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James Farquhar - One of the best experts on this subject based on the ideXlab platform.
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Quadruple Sulfur isotope constraints on the origin and cycling of volatile Organic Sulfur Compounds in a stratified sulfidic lake
Geochimica et Cosmochimica Acta, 2013Co-Authors: Harry Oduro, Alexey Kamyshny, Aubrey L. Zerkle, James FarquharAbstract:AbstractWe have quantified the major forms of volatile Organic Sulfur Compounds (VOSCs) distributed in the water column ofstratified freshwater Fayetteville Green Lake (FGL), to evaluate the biogeochemical pathways involved in their production.The lake’s anoxic deep waters contain high concentrations of sulfate (12–16 mmol L 1 ) and sulfide (0.12 lmol L 1 to1.5 mmol L 1 ) with relatively low VOSC concentrations, ranging from 0.1 nmol L to 2.8 lmol L 1 . Sulfur isotope measure-ments of combined volatile Organic Sulfur Compounds demonstrate that VOSC species are formed primarily from reducedSulfur (H 2 S/HS ) and zero-valent Sulfur (ZVS), with little input from sulfate. Thedata support a role of a combination ofbiological and abiotic processes in formation of carbon–Sulfur bonds between reactive Sulfur species and methyl groups oflignin components. These processes are responsible for very fast turnover of VOSC species, maintaining their low levels inFGL. No dimethylsulfoniopropionate (DMSP) was detected by Electrospray Ionization Mass Spectrometry (ESI-MS) inthe lake water column or in planktonic extracts. These observations indicate a pathway distinct from oceanic and coastal mar-ine environments, where dimethylsulfide (DMS) and other VOSC species are principally produced via the breakdown ofDMSP by plankton species. 2013 Elsevier Ltd. All rights reserved.1. INTRODUCTIONThe use of stable isotopes to understand the biogeo-chemical cycling of Sulfur in oceanic (Rees et al., 1978;Jorgensen et al., 2004; Bo¨ttcher et al., 2006), freshwater(Fry, 1986; Canfield et al., 2010; Zerkle et al., 2010), andterrestrial systems (Goldhaber and Kaplan, 1980; Habichtand Canfield, 2001) has focused mostly on the dynamicsof inOrganic sulfate, sulfide and their intermediate species.Few studies (e.g., Amrani et al., 2009; Oduro et al., 2011)have examined Organic Sulfur Compounds, such as dimeth-ylsulfide (DMS; CH
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Multiple Sulfur isotope analysis of volatile Organic Sulfur Compounds and their sulfonium precursors in coastal marine environments
Marine Chemistry, 2011Co-Authors: Harry Oduro, Alexey Kamyshny, Weifu Guo, James FarquharAbstract:Abstract Volatile methylated Sulfur Compounds emitted from terrestrial and aquatic ecosystems play a significant role in the global Sulfur cycle, yet no satisfactory methods are available to trace their source and transformation in natural systems. Here we present a method for quantification and multiple Sulfur isotopic analysis of a variety of volatile Sulfur species as well as their natural precursors via hydrodeSulfurization with a Raney nickel catalyst. The detection limit of this method for methanethiol (MT), dimethylsulfide (DMS), dimethyldisulfide (DMDS), and carbon disulfide (CS 2 ) is 0.2 mg of Sulfur per sample. Average recovery of ~ 95% was attained for samples containing more than 1.3 mg of these Sulfur Compounds. Triplicate to quadruplicate Sulfur isotopic analyses of reduced standard materials yield average standard deviations of 0.3‰, 0.02‰, and 0.1‰, respectively, for δ 34 S, ∆ 33 S, and ∆ 36 S. The method developed here was used for determination of Sulfur isotopic compositions of volatile Organic Sulfur Compounds (VOSCs) and their precursor dimethylsulfoniopropionoate (DMSP) in sediment cores and a C 4 plant Spartina alterniflora collected from the Delaware Great Marsh. Application of the method to these natural samples indicates that the S-isotope compositions of VOSCs and DMSP-S are similar to, but slightly 34 S-depleted (~0.6–0.9), relative to porewater sulfide. These Compounds are 34 S-enriched (~ 1.7–2.0‰) relative to the compositions of the coexisting sulfide. Both suggest a relationship between source sulfide and these Organic Sulfur Compounds.
Harry Oduro - One of the best experts on this subject based on the ideXlab platform.
