Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries(LSBs)because of their successful implementation in commercial Li-ion batteries.The low-polysulfide-solubility ...Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries(LSBs)because of their successful implementation in commercial Li-ion batteries.The low-polysulfide-solubility feature of some carbonate solvents also makes them very promising for overcoming the shuttle effects of LSBs.However,regular sulfur electrodes experience undesired electrochemical mechanisms in carbonate electrolytes due to side reactions.In this study,we report a catalytic redox mechanism of sulfur in propylene carbonate(PC)electrolyte based on a compari-son study.The catalytic mechanism is characterized by the interactions between polysulfides and dual N/O functional groups on the host carbon,which largely prevents side reactions between pol-ysulfides and the carbonate electrolyte.Such a mechanism coupled with the low-polysulfide-solubility feature leads to stable cycling of LSBs in PC electrolyte.Favorable dual N/O functional groups are identified via a density functional theory study.This work provides an alternative route for enabling LSBs in carbonate electrolytes.展开更多
The response of phytoplankton and its satellite bacteria to various concentrations(0.01%-10%v/v)of ethanol is studied.To elucidate the effect of ethanol,single-strains of phytoplankton(SSP)culture,pure strains of sate...The response of phytoplankton and its satellite bacteria to various concentrations(0.01%-10%v/v)of ethanol is studied.To elucidate the effect of ethanol,single-strains of phytoplankton(SSP)culture,pure strains of satellite bacteria isolated from nonaxenic SSP cultures,and Escherichia coli were screened.Results indicate that ethanol could promote the growth and photo synthetic efficiency(F_(v)/F_(m))of S SP at 0.01%and the growth of satellite bacteria at 0.01%-1%.Nevertheless,ethanol inhibited the growth and F_(v)/F_(m)of SSP at 0.1%-1%,and killed bacteria and SSP at 10% concentration.Further investigation on a satellite bacterium(Mameliella alba)revealed that ethanol promotes growth by serving as a growth stimulant rather than a metabolic carbon source.The 16 S rRNA gene amplicon indicated that all nonaxenic S SP cultures harbor distinct satellite bacteria communities where the SSP culture of Skeletonema costatum,Phaeodactylum tricornutum,and Dunaliella bardawil were dominated by bacteria genera of Marivita(~80%),Dinoroseobacter(~47%),and Halomonas(~87%),respectively,indicating that every SSP cultures have their own distinct satellite bacterial community.The bacteria family Rhodobacteraceae was dominant in the two marine diatoms,whereas Halomonadaceae was dominant in the saline green microalga.Compared to their respective controls,the supply of 0.5% ethanol to SSP cultures promoted the growth of the satellite bacteria but did not cause a significant difference in species composition of satellite bacteria.Therefore,a low concentration of ethanol can promote the growth of bacteria in a non-selective way.This study enriched our knowledge about the effect of ethanol on aquatic microbes and provided a baseline for basic and applied biotechnological re search in the aquatic environment in the future.展开更多
Water-borne pathogenic bacteria are always the top priority to be removed through disinfection process in water treatment due to their threat to human health. It was necessary to develop novel disinfection methods sin...Water-borne pathogenic bacteria are always the top priority to be removed through disinfection process in water treatment due to their threat to human health. It was necessary to develop novel disinfection methods since the conventional chlorine disinfection was inefficient in inactivating chlorine-resistant bacteria, inducing the viable but non-culturable(VBNC) bacteria and forming disinfection by-products(DBPs). In this study, the inactivation of four model strains including Gram-negative(G), Gram-positive(G) and environmental samples by atmospheric-pressure air-liquid discharge plasma(ALDP) was assessed systematically. The results showed that ALDP was superior in inactivating all of the samples compared with chlorination. During 10 min ALDP treatment, the Gbacteria were completely inactivated, and the Gone was inactivated by more than 4.61 logs. The inactivation of bacteria from a campus lake and a wastewater treatment plant effluent exceeded 99.82% and 97.78%, respectively. For G-bacteria, ALDP resulted in a much lower(10~2~10~3 times) levels of VBNC cells than chlorination. ALDP could effectively remove the chlorine-resistant bacteria. More than 96.41% of the intracellular DNA and 99.99% of the extracellular DNA were removed, whereas it was only 56.35% and 12.82% for chlorination. ALDP had a stronger ability to destroy cell structure than chlorination, presumably due to the existence of ROS( ·OH, ~1Oand O). GC-MS analysis showed that ALDP produced less DBPs than chlorination. These findings provided new insights for the application of discharge plasma in water disinfection, which could be complemental or alternative to the conventional disinfection methods.展开更多
文摘Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries(LSBs)because of their successful implementation in commercial Li-ion batteries.The low-polysulfide-solubility feature of some carbonate solvents also makes them very promising for overcoming the shuttle effects of LSBs.However,regular sulfur electrodes experience undesired electrochemical mechanisms in carbonate electrolytes due to side reactions.In this study,we report a catalytic redox mechanism of sulfur in propylene carbonate(PC)electrolyte based on a compari-son study.The catalytic mechanism is characterized by the interactions between polysulfides and dual N/O functional groups on the host carbon,which largely prevents side reactions between pol-ysulfides and the carbonate electrolyte.Such a mechanism coupled with the low-polysulfide-solubility feature leads to stable cycling of LSBs in PC electrolyte.Favorable dual N/O functional groups are identified via a density functional theory study.This work provides an alternative route for enabling LSBs in carbonate electrolytes.
