In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220...In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220 kV and a length of 250 km. These overhead power lines (L-213, L-214) connect the 220/110/35 kV “Songino” substation with the “Mandal” substation and form system networks. This paper presents the challenges encountered when implementing single-phase automatic reclosing (SPAR) devices and compares the changes in power system parameters before and after SPAR deployment for a long 220 kV line. Simulations and analyses were carried out using DIgSILENT PowerFactory software, focusing on rotor angle stability, and the overall impact on the power system during short-circuit faults. The evaluation also utilized measurement data from the Wide Area Monitoring System (WAMS) to compare system behavior pre- and post-implementation of SPAR. The findings reveal that SPAR significantly enhances system reliability and stability, effectively mitigating the risk of oscillations and stability loss triggered by short circuits. This improvement contributes to a more resilient power system, reducing the potential for disturbances caused by faults.展开更多
The configuration of a hybrid energy storage system(HESS)plays a pivotal role in mitigating wind power fluctuations and enabling primary frequency regulation,thereby enhancing the active power support capability of wi...The configuration of a hybrid energy storage system(HESS)plays a pivotal role in mitigating wind power fluctuations and enabling primary frequency regulation,thereby enhancing the active power support capability of wind power integration systems.However,most existing studies on HESS capacity configuration overlook the selfrecovery control of the state of charge(SOC),creating challenges in sustaining capacity during long-term operation.This omission can impair frequency regulation performance,increase capacity requirements,and shorten battery lifespan.To address these challenges,this study proposes a bi-level planning–operation capacity configuration model that explicitly incorporates SOC self-recovery control.In the operation layer,a variable-baseline charging/discharging strategy is developed to restore SOC by balancing positive and negative energy over a 24-h period,with the goal of maximizing daily operational benefits.In the planning layer,the annualized net life-cycle cost of the HESS isminimized by configuring storage capacity based on feedback fromthe operation layer.Thetwo layers operate iteratively to achieve coordinated optimization of capacity sizing and control strategy.Case study results demonstrate the effectiveness of the proposed method.Compared with a configuration without considering SOC self-recovery,the proposed approach reduces the 1-min wind power fluctuation rate to 3.53%,lowers the mean squared frequency error to 0.000084,and decreases the annualized net life-cycle cost by 545,000 CNY/MWh.展开更多
As one of the core components of a magnetic refrigerator,magnetic refrigeration materials are expected to have not only a considerable magnetocaloric effect but also excellent thermal conductivity.The poor thermal con...As one of the core components of a magnetic refrigerator,magnetic refrigeration materials are expected to have not only a considerable magnetocaloric effect but also excellent thermal conductivity.The poor thermal conductivity of many competitive oxide-based magnetic refrigerants,exemplified by EuTiO3-based compounds,acts as a major limitation to their practical application.Therefore,improving the thermal conductivity of magnetic refrigeration materials has become a research emphasis of magnetic refrigeration in recent years.In this work,a series of EuTiO_(3)(ETO)/Cu composites with different copper additives was prepared using a solid-phase reaction method by introducing appropriate amounts of copper powder.The influence of the introduction of copper on the phase composition,microstructure,thermal conductivity,and magnetocaloric effect of the composites was systematically investigated.Unexpectedly,the thermal conductivity of the composites is enhanced by up to 260%due to copper addition,accompanied by only a 5%decrease in magnetic entropy change and refrigerating capacity.Copper additive forms localized thermal conductive networks and promotes the densification process,resulting in significantly enhanced thermal conductivity of the composites.This work demonstrates the feasibility of improving the thermal conductivity of oxide-base d magnetic refrigeration materials by introducing highly thermally conductive substances.展开更多
Magnetic refrigeration(MR)technology is regarded as an ideal solution for cryogenic applications,relying on magnetocaloric materials which provide necessary chilling effect.A series of polycrystalline Tm_(1-x)Er_(x)Ni...Magnetic refrigeration(MR)technology is regarded as an ideal solution for cryogenic applications,relying on magnetocaloric materials which provide necessary chilling effect.A series of polycrystalline Tm_(1-x)Er_(x)Ni_(2)Si_(2)(x=0.2,0.4)compounds was synthesized,and their magnetic properties,magnetic phase transition together with magnetocaloric effect(MCE)were studied.The Tm_(1-x)Er_(x)Ni_(2)Si_(2)(x=0.2,0.4)compounds display a field-induced metamagnetic transition from antiferromagnetic(AFM)to ferromagnetism(FM)in excess of 0.2 T,respectively.Meanwhile,the AFM ground state is unstable.Under the field change of 0-2 T,the values of maximal magnetic entropy change(-ΔS_(M)^(max))and refrigerant capacity(RC)for Tm_(0.8)Er_(0.2)Ni_(2)Si_(2)compound are 17.9 J/(kg·K)and 83.5 J/kg,respectively.The large reversible MCE under low magnetic fields(≤2 T)indicates that Tm_(0.8)Er_(0.2)Ni_(2)Si_(2)compound can serve as potential candidate materials for cryogenic magnetic refrigeration.展开更多
Frustrated lanthanide oxides with dense magnetic lattice and suppressed ordering temperature have potential applications in cryogenic magnetic refrigeration.Herein,the crystal structure,magnetic properties,magnetic ph...Frustrated lanthanide oxides with dense magnetic lattice and suppressed ordering temperature have potential applications in cryogenic magnetic refrigeration.Herein,the crystal structure,magnetic properties,magnetic phase transition(MPT)together with magnetocaloric effect(MCE)of LnOF(Ln=Gd,Dy,Ho,and Er)compounds were investigated.Crystallographic study shows that these compounds crystallize in the centrosymmetric space group R3m with an ideal triangular lattice.No long-range magnetic ordering is observed above 2 K for LnOF(Ln=Gd,Ho,and Er).However,DyOF compound undergoes an MPT from paramagnetic(PM)to antiferromagnetic(AFM)at the Neel temperature(TN≈4 K).Considerable reversible MCE is observed in these triangular-lattice compounds.Under the magnetic field change(μ0ΔH)of 0-2 T,the maximum values of magnetic entropy change(-ΔSMmax)of them are 6.1,9.4,12.7,and 14.1 J/(kg·K),respectively.Interestingly,the value of ErOF with Ising-like spin is 2.3 times that of GdOF,which provides an approach for exploring magnetic refrigerants with excellent low-field cryogenic magnetocaloric effect.展开更多
