Tantalum nitride is widely considered as a promising photoanode material for its suitable band structure as well as the high theoretical conversion efficiency in solar water splitting.However,it is limited to ineffici...Tantalum nitride is widely considered as a promising photoanode material for its suitable band structure as well as the high theoretical conversion efficiency in solar water splitting.However,it is limited to inefficient photoinduced electron–hole pair separation and interfacial dynamics in the photoelectrochemical oxygen evolution reaction.Herein,multiple layers including Ti_(x)Si_(y) and NiFeCoO_(x) were fabricated based on band engineering to regulate tandem electric states for efficient transfer of energy carriers.Besides,photothermal local surface plasmon resonance was introduced to accelerate the kinetics of photoelectrochemical reactions at the interface when the special Ag nanoparticles were loaded to extend the absorbance to near infrared light.Consequently,a recordable photocurrent density of 12.73 mA cm^(-2) has been achieved at 1.23 V versus RHE,approaching a theoretical limit of the tantalum nitride photoanode with full-spectrum solar utilization.Meanwhile,compared to the applied bias photon-to-current efficiency of 1.36%without photothermal factor,a high applied bias photonto-current efficiency of 2.27%could be raised by applying local surface plasmon resonance to photoelectrochemical oxygen evolution reaction.The efficient design could maximize the use of solar light via the classification of spectrum and,therefore,may spark more innovative ideas for the future design and development of the next-generation photoelectrode.展开更多
Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylat...Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylation-hydrogenation processes.This study systematically evaluates the catalytic performance of various zeolites(Hβ,HZSM-5,MCM-41 and HUSY)in the alkylation reaction of phenol with cyclohexanol.Characterization results demonstrate that HUSY zeolite showed superior catalytic activity compared to other zeolites,attributable to its favorable pore architecture and well-balanced acid site distribution that synergistically facilitate molecular diffusion and catalytic transformations.To further enhance the catalytic properties,HUSY zeolite was modified with citric acid at various concentrations and compared with those treated with NaOH and oxalic acid.The results revealed that citric acid treatment preserved the crystallinity of the zeolite while modulating its acid distribution and pore structure.All modified zeolites enhanced phenol alkylation activity.Notably,the HUSY-0.5M catalyst,which exhibited the highest medium-strong acid to total acid ratio,achieved superior catalytic performance,80.4%conversion of phenol and 99.6%selectivity for alkylation products.The catalyst also exhibited high activity in the alkylation of various lignin-derived compounds,demonstrating its broad applicability.This work provides a new strategy for the valorization of lignin-derived phenols into high-value fuel precursors through alkylation.展开更多
Carbon dioxide(CO_(2))is the primary greenhouse gas contributing to anthropogenic climate change which is associated with human activities.The majority of CO_(2) emissions are results of the burning of fossil fuels fo...Carbon dioxide(CO_(2))is the primary greenhouse gas contributing to anthropogenic climate change which is associated with human activities.The majority of CO_(2) emissions are results of the burning of fossil fuels for energy,as well as industrial processes such as steel and cement production.Carbon capture,utilization,and storage(CCUS)is a sustainable technology promising in terms of reducing CO_(2) emissions that would otherwise contribute to climate change.From this perspective,the discussion on carbon capture focuses on chemical absorption technology,primarily due to its commercialization potential.The CO_(2) absorptive capacity and absorption rate of various chemical solvents have been summarized.The carbon utilization focuses on electrochemical conversion routes converting CO_(2) into potentially valuable chemicals which have received particular attention in recent years.The Faradaic conversion efficiencies for various CO_(2) reduction products are used to describe efficiency improvements.For carbon storage,successful deployment relies on a better understanding of fluid mechanics,geomechanics,and reactive transport,which are discussed in details.展开更多
A 100 Nm3 /hr capacity pilot scale dual bag filter （DBF） system was tested on the flue gas from an actual hazardous waste incinerator （HWI）, the removal efficiency of polychlorinated dibenzo-p-dioxins and polychlo...A 100 Nm3 /hr capacity pilot scale dual bag filter （DBF） system was tested on the flue gas from an actual hazardous waste incinerator （HWI）, the removal efficiency of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans （PCDD/Fs） and polychlorinated biphenyls （PCBs） was also studied. The first filter collected most of the fly ash and associated chlorinated organic; then activated carbon （AC） was injected and used to collect phase chlorinated organic from the gas. Concentrations of PCDD/Fs and PCBs after the DBF system were 0.07 and 0.01 ng TEQ/Nm3 , respectively, which were both far below the national emission standard. Comparing with the original single bag filter system, the PCDD/Fs concentration dropped a lot from 0.36 to 0.07 ng TEQ/Nm3 . Increasing AC feeding rate enhanced their collection efficiency, yet reduced the AC utilization efficiency, and it still needs further study to select an appropriate feeding rate in the system. These results will be useful for industrial application and assist in controlling emissions of PCDD/Fs and other persistent organic pollutions from stationary sources in China.展开更多
A kinetic model is proposed for simulating the trajectory of a single milling ball in a planetary ball mill, and a model is also proposed for simulating the local energy transfer during the ball milling process under ...A kinetic model is proposed for simulating the trajectory of a single milling ball in a planetary ball mill, and a model is also proposed for simulating the local energy transfer during the ball milling process under no-slip conditions. Based on the kinematics of ball motion, the collision fi＇equency and power are described, and the normal impact forces and effective power are derived from analyses of collision geometry. The Hertzian impact theory is applied to formulate these models after having established some relationships among the geometric, dynamic, and thermophysical parameters. Simulation is carried out based on two models, and the effects of the rotation velocity of the planetary disk Ω and the vial-to-disk speed ratio ω/Ω on other kinetic parameters is investigated. As a result, the optimal ratio ω/Ω to obtain high impact energy in the standard operating condition at Ω = 800 rpm is estimated, and is equal to 1.15.展开更多
