Developing bifunctional catalysts that increase both the OER and ORR kinetics and transport reactants with high efficiency is desirable. Herein, micro–meso-macroporous FeCo-N-C-X(denoted as "MFeCo-N-C-X", X...Developing bifunctional catalysts that increase both the OER and ORR kinetics and transport reactants with high efficiency is desirable. Herein, micro–meso-macroporous FeCo-N-C-X(denoted as "MFeCo-N-C-X", X represents Fe/Co molar ratio in bimetallic zeolite imidazole frameworks FeCo-ZIFs) catalysts derived from hierarchical M-FeCo-ZIFs-X was prepared. The micropores in M-FeCo-N-C-X have strong capability in O2 capture as well as dictate the nucleation and early-stage deposition of Li2O2,the mesopores provided a channel for the electrolyte wetting, and the macroporous structure promoted more available active sites when used as cathode for Li-O2 batteries. More importantly, M-Fe CoN-C-0.2 based cathode showed a high initial capacity(18,750 mAh g-1@0.1 A g-1), good rate capability(7900 m Ah g-1@0.5 A g-1), and cycle stability up to 192 cycles. Interestingly, the FeCo-N-C-0.2 without macropores suffered relatively poorer stability with only 75 cycles, although its discharge capacity was still as high as 17,200 mA h g-1(@0.1 A g-1). The excellent performance attributed to the synergistic contribution of homogeneous Fe, Co nanoparticles and N co-doping carbon frameworks with special micro–meso-macroporous structure. The results showed that hierarchical FeCo-N-C architectures are promising cathode catalysts for Li-O2 batteries.展开更多
The performance of sequencing biofilm batch reactor( SBBR) under micro-aerobic condition for aniline-contaminated wastewater treatment was investigated in this study. Dissolved oxygen( DO) and aniline concentrations w...The performance of sequencing biofilm batch reactor( SBBR) under micro-aerobic condition for aniline-contaminated wastewater treatment was investigated in this study. Dissolved oxygen( DO) and aniline concentrations were selected as the operating variables to analyze,model,and optimize the process. In order to analyze the process,5 dependent parameters,chemical oxygen demand( COD),aniline,ammonium,total nitrogen( TN),and total phosphorous( TP) removal as the process responses were studied. From the results, increase in DO concentration could promote the removal of COD,aniline,ammonium,and TN,while increase in aniline concentration has a slightly negative impact on the removal of pollutants. The optimum DO concentration was found to be 0. 4-0. 5 mg /L. The removal efficiencies for COD,aniline,ammonium,and TN at the optimum point( DO concentration0. 5 mg /L,aniline concentration 11 mg /L) were 95. 84%,100%,75. 72%,and 45. 39%,respectively. The oxidative deamination was the main degradation method for aniline under micro-aerobic condition. Simultaneously nitrification-denitrification( SND)process performed under micro-aerobic condition and about 20%-40% nitrogen was removed by SND.展开更多
Certain microRNAs(miRNAs)can function as neuroprotective factors after reperfusion/ischemia brain injury.miRNA-142-3p can participate in the occurrence and development of tumors and myocardial ischemic injury by negat...Certain microRNAs(miRNAs)can function as neuroprotective factors after reperfusion/ischemia brain injury.miRNA-142-3p can participate in the occurrence and development of tumors and myocardial ischemic injury by negatively regulating the activity of Rac1,but it remains unclear whether miRNA-142-3p also participates in cerebral ischemia/reperfusion injury.In this study,a model of oxygen-glucose deprivation/re-oxygenation in primary cortical neurons was established and the neurons were transfected with miR-142-3p agomirs or miR-142-3p antagomirs.miR-142-3p expression was down-regulated in neurons when exposed to oxygen-glucose deprivation/re-oxygenation.Over-expression of miR-142-3p using its agomir remarkably promoted cell death and apoptosis induced by oxygen-glucose deprivation/re-oxygenation and improved mitochondrial biogenesis and function,including the expression of peroxisome proliferator-activated receptor-γcoactivator-1α,mitochondrial transcription factor A,and nuclear respiratory factor 1.However,the opposite effects were produced if miR-142-3p was inhibited.Luciferase reporter assays verified that Rac Family Small GTPase 1(Rac1)was a target gene of miR-142-3p.Over-expressed miR-142-3p inhibited NOX2 activity and expression of Rac1 and Rac1-GTPase(its activated form).miR-142-3p antagomirs had opposite effects after oxygen-glucose deprivation/re-oxygenation.Our results indicate that miR-142-3p down-regulates the expression and activation of Rac1,regulates mitochondrial biogenesis and function,and inhibits oxygen-glucose deprivation damage,thus exerting a neuroprotective effect.The experiments were approved by the Committee of Experimental Animal Use and Care of Central South University,China(approval No.201703346)on March 7,2017.展开更多