With the intensification of the energy crisis and the worsening greenhouse effect,the development of sustainable integrated energy systems(IES)has become a crucial direction for energy transition.In this context,this ...With the intensification of the energy crisis and the worsening greenhouse effect,the development of sustainable integrated energy systems(IES)has become a crucial direction for energy transition.In this context,this paper proposes a low-carbon economic dispatch strategy under the green hydrogen certificate trading(GHCT)and the ladder-type carbon emission trading(CET)mechanism,enabling the coordinated utilization of green and blue hydrogen.Specifically,a proton exchange membrane electrolyzer(PEME)model that accounts for dynamic efficiency characteristics,and a steam methane reforming(SMR)model incorporating waste heat recovery,are developed.Based on these models,a hydrogen production–storage–utilization framework is established to enable the coordinated deployment of green and blue hydrogen.Furthermore,the gas turbine(GT)unit are retrofitted using oxygenenriched combustion carbon capture(OCC)technology,wherein the oxygen produced by PEME is employed to create an oxygen-enriched combustion environment.This approach reduces energy waste and facilitates low-carbon power generation.In addition,the GHCT mechanism is integrated into the system alongside the ladder-type CET mechanism,and their complementary effects are investigated.A comprehensive optimization model is then formulated to simultaneously achieve carbon reduction and economic efficiency across the system.Case study results show that the proposed strategy reduces wind curtailment by 7.77%,carbon emissions by 65.98%,and total cost by 12.57%.This study offers theoretical reference for the low-carbon,economic,and efficient operation of future energy systems.展开更多
Recent interest in photocatalytic water splitting has intensified the demand in the development of photocatalysts capable of harnessing the full solar-spectrum.This study introduces a novel WO_(x)/ZnIn_(2)S_(4)Zscheme...Recent interest in photocatalytic water splitting has intensified the demand in the development of photocatalysts capable of harnessing the full solar-spectrum.This study introduces a novel WO_(x)/ZnIn_(2)S_(4)Zscheme heterojunction,prepared by depositing ZnIn_(2)S_(4)(ZIS)nanosheets onto WO_(x)nanorods,enabling efficient photothermal-coupled photocatalytic H_(2)evolution.The success relies on the engineered oxygen vacancies within WO_(x)nanorods,which not only confer excellent photothermal properties lowering the reaction barrier but also create defect levels in WO_(x)facilitating Z-scheme electron transfer from these levels to the valence band of ZIS.Consequently,the optimized WO_(x)/ZIS heterojunction exhibits a remarkable H_(2)evolution rate of 33.91 mmol h^(-1)g^(-1)with an apparent quantum efficiency of 23.6%at 400 nm.This study provides a new strategy for developing efficient Z-scheme heterojunctions with broadspectrum solar hydrogen production capabilities.展开更多
Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extrac...Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extracting sustainable and clean energy fromthe salinity gradient energy.However,the scarcity of research investigating the intricate multi-factor coupling effects on the energy conversion performance,especially the trade-offs between ion selectivity and mass transfer in nanochannels,of NRED poses a great challenge to achieving breakthroughs in energy conversion processes.This numerical study innovatively investigates the multi-factor coupling effect of three critical operational factors,including the nanochannel configuration,the temperature field,and the concentration difference,on the energy conversion processes of NRED.In this work,a dimensionless amplitude parameter s is introduced to emulate the randomly varied wall configuration of nanochannels that inherently occur in practical applications,thereby enhancing the realism and applicability of our analysis.Numerical results reveal that the application of a temperature gradient,which is oriented in opposition to the concentration gradient,enhances the ion transportation and selectivity simultaneously,leading to an enhancement in both output power and energy conversion efficiency.Additionally,the increased fluctuation of the nanochannel wall from s=0 to s=0.08 improves ion selectivity yet raises ion transport resistance,resulting in an enhancement in output power and energy conversion efficiency but a slight reduction in current.Furthermore,with increasing the concentration ratio cH/cL from 10 to 1000,either within a fixed temperature field or at a constant dimensionless amplitude,the maximumpower consistently attains its optimal value at a concentration ratio of 100 but the cation transfer number experiences amonotonic decrease across this entire range of concentration ratios.Finally,uponmodifying the operational parameters fromthe baseline condition of s=0,c_(H)/c_(L)=10,andΔT=0 K to the targetedconditionof s=0.08,c_(H)/c_(L)=50,andΔT=25 K,there is a concerted improvement observed in the open-circuit potential,short-circuit current,andmaximumpower,with respective increments of 8.86%,204.97%,and 232.01%,but a reduction in cation transfer number with a notable decrease of 15.37%.展开更多