The experimental test of co-incinerating Chinese raw municipal solid waste （MSW） and coal in a laboratory-scale tubular reactor was first reported in present study, and the emission of normal gas components and the ...The experimental test of co-incinerating Chinese raw municipal solid waste （MSW） and coal in a laboratory-scale tubular reactor was first reported in present study, and the emission of normal gas components and the effects of the S/Cl molar ratio or coal mixing percentages on polychlorinated dibenzo-p-dioxins and dibenzofurans （PCDDs/Fs） emission were investigated and discussed. The results indicated that OCDD was the only PCDD homologues since others like TCDD-HpCDD was hardly detected, while as the categories of PCDF homologues were comparatively much more general. The amount of PCDD was much larger than that of PCDF in all operating conditions. Since ZPCDF/∑PCDD〈〈1, the dominant role of the precursor formation was proven in our experimental conductions. With increasing the coal addition to MSW （from 0 to 16%）, PCDD and PCDF were reduced considerably. Coal and MSW may suppress the PCDD/F emissions efficiently （over 95%） during the MSW incineration process. The PCDD/F suppression results of the present study could be helpful guidance to the industrial application of Chinese MSW and auxiliary coal co-incineration processes. The PCDD/F stack emission data of two industrial incinerators using co-incineration technology in China seem to have a great positive reduction of PCDDs/Fs.展开更多
Gassolid hydrodynamic steadystate operation is the operating basis in a chemical looping dualreactor system.This study reported the experimental results on the steadystate operation characteristics of gassolid flow in...Gassolid hydrodynamic steadystate operation is the operating basis in a chemical looping dualreactor system.This study reported the experimental results on the steadystate operation characteristics of gassolid flow in a 15.5 m high dual circulating fluidized bed(CFB)cold test system.The effects of superficial gas velocity,static bed material height and solid returning modes on the steadystate operation characteristics between the two CFBs were investigated.Results suggest that the solid distributions in the dual CFB test system was mainly determined by the superficial gas velocity and larger solid inventory may help to improve the solid distributions.Besides,crossreturning mode coupled with selfreturning is good for steadystate running in the dualreactor test system.展开更多
An analysis approach considering gas-solids hydrodynamics,reaction kinetics and reacting species nonuniformity together in a dual-reactor system is presented for better understanding its mass and energy balance.It was...An analysis approach considering gas-solids hydrodynamics,reaction kinetics and reacting species nonuniformity together in a dual-reactor system is presented for better understanding its mass and energy balance.It was achieved by a 3-dimensional comprehensive hydrodynamics and reaction model for the dual-reactor system,which was developed from the successfully verified 3-dimensional comprehensive combustion model for one circulating fluidized bed(CFB)system(Xu and Cheng,2019).The developed model and analysis approach was successfully used on a 1 MW circulating fluidized bed–bubbling fluidized bed(CFB-BFB)dual-reactor system.Results showed the sensible and chemical energy between two reactors as well as the energy distributions in each reactor were balanced and they agreed well with the experimental measurements.The analysis approach indicated energy balance had a close relationship with the mass transfer in the CFB-BFB dual-reactor system.It may be applied in a design and operation optimization for a dual-reactor system.展开更多
The numerical model was presented for the coal combustion in the packed bed. The bifurcation characteristic of the ignition-extinction of solid-phase smoldering and tran- sition to flaming was studied for the packed b...The numerical model was presented for the coal combustion in the packed bed. The bifurcation characteristic of the ignition-extinction of solid-phase smoldering and tran- sition to flaming was studied for the packed bed of coal.One of the Frank-Kamenetskii parameter β_1 was selected as the control parameter.The computed results show that the bifurcation curve is obviously divided into two zones of solid-phase reaction and gas- phase reaction,and the total process of ignition-extinction presents twice bifurcation cha- racteristic.Moreover,the vanishing of critical state of ignition-extinction is studied.One of the transition points,ε_2=0.05,is numerically solved for the vanishing of critical state.The larger the value of ε_2 is,the easier the gas-phase can react.However,the combustion temperature will decrease with increasing ε_2.The other transition point α_2=0.53 is also ob- tained.With increasing the value of α_2,the combustion temperature of gas-phase reaction is close to the smoldering temperature of coal.When α_2 is infinite,the only reaction occur- ring is the smoldering combustion of solid-phase,and the gas-phase cannot react.展开更多
Converting CO_(2)with green hydrogen to methanol as a carbon-neutral liquid fuel is a promising route for the long-term storage and distribution of intermittent renewable energy.Nevertheless,attaining highly efficient...Converting CO_(2)with green hydrogen to methanol as a carbon-neutral liquid fuel is a promising route for the long-term storage and distribution of intermittent renewable energy.Nevertheless,attaining highly efficient methanol synthesis catalysts from the vast composition space remains a significant challenge.Here we present a machine learning framework for accelerating the development of high space-time yield(STY)methanol synthesis catalysts.A database of methanol synthesis catalysts has been compiled,consisting of catalyst composition,preparation parameters,structural characteristics,reaction conditions and their corresponding catalytic performance.A methodology for constructing catalyst features based on the intrinsic physicochemical properties of the catalyst components has been developed,which significantly reduced the data dimensionality and enhanced the efficiency of machine learning operations.Two high-precision machine learning prediction models for the activities and product selectivity of catalysts were trained and obtained.Using this machine learning framework,an efficient search was achieved within the catalyst composition space,leading to the successful identification of high STY multielement oxide methanol synthesis catalysts.Notably,the CuZnAlTi catalyst achieved high STYs of 0.49 and 0.65 g_(MeOH)/(g_(catalyst)h)for CO_(2)and CO hydrogenation to methanol at 250℃,respectively,and the STY was further increased to 2.63 g_(Me OH)/(g_(catalyst)h)in CO and CO_(2)co-hydrogenation.展开更多
The role of catalysts in enhancing the hydrogen storage kinetics of the Mg/MgH_(2)system is pivotal.However,the exploration of efficient catalysts and the underlying principles of their design remain both a prominent ...The role of catalysts in enhancing the hydrogen storage kinetics of the Mg/MgH_(2)system is pivotal.However,the exploration of efficient catalysts and the underlying principles of their design remain both a prominent focus and a significant challenge in current research.In this study,we present a bimetallic oxide of Bi_(2)Ti_(2)O_(7)hollow sphere as a highly effective catalyst for MgH_(2).As a result,the Bi_(2)Ti_(2)O_(7)-catalyzed Mg/MgH_(2)system lowers the hydrogen desorption initiation temperature to 194.3℃,reduces the peak desorption temperature to 245.6℃,decreases the dehydrogenation activation energy to 82.14 kJ·mol^(−1),and can absorb 5.4 wt.%of hydrogen within 60 s at 200℃,demonstrating outstanding hydrogen ab/desorption kinetics,compared to pure MgH_(2).Additionally,it can maintain a high hydrogen capacity of 5.2 wt.%,even after 50 dehydrogenation cycles,showing good cycle stability.The characterization results show that the high-valent Bi and Ti in Bi_(2)Ti_(2)O_(7)are reduced to their low-valent or even zero-valent metallic states during the dehydrogenation and hydrogenation process,thus establishing an in-situ multivalent and multi-element catalytic environment.Density functional theory calculations further reveal that the synergistic effects between Bi and Ti in the Bi-Ti mixed oxide facilitate the cleavage of Mg-H bonds and lower the kinetic barrier for the dissociation of hydrogen molecules,thereby substantially enhancing the kinetics of the Mg/MgH_(2)system.This study presents a strategic method for developing efficient catalysts for hydrogen storage materials by harnessing the synergistic effects of metal elements.展开更多
Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising a...Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.展开更多
Biocompatible amphiphilic nanoparticles(NPs)with tunable particle morphology and surface property are important for their applications as functional materials.However,previously developed methods to prepare amphiphili...Biocompatible amphiphilic nanoparticles(NPs)with tunable particle morphology and surface property are important for their applications as functional materials.However,previously developed methods to prepare amphiphilic NPs generally involve several steps,especially an additional step for surface modification,greatly hindering their largescale production and widespread applications.Here,a versatile one-step strategy is developed to prepare biocompatible amphiphilic dimer NPs with tunable particle morphology and surface property.The amphiphilic dimer NPs,which consist of a hydrophobic shellac bulb and a hydrophilic poly(lactic acid)(PLA)bulb with PLA-poly(ethylene glycol)(PEG)on the bulb surface,are prepared in a single step by controlled co-precipitation and self-assembly.Amphiphilic PLA-PEG/shellac dimer NPs demonstrate excellent tunability in particle morphology,thus showing good performances in controlling the interfacial curvature and emulsion type.In addition,temperatureresponsive PLA-poly(N-isopropyl acrylamide)(PNIPAM)/shellac dimer NPs are prepared following the same method and emulsions stabilized by them show temperature-triggered response.The applications of PLA-PEG-folic acid(FA)/shellac dimer NPs for drug delivery have also been demonstrated,which show a very good performance.The strategy of preparing the dimer NPs is green,scalable,facile and versatile,which provides a good platform for the design of dimer NPs with tunable particle morphology and surface property for diverse applications.展开更多
Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, th...Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, their application is hindered by poor cycling stability, resulting from severe volume changes during cycling and slow reaction kinetics due to their complex crystal structure. Here, an efficient and straightforward strategy was employed to in-situ encapsulate single-phase porous nanocubic MnS_(0.5)Se_(0.5) into carbon nanofibers using electrospinning and the hard template method, thus forming a necklace-like porous MnS_(0.5)Se_(0.5)-carbon nanofiber composite(MnS_(0.5)Se_(0.5)@N-CNF). The introduction of Se significantly impacts both the composition and microstructure of MnS_(0.5)Se_(0.5), including lattice distortion that generates additional defects, optimization of chemical bonds, and a nano-spatially confined design. In situ/ex-situ characterization and density functional theory calculations verified that this MnS_(0.5)Se_(0.5)@N-CNF allevi- ates the volume expansion and facilitates the transfer of Na+/electron. As expected, MnS_(0.5)Se_(0.5)@N-CNF anode demonstrates excellent sodium storage performance, characterized by high initial Coulombic efficiency(90.8%), high-rate capability(370.5 m Ahg^(-1) at 10 Ag^(-1)) and long durability(over 5000 cycles at 5 Ag^(-1)). The MnS_(0.5)Se_(0.5)@N-CNF//NVP@C full cell, assembled with MnS_(0.5)Se_(0.5)@N-CNF as anode and Na_(3)V_(2)(PO_4)_(3)@C as cathode, exhibits a high energy density of 254 Wh kg^(-1) can be provided. This work presents a novel strategy to optimize the design of anode materials through structural engineering and Se substitution, while also elucidating the underlying reaction mechanisms.展开更多
The catalytic steam reforming(SR)of biomass-derived organic compounds could be considered as a promising route to generate H_(2)fuel.This work aimed to achieve efficient H_(2)production by the SR of aqueous products o...The catalytic steam reforming(SR)of biomass-derived organic compounds could be considered as a promising route to generate H_(2)fuel.This work aimed to achieve efficient H_(2)production by the SR of aqueous products obtained from the hydrothermal conversion process of lignocellulosic biomass.The catalytic SR was studied over 15Ni/NiAl_(2)O_(4)for model compound mixtures composed of furfural,levulinic acid,and formic acid.At a reaction temperature of 800℃,the high H_(2)yield of 93.8%was achieved.Bimetallic Ni-Cu and Ni-Co catalysts supported by NiAl_(2)O_(4)were synthesized to optimize the SR performance in the presence of H_(2)SO_(4)as impurity.The Ni-Co and Cu-Ni alloys formed on the bimetallic catalysts during calcination and reduction were verified.The results revealed that the alloys formation improved the resistance of catalysts to oxidation and H_(2)SO_(4),thus weakening the catalyst deactivation during the SR process.Importantly,the catalytic SR was successfully applied to convert aqueous products from the hydrothermal conversion of pine sawdust.This study provides an encouraging route for upgrading biomass into high-value fuels.展开更多
Carbon dioxide(CO_(2))is the predominant greenhouse gas in the Earth’s atmosphere and plays a crucial role in global warming.Given the inherent limitations of monoethanolamine absorbents in current commercial large-s...Carbon dioxide(CO_(2))is the predominant greenhouse gas in the Earth’s atmosphere and plays a crucial role in global warming.Given the inherent limitations of monoethanolamine absorbents in current commercial large-scale CO_(2)capture applications,amino acid ionic liquids(AAILs)have garnered extensive interest in this field due to their adjustable structure,low volatility,high thermal stability,and significant absorption capacity.However,the number of comprehensive reviews recently published on the CO_(2)absorption by AAILs remains limited.In addition,researchers have differing opinions on the AAILs/CO_(2)reaction mechanisms.Therefore,this review provides a thorough overview of the reaction mechanisms and structure-activity relationships associated with AAILs for CO_(2)capture.Moreover,it outlines the research advancements in pure AAILs and their mixtures,including aqueous AAILs and AAIL-organic solvent mixtures.The effects of varying ionic structures and additives on the absorption properties of AAILs are examined in detail.In conclusion,although AAILs exhibit high CO_(2)absorption loading and possess numerous appealing characteristics,further research is essential to comprehensively evaluate their viability for large-scale CO_(2)capture from flue gas.展开更多
