Dissolved oxygen(DO)and apparent oxygen utilization(AOU)are crucial parameters for investigating marine ecosystem evolution and the marine environment.In this study,DO and AOU data were obtained and their spatial dist...Dissolved oxygen(DO)and apparent oxygen utilization(AOU)are crucial parameters for investigating marine ecosystem evolution and the marine environment.In this study,DO and AOU data were obtained and their spatial distribution characteristics were explored in the Cosmonaut Sea and Amundsen Sea in austral summer 2021.The standard deviation range of DO parallel samples was<0.1–3.7μmol·L–1,which met the accuracy requirements of the survey method.The DO concentration decreased sharply with water depth in the photic zone and increased slowly to the bottom.AOU in the surface layer of the two seas was significantly negatively correlated with chlorophyll a(p<0.01),and AOU was significantly lower in the south Cosmonaut Sea than in the north Cosmonaut Sea and Amundsen Sea(p<0.01).In austral summer,AOU was as low as<130μmol·L–1 in the nearshore Cosmonaut Sea with thicker Antarctic Surface Water down to ca.500 m.In early winter,AOU was lower than 50μmol·L–1 in the north Amundsen Sea in subsurface water(75–150 m).The unmodified Circumpolar Deep Water with high AOU(>160μmol·L–1)could surge up to ca.150–200 m in both seas,with stronger intrusion in the Amundsen Sea.The AOU in bottom water was significantly lower(p<0.01)in the Cosmonaut Sea(118.9±11.8μmol·L–1)than the Amundsen Sea(141.7±7.4μmol·L–1),indicating the stable existence of fresh oxygen-rich Antarctic Bottom Water in the Cosmonaut Sea.展开更多
Dissolved oxygen(DO)and apparent oxygen utilization(AOU)are essential parameters for evaluating the impact of climate change on marine ecosystems.In this study,we utilized data on DO and AOU collected from the Amundse...Dissolved oxygen(DO)and apparent oxygen utilization(AOU)are essential parameters for evaluating the impact of climate change on marine ecosystems.In this study,we utilized data on DO and AOU collected from the Amundsen Sea(western Antarctic)and the Cosmonaut Sea(eastern Antarctic)during the 38th Chinese National Antarctic Research Expedition,along with chlorophyll a(Chl a)data,to analyze the impact of primary production and the spatial distribution and structural features of water masses in these regions.The findings show that the standard deviation range of parallel DO samples is between 0.1 and 3.9μmol·L^(-1),meeting the precision criteria of the survey method.AOU values lower than 0.0μmol·L^(-1) were commonly observed in the surface waters of both regions,with the highest incidence in the polynya of Amundsen Sea,indicating a strong influence of high primary production.The Cosmonaut Sea exhibited the highest AOU values(higher than 160.0μmol·L^(-1))in the 75-500 m layer,while AOU value in the Amundsen Sea did not exceed 160.0μmol·L^(-1),suggesting potential upwelling of Circumpolar Deep Water to 100 m in the Cosmonaut Sea with minimal changes in its properties,whereas significant changes were noted in the properties of upwelling modified Circumpolar Deep Water in the Amundsen Sea.AOU values lower than 125.0μmol·L^(-1)were detected in the near-bottom waters of the Cosmonaut Sea,indicating the presence of Antarctic Bottom Water.展开更多
The types of aeration equipment currently used and the problems existing in their use are discussed. The working principle, technical performance and application effect of the new aeration equipment are described. It ...The types of aeration equipment currently used and the problems existing in their use are discussed. The working principle, technical performance and application effect of the new aeration equipment are described. It has certain guiding significance for selecting aeration equipment for sewage treatment, improving efficiency, saving energy and reducing consumption.展开更多