Organic molecule passivation of perovskite surfaces has emerged as a promising strategy for efficient and durable perovskite solar cells(PSCs).While many materials have been reported,the optimization of molecular stru...Organic molecule passivation of perovskite surfaces has emerged as a promising strategy for efficient and durable perovskite solar cells(PSCs).While many materials have been reported,the optimization of molecular structure for the best passivation effect remains of significant interest but lacks sufficient study.In this work,we designed and synthesized three novel donor–acceptor-donor(D-A-D)type conjugated organic small molecules with varying alkyl chain lengths to regulate the interface between perovskite and Spiro-OMeTAD.Among them,the OSIT molecule,which features an n-octyl side chain of optimal length,demonstrated a balanced interfacial contact and interaction with the perovskite surface.Beyond the passivation effect of the electron-rich C=O group on undercoordinated Pb2+defects,OSIT optimizes energy level alignment and improves charge extraction by acting as an efficient hole transport channel.As a result,PSCs with OSIT interfacial layer achieved an exceptional efficiency of 25.48%and a high open-circuit voltage of 1.18 V.Furthermore,the durability of unencapsulated devices was significantly enhanced under various environmental conditions,maintaining 93.7%of their initial efficiency after 1000 h of maximum power point tracking in a nitrogen atmosphere.This study provides valuable insights into the rational design of D-A-D type materials for effective interface modification in PSCs.展开更多
This work describes a simple yet powerful scalable solution chemistry strategy to create back‐contact rich interfaces between substrates such as commercial transparent conducting fluorine‐doped tin oxide coated glas...This work describes a simple yet powerful scalable solution chemistry strategy to create back‐contact rich interfaces between substrates such as commercial transparent conducting fluorine‐doped tin oxide coated glass(FTO)and photoactive thin films such as hematite for low‐cost water oxidation reaction.High‐resolution electron microscopy(SEM,TEM,STEM),atomic force microscopy(AFM),elemental chemical mapping(EELS,EDS)and photoelectrochemical(PEC)investigations reveal that the mechanical stress,lattice mismatch,electron energy barrier,and voids between FTO and hematite at the back‐contact interface as well as short‐circuit and detrimental reaction between FTO and the electrolyte can be alleviated by engineering the chemical composition of the precursor solutions,thus increasing the overall efficiency of these low‐cost photoanodes for water oxidation reaction for a clean and sustainable generation of hydrogen from PEC water‐splitting.These findings are of significant importance to improve the charge collection efficiency by minimizing electron‐hole recombination observed at back‐contact interfaces and grain boundaries in mesoporous electrodes,thus improving the overall efficiency and scalability of low‐cost PEC water splitting devices.展开更多
In perovskite EuTiO_(3),the magnetic characteristics and magnetocaloric effect(MCE) can be flexibly regulated by converting the magnetism from antiferromagnetic to ferromagnetic.In the present work,a series of Eu(Ti,N...In perovskite EuTiO_(3),the magnetic characteristics and magnetocaloric effect(MCE) can be flexibly regulated by converting the magnetism from antiferromagnetic to ferromagnetic.In the present work,a series of Eu(Ti,Nb,Mn)O_(3) compounds,abbreviated as ETNMO for convenience of description,was fabricated and their crystallography,magnetism together with cryogenic magnetocaloric effects were systematically investigated.The crystallographic results demonstrate the cubic perovskite structure for all the compounds,with the space group of Pm3m.Two magnetic phase transitions are observed in these second-order phase transition(SOPT) materials.The joint substitution of elements Mn and Nb can considerably manipulate the magnetic phase transition process and magnetocaloric performance of the ETNMO compounds.As the Mn content increases,gradually widened-ΔS_(M)-T curves are obtained,and two peaks with a broad shoulder are observed in the-ΔS_(M)-T curves for Δμ_(0)H≤0-1 T.Under a field change of 0-5 T,the values of maximum magnetic entropy change(-ΔS_(M)^(max)) and refrigeration capacity(RC) are evaluated to be 34.7 J/(kg·K) and 364.9 J/kg for EuTi_(0.8625)Nb_(0.0625)Mn_(0.075)O_(3), 27.8 J/(kg·K) and367.6 J/kg for EuTi_(0.8375)Nb_(0.0625)Mn_(0.1)O_(3),23.2 J/(kg·K) and 369.2 J/kg for EuTi_(0.8125)Nb_(0.0625)Mn_(0.125)O_(3),17.1 J/(kg·K) and 357.6 J/kg for EuTi_(0.7875)Nb_(0.0625)Mn_(0.15)O_(3),respectively.The co nsiderable MCE parameters make the ETNMO compounds potential candidates for cryogenic magnetic refrigeration.展开更多
Developing high-performance aqueous Zn-ion batteries from sustainable biomass becomes increasingly vital for large-scale energy storage in the foreseeable future.Therefore,γ-MnO_(2) uniformly loaded on N-doped carbon...Developing high-performance aqueous Zn-ion batteries from sustainable biomass becomes increasingly vital for large-scale energy storage in the foreseeable future.Therefore,γ-MnO_(2) uniformly loaded on N-doped carbon derived from grapefruit peel is successfully fabricated in this work,and particularly the composite cathode with carbon carrier quality percentage of 20 wt%delivers the specific capacity of 391.2 mAh g^(−1)at 0.1 A g^(−1),outstanding cyclic stability of 92.17%after 3000 cycles at 5 A g^(−1),and remarkable energy density of 553.12 Wh kg^(−1) together with superior coulombic efficiency of~100%.Additionally,the cathodic biosafety is further explored specifically through in vitro cell toxicity experiments,which verifies its tremendous potential in the application of clinical medicine.Besides,Zinc ion energy storage mechanism of the cathode is mainly discussed from the aspects of Jahn–Teller effect and Mn domains distribution combined with theoretical analysis and experimental data.Thus,a novel perspective of the conversion from biomass waste to biocompatible Mn-based cathode is successfully developed.展开更多
Refrigeration in the liquid helium temperature range provides vital technological support for many scientific frontiers and engineering technologies.The considerable magnetocaloric effect(MCE)makes EuTiO_(3)a potentia...Refrigeration in the liquid helium temperature range provides vital technological support for many scientific frontiers and engineering technologies.The considerable magnetocaloric effect(MCE)makes EuTiO_(3)a potential candidate for magnetic refrigeration near liquid helium temperature.More interestingly,the magnetic transition from antiferromagnetism to ferromagnetism offers the possibility to tailor the magnetism and improve the MCE of this magnetic system.In this study,the magnetic properties and MCE of EuTi_(0.875)Zr_(0.125)O_(3)were systematically investigated by first-principles calculation and experiments.The substitution of Zr induces a significant lattice expansion and alters the electronic interactions,leading to a dominance of ferromagnetism in the compound.Remarkable low-field MCE performance has been achieved attributed to the enhanced ferromagnetism and low saturation field.Under the field change of 0-1 T,the maximum magnetic entropy change(−△S_(M)^(max))and adiabatic temperature change(△T_(ad)^(max))are 17.9 J kg^(-1)K^(-1)and 6.1 K,respectively.It is worth noting that the−△S_(M)^(max)of EuTi_(0.875)Zr_(0.125)O_(3)reaches 10.3 J kg^(-1)K^(-1)for a field change of 0-0.5 T,making it one of the best magnetocaloric materials ever reported operating in the liquid helium temperature range.展开更多
Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In th...Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically.展开更多
The magnetic properties,magnetic phase transition and magnetocaloric effects(MCE) of Er_(3)Si_(2)C_(2) compound were investigated based on theoretical calculations and experimental analysis.Based on the first principl...The magnetic properties,magnetic phase transition and magnetocaloric effects(MCE) of Er_(3)Si_(2)C_(2) compound were investigated based on theoretical calculations and experimental analysis.Based on the first principles calculations,the antiferromagnetic(AFM) ground state type in Er_(3)Si_(2)C_(2) compound was predicted and its electronic structure was investigated.The experimental results show that Ei_(3)Si_(2)C_(2) compound is an AFM compound with the Neel temperature(T_(N) of 7 K and undergoes a field-induced firstorder magnetic phase transition from AFM to ferromagnetic(FM) under magnetic fields exceeding 0.6 T at 2 K.The magnetic transition process of Er_(3)Si_(2)C_(2) compound was investigated and discussed.The values of the maximum magnetic entropy change(-ΔS_(M)^(max)) and the refrigeration capacity(RC) are 17 J/(kg·K)and 193 J/kg under changing magnetic fields of 0-5 T,respectively.As a potential cryogenic magnetic refrigerant,the Er_(3)Si_(2)C_(2) compound also provides an interesting research medium to study the magnetic phase transition process.展开更多
Because of the contradiction between the scale of new energy installations and the continuous load growth in the central and eastern regions of China,the balance problems of the electricity market are becoming increas...Because of the contradiction between the scale of new energy installations and the continuous load growth in the central and eastern regions of China,the balance problems of the electricity market are becoming increasingly prominent,and it is urgent to solve such problems through inter-provincial electricity spot markets.First,the development history and construction status of the inter-provincial electricity spot market are summarized;second,the mechanism design of the inter-provincial electricity spot market is sorted out in terms of the market operation framework,transaction declaration,and clearing methods;subsequently,the evaluation index system of the inter-provincial electricity spot market is constructed,including four themes of electricity mutual aid and support,new energy consumption,economic benefits of market-based allocation,and social benefits of market-based allocation;finally,the operation of the inter-provincial electricity spot market is comprehensively analyzed by the algorithm based on the market operation data of 2022,which proves the feasibility and practicality of the proposed index system.展开更多
The catalytic oxidation of volatile organic compounds(VOCs)is of considerable significance for the sustainable development of the chemical industry;thus,considerable efforts have been devoted to the exploration of eff...The catalytic oxidation of volatile organic compounds(VOCs)is of considerable significance for the sustainable development of the chemical industry;thus,considerable efforts have been devoted to the exploration of efficient catalysts for use in this reaction.In this regard,the development and utilization of single-atom catalysts(SACs)in VOCs decomposition is a rapidly expanding research area.SACs can be employed as potential catalysts for oxidizing VOC molecules due to their optimal utilization efficiency,unique atomic bonding structures,and unsaturated orbits.Progress has been achieved,while the challenges surrounding precise regulation of the microstructures of SACs for improving their low-temperature efficiency,stability,and product selectivity under practical conditions are remaining.Therefore,elucidating structure-performance relationships and establishing intrinsic modulating mechanisms are urgently required for guiding researchers on how to synthesize effective and stable functional SACs proactively.Herein,recent advances in the design and synthesis of functional SACs for application in the catalytic oxidation of VOCs are summarized.The experimental and theoretical studies revealing higher efficiency,stability,and selectivity of as-prepared functional SACs are being highlighted.Accordingly,the future perspectives in terms of promising catalysts with multi-sized composite active sites and the illustration of intrinsic mechanism are proposed.The rapid intelligent screening of applicable SACs and their industrial applications are also discussed.展开更多
The development of rechargeable magnesium(Mg) batteries is of practical significance to upgrade the electric energy storage devices due to exceptional capacity and abundant resources of Mg-metal anode.However,the reve...The development of rechargeable magnesium(Mg) batteries is of practical significance to upgrade the electric energy storage devices due to exceptional capacity and abundant resources of Mg-metal anode.However,the reversible Mg electrochemistry suffers from unsatisfied rate capability and lifespan,mainly caused by non-uniform distribution of electrodeposits.In this work,a fresh design concept of threedimensional carbon cloths scaffolds is proposed to overcome the uncontrollable Mg growth via homogenizing electric field and improving magnesiophilicity.A microscopic smooth and nitrogen-containing defective carbonaceous layer is constructed through a facile pyrolysis of ZIF8 on carbon cloths.As revealed by finite element simulation and DFT calculation results,the smooth surface endows with uniform electric field distribution and simultaneously the nitrogen-doping species enable good magnesiophilicity of scaffolds.The fine and uniform Mg nucleus as well as the inner electrodeposit behavior are also disclosed.As a result,an exceptional cycle life of 500 cycles at 4.0 mA cm^(-2) and 4.0 mA h cm^(-2) is firstly realized to our best knowledge.Besides,the functional scaffolds can be cycled for over 2200 h at 2.0 mA cm^(-2) under a normalized capacity of 5.0 mA h cm^(-2),far exceeding previous results.This work offers an effective approach to enable the full potential of carbon cloths-based scaffolds towards metal storage for next generation battery applications.展开更多
Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.Here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coup...Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.Here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by pyrolysis.The prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the reaction.Moreover,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation efficiency.Further,biochar can effectively promote cycling stability by limiting Fe leaching.This work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.展开更多
A mathematical model of multistage and multiphase reactions in flash smelting furnace, which based on the description of chemical reactions and reaction rate, is presented. In this model, main components of copper con...A mathematical model of multistage and multiphase reactions in flash smelting furnace, which based on the description of chemical reactions and reaction rate, is presented. In this model, main components of copper concentrate are represented as FeS 2 and CuFeS based on experiment, intermediate products are assumed to be S 2 and FeS, and the final products are assumed as FeS, FeO, SO 2, Cu 2S, FeO and FeO(SiO 2) 2. The model incorporates the transport of momentum, heat and mass, reaction kinetics between gas and particles, and reactions between gas and gas. The k-ε model is used to describe gas phase turbulence. The model uses the Eulerian approach for the gas flow equations and the Lagrangian approach for the particles. The coupling of gas and particle equations is performed through the particle source in cell(PSIC) method. Comparison between the model predictions and the plant measurements shows that the model has high reliability and accuracy.展开更多
文摘In order to increase the stability of the Mongolia power system, a single-phase automatic reclosing device (SPAR) was introduced on double-circuit power lines built with a size of 330 kV, operating on a voltage of 220 kV and a length of 250 km. These overhead power lines (L-213, L-214) connect the 220/110/35 kV “Songino” substation with the “Mandal” substation and form system networks. This paper presents the challenges encountered when implementing single-phase automatic reclosing (SPAR) devices and compares the changes in power system parameters before and after SPAR deployment for a long 220 kV line. Simulations and analyses were carried out using DIgSILENT PowerFactory software, focusing on rotor angle stability, and the overall impact on the power system during short-circuit faults. The evaluation also utilized measurement data from the Wide Area Monitoring System (WAMS) to compare system behavior pre- and post-implementation of SPAR. The findings reveal that SPAR significantly enhances system reliability and stability, effectively mitigating the risk of oscillations and stability loss triggered by short circuits. This improvement contributes to a more resilient power system, reducing the potential for disturbances caused by faults.
基金supported by Graduate Research and Innovation Program Project of Nanjing Institute of Technology(No.TB202517022).
文摘The configuration of a hybrid energy storage system(HESS)plays a pivotal role in mitigating wind power fluctuations and enabling primary frequency regulation,thereby enhancing the active power support capability of wind power integration systems.However,most existing studies on HESS capacity configuration overlook the selfrecovery control of the state of charge(SOC),creating challenges in sustaining capacity during long-term operation.This omission can impair frequency regulation performance,increase capacity requirements,and shorten battery lifespan.To address these challenges,this study proposes a bi-level planning–operation capacity configuration model that explicitly incorporates SOC self-recovery control.In the operation layer,a variable-baseline charging/discharging strategy is developed to restore SOC by balancing positive and negative energy over a 24-h period,with the goal of maximizing daily operational benefits.In the planning layer,the annualized net life-cycle cost of the HESS isminimized by configuring storage capacity based on feedback fromthe operation layer.Thetwo layers operate iteratively to achieve coordinated optimization of capacity sizing and control strategy.Case study results demonstrate the effectiveness of the proposed method.Compared with a configuration without considering SOC self-recovery,the proposed approach reduces the 1-min wind power fluctuation rate to 3.53%,lowers the mean squared frequency error to 0.000084,and decreases the annualized net life-cycle cost by 545,000 CNY/MWh.
基金Project supported by the National Key R&D Program of China(2021YFB3501204)the National Science Fund for Distinguished Young Scholars(51925605)+1 种基金the National Science Foundation for Excellent Young Scholars(52222107)the National Natural Science Foundation of China(52171195,52201036)。
文摘As one of the core components of a magnetic refrigerator,magnetic refrigeration materials are expected to have not only a considerable magnetocaloric effect but also excellent thermal conductivity.The poor thermal conductivity of many competitive oxide-based magnetic refrigerants,exemplified by EuTiO3-based compounds,acts as a major limitation to their practical application.Therefore,improving the thermal conductivity of magnetic refrigeration materials has become a research emphasis of magnetic refrigeration in recent years.In this work,a series of EuTiO_(3)(ETO)/Cu composites with different copper additives was prepared using a solid-phase reaction method by introducing appropriate amounts of copper powder.The influence of the introduction of copper on the phase composition,microstructure,thermal conductivity,and magnetocaloric effect of the composites was systematically investigated.Unexpectedly,the thermal conductivity of the composites is enhanced by up to 260%due to copper addition,accompanied by only a 5%decrease in magnetic entropy change and refrigerating capacity.Copper additive forms localized thermal conductive networks and promotes the densification process,resulting in significantly enhanced thermal conductivity of the composites.This work demonstrates the feasibility of improving the thermal conductivity of oxide-base d magnetic refrigeration materials by introducing highly thermally conductive substances.