In this study,the modified split Hopkinson pressure bar(SHPB)system,complemented by synchronized high-speed holography and direct shooting imaging techniques,was employed to investigate the impact-induced mechanical,i...In this study,the modified split Hopkinson pressure bar(SHPB)system,complemented by synchronized high-speed holography and direct shooting imaging techniques,was employed to investigate the impact-induced mechanical,ignition and reaction growth behavior of high-ductility composite energetic materials(CEMs).The experiments were performed over a large range of strain rate conditions of 3,000–6,000 s^(-1)for samples containing different components of solid explosive granules.The strainstress relationships,onset of ignition and reaction growth in impact-induced debris clouds were quantitatively studied.The results show that ignition was a result of compression and deformation,triggered significantly by the effects of shear extrusion friction.The critical strain rate of ignition was approximately 4,000–5,000 s^(-1).The average particle size inside the debris before and after ignition ranges from 41.3 to 49.5μm.The particle quantity and size produced by the impact of the CEM increase as the strain rate increases.The sustainability of the ignition,or its rapid quenching,was tightly correlated with the size and density of the impact-induced debris cloud.For high-strain rate impacts,denser debris clouds were produced,which effectively favors the sustaining and propagation of the initial ignition core.The results provide valuable insights for establishing the criteria of the impact induced reaction growth and enhancing the safety and reliability of high-ductility energetic materials used in aerospace and national defense applications.展开更多
Chemical hydrogen storage technology is crucial for the widespread use of hydrogen,with significant research progress being made in hydrazine hydrate(N_(2)H_(4)·H_(2)O).However,the efficient decomposition of N_(2...Chemical hydrogen storage technology is crucial for the widespread use of hydrogen,with significant research progress being made in hydrazine hydrate(N_(2)H_(4)·H_(2)O).However,the efficient decomposition of N_(2)H_(4)·H_(2)O remains a major challenge,hindered by dynamic constraints.To address this,we prepared NiPt nanoparticles deposited onto urchin-like TiO_(2)(u-TiO_(2))using the impregnation-reduction method,resulting in the NiPt/u-TiO_(2)catalyst.Remarkably,the Ni0.5Pt0.5/u-TiO_(2)catalyst demonstrated 100%H_(2)selectivity,ultrahigh catalytic activity and remarkable durability for N_(2)H_(4)·H_(2)O dehydrogenation,with a turnover frequency(TOF)of115.8 min^(-1),surpassing that of the corresponding NiPt/commercial TiO_(2)(c-TiO_(2)).Characterization and experimental findings suggest that the remarkable activity may originate from the unique urchin-like structure of the catalyst,along with the synergistic interaction between NiPt metals and the support.This research opens new avenues for designing nanomaterials with morphology advantages for hydrogen evolution reaction.展开更多
The latent heat thermal energy storage system with solid-liquid phase-change material(SLPCM-LHTES)as energy storage medium provides outstanding advantages such as system simplicity,stable temperature control,and high ...The latent heat thermal energy storage system with solid-liquid phase-change material(SLPCM-LHTES)as energy storage medium provides outstanding advantages such as system simplicity,stable temperature control,and high energy storage density,showing great potential toward addressing the energy storage problems associated with decentralized,intermittent,and unstable renewable energy sources.Notably,effective heat transfer within the SLPCM-LHTES is crucial for extending its application potential.Therefore,a comprehensive understanding of the heat transfer processes in SLPCM-LHTES from a theoretical perspective is necessary.In this review,we propose a three-stage heat transfer pathway in SLPCM-LHTES,including external heating,interfacial heat transfer,and intrinsic phase transition processes.From the perspective of this three-stage pathway,the theoretical basis of heat transfer processes and typical efficiency enhancement strategies in SLPCM-LHTES are summarized.Moreover,an overview of the typical applications of SLPCM-LHTES in various fields,such as building energy efficiency,textiles and garments,and battery thermal management,is presented.Finally,the remaining challenges and possible avenues of research in this burgeoning field will also be discussed.展开更多
A process capable of simultaneously oxidizing NO,SO2,and Hg^0 was proposed,using a nigh-voltage and short-duration positive pulsed corona discharge.By focusing on NO,SO2,and Hg^0 oxidation efficiencies,the influences ...A process capable of simultaneously oxidizing NO,SO2,and Hg^0 was proposed,using a nigh-voltage and short-duration positive pulsed corona discharge.By focusing on NO,SO2,and Hg^0 oxidation efficiencies,the influences of pulse peak voltage,pulse frequency,initial concentration,electrode number,residence time and water vapor addition were investigated.The results indicate that NO,SO2 and Hg^0 oxidation efficiencies depend primarily on the radicals(OH,HO_(2),O)and the active species(O3,H2O2,etc.)produced by the pulsed corona discharge.The NO,SO2 and Hg^0 oxidation efficiencies could be improved as pulse peak voltage,pulse frequency,electrode number and residence time increased,but they were reduced with increasing initial concentrations.By adding water vapor,the SO2 oxidation efficiency was improved remarkably,while the NO oxidation efficiency decreased slightly.In our experiments,the simultaneous NO,SO2,and Hg^0 oxidation efficiencies reached to 40%,98%,and 55%with the initial concentrations 479 mg/m^3,1040 mg/m^3,and 15.0μg/m^3,respectively.展开更多
基金financially supported by the Zhejiang Provincial Natural Science Foundation of China under Grant No.LQ24E060001the National Key Research and Development Project(2023YFC3710800)+2 种基金the National Natural Science Foundation of China under Grant No.52341602supported by funding from the Canada First Research Excellence Fund(CFRER-2015-00001)the University of Alberta’s Future Energy Systems research initiative(FES-T02-P03)。
文摘Tantalum nitride is widely considered as a promising photoanode material for its suitable band structure as well as the high theoretical conversion efficiency in solar water splitting.However,it is limited to inefficient photoinduced electron–hole pair separation and interfacial dynamics in the photoelectrochemical oxygen evolution reaction.Herein,multiple layers including Ti_(x)Si_(y) and NiFeCoO_(x) were fabricated based on band engineering to regulate tandem electric states for efficient transfer of energy carriers.Besides,photothermal local surface plasmon resonance was introduced to accelerate the kinetics of photoelectrochemical reactions at the interface when the special Ag nanoparticles were loaded to extend the absorbance to near infrared light.Consequently,a recordable photocurrent density of 12.73 mA cm^(-2) has been achieved at 1.23 V versus RHE,approaching a theoretical limit of the tantalum nitride photoanode with full-spectrum solar utilization.Meanwhile,compared to the applied bias photon-to-current efficiency of 1.36%without photothermal factor,a high applied bias photonto-current efficiency of 2.27%could be raised by applying local surface plasmon resonance to photoelectrochemical oxygen evolution reaction.The efficient design could maximize the use of solar light via the classification of spectrum and,therefore,may spark more innovative ideas for the future design and development of the next-generation photoelectrode.
