Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liqu...Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.展开更多
Kinetic parameters of the electrode reactions were measured by investigating steady-state current-potential behaviors. The Tafel slopes of cathodic and anodic processes are -0.113 8 V and -0.041 18 V, the anodic and c...Kinetic parameters of the electrode reactions were measured by investigating steady-state current-potential behaviors. The Tafel slopes of cathodic and anodic processes are -0.113 8 V and -0.041 18 V, the anodic and cathodic apparent transfer coefficients are 0.519 3 and 1.435 2, respectively, and the stoichiometric number of rate-deterrnining step is 1. The theoretical kinetics equation of electrode reaction was deduced, from which the dynamic parameters can be calculated as follows： the cathodic and anodic Tafel slopes are -0.118 V and -0.039 4 V, respectively, consisting with the experimental values, Finally, the correctness of the mechanism was further demonstrated using apparent transfer coefficient according to the electrochemical dynamic equation of multi-electron reaction.展开更多
The use of electro-osmotic chemical is an effective method to improve the clayey soil foundation.Various boundary conditions can be adopted in this method.In this work,two electrode–clay contacts,three solution condi...The use of electro-osmotic chemical is an effective method to improve the clayey soil foundation.Various boundary conditions can be adopted in this method.In this work,two electrode–clay contacts,three solution conditioners,and four anode solution supply times were used for clayey soil improvement.Based on the experimental data,electro-osmotic consolidation theory,and transport of ion theory,it is found that the electro-osmotic chemical effect of the separation of electrode–clay(E_S)is more beneficial for the transport of Ca^(2+),production of cementing material,and reduction of water content than that of electrode–clay(E_C)joining;through electrode–clay contact separation,the anode solution conditioner(NaPO3)6(E_SHMP)delayed the cementing reaction and then increased the transport of Ca^(2+)near the cathode,which increased the amount of cementing material and the electro-osmotic chemical effect;and when the anode conditioner(NaPO3)6 was used,two days of anode solution supply followed by three days cut off from the anode solution led to the highest undrained shear strength increase after the application of electro-osmotic chemical,which resolved the uneven electro-osmotic chemical effect in the E_SHMP.展开更多
It is urgent to develop low-cost but efficient oxygen reduction reaction(ORR)catalysts for the emerging clean energy devices of fuel cells based on proton exchange membrane.Herein,we report a facile method to covert t...It is urgent to develop low-cost but efficient oxygen reduction reaction(ORR)catalysts for the emerging clean energy devices of fuel cells based on proton exchange membrane.Herein,we report a facile method to covert the biomass of black fungus into an efficient ORR catalyst.The black fungus undergoes hydrothermal and pyrolysis processes to transform into carbon-based materials.The as-obtained BF-N-950 catalyst shows prominent ORR catalytic activities in both acidic and alkaline electrolytes with a half-wave potential reaching 0.77 and 0.91 V,respectively.A membrane electrolyte assembly was fabricated with the as-obtained BF-N-950 as the cathode catalyst which shows a high peak power density of255 mW cm^-2.The study shows the potential of converting conventional biomass into low-cost ORR catalyst,which is promising for the fuel cell technology.展开更多
基金the Natural Science Foundation of Guangdong Province (No. 020839).
文摘Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.
文摘Kinetic parameters of the electrode reactions were measured by investigating steady-state current-potential behaviors. The Tafel slopes of cathodic and anodic processes are -0.113 8 V and -0.041 18 V, the anodic and cathodic apparent transfer coefficients are 0.519 3 and 1.435 2, respectively, and the stoichiometric number of rate-deterrnining step is 1. The theoretical kinetics equation of electrode reaction was deduced, from which the dynamic parameters can be calculated as follows： the cathodic and anodic Tafel slopes are -0.118 V and -0.039 4 V, respectively, consisting with the experimental values, Finally, the correctness of the mechanism was further demonstrated using apparent transfer coefficient according to the electrochemical dynamic equation of multi-electron reaction.
基金Project(41902280)supported by the National Natural Science Foundation of ChinaProject(300102219105)supported by the Fundamental Research Funds for the Central Universities,China+1 种基金Project(LP1922)supported by the Open Foundation of State Key Laboratory of Coastal and Offshore Engineering,ChinaProject(XJKFJJ201805)supported by the Open Foundation of Shaanxi Key Laboratory of Safety and Durability of Concrete Structures,China。
文摘The use of electro-osmotic chemical is an effective method to improve the clayey soil foundation.Various boundary conditions can be adopted in this method.In this work,two electrode–clay contacts,three solution conditioners,and four anode solution supply times were used for clayey soil improvement.Based on the experimental data,electro-osmotic consolidation theory,and transport of ion theory,it is found that the electro-osmotic chemical effect of the separation of electrode–clay(E_S)is more beneficial for the transport of Ca^(2+),production of cementing material,and reduction of water content than that of electrode–clay(E_C)joining;through electrode–clay contact separation,the anode solution conditioner(NaPO3)6(E_SHMP)delayed the cementing reaction and then increased the transport of Ca^(2+)near the cathode,which increased the amount of cementing material and the electro-osmotic chemical effect;and when the anode conditioner(NaPO3)6 was used,two days of anode solution supply followed by three days cut off from the anode solution led to the highest undrained shear strength increase after the application of electro-osmotic chemical,which resolved the uneven electro-osmotic chemical effect in the E_SHMP.
基金financially supported by the National Key Research and Development Program of China (2017YFA0206500)the National Natural Science Foundation of China (21671014)the Fundamental Research Funds for the Central Universities (buctrc201823)
文摘It is urgent to develop low-cost but efficient oxygen reduction reaction(ORR)catalysts for the emerging clean energy devices of fuel cells based on proton exchange membrane.Herein,we report a facile method to covert the biomass of black fungus into an efficient ORR catalyst.The black fungus undergoes hydrothermal and pyrolysis processes to transform into carbon-based materials.The as-obtained BF-N-950 catalyst shows prominent ORR catalytic activities in both acidic and alkaline electrolytes with a half-wave potential reaching 0.77 and 0.91 V,respectively.A membrane electrolyte assembly was fabricated with the as-obtained BF-N-950 as the cathode catalyst which shows a high peak power density of255 mW cm^-2.The study shows the potential of converting conventional biomass into low-cost ORR catalyst,which is promising for the fuel cell technology.