Chemical looping dry reforming（CLDR） is an innovative technology for CO2 utilization using the chemical looping principle.The CLDR process consists of three stages,i.e.CH4 reduction,CO2 reforming,and air oxidation.S...Chemical looping dry reforming（CLDR） is an innovative technology for CO2 utilization using the chemical looping principle.The CLDR process consists of three stages,i.e.CH4 reduction,CO2 reforming,and air oxidation.Spinel nickel ferrite（NiFe2O4） was prepared and its multi-cycle performance as an oxygen carrier for CLDR was experimentally investigated.X-ray diffraction（XRD） and Laser Raman spectroscopy showed that a pure spinel crystalline phase（NiFe2O4） was obtained by a parallel flow co-precipitating method.NiFe2O4was reduced into Fe-Ni alloy and wustite（FexO） during the CH4 reduction process.Subsequent oxidation of the reduced oxygen carrier was performed with CO2 as an oxidant to form an intermediate state：a mixture of spinel Ni（1-x）Fe（2＋x）O4,Fe（2＋y）O4 and metallic Ni.And CO was generated in parallel during this stage.Approximate 185 mL of CO was generated for 1 g spinel NiFe2O4 in a single cycle.The intermediate oxygen carrier was fully oxidized in the air oxidation stage to form a mixture of Ni（1＋x）Fe（2-x）O4 and Fe2O3.Although the original state of oxygen carrier（NiFe2O4） was not fully regenerated and agglomeration was observed,a good recyclability was shown in 10 successive redox cycles.展开更多
Photo-catalytic oxidation of intracellular nicotinamide adenine dinucleotide(2'-phosphate)(NAD(P)H)has attracted much attention for cancer therapy.However,the general oxygen-dependent mechanism heavily depresses t...Photo-catalytic oxidation of intracellular nicotinamide adenine dinucleotide(2'-phosphate)(NAD(P)H)has attracted much attention for cancer therapy.However,the general oxygen-dependent mechanism heavily depresses the efficacy in hypoxic tumors.To solve this problem,herein platinum nanoparticles(Pt NPs)with catalase-like(CAT-like)and catalytic H_(2)evolution activities were introduced as a powerful assistant to enhance the photo-catalytic NAD(P)H oxidation of Ru1([Ru(phen)2(PIP-OCH_(3))]^(2+),phen=1,10-phenanthroline,PIP-OCH_(3)=2-(4-methoxy phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline)under hypoxic and even oxygen-free conditions.Firstly,Pt NPs can transform the original and in situ formed H_(2)O_(2)once again into O_(2)by the CAT-like activity,thus relieving tumor hypoxia and realizing cyclic utilization(at least in part)of the precious oxygen in hypoxia.Secondly,Pt NPs can also be served as H_(2)evolution catalysts while using Ru1 as the photosensitizer and NAD(P)H as the electron and proton donor.In this process,NAD(P)H is oxidized without the participation of oxygen,which can provide an effective way even under oxygen-free conditions.Via co-encapsulation of Rul and Pt NPs in bovine serum albumin(BSA)with tumor targeting ability,the resultant Ru/Pt@BSA could photo-catalyze intracellular NAD(P)H oxidation under hypoxic conditions(3%O_(2)),and exhibited an efficient and selective anticancer activity both in vitro and in vivo.Our results may provide new sights for efficient and targeted cancer treatment underhypoxic conditions.展开更多
Enhancing the electrosynthesis of hydrogen peroxide(H_(2)O_(2))(the two-electron oxygen reduction and 2e−ORR)is critical for decentralized and on-site H_(2)O_(2) production.However,the high aeration energy consumption...Enhancing the electrosynthesis of hydrogen peroxide(H_(2)O_(2))(the two-electron oxygen reduction and 2e−ORR)is critical for decentralized and on-site H_(2)O_(2) production.However,the high aeration energy consumption and serious side reactions in the 2e−ORR system have decreased its 2e−ORR performance,hindering its further application.Herein,we greatly reduced the aeration energy consumption using anode-produced O_(2) for the cathode 2e−ORR(anode-cathode coupling)and further decreased the hydrogen evolution reaction(HER)and H_(2)O_(2) electroreduction by applying pulses.A flowthrough reactor with narrow electrode gaps efficiently improves the utilization of anode-produced O_(2).It increased the effluent H_(2)O_(2) concentration by 101.22%compared to non-coupled systems.In addition,pulsed electrolysis increased the effluent H_(2)O_(2) concentration and current efficiency by 3.41 and 11.38 times,respectively.During the power-off period,the electrochemical reaction paused,whereas the O_(2) and H_(2)O_(2) diffusion continued under the concentration gradient.These processes relieve the O_(2) shortage at the cathodes to decrease the HER and alleviate H_(2)O_(2) accumulation at the cathodes,thus reducing its decomposition.Our results provide an easy and efficient way to improve H_(2)O_(2) electrosynthesis performance.展开更多
基金supported by the National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(Grant nos.IRASCC 01-01-02A,IRASCC 02-02)the National Key Research and Development Program of China(Grant no.2022YFE0136500)the National Natural Science Foundation of China(Grant no.41976228).