基金Supported by National Key Research&Development Program of China (2022YFB4201800)Key Program of National Natural Science Foundation of China (52130610)。
文摘Lignin-derived oxygenated aromatics,particularly phenols and aromatic ethers obtained through depolymerization,represent promising feedstocks for synthesizing high-density and high-heat-sink aviation fuels via alkylation-hydrogenation processes.This study systematically evaluates the catalytic performance of various zeolites(Hβ,HZSM-5,MCM-41 and HUSY)in the alkylation reaction of phenol with cyclohexanol.Characterization results demonstrate that HUSY zeolite showed superior catalytic activity compared to other zeolites,attributable to its favorable pore architecture and well-balanced acid site distribution that synergistically facilitate molecular diffusion and catalytic transformations.To further enhance the catalytic properties,HUSY zeolite was modified with citric acid at various concentrations and compared with those treated with NaOH and oxalic acid.The results revealed that citric acid treatment preserved the crystallinity of the zeolite while modulating its acid distribution and pore structure.All modified zeolites enhanced phenol alkylation activity.Notably,the HUSY-0.5M catalyst,which exhibited the highest medium-strong acid to total acid ratio,achieved superior catalytic performance,80.4%conversion of phenol and 99.6%selectivity for alkylation products.The catalyst also exhibited high activity in the alkylation of various lignin-derived compounds,demonstrating its broad applicability.This work provides a new strategy for the valorization of lignin-derived phenols into high-value fuel precursors through alkylation.
基金the National Natural Science Foun-dation of China(51836006).
文摘Carbon dioxide(CO_(2))is the primary greenhouse gas contributing to anthropogenic climate change which is associated with human activities.The majority of CO_(2) emissions are results of the burning of fossil fuels for energy,as well as industrial processes such as steel and cement production.Carbon capture,utilization,and storage(CCUS)is a sustainable technology promising in terms of reducing CO_(2) emissions that would otherwise contribute to climate change.From this perspective,the discussion on carbon capture focuses on chemical absorption technology,primarily due to its commercialization potential.The CO_(2) absorptive capacity and absorption rate of various chemical solvents have been summarized.The carbon utilization focuses on electrochemical conversion routes converting CO_(2) into potentially valuable chemicals which have received particular attention in recent years.The Faradaic conversion efficiencies for various CO_(2) reduction products are used to describe efficiency improvements.For carbon storage,successful deployment relies on a better understanding of fluid mechanics,geomechanics,and reactive transport,which are discussed in details.
基金supported by the Basic Research Development Program (973) of China (No. 2011CB201500)the National High Technology Research and Development Key Program of China (No. 2012AA062803)+1 种基金the Public Welfare Projects for Environmental Protection (No. 201209022)the Fundamental Research Funds for the Central Universities (No. 2012QNA4009)
文摘A 100 Nm3 /hr capacity pilot scale dual bag filter （DBF） system was tested on the flue gas from an actual hazardous waste incinerator （HWI）, the removal efficiency of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans （PCDD/Fs） and polychlorinated biphenyls （PCBs） was also studied. The first filter collected most of the fly ash and associated chlorinated organic; then activated carbon （AC） was injected and used to collect phase chlorinated organic from the gas. Concentrations of PCDD/Fs and PCBs after the DBF system were 0.07 and 0.01 ng TEQ/Nm3 , respectively, which were both far below the national emission standard. Comparing with the original single bag filter system, the PCDD/Fs concentration dropped a lot from 0.36 to 0.07 ng TEQ/Nm3 . Increasing AC feeding rate enhanced their collection efficiency, yet reduced the AC utilization efficiency, and it still needs further study to select an appropriate feeding rate in the system. These results will be useful for industrial application and assist in controlling emissions of PCDD/Fs and other persistent organic pollutions from stationary sources in China.
基金Project supported by the Major State Basic Research Development Program of China (Grant No. 2011CB201500)the Science and Technology Project of Zhejiang Province, China (Grant No. 2009C13004)+2 种基金the National Key Technology R&D Program of China(Grant No. 2007BAC27B04-4)the Program of Introducing Talents of Disciplinary to University, China (Grant No. B08026)Y. C. Tang Disciplinary Development Fund of Zhejiang University, China
文摘A kinetic model is proposed for simulating the trajectory of a single milling ball in a planetary ball mill, and a model is also proposed for simulating the local energy transfer during the ball milling process under no-slip conditions. Based on the kinematics of ball motion, the collision fi＇equency and power are described, and the normal impact forces and effective power are derived from analyses of collision geometry. The Hertzian impact theory is applied to formulate these models after having established some relationships among the geometric, dynamic, and thermophysical parameters. Simulation is carried out based on two models, and the effects of the rotation velocity of the planetary disk Ω and the vial-to-disk speed ratio ω/Ω on other kinetic parameters is investigated. As a result, the optimal ratio ω/Ω to obtain high impact energy in the standard operating condition at Ω = 800 rpm is estimated, and is equal to 1.15.
基金Project supported by the National Basic Research Program (973) of China(No.G1999022211)the National Natural Science Foun-dation of China(No.59836210).
文摘The experimental test of co-incinerating Chinese raw municipal solid waste （MSW） and coal in a laboratory-scale tubular reactor was first reported in present study, and the emission of normal gas components and the effects of the S/Cl molar ratio or coal mixing percentages on polychlorinated dibenzo-p-dioxins and dibenzofurans （PCDDs/Fs） emission were investigated and discussed. The results indicated that OCDD was the only PCDD homologues since others like TCDD-HpCDD was hardly detected, while as the categories of PCDF homologues were comparatively much more general. The amount of PCDD was much larger than that of PCDF in all operating conditions. Since ZPCDF/∑PCDD〈〈1, the dominant role of the precursor formation was proven in our experimental conductions. With increasing the coal addition to MSW （from 0 to 16%）, PCDD and PCDF were reduced considerably. Coal and MSW may suppress the PCDD/F emissions efficiently （over 95%） during the MSW incineration process. The PCDD/F suppression results of the present study could be helpful guidance to the industrial application of Chinese MSW and auxiliary coal co-incineration processes. The PCDD/F stack emission data of two industrial incinerators using co-incineration technology in China seem to have a great positive reduction of PCDDs/Fs.