基金Project supported by the National Key Research and Development Program of China(2021YFB3501204)the National Natural Science Foundation of China(52171054)+1 种基金the National Science Foundation for Distinguished Young Scholars(51925605)the National Science Foundation for Excellent Young Scholars(52222107)。
文摘Magnetic refrigeration(MR)technology is regarded as an ideal solution for cryogenic applications,relying on magnetocaloric materials which provide necessary chilling effect.A series of polycrystalline Tm_(1-x)Er_(x)Ni_(2)Si_(2)(x=0.2,0.4)compounds was synthesized,and their magnetic properties,magnetic phase transition together with magnetocaloric effect(MCE)were studied.The Tm_(1-x)Er_(x)Ni_(2)Si_(2)(x=0.2,0.4)compounds display a field-induced metamagnetic transition from antiferromagnetic(AFM)to ferromagnetism(FM)in excess of 0.2 T,respectively.Meanwhile,the AFM ground state is unstable.Under the field change of 0-2 T,the values of maximal magnetic entropy change(-ΔS_(M)^(max))and refrigerant capacity(RC)for Tm_(0.8)Er_(0.2)Ni_(2)Si_(2)compound are 17.9 J/(kg·K)and 83.5 J/kg,respectively.The large reversible MCE under low magnetic fields(≤2 T)indicates that Tm_(0.8)Er_(0.2)Ni_(2)Si_(2)compound can serve as potential candidate materials for cryogenic magnetic refrigeration.
基金Project supported by the National Key Research and Development Program of China(2022YFB3505101)the National Science Foundation for Excellent Young Scholars(52222107)+2 种基金the National Science Foundation for Distinguished Young Scholars(51925605)the National Natural Science Foundation of China(52171195)the Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(E055B002)。
文摘Frustrated lanthanide oxides with dense magnetic lattice and suppressed ordering temperature have potential applications in cryogenic magnetic refrigeration.Herein,the crystal structure,magnetic properties,magnetic phase transition(MPT)together with magnetocaloric effect(MCE)of LnOF(Ln=Gd,Dy,Ho,and Er)compounds were investigated.Crystallographic study shows that these compounds crystallize in the centrosymmetric space group R3m with an ideal triangular lattice.No long-range magnetic ordering is observed above 2 K for LnOF(Ln=Gd,Ho,and Er).However,DyOF compound undergoes an MPT from paramagnetic(PM)to antiferromagnetic(AFM)at the Neel temperature(TN≈4 K).Considerable reversible MCE is observed in these triangular-lattice compounds.Under the magnetic field change(μ0ΔH)of 0-2 T,the maximum values of magnetic entropy change(-ΔSMmax)of them are 6.1,9.4,12.7,and 14.1 J/(kg·K),respectively.Interestingly,the value of ErOF with Ising-like spin is 2.3 times that of GdOF,which provides an approach for exploring magnetic refrigerants with excellent low-field cryogenic magnetocaloric effect.
基金supported by National Natural Science Foundation of China(52477101)Natural Science Foundation of Jiangsu Province(BK20210932).
文摘With the intensification of the energy crisis and the worsening greenhouse effect,the development of sustainable integrated energy systems(IES)has become a crucial direction for energy transition.In this context,this paper proposes a low-carbon economic dispatch strategy under the green hydrogen certificate trading(GHCT)and the ladder-type carbon emission trading(CET)mechanism,enabling the coordinated utilization of green and blue hydrogen.Specifically,a proton exchange membrane electrolyzer(PEME)model that accounts for dynamic efficiency characteristics,and a steam methane reforming(SMR)model incorporating waste heat recovery,are developed.Based on these models,a hydrogen production–storage–utilization framework is established to enable the coordinated deployment of green and blue hydrogen.Furthermore,the gas turbine(GT)unit are retrofitted using oxygenenriched combustion carbon capture(OCC)technology,wherein the oxygen produced by PEME is employed to create an oxygen-enriched combustion environment.This approach reduces energy waste and facilitates low-carbon power generation.In addition,the GHCT mechanism is integrated into the system alongside the ladder-type CET mechanism,and their complementary effects are investigated.A comprehensive optimization model is then formulated to simultaneously achieve carbon reduction and economic efficiency across the system.Case study results show that the proposed strategy reduces wind curtailment by 7.77%,carbon emissions by 65.98%,and total cost by 12.57%.This study offers theoretical reference for the low-carbon,economic,and efficient operation of future energy systems.