基金sponsored by the National Natural Science Foundation of China(21475021 and 21427807)the Fundamental Research Funds for the Central Universities(2242017 K41023)
文摘Developing bifunctional catalysts that increase both the OER and ORR kinetics and transport reactants with high efficiency is desirable. Herein, micro–meso-macroporous FeCo-N-C-X(denoted as "MFeCo-N-C-X", X represents Fe/Co molar ratio in bimetallic zeolite imidazole frameworks FeCo-ZIFs) catalysts derived from hierarchical M-FeCo-ZIFs-X was prepared. The micropores in M-FeCo-N-C-X have strong capability in O2 capture as well as dictate the nucleation and early-stage deposition of Li2O2,the mesopores provided a channel for the electrolyte wetting, and the macroporous structure promoted more available active sites when used as cathode for Li-O2 batteries. More importantly, M-Fe CoN-C-0.2 based cathode showed a high initial capacity(18,750 mAh g-1@0.1 A g-1), good rate capability(7900 m Ah g-1@0.5 A g-1), and cycle stability up to 192 cycles. Interestingly, the FeCo-N-C-0.2 without macropores suffered relatively poorer stability with only 75 cycles, although its discharge capacity was still as high as 17,200 mA h g-1(@0.1 A g-1). The excellent performance attributed to the synergistic contribution of homogeneous Fe, Co nanoparticles and N co-doping carbon frameworks with special micro–meso-macroporous structure. The results showed that hierarchical FeCo-N-C architectures are promising cathode catalysts for Li-O2 batteries.
基金National Major Water Project of China(No.2013ZX07201007)State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,China(No 3012DX06)
文摘The performance of sequencing biofilm batch reactor( SBBR) under micro-aerobic condition for aniline-contaminated wastewater treatment was investigated in this study. Dissolved oxygen( DO) and aniline concentrations were selected as the operating variables to analyze,model,and optimize the process. In order to analyze the process,5 dependent parameters,chemical oxygen demand( COD),aniline,ammonium,total nitrogen( TN),and total phosphorous( TP) removal as the process responses were studied. From the results, increase in DO concentration could promote the removal of COD,aniline,ammonium,and TN,while increase in aniline concentration has a slightly negative impact on the removal of pollutants. The optimum DO concentration was found to be 0. 4-0. 5 mg /L. The removal efficiencies for COD,aniline,ammonium,and TN at the optimum point( DO concentration0. 5 mg /L,aniline concentration 11 mg /L) were 95. 84%,100%,75. 72%,and 45. 39%,respectively. The oxidative deamination was the main degradation method for aniline under micro-aerobic condition. Simultaneously nitrification-denitrification( SND)process performed under micro-aerobic condition and about 20%-40% nitrogen was removed by SND.
基金supported by the National Natural Science Foundation of China,No.81771422(to ZY)
文摘Certain microRNAs(miRNAs)can function as neuroprotective factors after reperfusion/ischemia brain injury.miRNA-142-3p can participate in the occurrence and development of tumors and myocardial ischemic injury by negatively regulating the activity of Rac1,but it remains unclear whether miRNA-142-3p also participates in cerebral ischemia/reperfusion injury.In this study,a model of oxygen-glucose deprivation/re-oxygenation in primary cortical neurons was established and the neurons were transfected with miR-142-3p agomirs or miR-142-3p antagomirs.miR-142-3p expression was down-regulated in neurons when exposed to oxygen-glucose deprivation/re-oxygenation.Over-expression of miR-142-3p using its agomir remarkably promoted cell death and apoptosis induced by oxygen-glucose deprivation/re-oxygenation and improved mitochondrial biogenesis and function,including the expression of peroxisome proliferator-activated receptor-γcoactivator-1α,mitochondrial transcription factor A,and nuclear respiratory factor 1.However,the opposite effects were produced if miR-142-3p was inhibited.Luciferase reporter assays verified that Rac Family Small GTPase 1(Rac1)was a target gene of miR-142-3p.Over-expressed miR-142-3p inhibited NOX2 activity and expression of Rac1 and Rac1-GTPase(its activated form).miR-142-3p antagomirs had opposite effects after oxygen-glucose deprivation/re-oxygenation.Our results indicate that miR-142-3p down-regulates the expression and activation of Rac1,regulates mitochondrial biogenesis and function,and inhibits oxygen-glucose deprivation damage,thus exerting a neuroprotective effect.The experiments were approved by the Committee of Experimental Animal Use and Care of Central South University,China(approval No.201703346)on March 7,2017.