文摘Gassolid hydrodynamic steadystate operation is the operating basis in a chemical looping dualreactor system.This study reported the experimental results on the steadystate operation characteristics of gassolid flow in a 15.5 m high dual circulating fluidized bed(CFB)cold test system.The effects of superficial gas velocity,static bed material height and solid returning modes on the steadystate operation characteristics between the two CFBs were investigated.Results suggest that the solid distributions in the dual CFB test system was mainly determined by the superficial gas velocity and larger solid inventory may help to improve the solid distributions.Besides,crossreturning mode coupled with selfreturning is good for steadystate running in the dualreactor test system.
基金The authors are grateful for the financial support of the National Key Research and Development Program of China(2018YFB0605403).
文摘An analysis approach considering gas-solids hydrodynamics,reaction kinetics and reacting species nonuniformity together in a dual-reactor system is presented for better understanding its mass and energy balance.It was achieved by a 3-dimensional comprehensive hydrodynamics and reaction model for the dual-reactor system,which was developed from the successfully verified 3-dimensional comprehensive combustion model for one circulating fluidized bed(CFB)system(Xu and Cheng,2019).The developed model and analysis approach was successfully used on a 1 MW circulating fluidized bed–bubbling fluidized bed(CFB-BFB)dual-reactor system.Results showed the sensible and chemical energy between two reactors as well as the energy distributions in each reactor were balanced and they agreed well with the experimental measurements.The analysis approach indicated energy balance had a close relationship with the mass transfer in the CFB-BFB dual-reactor system.It may be applied in a design and operation optimization for a dual-reactor system.
基金the National Natural Science Foundation(50574049)National Key Technology R&D Pogram of China(2006BAK03B05)
文摘The numerical model was presented for the coal combustion in the packed bed. The bifurcation characteristic of the ignition-extinction of solid-phase smoldering and tran- sition to flaming was studied for the packed bed of coal.One of the Frank-Kamenetskii parameter β_1 was selected as the control parameter.The computed results show that the bifurcation curve is obviously divided into two zones of solid-phase reaction and gas- phase reaction,and the total process of ignition-extinction presents twice bifurcation cha- racteristic.Moreover,the vanishing of critical state of ignition-extinction is studied.One of the transition points,ε_2=0.05,is numerically solved for the vanishing of critical state.The larger the value of ε_2 is,the easier the gas-phase can react.However,the combustion temperature will decrease with increasing ε_2.The other transition point α_2=0.53 is also ob- tained.With increasing the value of α_2,the combustion temperature of gas-phase reaction is close to the smoldering temperature of coal.When α_2 is infinite,the only reaction occur- ring is the smoldering combustion of solid-phase,and the gas-phase cannot react.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(LDT23E06012E06)National Key R&D Program of China(2023YFC3710800)+3 种基金the National EnergySaving and Low-Carbon Materials Production and Application Demonstration Platform Program(TC220H06N)Pioneer R&D Program of Zhejiang Province-China(2024SSYS0066,2023C03016)National Natural Science Foundation of China(42341208)Zhejiang Energy Group Research Fund(ZNKJ-2023-100)。
文摘Converting CO_(2)with green hydrogen to methanol as a carbon-neutral liquid fuel is a promising route for the long-term storage and distribution of intermittent renewable energy.Nevertheless,attaining highly efficient methanol synthesis catalysts from the vast composition space remains a significant challenge.Here we present a machine learning framework for accelerating the development of high space-time yield(STY)methanol synthesis catalysts.A database of methanol synthesis catalysts has been compiled,consisting of catalyst composition,preparation parameters,structural characteristics,reaction conditions and their corresponding catalytic performance.A methodology for constructing catalyst features based on the intrinsic physicochemical properties of the catalyst components has been developed,which significantly reduced the data dimensionality and enhanced the efficiency of machine learning operations.Two high-precision machine learning prediction models for the activities and product selectivity of catalysts were trained and obtained.Using this machine learning framework,an efficient search was achieved within the catalyst composition space,leading to the successful identification of high STY multielement oxide methanol synthesis catalysts.Notably,the CuZnAlTi catalyst achieved high STYs of 0.49 and 0.65 g_(MeOH)/(g_(catalyst)h)for CO_(2)and CO hydrogenation to methanol at 250℃,respectively,and the STY was further increased to 2.63 g_(Me OH)/(g_(catalyst)h)in CO and CO_(2)co-hydrogenation.
基金supported by the National Key Research and Development Program of China(No.2024YFB4007204,2022YFB4004301)the National Natural Science Founda-tion of China(Grant Nos.52477220,52301287,22005353)+2 种基金the Two-chain Integration Key Project of Shaanxi Province(2021LLRH-09)the Key Research and Development Program of Shaanxi Province(No.2024CY2-GJHX-44,2024CY2-GJHX-53,2024GX-ZDCYL-04-06)the Key Industrial Chain Technology Research Program of Xi’an city(23LL-RHZDZX0017).
文摘The role of catalysts in enhancing the hydrogen storage kinetics of the Mg/MgH_(2)system is pivotal.However,the exploration of efficient catalysts and the underlying principles of their design remain both a prominent focus and a significant challenge in current research.In this study,we present a bimetallic oxide of Bi_(2)Ti_(2)O_(7)hollow sphere as a highly effective catalyst for MgH_(2).As a result,the Bi_(2)Ti_(2)O_(7)-catalyzed Mg/MgH_(2)system lowers the hydrogen desorption initiation temperature to 194.3℃,reduces the peak desorption temperature to 245.6℃,decreases the dehydrogenation activation energy to 82.14 kJ·mol^(−1),and can absorb 5.4 wt.%of hydrogen within 60 s at 200℃,demonstrating outstanding hydrogen ab/desorption kinetics,compared to pure MgH_(2).Additionally,it can maintain a high hydrogen capacity of 5.2 wt.%,even after 50 dehydrogenation cycles,showing good cycle stability.The characterization results show that the high-valent Bi and Ti in Bi_(2)Ti_(2)O_(7)are reduced to their low-valent or even zero-valent metallic states during the dehydrogenation and hydrogenation process,thus establishing an in-situ multivalent and multi-element catalytic environment.Density functional theory calculations further reveal that the synergistic effects between Bi and Ti in the Bi-Ti mixed oxide facilitate the cleavage of Mg-H bonds and lower the kinetic barrier for the dissociation of hydrogen molecules,thereby substantially enhancing the kinetics of the Mg/MgH_(2)system.This study presents a strategic method for developing efficient catalysts for hydrogen storage materials by harnessing the synergistic effects of metal elements.