基金supported by the National Key Research and Development Program of China(2022YFB3803600)the National Natural Science Foundation of China(52276212)+4 种基金the Natural Science Foundation of Jiangsu Province(BK20231211)the Suzhou Science and Technology Program(SYG202101)the Key Research and Development Program in Shaanxi Province of China(2023-YBGY-300)the Zhuhai Innovation and Entrepreneurship Team Project(2120004000225)the China Fundamental Research Funds for the Central Universities。
文摘Recent interest in photocatalytic water splitting has intensified the demand in the development of photocatalysts capable of harnessing the full solar-spectrum.This study introduces a novel WO_(x)/ZnIn_(2)S_(4)Zscheme heterojunction,prepared by depositing ZnIn_(2)S_(4)(ZIS)nanosheets onto WO_(x)nanorods,enabling efficient photothermal-coupled photocatalytic H_(2)evolution.The success relies on the engineered oxygen vacancies within WO_(x)nanorods,which not only confer excellent photothermal properties lowering the reaction barrier but also create defect levels in WO_(x)facilitating Z-scheme electron transfer from these levels to the valence band of ZIS.Consequently,the optimized WO_(x)/ZIS heterojunction exhibits a remarkable H_(2)evolution rate of 33.91 mmol h^(-1)g^(-1)with an apparent quantum efficiency of 23.6%at 400 nm.This study provides a new strategy for developing efficient Z-scheme heterojunctions with broadspectrum solar hydrogen production capabilities.
基金funded by the National Natural Science Foundation of China[52106246]the Postgraduate Research&Practice innovation Program of Jiangsu Province[KYCX24_1641].
文摘Based on the rapid advancements in nanomaterials and nanotechnology,the Nanofluidic Reverse Electrodialysis(NRED)has attracted significant attention as an innovative and promising energy conversion strategy for extracting sustainable and clean energy fromthe salinity gradient energy.However,the scarcity of research investigating the intricate multi-factor coupling effects on the energy conversion performance,especially the trade-offs between ion selectivity and mass transfer in nanochannels,of NRED poses a great challenge to achieving breakthroughs in energy conversion processes.This numerical study innovatively investigates the multi-factor coupling effect of three critical operational factors,including the nanochannel configuration,the temperature field,and the concentration difference,on the energy conversion processes of NRED.In this work,a dimensionless amplitude parameter s is introduced to emulate the randomly varied wall configuration of nanochannels that inherently occur in practical applications,thereby enhancing the realism and applicability of our analysis.Numerical results reveal that the application of a temperature gradient,which is oriented in opposition to the concentration gradient,enhances the ion transportation and selectivity simultaneously,leading to an enhancement in both output power and energy conversion efficiency.Additionally,the increased fluctuation of the nanochannel wall from s=0 to s=0.08 improves ion selectivity yet raises ion transport resistance,resulting in an enhancement in output power and energy conversion efficiency but a slight reduction in current.Furthermore,with increasing the concentration ratio cH/cL from 10 to 1000,either within a fixed temperature field or at a constant dimensionless amplitude,the maximumpower consistently attains its optimal value at a concentration ratio of 100 but the cation transfer number experiences amonotonic decrease across this entire range of concentration ratios.Finally,uponmodifying the operational parameters fromthe baseline condition of s=0,c_(H)/c_(L)=10,andΔT=0 K to the targetedconditionof s=0.08,c_(H)/c_(L)=50,andΔT=25 K,there is a concerted improvement observed in the open-circuit potential,short-circuit current,andmaximumpower,with respective increments of 8.86%,204.97%,and 232.01%,but a reduction in cation transfer number with a notable decrease of 15.37%.
基金supported by the National Natural Science Foundation of China(22179053,22279046)Natural Science Excellent Youth Foundation of Jiangsu Provincial(BK20220112)+1 种基金Special Foundation for Carbon Peak Carbon Neutralization Technology Innovation Program of Jiangsu Province(BE2022026-2)JSPS KAKENHI(20K15385,20H02817,and 24H00486)。
文摘Organic molecule passivation of perovskite surfaces has emerged as a promising strategy for efficient and durable perovskite solar cells(PSCs).While many materials have been reported,the optimization of molecular structure for the best passivation effect remains of significant interest but lacks sufficient study.In this work,we designed and synthesized three novel donor–acceptor-donor(D-A-D)type conjugated organic small molecules with varying alkyl chain lengths to regulate the interface between perovskite and Spiro-OMeTAD.Among them,the OSIT molecule,which features an n-octyl side chain of optimal length,demonstrated a balanced interfacial contact and interaction with the perovskite surface.Beyond the passivation effect of the electron-rich C=O group on undercoordinated Pb2+defects,OSIT optimizes energy level alignment and improves charge extraction by acting as an efficient hole transport channel.As a result,PSCs with OSIT interfacial layer achieved an exceptional efficiency of 25.48%and a high open-circuit voltage of 1.18 V.Furthermore,the durability of unencapsulated devices was significantly enhanced under various environmental conditions,maintaining 93.7%of their initial efficiency after 1000 h of maximum power point tracking in a nitrogen atmosphere.This study provides valuable insights into the rational design of D-A-D type materials for effective interface modification in PSCs.
基金supported by CNPq,CAPES,FAPESP(2017/02317-2),FAPESP(2017/11986-5)Shell and the strategic importance of the support given by ANP(Brazil’s National Oil,Natural Gas and Biofuels Agency)through the R&D levy regulation+2 种基金PRH49/UFABC-ANP for the fellowshipthe National Natural Science Foundation of China(NSFC)the Outstanding Talent Program of Shaanxi Province as well as FAPESP(2017/11986-5)
文摘This work describes a simple yet powerful scalable solution chemistry strategy to create back‐contact rich interfaces between substrates such as commercial transparent conducting fluorine‐doped tin oxide coated glass(FTO)and photoactive thin films such as hematite for low‐cost water oxidation reaction.High‐resolution electron microscopy(SEM,TEM,STEM),atomic force microscopy(AFM),elemental chemical mapping(EELS,EDS)and photoelectrochemical(PEC)investigations reveal that the mechanical stress,lattice mismatch,electron energy barrier,and voids between FTO and hematite at the back‐contact interface as well as short‐circuit and detrimental reaction between FTO and the electrolyte can be alleviated by engineering the chemical composition of the precursor solutions,thus increasing the overall efficiency of these low‐cost photoanodes for water oxidation reaction for a clean and sustainable generation of hydrogen from PEC water‐splitting.These findings are of significant importance to improve the charge collection efficiency by minimizing electron‐hole recombination observed at back‐contact interfaces and grain boundaries in mesoporous electrodes,thus improving the overall efficiency and scalability of low‐cost PEC water splitting devices.