文摘Dissolved oxygen(DO)and apparent oxygen utilization(AOU)are crucial parameters for investigating marine ecosystem evolution and the marine environment.In this study,DO and AOU data were obtained and their spatial distribution characteristics were explored in the Cosmonaut Sea and Amundsen Sea in austral summer 2021.The standard deviation range of DO parallel samples was<0.1–3.7μmol·L–1,which met the accuracy requirements of the survey method.The DO concentration decreased sharply with water depth in the photic zone and increased slowly to the bottom.AOU in the surface layer of the two seas was significantly negatively correlated with chlorophyll a(p<0.01),and AOU was significantly lower in the south Cosmonaut Sea than in the north Cosmonaut Sea and Amundsen Sea(p<0.01).In austral summer,AOU was as low as<130μmol·L–1 in the nearshore Cosmonaut Sea with thicker Antarctic Surface Water down to ca.500 m.In early winter,AOU was lower than 50μmol·L–1 in the north Amundsen Sea in subsurface water(75–150 m).The unmodified Circumpolar Deep Water with high AOU(>160μmol·L–1)could surge up to ca.150–200 m in both seas,with stronger intrusion in the Amundsen Sea.The AOU in bottom water was significantly lower(p<0.01)in the Cosmonaut Sea(118.9±11.8μmol·L–1)than the Amundsen Sea(141.7±7.4μmol·L–1),indicating the stable existence of fresh oxygen-rich Antarctic Bottom Water in the Cosmonaut Sea.
基金supported by the Scientific Research Fund of the Second Institute of Oceanography,MNR(Grant nos.JG2211 and JG2212)the National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(Grant nos.IRASCC 01-01-02A and IRASCC 02-02)+1 种基金the National Key Research and Development Program of China(Grant no.2022YFE0136500)the National Natural Science Foundation of China(Grant no.41976228)。
文摘Dissolved oxygen(DO)and apparent oxygen utilization(AOU)are essential parameters for evaluating the impact of climate change on marine ecosystems.In this study,we utilized data on DO and AOU collected from the Amundsen Sea(western Antarctic)and the Cosmonaut Sea(eastern Antarctic)during the 38th Chinese National Antarctic Research Expedition,along with chlorophyll a(Chl a)data,to analyze the impact of primary production and the spatial distribution and structural features of water masses in these regions.The findings show that the standard deviation range of parallel DO samples is between 0.1 and 3.9μmol·L^(-1),meeting the precision criteria of the survey method.AOU values lower than 0.0μmol·L^(-1) were commonly observed in the surface waters of both regions,with the highest incidence in the polynya of Amundsen Sea,indicating a strong influence of high primary production.The Cosmonaut Sea exhibited the highest AOU values(higher than 160.0μmol·L^(-1))in the 75-500 m layer,while AOU value in the Amundsen Sea did not exceed 160.0μmol·L^(-1),suggesting potential upwelling of Circumpolar Deep Water to 100 m in the Cosmonaut Sea with minimal changes in its properties,whereas significant changes were noted in the properties of upwelling modified Circumpolar Deep Water in the Amundsen Sea.AOU values lower than 125.0μmol·L^(-1)were detected in the near-bottom waters of the Cosmonaut Sea,indicating the presence of Antarctic Bottom Water.
文摘The types of aeration equipment currently used and the problems existing in their use are discussed. The working principle, technical performance and application effect of the new aeration equipment are described. It has certain guiding significance for selecting aeration equipment for sewage treatment, improving efficiency, saving energy and reducing consumption.