基金supported by the National Natural Science Foundation of China(Grant No.W2412060,22325902 and 52171215)the State Key Laboratory of Clean Energy Utilization(Open Fund Project No.ZJUCEU2023002)。
文摘Sodium-ion batteries(SIBs)have attracted significant attention in large-scale energy storage system because of their abundant sodium resource and cost-effectiveness.Layered oxide materials are particularly promising as SIBs cathodes due to their high theoretical capacities and facile synthesis.However,their practical applications are hindered by the limitations in energy density and cycling stability.The comprehensive understanding of failure mechanisms within bulk structure and at the cathode/electrolyte interface of cathodes is still lacking.In this review,the issues related to bulk phase degradation and surface degradation,such as irreversible phase transitions,cation migration,transition metal dissolution,air/moisture instability,intergranular cracking,interfacial reactions,and reactive oxygen loss,are discussed.The latest advances and strategies to improve the stability of layered oxide cathodes and full cells are provided,as well as our perspectives on the future development of SIBs.
基金supported by National Natural Science Foundation of China(No.22278352)National Key Research and Development Program of China(No.2021YFC3001100)+3 种基金Longyan City Science and Technology Plan Project(No.2020LYF17043)Longyan City Science and Technology Plan Project(No.2020LYF17042)ARC Discovery Project(No.DP200101238)and NHMRC Investigator Grant(No.APP2008698)supported by the Harvard Materials Research Science and Engineering Center(No.DMR2011754)。
文摘Biocompatible amphiphilic nanoparticles(NPs)with tunable particle morphology and surface property are important for their applications as functional materials.However,previously developed methods to prepare amphiphilic NPs generally involve several steps,especially an additional step for surface modification,greatly hindering their largescale production and widespread applications.Here,a versatile one-step strategy is developed to prepare biocompatible amphiphilic dimer NPs with tunable particle morphology and surface property.The amphiphilic dimer NPs,which consist of a hydrophobic shellac bulb and a hydrophilic poly(lactic acid)(PLA)bulb with PLA-poly(ethylene glycol)(PEG)on the bulb surface,are prepared in a single step by controlled co-precipitation and self-assembly.Amphiphilic PLA-PEG/shellac dimer NPs demonstrate excellent tunability in particle morphology,thus showing good performances in controlling the interfacial curvature and emulsion type.In addition,temperatureresponsive PLA-poly(N-isopropyl acrylamide)(PNIPAM)/shellac dimer NPs are prepared following the same method and emulsions stabilized by them show temperature-triggered response.The applications of PLA-PEG-folic acid(FA)/shellac dimer NPs for drug delivery have also been demonstrated,which show a very good performance.The strategy of preparing the dimer NPs is green,scalable,facile and versatile,which provides a good platform for the design of dimer NPs with tunable particle morphology and surface property for diverse applications.
基金financially supported by the National Natural Science Foundation of China (No. 22225902, U22A20436, 22209185)National Key Research&Development Program of China (2022YFE0115900, 2023YFA1507101, 2021YFA1501500)+1 种基金the Self-deployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences (No. CXZX-2022-GH04, CXZX-2023-JQ08)Science and Technology Program of Fuzhou (2023-P-009)。
文摘Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, their application is hindered by poor cycling stability, resulting from severe volume changes during cycling and slow reaction kinetics due to their complex crystal structure. Here, an efficient and straightforward strategy was employed to in-situ encapsulate single-phase porous nanocubic MnS_(0.5)Se_(0.5) into carbon nanofibers using electrospinning and the hard template method, thus forming a necklace-like porous MnS_(0.5)Se_(0.5)-carbon nanofiber composite(MnS_(0.5)Se_(0.5)@N-CNF). The introduction of Se significantly impacts both the composition and microstructure of MnS_(0.5)Se_(0.5), including lattice distortion that generates additional defects, optimization of chemical bonds, and a nano-spatially confined design. In situ/ex-situ characterization and density functional theory calculations verified that this MnS_(0.5)Se_(0.5)@N-CNF allevi- ates the volume expansion and facilitates the transfer of Na+/electron. As expected, MnS_(0.5)Se_(0.5)@N-CNF anode demonstrates excellent sodium storage performance, characterized by high initial Coulombic efficiency(90.8%), high-rate capability(370.5 m Ahg^(-1) at 10 Ag^(-1)) and long durability(over 5000 cycles at 5 Ag^(-1)). The MnS_(0.5)Se_(0.5)@N-CNF//NVP@C full cell, assembled with MnS_(0.5)Se_(0.5)@N-CNF as anode and Na_(3)V_(2)(PO_4)_(3)@C as cathode, exhibits a high energy density of 254 Wh kg^(-1) can be provided. This work presents a novel strategy to optimize the design of anode materials through structural engineering and Se substitution, while also elucidating the underlying reaction mechanisms.
基金supported by the National Natural Science Foundation of China(52261135626).
文摘The catalytic steam reforming(SR)of biomass-derived organic compounds could be considered as a promising route to generate H_(2)fuel.This work aimed to achieve efficient H_(2)production by the SR of aqueous products obtained from the hydrothermal conversion process of lignocellulosic biomass.The catalytic SR was studied over 15Ni/NiAl_(2)O_(4)for model compound mixtures composed of furfural,levulinic acid,and formic acid.At a reaction temperature of 800℃,the high H_(2)yield of 93.8%was achieved.Bimetallic Ni-Cu and Ni-Co catalysts supported by NiAl_(2)O_(4)were synthesized to optimize the SR performance in the presence of H_(2)SO_(4)as impurity.The Ni-Co and Cu-Ni alloys formed on the bimetallic catalysts during calcination and reduction were verified.The results revealed that the alloys formation improved the resistance of catalysts to oxidation and H_(2)SO_(4),thus weakening the catalyst deactivation during the SR process.Importantly,the catalytic SR was successfully applied to convert aqueous products from the hydrothermal conversion of pine sawdust.This study provides an encouraging route for upgrading biomass into high-value fuels.
