Indium-based oxides are promising electrocatalysts for producing formate via CO_(2) reduction reaction,in which*OCHO is considered the key ***,we identified that the*COOH pathway could be preferential to produce forma...
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Indium-based oxides are promising electrocatalysts for producing formate via CO_(2) reduction reaction,in which*OCHO is considered the key ***,we identified that the*COOH pathway could be preferential to produce formate on In_(2)O_(3)of In/In_(2)O_(3) heterojunction due to the synergistic effect of oxygen species and ***,*CO_(2) and *COOH were observed on In_(2)O_(3) and related to formate production by in situ Raman *** theoretical calculations further demonstrated that the energy barrier of the*COOH formation on In_(2)O_(3) was decreased in the presence of oxygen vacancy,similar to or lower than that of the*OCHO formation on the In *** a result,a formate selectivity of over 90%was obtained on prepared In/In_(2)O_(3) heterojunction with 343±7mAcm^(-2) partial current ***,when using a Si-based photovoltaic as an energy supplier,10.11%solar-to-fuel energy efficiency was achieved.
Researches on solids mixing and segregation are of great significance for the operation and design of fluidized bed *** this paper,the local and global mixing and segregation characteristics of binary mixtures were in...
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Researches on solids mixing and segregation are of great significance for the operation and design of fluidized bed *** this paper,the local and global mixing and segregation characteristics of binary mixtures were investigated in a gas–solid fluidized bed by computational fluid dynamics-discrete element method(CFD-DEM)coupled approach.A methodology based on solids mixing entropy was developed to quantitatively calculate the mixing degree and time of the *** mixing curves of global mixing entropy were acquired,and the distribution maps of local mixing entropy and mixing time were also *** comparing different operating conditions,the effects of superficial gas velocity,particle density ratio and size ratio on mixing/segregation behavior were *** showed that for the partial mixing state,the fluidized bed can be divided into three parts along the bed height:complete segregation area,transition area and stable mixing *** areas showed different mixing/segregation *** gas velocity promoted the local and global mixing of binary *** increase in particle density ratio and size ratio enlarged the complete segregation area,reduced the mixing degree and increased the mixing time in the stable mixing area.
A fan-stirred combustion chamber is developed for spherically expanding flames,with P and T up to 10 bar and 473 K,*** characteristics are estimated using particle image velocimetry(PIV)at different initial pressures(...
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A fan-stirred combustion chamber is developed for spherically expanding flames,with P and T up to 10 bar and 473 K,*** characteristics are estimated using particle image velocimetry(PIV)at different initial pressures(P=0.5-5 bar),fan frequencies(ω=0-2000 r/min),and impeller diameters(D=100 and 114 mm).The flame propagation of methanol/air is investigated at different turbulence intensities(u′=0-1.77 m/s)and equivalence ratios(f=0.7-1.5).The results show that u′is independent of P and proportional toω,which can be up to 3.5 m/s at 2000 r/min.L_(T)is independent of P and performs a power regression withω*** turbulent field is homogeneous and isotropic in the central region of the chamber while the inertial subrange of spatial energy spectrum is more collapsed to-5/3 law at a high Re_(T).Compared to laminar expanding flames,the morphology of turbulent expanding flames is wrinkled and the wrinkles will be finer with the growth of turbulence intensity,consistent with the decline of the Taylor scale and the Kolmogorov *** determined S_(L)in the present study is in good agreement with that of previous *** S_(L)and S_(T)of methanol/air have a non-monotonic trend with f while peak S_(T)is shifted to the richer side compared to S_(L).This indicates that the newly built turbulent combustion chamber is reliable for further experimental study.
Cold-end systems are heat sinks of thermal power cycles,which have an essential effect on the overall performance of thermal power *** enhance the efficiency of thermal power plants,multi-pressure condensers have been...
