder inhalers are bioequivalent to metered-dose inhalers. A study using a new urinary albuterol (salbutamol) assay technique. Chest 1995; 107:629-33. [PMID: 7874928 DOI: 10.1378/chest.107.3.629] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Metered-dose inhalers (MDIs) are extensively used to deliver drugs to the lungs but are driven by chlorofluorocarbon (CFC) propellants. The worldwide phasing out of CFCs within the next 5 to 10 years presents difficulties to the pharmaceutical industry. The mean +/- SD relative lung bioavailability of albuterol to the lung following inhalation of 400 micrograms of albuterol from an MDI, the Rotahaler and Diskhaler in 10 well-trained volunteers, was 2.83 (0.78), 1.72 (0.99), and 2.64 (1.23)%, respectively, expressed as a percentage of the nominal dose. The delivery of albuterol to the lungs from the MDI and Diskhaler was similar. In nine asthmatic subjects, the relative lung bioavailability of albuterol following inhalation with the MDI and Diskhaler was 1.19 (0.79) and 2.38 (1.46)%, respectively, expressed as a percentage of the nominal dose. There was no difference in reversibility 30 min after administration of the dose by the two methods. Similar lung deposition from the Diskhaler in volunteers probably is due to efficient MDI technique, which was absent in the asthmatic subjects. The Diskhaler does not rely on coordination during inhalation and therefore is easier to use.
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Affiliation(s)
- M Hindle
- Postgraduate Studies in Pharmaceutical Technology, School of Pharmacy, University of Bradford, West Yorkshire, United Kingdom
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42
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Bojkov RD, Bishop L, Fioletov VE. Total ozone trends from quality-controlled ground-based data (1964–1994). ACTA ACUST UNITED AC 1995. [DOI: 10.1029/95jd02907] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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43
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Cho SY, Lee YY, Chun HS. Adsorption equilibria of CFC-113 on two adsorbents. JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 1995. [DOI: 10.1252/jcej.28.212] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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44
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George C, Lagrange J, Lagrange P, Mirabel P, Pallares C, Ponche JL. Heterogeneous chemistry of trichloroacetyl chloride in the atmosphere. ACTA ACUST UNITED AC 1994. [DOI: 10.1029/93jd02915] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kodama K, Kaguei S, Wakao N. Batch adsorption of trichlorotrifluoroethane (freon-113) onto activated carbon - surface diffusivity and pore diffusivity. CAN J CHEM ENG 1992. [DOI: 10.1002/cjce.5450700206] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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46
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Ko MKW, Sze ND, Weisenstein DK. The roles of dynamical and chemical processes in determining the stratospheric concentration of ozone in one-dimensional and two-dimensional models. ACTA ACUST UNITED AC 1989. [DOI: 10.1029/jd094id07p09889] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Baumann H, Heumann KG. Analysis of organobromine compounds and HBr in motor car exhaust gases with a GC/microwave plasma system. ACTA ACUST UNITED AC 1987. [DOI: 10.1007/bf00469815] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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49
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50
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A Comparison of the Effects of Enhanced UV-B Radiation on Some Crop Plants Exposed to Greenhouse and Field Conditions. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/s0015-3796(85)80042-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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