基金supported by the Natural Science Foundation of Shanghai(Grant No.24ZR1426200)the support from the Key Program of the National Natural Science Foundation of China(Grant No.52236004)。
文摘Carbon dioxide(CO_(2))is the predominant greenhouse gas in the Earth’s atmosphere and plays a crucial role in global warming.Given the inherent limitations of monoethanolamine absorbents in current commercial large-scale CO_(2)capture applications,amino acid ionic liquids(AAILs)have garnered extensive interest in this field due to their adjustable structure,low volatility,high thermal stability,and significant absorption capacity.However,the number of comprehensive reviews recently published on the CO_(2)absorption by AAILs remains limited.In addition,researchers have differing opinions on the AAILs/CO_(2)reaction mechanisms.Therefore,this review provides a thorough overview of the reaction mechanisms and structure-activity relationships associated with AAILs for CO_(2)capture.Moreover,it outlines the research advancements in pure AAILs and their mixtures,including aqueous AAILs and AAIL-organic solvent mixtures.The effects of varying ionic structures and additives on the absorption properties of AAILs are examined in detail.In conclusion,although AAILs exhibit high CO_(2)absorption loading and possess numerous appealing characteristics,further research is essential to comprehensively evaluate their viability for large-scale CO_(2)capture from flue gas.
基金supported by the National Natural Science Foundation of China No.U2341288。
文摘In this study,the modified split Hopkinson pressure bar(SHPB)system,complemented by synchronized high-speed holography and direct shooting imaging techniques,was employed to investigate the impact-induced mechanical,ignition and reaction growth behavior of high-ductility composite energetic materials(CEMs).The experiments were performed over a large range of strain rate conditions of 3,000–6,000 s^(-1)for samples containing different components of solid explosive granules.The strainstress relationships,onset of ignition and reaction growth in impact-induced debris clouds were quantitatively studied.The results show that ignition was a result of compression and deformation,triggered significantly by the effects of shear extrusion friction.The critical strain rate of ignition was approximately 4,000–5,000 s^(-1).The average particle size inside the debris before and after ignition ranges from 41.3 to 49.5μm.The particle quantity and size produced by the impact of the CEM increase as the strain rate increases.The sustainability of the ignition,or its rapid quenching,was tightly correlated with the size and density of the impact-induced debris cloud.For high-strain rate impacts,denser debris clouds were produced,which effectively favors the sustaining and propagation of the initial ignition core.The results provide valuable insights for establishing the criteria of the impact induced reaction growth and enhancing the safety and reliability of high-ductility energetic materials used in aerospace and national defense applications.
基金financially supported by the National Natural Science Foundation of China(Nos.22478001,U22A20408 and 22108238)the Excellent Young Scholars Program of Natural Science Foundation Anhui Province(No.2408085Y005)+3 种基金the Excellent Youth Scholars Program of Higher Education Institutions of Anhui Province(No.2024AH030008)the Open Fund of Shanghai Jiao Tong University Shaoxing Research Institute(No.JDSX2023014)the State Key Laboratory of Clean Energy Utilization(No.ZJUCEU2024017)the Outstanding Scientific Research and Innovation Team Program of Higher Education Institutions of Anhui Province(No.2023AH010015)
文摘Chemical hydrogen storage technology is crucial for the widespread use of hydrogen,with significant research progress being made in hydrazine hydrate(N_(2)H_(4)·H_(2)O).However,the efficient decomposition of N_(2)H_(4)·H_(2)O remains a major challenge,hindered by dynamic constraints.To address this,we prepared NiPt nanoparticles deposited onto urchin-like TiO_(2)(u-TiO_(2))using the impregnation-reduction method,resulting in the NiPt/u-TiO_(2)catalyst.Remarkably,the Ni0.5Pt0.5/u-TiO_(2)catalyst demonstrated 100%H_(2)selectivity,ultrahigh catalytic activity and remarkable durability for N_(2)H_(4)·H_(2)O dehydrogenation,with a turnover frequency(TOF)of115.8 min^(-1),surpassing that of the corresponding NiPt/commercial TiO_(2)(c-TiO_(2)).Characterization and experimental findings suggest that the remarkable activity may originate from the unique urchin-like structure of the catalyst,along with the synergistic interaction between NiPt metals and the support.This research opens new avenues for designing nanomaterials with morphology advantages for hydrogen evolution reaction.
基金financial support was provided by the National Natural Science Foundation of China(Nos.52476146,52006008,and 52471219)the Guangdong Basic and Applied Basic Research Foundation(2023A1515140059 and 2025A1515011255)+2 种基金the Peking University Third Hospital Haidian transformation project(HDCXZHKC2023210)the National Foreign Expert Individual Human Project(Category H,No.H20240116)the State Key Laboratory of New Ceramic Materials Tsinghua University(No.KFZD202402).
文摘The latent heat thermal energy storage system with solid-liquid phase-change material(SLPCM-LHTES)as energy storage medium provides outstanding advantages such as system simplicity,stable temperature control,and high energy storage density,showing great potential toward addressing the energy storage problems associated with decentralized,intermittent,and unstable renewable energy sources.Notably,effective heat transfer within the SLPCM-LHTES is crucial for extending its application potential.Therefore,a comprehensive understanding of the heat transfer processes in SLPCM-LHTES from a theoretical perspective is necessary.In this review,we propose a three-stage heat transfer pathway in SLPCM-LHTES,including external heating,interfacial heat transfer,and intrinsic phase transition processes.From the perspective of this three-stage pathway,the theoretical basis of heat transfer processes and typical efficiency enhancement strategies in SLPCM-LHTES are summarized.Moreover,an overview of the typical applications of SLPCM-LHTES in various fields,such as building energy efficiency,textiles and garments,and battery thermal management,is presented.Finally,the remaining challenges and possible avenues of research in this burgeoning field will also be discussed.
基金supported by the Science and Technology Research of Department of Education of China(No.0305,03087)
文摘A process capable of simultaneously oxidizing NO,SO2,and Hg^0 was proposed,using a nigh-voltage and short-duration positive pulsed corona discharge.By focusing on NO,SO2,and Hg^0 oxidation efficiencies,the influences of pulse peak voltage,pulse frequency,initial concentration,electrode number,residence time and water vapor addition were investigated.The results indicate that NO,SO2 and Hg^0 oxidation efficiencies depend primarily on the radicals(OH,HO_(2),O)and the active species(O3,H2O2,etc.)produced by the pulsed corona discharge.The NO,SO2 and Hg^0 oxidation efficiencies could be improved as pulse peak voltage,pulse frequency,electrode number and residence time increased,but they were reduced with increasing initial concentrations.By adding water vapor,the SO2 oxidation efficiency was improved remarkably,while the NO oxidation efficiency decreased slightly.In our experiments,the simultaneous NO,SO2,and Hg^0 oxidation efficiencies reached to 40%,98%,and 55%with the initial concentrations 479 mg/m^3,1040 mg/m^3,and 15.0μg/m^3,respectively.