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Cold-end systems are heat sinks of thermal power cycles,which have an essential effect on the overall performance of thermal power *** enhance the efficiency of thermal power plants,multi-pressure condensers have been applied in some large-capacity thermal power ***,little attention has been paid to the optimization of the cold-end system with multi-pressure condensers which have multiple parameters to be ***,the design optimization methods of coldend systems with single-and multi-pressure condensers are developed based on the entropy generation rate,and the genetic algorithm(GA)is used to optimize multiple *** parameters,including heat transfer area of multi-pressure condensers,steam distribution in condensers,and cooling water mass flow rate,are optimized while considering detailed entropy generation rate of the cold-end *** results show that the entropy generation rate of the multi-pressure cold-end system is less than that of the single-pressure cold-end system when the total condenser area is ***,the economic performance can be improved with the adoption of the multi-pressure cold-end *** compared with the single-pressure cold-end system,the excess revenues gained by using dual-and quadruplepressure cold-end systems are 575 and 580 k$/a,respectively.
Machine learning combined with density functional theory(DFT)enables rapid exploration of catalyst descriptors space such as adsorption energy,facilitating rapid and effective catalyst ***,there is still a lack of mod...
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Machine learning combined with density functional theory(DFT)enables rapid exploration of catalyst descriptors space such as adsorption energy,facilitating rapid and effective catalyst ***,there is still a lack of models for predicting adsorption energies on oxides,due to the complexity of elemental species and the ambiguous coordination *** work proposes an active learning workflow(LeNN)founded on local electronic transfer features(e)and the principle of coordinate rotation *** accurately characterizing the electron transfer to adsorption site atoms and their surrounding geometric structures,LeNN mitigates abrupt feature changes due to different element types and clarifies coordination *** a result,it enables the prediction of^(*)H adsorption energy on binary oxide surfaces with a mean absolute error(MAE)below 0.18 ***,we incorporate local coverage(θ_(l))and leverage neutral network ensemble to establish an active learning workflow,attaining a prediction MAE below 0.2 eV for 5419 multi-^(*)H adsorption *** findings validate the universality and capability of the proposed features in predicting^(*)H adsorption energy on binary oxide surfaces.
Supercritical water(SCW)fluidized bed reactors convert biomass to fuels without pollutants *** this work,experimental studies were carried out to investigate voidage distribution in an SCW fu-idized bed by capacitance...
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Supercritical water(SCW)fluidized bed reactors convert biomass to fuels without pollutants *** this work,experimental studies were carried out to investigate voidage distribution in an SCW fu-idized bed by capacitance *** sands with different particle sizes were fluidized by SCW under system pressure of 20-27 MPa and temperature of 410-570℃.The effect of operation conditions on voidage distributions of the emulsion phase(*** voidage and probability density)is discussed.A predicting correlation between voidage and superficial velocity in emulsion phase is *** relative error of the correlation is within+25%.These research results provide useful guidance for the optimization of supercritical water gasification technology.
Due to increasingly severe environmental and climate concerns currently, renewable energy is highly penetrated around the world. However, given the intermittency and instability of renewable energy, coal-fired generat...
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To achieve the net-zero emissions targets, the global share of renewable energy is rapidly increasing. The high penetration of intermittent and variable renewable power necessitates that coal-fired power plants enhanc...
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With the increasing penetration of renewable power, flexible power sources are urgently required by the power grid to balance the supply and demand sides. Therefore, the operational flexibility of subcritical coal-fir...
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Lithium-gas batteries(LGBs)have garnered significant attention due to their impressive high-energy densities and unique gas conversion ***,the practical application of LGBs faces substantial challenges,including slugg...
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Lithium-gas batteries(LGBs)have garnered significant attention due to their impressive high-energy densities and unique gas conversion ***,the practical application of LGBs faces substantial challenges,including sluggish gas conversion kinetics inducing in low-rate performance and high overpotential,along with limited electrochemical reversibility leading to poor cycle *** imperative task is to develop gas electrodes with remarkable catalytic activity,abundant active sites,and exceptional electrochemical ***,a versatile and well-established technique for fabricating fibrous nanomaterials,has been extensively explored in LGB *** this work,we emphasize the critical structure-property for ideal gas electrodes and summarize the advancement of employing electrospun nanofibers(NFs)for performance enhancement in *** elucidating the fundamental principles of LGBs and the electrospinning technique,we focus on the systematic design of electrospun NF-based gas electrodes regarding optimal structural fabrication,catalyst handling and activation,and catalytic site optimization,as well as considerations for large-scale *** demonstrated principles and regulations for electrode design are expected to inspire broad applications in catalyst-based energy applications.
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