Mesoporous CeO2 particles with high surface area were synthesized using a modified evaporation-induced self assembly(EISA) method which combined citric acid as complexing agent.As-prepared powder and further thermal t...Mesoporous CeO2 particles with high surface area were synthesized using a modified evaporation-induced self assembly(EISA) method which combined citric acid as complexing agent.As-prepared powder and further thermal treatment samples were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),selected area electron diffraction(SAED),Fourier transform infrared spectrometer(FTIR),thermogravimetry and differential thermal analysis(TG-DTA),Brunauer-Emmett-Teller(BET) and Barrett-Joyner-Ha...展开更多
Soils and waters are heavily contaminated by antimony in Xikuangshan(XKS)mine area.It is widely accepted that oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechan...Soils and waters are heavily contaminated by antimony in Xikuangshan(XKS)mine area.It is widely accepted that oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechanisms for the release of Sb to the environment.Bosea sp.AS-1 is an antimonite-oxidizer isolated from the mine slag in Xikuangshan Sb mine.Whole genome sequencing revealed the presence of multiple sulfur-oxidizing genes,antimony(Sb)metabolism genes and carbon fixation genes in AS-1 s genome.We therefore hypothesized that under oxic conditions,AS-1 could mediate the oxidation of sulfide and Sb(Ⅲ)in stibnite(Sb_(2)S_(3))and lead to the release of Sb.Indeed,strain AS-1 was discovered as an autotrophic Sb(Ⅲ)-oxidizer.Antimony mobilization studies conducted with strain AS-1showed significantly enhanced mobilization of Sb,and complete oxidation of released Sb and sulfur to Sb(V)and sulfate.In addition,AS-1 induced a faster release of Sb under heterotrophic condition,and new acicular minerals might form.These findings support the hypothesis that microorganisms play an important role in the mobilization and transformation of Sb in XKS mine area and may contribute to our further understanding of the Sb biogeochemical redox cycle in natural environment.展开更多
Large amounts of gas hydrate are distributed in the northern slope of the South China Sea,which is a potential threat of methane leakage.Aerobic methane oxidation by methanotrophs,significant methane biotransformation...Large amounts of gas hydrate are distributed in the northern slope of the South China Sea,which is a potential threat of methane leakage.Aerobic methane oxidation by methanotrophs,significant methane biotransformation that occurs in sediment surface and water column,can effectively reduce atmospheric emission of hydrate-decomposed methane.To identify active aerobic methanotrophs and their methane oxidation potential in sediments from the Shenhu Area in the South China Sea,multi-day enrichment incubations were conducted in this study.The results show that the methane oxidation rates in the studied sediments were 2.03‒2.36μmol/gdw/d,which were higher than those obtained by sediment incubations from other areas in marine ecosystems.Thus the authors suspect that the methane oxidation potential of methanotrophs was relatively higher in sediments from the Shenhu Area.After the incubations family Methylococcaea(type I methanotrophs)mainly consisted of genus Methylobacter and Methylococcaea_Other were predominant with an increased proportion of 70.3%,whereas Methylocaldum decreased simultaneously in the incubated sediments.Collectively,this study may help to gain a better understanding of the methane biotransformation in the Shenhu Area.展开更多
基金supported by the National Natural Science Foundation of China (20771047)the Natural Science Foundation of Jiangsu Province (BK2008541)+1 种基金Jiangsu Graduate Student Innovation Grant (CX82Z-007Z)Jiangsu University Innovation Grant (1293000425)
文摘Mesoporous CeO2 particles with high surface area were synthesized using a modified evaporation-induced self assembly(EISA) method which combined citric acid as complexing agent.As-prepared powder and further thermal treatment samples were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),selected area electron diffraction(SAED),Fourier transform infrared spectrometer(FTIR),thermogravimetry and differential thermal analysis(TG-DTA),Brunauer-Emmett-Teller(BET) and Barrett-Joyner-Ha...
基金supported by the National Natural Science Foundation of China(Nos.42077220 and 41877320)。
文摘Soils and waters are heavily contaminated by antimony in Xikuangshan(XKS)mine area.It is widely accepted that oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechanisms for the release of Sb to the environment.Bosea sp.AS-1 is an antimonite-oxidizer isolated from the mine slag in Xikuangshan Sb mine.Whole genome sequencing revealed the presence of multiple sulfur-oxidizing genes,antimony(Sb)metabolism genes and carbon fixation genes in AS-1 s genome.We therefore hypothesized that under oxic conditions,AS-1 could mediate the oxidation of sulfide and Sb(Ⅲ)in stibnite(Sb_(2)S_(3))and lead to the release of Sb.Indeed,strain AS-1 was discovered as an autotrophic Sb(Ⅲ)-oxidizer.Antimony mobilization studies conducted with strain AS-1showed significantly enhanced mobilization of Sb,and complete oxidation of released Sb and sulfur to Sb(V)and sulfate.In addition,AS-1 induced a faster release of Sb under heterotrophic condition,and new acicular minerals might form.These findings support the hypothesis that microorganisms play an important role in the mobilization and transformation of Sb in XKS mine area and may contribute to our further understanding of the Sb biogeochemical redox cycle in natural environment.
基金jointly supported by the National Natural Science Foundation of China (42106052)Shandong Provincial Natural Science Foundation (ZR2020QD070)the project of China Geological Survey (DD20190221)。
文摘Large amounts of gas hydrate are distributed in the northern slope of the South China Sea,which is a potential threat of methane leakage.Aerobic methane oxidation by methanotrophs,significant methane biotransformation that occurs in sediment surface and water column,can effectively reduce atmospheric emission of hydrate-decomposed methane.To identify active aerobic methanotrophs and their methane oxidation potential in sediments from the Shenhu Area in the South China Sea,multi-day enrichment incubations were conducted in this study.The results show that the methane oxidation rates in the studied sediments were 2.03‒2.36μmol/gdw/d,which were higher than those obtained by sediment incubations from other areas in marine ecosystems.Thus the authors suspect that the methane oxidation potential of methanotrophs was relatively higher in sediments from the Shenhu Area.After the incubations family Methylococcaea(type I methanotrophs)mainly consisted of genus Methylobacter and Methylococcaea_Other were predominant with an increased proportion of 70.3%,whereas Methylocaldum decreased simultaneously in the incubated sediments.Collectively,this study may help to gain a better understanding of the methane biotransformation in the Shenhu Area.
