0 INTRODUCTION Sedimentary exhalative(SEDEX)lead-zinc deposit was traditionally considered as a result of submarine hydrothermal exhalation,including exhalative plume and brine pool models(Izanloo et al.,2022;Spinks e...0 INTRODUCTION Sedimentary exhalative(SEDEX)lead-zinc deposit was traditionally considered as a result of submarine hydrothermal exhalation,including exhalative plume and brine pool models(Izanloo et al.,2022;Spinks et al.,2021;Maghfouri et al.,2020;Sangster,2020,2018;Huang et al.,2019;Rajabi et al.,2015;Goodfellow and Lydon,2007;Large et al.,2005,2001;Peng et al.,2000;Goodfellow et al.,1993;Figures 1a,1b).However,recognition of mineralization as subseafloor hydrothermal replacement in a few SEDEX deposits has challenged the traditional consideration(Magnall et al.,2023,2021,2020a,b;Hayward et al.,2021;Figure 1c).Researchers come to believe that subseafloor replacement rather than submarine exhalation is a dominant process for SEDEX mineralization,but this needs to be examined through more case studies.展开更多
With a large amount of domestic sewage and industrial wastewater discharged into the water bodies,sulfur-containing organicmatter inwastewater produced volatile organic sulfide,such as dimethyl trisulfide(DMTS)through...With a large amount of domestic sewage and industrial wastewater discharged into the water bodies,sulfur-containing organicmatter inwastewater produced volatile organic sulfide,such as dimethyl trisulfide(DMTS)throughmicroorganisms,caused the potential danger of drinking water safety and human health.At present,there is still a lack of technology on the removal of DMTS.In this study,the ultraviolet/peroxymonosulfate(UV/PMS)advanced oxidation processes was used to explore the degradation of DMTS.More than 90%of DMTS(30μg/L)was removed under the conditions of the concentration ratio of DMTS to PMS was 3:40,the temperature(T)was 25±2℃,and 10 min of irradiation by a 200 W mercury lamp(365 nm).The kinetics rate constant k of DMTS reacting with hydroxyl radical(HO·)was determined to be 0.2477 min^(−1).Mn^(2+),Cu^(2+)and NO_(3)^(-)promoted the degradation of DMTS,whereas humic acid and Cl-in high concentrations inhibited the degradation process.Gas chromatography-mass spectrometry was used to analyze the degradation products and the degradation intermediates were dimethyl disulfide and methanethiol.Density functional theory was used to predict the possible degradation mechanism according to the frontier orbital theory and the bond breaking mechanism of organic compounds.The results showed that the S–S,C–S and C–H bonds in DMTS molecular structure were prone to fracture in the presence of free radicals,resulting in the formation of alkyl radicals and sulfur-containing radicals,which randomly combined to generate a variety of degradation products.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42372115,92155305,92055314)the Innovation Capability Support Program of Shaanxi Province(No.2022KJXX-91)+2 种基金the Basic Research Program of Natural Science in Shaanxi Province(No.2023-JC-QN-0281)the International Geoscience Program(NoIGCP-741)China Geological Survey(No.DD20201159).
文摘0 INTRODUCTION Sedimentary exhalative(SEDEX)lead-zinc deposit was traditionally considered as a result of submarine hydrothermal exhalation,including exhalative plume and brine pool models(Izanloo et al.,2022;Spinks et al.,2021;Maghfouri et al.,2020;Sangster,2020,2018;Huang et al.,2019;Rajabi et al.,2015;Goodfellow and Lydon,2007;Large et al.,2005,2001;Peng et al.,2000;Goodfellow et al.,1993;Figures 1a,1b).However,recognition of mineralization as subseafloor hydrothermal replacement in a few SEDEX deposits has challenged the traditional consideration(Magnall et al.,2023,2021,2020a,b;Hayward et al.,2021;Figure 1c).Researchers come to believe that subseafloor replacement rather than submarine exhalation is a dominant process for SEDEX mineralization,but this needs to be examined through more case studies.
基金supported by Central Leading Local Science and Technology Development Fund Project of Shandong Province(No.YDZX20203700001642)JinanWater Science and Technology Project(No.JNSWKJ202108)Natural Science Foundation of Shandong Province(No.ZR2019QEE022).
文摘With a large amount of domestic sewage and industrial wastewater discharged into the water bodies,sulfur-containing organicmatter inwastewater produced volatile organic sulfide,such as dimethyl trisulfide(DMTS)throughmicroorganisms,caused the potential danger of drinking water safety and human health.At present,there is still a lack of technology on the removal of DMTS.In this study,the ultraviolet/peroxymonosulfate(UV/PMS)advanced oxidation processes was used to explore the degradation of DMTS.More than 90%of DMTS(30μg/L)was removed under the conditions of the concentration ratio of DMTS to PMS was 3:40,the temperature(T)was 25±2℃,and 10 min of irradiation by a 200 W mercury lamp(365 nm).The kinetics rate constant k of DMTS reacting with hydroxyl radical(HO·)was determined to be 0.2477 min^(−1).Mn^(2+),Cu^(2+)and NO_(3)^(-)promoted the degradation of DMTS,whereas humic acid and Cl-in high concentrations inhibited the degradation process.Gas chromatography-mass spectrometry was used to analyze the degradation products and the degradation intermediates were dimethyl disulfide and methanethiol.Density functional theory was used to predict the possible degradation mechanism according to the frontier orbital theory and the bond breaking mechanism of organic compounds.The results showed that the S–S,C–S and C–H bonds in DMTS molecular structure were prone to fracture in the presence of free radicals,resulting in the formation of alkyl radicals and sulfur-containing radicals,which randomly combined to generate a variety of degradation products.