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Quadruple Sulfur isotope constraints on the origin and cycling of volatile Organic Sulfur Compounds in a stratified sulfidic lake
Geochimica et Cosmochimica Acta, 2013Co-Authors: Harry Oduro, Alexey Kamyshny, Aubrey L. Zerkle, James FarquharAbstract:AbstractWe have quantified the major forms of volatile Organic Sulfur Compounds (VOSCs) distributed in the water column ofstratified freshwater Fayetteville Green Lake (FGL), to evaluate the biogeochemical pathways involved in their production.The lake’s anoxic deep waters contain high concentrations of sulfate (12–16 mmol L 1 ) and sulfide (0.12 lmol L 1 to1.5 mmol L 1 ) with relatively low VOSC concentrations, ranging from 0.1 nmol L to 2.8 lmol L 1 . Sulfur isotope measure-ments of combined volatile Organic Sulfur Compounds demonstrate that VOSC species are formed primarily from reducedSulfur (H 2 S/HS ) and zero-valent Sulfur (ZVS), with little input from sulfate. Thedata support a role of a combination ofbiological and abiotic processes in formation of carbon–Sulfur bonds between reactive Sulfur species and methyl groups oflignin components. These processes are responsible for very fast turnover of VOSC species, maintaining their low levels inFGL. No dimethylsulfoniopropionate (DMSP) was detected by Electrospray Ionization Mass Spectrometry (ESI-MS) inthe lake water column or in planktonic extracts. These observations indicate a pathway distinct from oceanic and coastal mar-ine environments, where dimethylsulfide (DMS) and other VOSC species are principally produced via the breakdown ofDMSP by plankton species. 2013 Elsevier Ltd. All rights reserved.1. INTRODUCTIONThe use of stable isotopes to understand the biogeo-chemical cycling of Sulfur in oceanic (Rees et al., 1978;Jorgensen et al., 2004; Bo¨ttcher et al., 2006), freshwater(Fry, 1986; Canfield et al., 2010; Zerkle et al., 2010), andterrestrial systems (Goldhaber and Kaplan, 1980; Habichtand Canfield, 2001) has focused mostly on the dynamicsof inOrganic sulfate, sulfide and their intermediate species.Few studies (e.g., Amrani et al., 2009; Oduro et al., 2011)have examined Organic Sulfur Compounds, such as dimeth-ylsulfide (DMS; CH
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Multiple Sulfur isotope analysis of volatile Organic Sulfur Compounds and their sulfonium precursors in coastal marine environments
Marine Chemistry, 2011Co-Authors: Harry Oduro, Alexey Kamyshny, Weifu Guo, James FarquharAbstract:Abstract Volatile methylated Sulfur Compounds emitted from terrestrial and aquatic ecosystems play a significant role in the global Sulfur cycle, yet no satisfactory methods are available to trace their source and transformation in natural systems. Here we present a method for quantification and multiple Sulfur isotopic analysis of a variety of volatile Sulfur species as well as their natural precursors via hydrodeSulfurization with a Raney nickel catalyst. The detection limit of this method for methanethiol (MT), dimethylsulfide (DMS), dimethyldisulfide (DMDS), and carbon disulfide (CS 2 ) is 0.2 mg of Sulfur per sample. Average recovery of ~ 95% was attained for samples containing more than 1.3 mg of these Sulfur Compounds. Triplicate to quadruplicate Sulfur isotopic analyses of reduced standard materials yield average standard deviations of 0.3‰, 0.02‰, and 0.1‰, respectively, for δ 34 S, ∆ 33 S, and ∆ 36 S. The method developed here was used for determination of Sulfur isotopic compositions of volatile Organic Sulfur Compounds (VOSCs) and their precursor dimethylsulfoniopropionoate (DMSP) in sediment cores and a C 4 plant Spartina alterniflora collected from the Delaware Great Marsh. Application of the method to these natural samples indicates that the S-isotope compositions of VOSCs and DMSP-S are similar to, but slightly 34 S-depleted (~0.6–0.9), relative to porewater sulfide. These Compounds are 34 S-enriched (~ 1.7–2.0‰) relative to the compositions of the coexisting sulfide. Both suggest a relationship between source sulfide and these Organic Sulfur Compounds.
Xu Neng-bing - One of the best experts on this subject based on the ideXlab platform.
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Determination of trace volatile Organic Sulfur Compounds in environmental air by gas chromatography and mass spectrometry coupled preconcentration techniques method
Environmental Monitoring in China, 2004Co-Authors: Xu Neng-bingAbstract:Preconcentration techniques combined gas chromatography and mass spectrometry (GC/MS) was evaluated for determination of 6 kinds of trace volatile Organic Sulfur Compounds in environmental air。Using preconcentration techniques , the range of the lowest detection limits for MSH,ESH,DMS,DES,DMDS was 2.0,1.0,1.0,1.0,0.5μg/m~3, relative standard deviations (n=6)were generly lower than 9.0%.The application of the method to determination of volatile Organic Sulfur Compounds, in real sample tested by analyzing environmental air samples,satisfactory results were obtained.
Alexey Kamyshny - One of the best experts on this subject based on the ideXlab platform.
