Photoelectrochemistry is a promising method for the direct conversion of sunlight into valuable chemicals by combining the functions of solar panels and electrolyzers in one technology.In most studies,semiconductor/ca...Photoelectrochemistry is a promising method for the direct conversion of sunlight into valuable chemicals by combining the functions of solar panels and electrolyzers in one technology.In most studies,semiconductor/catalyst photoelectrode assemblies are used to achieve reasonable efficiencies.At the same time,unlike in dark electrochemical processes,the role of the catalyst is not straightforward in photoelectrochemistry,where the onset potential of the redox process should be mostly determined by the flatband potential of the semiconductor.In addition,the energy of holes(i.e.,the surface potential)is independent of the applied bias;it is defined by the valence band(VB)position.In this study,we compared PdAu,Au,and Ni on Si photoanodes in the photoelectrochemical(PEC)oxidation of glycerol at record high current densities(>180 mA cm^(‒2)),coupled to H_(2) evolution at the cathode.We successfully decreased the energy requirement(i.e.,the cell voltage)of the paired conversion of glycerol and water by 0.7 V by exchanging the widely studied Ni catalyst with PdAu.The catalyst choice also dictates the product distribution,resulting mainly in C3 products on PdAu,glycolate(C2 product)on Au,and formate(C1 product)on Ni,without complete mineralization of glycerol(CO_(2) formation)that is difficult to rule out in dark electrochemical processes(as demonstrated by comparative measurements).Finally,we achieved a bias‐free(standalone)operation with PdAu/Si and Au/Si photoanodes by combining the PEC oxidation of glycerol with oxygen reduction reaction(ORR).展开更多
We present an overview of some recent developments in the area of mathematical modeling of maintenance decisions for multi-unit systems. The emphasis is on three main groups of multicomponent maintenance optimization ...We present an overview of some recent developments in the area of mathematical modeling of maintenance decisions for multi-unit systems. The emphasis is on three main groups of multicomponent maintenance optimization models： the block replacement models, group maintenance models, and opportunistic maintenance models. Moreover, an example of a two-unit system maintenance process is provided in order to compare various maintenance policies.展开更多
On April 3, 39 teachers and students from the Beijing Institute of Technology (BIT)were trapped on the MaoerMountain in Fangshan District,a suburban area in Beijing. Morethan 300 persons,
In this paper a new theory referred to as the decrease-radix design （DRD） is proposed, which is found in the research of logic units of ternary （tri-valued） optical computer. Based on the theory proposed, the prin...In this paper a new theory referred to as the decrease-radix design （DRD） is proposed, which is found in the research of logic units of ternary （tri-valued） optical computer. Based on the theory proposed, the principles and the regulations of the DRD for making operation units of multi-valued operation with carrying/borrowing free are also presented. The research work has come to the following important conclusion： let D be a special state contained in n physical informative states, then one may figure out any multi-valued processors within n^（n×n） carrying/borrowing free n-valued units by the composition some of n×n×（n-1） simplest basic operating units according to the regulations of DRD proposed in this paper. The detailed systematic way of our design regulations is highlighted step by step in the paper with an example of design of a tri-valued logic optical operating unit. The real architecture, the procedure, and the experimental results of our sample in tri-valued logic operating unit are given. Finally, a re-constructible model of ternary logical optical processor is introduced. The theory proposed in the paper has laid down a solid foundation for the design of re-constructible carrying/borrowing free operating units in ternary optical computers and can be widely used as the designing reference in a variety of multi-valued logic operating units.展开更多
基金funding under the European Union's Horizon Europe research and innovation program from the European Research Council(ERC,Grant Agreement No.101043617)(C.J.).Project No.RRF‐2.3.1‐21‐2022‐00009titled National Laboratory for Renewable Energy,was implemented with the support provided by the Recovery and Resilience Facility of the European Union within the framework of the Program Széchenyi Plan Plus(C.J.)support from MICIU/AEI/10.13039/501100011033/(PID2020-116093RB−C41 and PID2023‐152771OB‐I00).European Innovation Council(EIC)(101071010).
文摘Photoelectrochemistry is a promising method for the direct conversion of sunlight into valuable chemicals by combining the functions of solar panels and electrolyzers in one technology.In most studies,semiconductor/catalyst photoelectrode assemblies are used to achieve reasonable efficiencies.At the same time,unlike in dark electrochemical processes,the role of the catalyst is not straightforward in photoelectrochemistry,where the onset potential of the redox process should be mostly determined by the flatband potential of the semiconductor.In addition,the energy of holes(i.e.,the surface potential)is independent of the applied bias;it is defined by the valence band(VB)position.In this study,we compared PdAu,Au,and Ni on Si photoanodes in the photoelectrochemical(PEC)oxidation of glycerol at record high current densities(>180 mA cm^(‒2)),coupled to H_(2) evolution at the cathode.We successfully decreased the energy requirement(i.e.,the cell voltage)of the paired conversion of glycerol and water by 0.7 V by exchanging the widely studied Ni catalyst with PdAu.The catalyst choice also dictates the product distribution,resulting mainly in C3 products on PdAu,glycolate(C2 product)on Au,and formate(C1 product)on Ni,without complete mineralization of glycerol(CO_(2) formation)that is difficult to rule out in dark electrochemical processes(as demonstrated by comparative measurements).Finally,we achieved a bias‐free(standalone)operation with PdAu/Si and Au/Si photoanodes by combining the PEC oxidation of glycerol with oxygen reduction reaction(ORR).
文摘We present an overview of some recent developments in the area of mathematical modeling of maintenance decisions for multi-unit systems. The emphasis is on three main groups of multicomponent maintenance optimization models： the block replacement models, group maintenance models, and opportunistic maintenance models. Moreover, an example of a two-unit system maintenance process is provided in order to compare various maintenance policies.
文摘On April 3, 39 teachers and students from the Beijing Institute of Technology (BIT)were trapped on the MaoerMountain in Fangshan District,a suburban area in Beijing. Morethan 300 persons,
基金the National Natural Science Foundation of China (Grant No.60473008)Science & Technology Foundation of University in Shanghai (Grant No.04AB38)+1 种基金Shanghai Leading Academic Discipline Project (Grant No.J50103)the Doctorate Foundation of Shanghai University
文摘In this paper a new theory referred to as the decrease-radix design （DRD） is proposed, which is found in the research of logic units of ternary （tri-valued） optical computer. Based on the theory proposed, the principles and the regulations of the DRD for making operation units of multi-valued operation with carrying/borrowing free are also presented. The research work has come to the following important conclusion： let D be a special state contained in n physical informative states, then one may figure out any multi-valued processors within n^（n×n） carrying/borrowing free n-valued units by the composition some of n×n×（n-1） simplest basic operating units according to the regulations of DRD proposed in this paper. The detailed systematic way of our design regulations is highlighted step by step in the paper with an example of design of a tri-valued logic optical operating unit. The real architecture, the procedure, and the experimental results of our sample in tri-valued logic operating unit are given. Finally, a re-constructible model of ternary logical optical processor is introduced. The theory proposed in the paper has laid down a solid foundation for the design of re-constructible carrying/borrowing free operating units in ternary optical computers and can be widely used as the designing reference in a variety of multi-valued logic operating units.