基金the financial support by the National Natural Science Foundation of China(51406214 and51406208)supported by the Natural science Foundation of Guangdong Province(2015A030313719)the Science&Technology Research Project of Guangdong Province(2013B050800008)
文摘Chemical looping dry reforming（CLDR） is an innovative technology for CO2 utilization using the chemical looping principle.The CLDR process consists of three stages,i.e.CH4 reduction,CO2 reforming,and air oxidation.Spinel nickel ferrite（NiFe2O4） was prepared and its multi-cycle performance as an oxygen carrier for CLDR was experimentally investigated.X-ray diffraction（XRD） and Laser Raman spectroscopy showed that a pure spinel crystalline phase（NiFe2O4） was obtained by a parallel flow co-precipitating method.NiFe2O4was reduced into Fe-Ni alloy and wustite（FexO） during the CH4 reduction process.Subsequent oxidation of the reduced oxygen carrier was performed with CO2 as an oxidant to form an intermediate state：a mixture of spinel Ni（1-x）Fe（2＋x）O4,Fe（2＋y）O4 and metallic Ni.And CO was generated in parallel during this stage.Approximate 185 mL of CO was generated for 1 g spinel NiFe2O4 in a single cycle.The intermediate oxygen carrier was fully oxidized in the air oxidation stage to form a mixture of Ni（1＋x）Fe（2-x）O4 and Fe2O3.Although the original state of oxygen carrier（NiFe2O4） was not fully regenerated and agglomeration was observed,a good recyclability was shown in 10 successive redox cycles.
基金financially supported by Research Equipment Development Project of Chinese Academy of Sciences(No.YJKYYQ20210014).
文摘Photo-catalytic oxidation of intracellular nicotinamide adenine dinucleotide(2'-phosphate)(NAD(P)H)has attracted much attention for cancer therapy.However,the general oxygen-dependent mechanism heavily depresses the efficacy in hypoxic tumors.To solve this problem,herein platinum nanoparticles(Pt NPs)with catalase-like(CAT-like)and catalytic H_(2)evolution activities were introduced as a powerful assistant to enhance the photo-catalytic NAD(P)H oxidation of Ru1([Ru(phen)2(PIP-OCH_(3))]^(2+),phen=1,10-phenanthroline,PIP-OCH_(3)=2-(4-methoxy phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline)under hypoxic and even oxygen-free conditions.Firstly,Pt NPs can transform the original and in situ formed H_(2)O_(2)once again into O_(2)by the CAT-like activity,thus relieving tumor hypoxia and realizing cyclic utilization(at least in part)of the precious oxygen in hypoxia.Secondly,Pt NPs can also be served as H_(2)evolution catalysts while using Ru1 as the photosensitizer and NAD(P)H as the electron and proton donor.In this process,NAD(P)H is oxidized without the participation of oxygen,which can provide an effective way even under oxygen-free conditions.Via co-encapsulation of Rul and Pt NPs in bovine serum albumin(BSA)with tumor targeting ability,the resultant Ru/Pt@BSA could photo-catalyze intracellular NAD(P)H oxidation under hypoxic conditions(3%O_(2)),and exhibited an efficient and selective anticancer activity both in vitro and in vivo.Our results may provide new sights for efficient and targeted cancer treatment underhypoxic conditions.
基金National Key Research and Development Program of China(No.2022YFC3901304)the National Natural Science Foundation of China(Nos.52221004,U24A20190,and 52400101).
文摘Enhancing the electrosynthesis of hydrogen peroxide(H_(2)O_(2))(the two-electron oxygen reduction and 2e−ORR)is critical for decentralized and on-site H_(2)O_(2) production.However,the high aeration energy consumption and serious side reactions in the 2e−ORR system have decreased its 2e−ORR performance,hindering its further application.Herein,we greatly reduced the aeration energy consumption using anode-produced O_(2) for the cathode 2e−ORR(anode-cathode coupling)and further decreased the hydrogen evolution reaction(HER)and H_(2)O_(2) electroreduction by applying pulses.A flowthrough reactor with narrow electrode gaps efficiently improves the utilization of anode-produced O_(2).It increased the effluent H_(2)O_(2) concentration by 101.22%compared to non-coupled systems.In addition,pulsed electrolysis increased the effluent H_(2)O_(2) concentration and current efficiency by 3.41 and 11.38 times,respectively.During the power-off period,the electrochemical reaction paused,whereas the O_(2) and H_(2)O_(2) diffusion continued under the concentration gradient.These processes relieve the O_(2) shortage at the cathodes to decrease the HER and alleviate H_(2)O_(2) accumulation at the cathodes,thus reducing its decomposition.Our results provide an easy and efficient way to improve H_(2)O_(2) electrosynthesis performance.