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Quadruple Sulfur isotope constraints on the origin and cycling of volatile Organic Sulfur Compounds in a stratified sulfidic lake
Geochimica et Cosmochimica Acta, 2013Co-Authors: Harry Oduro, Alexey Kamyshny, Aubrey L. Zerkle, James FarquharAbstract:AbstractWe have quantified the major forms of volatile Organic Sulfur Compounds (VOSCs) distributed in the water column ofstratified freshwater Fayetteville Green Lake (FGL), to evaluate the biogeochemical pathways involved in their production.The lake’s anoxic deep waters contain high concentrations of sulfate (12–16 mmol L 1 ) and sulfide (0.12 lmol L 1 to1.5 mmol L 1 ) with relatively low VOSC concentrations, ranging from 0.1 nmol L to 2.8 lmol L 1 . Sulfur isotope measure-ments of combined volatile Organic Sulfur Compounds demonstrate that VOSC species are formed primarily from reducedSulfur (H 2 S/HS ) and zero-valent Sulfur (ZVS), with little input from sulfate. Thedata support a role of a combination ofbiological and abiotic processes in formation of carbon–Sulfur bonds between reactive Sulfur species and methyl groups oflignin components. These processes are responsible for very fast turnover of VOSC species, maintaining their low levels inFGL. No dimethylsulfoniopropionate (DMSP) was detected by Electrospray Ionization Mass Spectrometry (ESI-MS) inthe lake water column or in planktonic extracts. These observations indicate a pathway distinct from oceanic and coastal mar-ine environments, where dimethylsulfide (DMS) and other VOSC species are principally produced via the breakdown ofDMSP by plankton species. 2013 Elsevier Ltd. All rights reserved.1. INTRODUCTIONThe use of stable isotopes to understand the biogeo-chemical cycling of Sulfur in oceanic (Rees et al., 1978;Jorgensen et al., 2004; Bo¨ttcher et al., 2006), freshwater(Fry, 1986; Canfield et al., 2010; Zerkle et al., 2010), andterrestrial systems (Goldhaber and Kaplan, 1980; Habichtand Canfield, 2001) has focused mostly on the dynamicsof inOrganic sulfate, sulfide and their intermediate species.Few studies (e.g., Amrani et al., 2009; Oduro et al., 2011)have examined Organic Sulfur Compounds, such as dimeth-ylsulfide (DMS; CH
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Multiple Sulfur isotope analysis of volatile Organic Sulfur Compounds and their sulfonium precursors in coastal marine environments
Marine Chemistry, 2011Co-Authors: Harry Oduro, Alexey Kamyshny, Weifu Guo, James FarquharAbstract:Abstract Volatile methylated Sulfur Compounds emitted from terrestrial and aquatic ecosystems play a significant role in the global Sulfur cycle, yet no satisfactory methods are available to trace their source and transformation in natural systems. Here we present a method for quantification and multiple Sulfur isotopic analysis of a variety of volatile Sulfur species as well as their natural precursors via hydrodeSulfurization with a Raney nickel catalyst. The detection limit of this method for methanethiol (MT), dimethylsulfide (DMS), dimethyldisulfide (DMDS), and carbon disulfide (CS 2 ) is 0.2 mg of Sulfur per sample. Average recovery of ~ 95% was attained for samples containing more than 1.3 mg of these Sulfur Compounds. Triplicate to quadruplicate Sulfur isotopic analyses of reduced standard materials yield average standard deviations of 0.3‰, 0.02‰, and 0.1‰, respectively, for δ 34 S, ∆ 33 S, and ∆ 36 S. The method developed here was used for determination of Sulfur isotopic compositions of volatile Organic Sulfur Compounds (VOSCs) and their precursor dimethylsulfoniopropionoate (DMSP) in sediment cores and a C 4 plant Spartina alterniflora collected from the Delaware Great Marsh. Application of the method to these natural samples indicates that the S-isotope compositions of VOSCs and DMSP-S are similar to, but slightly 34 S-depleted (~0.6–0.9), relative to porewater sulfide. These Compounds are 34 S-enriched (~ 1.7–2.0‰) relative to the compositions of the coexisting sulfide. Both suggest a relationship between source sulfide and these Organic Sulfur Compounds.
Gaboury Benoit - One of the best experts on this subject based on the ideXlab platform.
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Volatile Organic Sulfur Compounds in a stratified lake.
Chemosphere, 2006Co-Authors: Steven E. Mylon, Gaboury BenoitAbstract:Three volatile Organic Sulfur Compounds (VOSCs), dimethyl sulfide (DMS), carbon disulfide (CS(2)), and dimethyl disulfide (DMDS), were detected in the stratified water column of a lake (Linsley Pond) in Connecticut. The Compounds DMS and DMDS appeared in both the oxic and the anoxic portions of the water column, CS(2) was primarily found in anoxic hypolimnion. Algal metabolism and/or bacterial degradation of Sulfur-containing amino acids or other Organic materials are potential sources of VOSCs in the oxic lake water. Reactions of hydrogen sulfide with Organic Compounds and microbial degradation of Organic matter may be responsible for the production of VOSCs in the anoxic lake water. The vertical distribution patterns of these three VOSCs varied from month to month in the summer, but the daily profiles obtained in one 5-day period in the summer displayed consistency. No clear diurnal pattern for any of the three VOSCs was observed. Based on observation that these VOSCs were not present in surface and near surface waters of Linsley Pond, freshwater inputs of reduced Sulfur Compounds to the atmosphere may be insignificant.