基金Supported by the National Natural Science Foundation of China(Nos.42076114,41876146)the China Postdoctoral Science Foundation Grant(No.2018M632580)the Special Investigation Project of Scientific and Technological Fundamental Resources(No.2018FY100202)。
文摘The response of phytoplankton and its satellite bacteria to various concentrations(0.01%-10%v/v)of ethanol is studied.To elucidate the effect of ethanol,single-strains of phytoplankton(SSP)culture,pure strains of satellite bacteria isolated from nonaxenic SSP cultures,and Escherichia coli were screened.Results indicate that ethanol could promote the growth and photo synthetic efficiency(F_(v)/F_(m))of S SP at 0.01%and the growth of satellite bacteria at 0.01%-1%.Nevertheless,ethanol inhibited the growth and F_(v)/F_(m)of SSP at 0.1%-1%,and killed bacteria and SSP at 10% concentration.Further investigation on a satellite bacterium(Mameliella alba)revealed that ethanol promotes growth by serving as a growth stimulant rather than a metabolic carbon source.The 16 S rRNA gene amplicon indicated that all nonaxenic S SP cultures harbor distinct satellite bacteria communities where the SSP culture of Skeletonema costatum,Phaeodactylum tricornutum,and Dunaliella bardawil were dominated by bacteria genera of Marivita(~80%),Dinoroseobacter(~47%),and Halomonas(~87%),respectively,indicating that every SSP cultures have their own distinct satellite bacterial community.The bacteria family Rhodobacteraceae was dominant in the two marine diatoms,whereas Halomonadaceae was dominant in the saline green microalga.Compared to their respective controls,the supply of 0.5% ethanol to SSP cultures promoted the growth of the satellite bacteria but did not cause a significant difference in species composition of satellite bacteria.Therefore,a low concentration of ethanol can promote the growth of bacteria in a non-selective way.This study enriched our knowledge about the effect of ethanol on aquatic microbes and provided a baseline for basic and applied biotechnological re search in the aquatic environment in the future.
基金supported by the Natural Science Foundation of China (Nos. 41861144023 and U2005206)the Natural and Science Guiding Project of Fujian Province (No. 2019H0036)the Xiamen Municipal Bureau of Science and Technology (No. YDZX20203502000003)。
文摘Water-borne pathogenic bacteria are always the top priority to be removed through disinfection process in water treatment due to their threat to human health. It was necessary to develop novel disinfection methods since the conventional chlorine disinfection was inefficient in inactivating chlorine-resistant bacteria, inducing the viable but non-culturable(VBNC) bacteria and forming disinfection by-products(DBPs). In this study, the inactivation of four model strains including Gram-negative(G), Gram-positive(G) and environmental samples by atmospheric-pressure air-liquid discharge plasma(ALDP) was assessed systematically. The results showed that ALDP was superior in inactivating all of the samples compared with chlorination. During 10 min ALDP treatment, the Gbacteria were completely inactivated, and the Gone was inactivated by more than 4.61 logs. The inactivation of bacteria from a campus lake and a wastewater treatment plant effluent exceeded 99.82% and 97.78%, respectively. For G-bacteria, ALDP resulted in a much lower(10~2~10~3 times) levels of VBNC cells than chlorination. ALDP could effectively remove the chlorine-resistant bacteria. More than 96.41% of the intracellular DNA and 99.99% of the extracellular DNA were removed, whereas it was only 56.35% and 12.82% for chlorination. ALDP had a stronger ability to destroy cell structure than chlorination, presumably due to the existence of ROS( ·OH, ~1Oand O). GC-MS analysis showed that ALDP produced less DBPs than chlorination. These findings provided new insights for the application of discharge plasma in water disinfection, which could be complemental or alternative to the conventional disinfection methods.