基金Research Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences (No.E055B002) for providing financial support。
文摘In perovskite EuTiO_(3),the magnetic characteristics and magnetocaloric effect(MCE) can be flexibly regulated by converting the magnetism from antiferromagnetic to ferromagnetic.In the present work,a series of Eu(Ti,Nb,Mn)O_(3) compounds,abbreviated as ETNMO for convenience of description,was fabricated and their crystallography,magnetism together with cryogenic magnetocaloric effects were systematically investigated.The crystallographic results demonstrate the cubic perovskite structure for all the compounds,with the space group of Pm3m.Two magnetic phase transitions are observed in these second-order phase transition(SOPT) materials.The joint substitution of elements Mn and Nb can considerably manipulate the magnetic phase transition process and magnetocaloric performance of the ETNMO compounds.As the Mn content increases,gradually widened-ΔS_(M)-T curves are obtained,and two peaks with a broad shoulder are observed in the-ΔS_(M)-T curves for Δμ_(0)H≤0-1 T.Under a field change of 0-5 T,the values of maximum magnetic entropy change(-ΔS_(M)^(max)) and refrigeration capacity(RC) are evaluated to be 34.7 J/(kg·K) and 364.9 J/kg for EuTi_(0.8625)Nb_(0.0625)Mn_(0.075)O_(3), 27.8 J/(kg·K) and367.6 J/kg for EuTi_(0.8375)Nb_(0.0625)Mn_(0.1)O_(3),23.2 J/(kg·K) and 369.2 J/kg for EuTi_(0.8125)Nb_(0.0625)Mn_(0.125)O_(3),17.1 J/(kg·K) and 357.6 J/kg for EuTi_(0.7875)Nb_(0.0625)Mn_(0.15)O_(3),respectively.The co nsiderable MCE parameters make the ETNMO compounds potential candidates for cryogenic magnetic refrigeration.
基金supported by the National Natural Science Foundation of China[Grant no.51821004].
文摘Developing high-performance aqueous Zn-ion batteries from sustainable biomass becomes increasingly vital for large-scale energy storage in the foreseeable future.Therefore,γ-MnO_(2) uniformly loaded on N-doped carbon derived from grapefruit peel is successfully fabricated in this work,and particularly the composite cathode with carbon carrier quality percentage of 20 wt%delivers the specific capacity of 391.2 mAh g^(−1)at 0.1 A g^(−1),outstanding cyclic stability of 92.17%after 3000 cycles at 5 A g^(−1),and remarkable energy density of 553.12 Wh kg^(−1) together with superior coulombic efficiency of~100%.Additionally,the cathodic biosafety is further explored specifically through in vitro cell toxicity experiments,which verifies its tremendous potential in the application of clinical medicine.Besides,Zinc ion energy storage mechanism of the cathode is mainly discussed from the aspects of Jahn–Teller effect and Mn domains distribution combined with theoretical analysis and experimental data.Thus,a novel perspective of the conversion from biomass waste to biocompatible Mn-based cathode is successfully developed.
基金supported by the National Key R&D Program of China(No.2021YFB3501204)the National Science Foundation for Excellent Young Scholars(No.52222107)+1 种基金the National Science Fund for Distinguished Young Scholars(No.51925605)the National Natural Science Foundation of China(No.52171195).
文摘Refrigeration in the liquid helium temperature range provides vital technological support for many scientific frontiers and engineering technologies.The considerable magnetocaloric effect(MCE)makes EuTiO_(3)a potential candidate for magnetic refrigeration near liquid helium temperature.More interestingly,the magnetic transition from antiferromagnetism to ferromagnetism offers the possibility to tailor the magnetism and improve the MCE of this magnetic system.In this study,the magnetic properties and MCE of EuTi_(0.875)Zr_(0.125)O_(3)were systematically investigated by first-principles calculation and experiments.The substitution of Zr induces a significant lattice expansion and alters the electronic interactions,leading to a dominance of ferromagnetism in the compound.Remarkable low-field MCE performance has been achieved attributed to the enhanced ferromagnetism and low saturation field.Under the field change of 0-1 T,the maximum magnetic entropy change(−△S_(M)^(max))and adiabatic temperature change(△T_(ad)^(max))are 17.9 J kg^(-1)K^(-1)and 6.1 K,respectively.It is worth noting that the−△S_(M)^(max)of EuTi_(0.875)Zr_(0.125)O_(3)reaches 10.3 J kg^(-1)K^(-1)for a field change of 0-0.5 T,making it one of the best magnetocaloric materials ever reported operating in the liquid helium temperature range.
基金National Key R&D Program of China,Grant/Award Number:2021YFF0500700Fundamental Research Funds for the Central Universities,Grant/Award Numbers:30921013103,30920041113+1 种基金Jiangsu Natural Science Foundation,Grant/Award Number:BK20190460National Natural Science Foundation of China,Grant/Award Numbers:51888103,52006105,92163124。
文摘Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically.
基金supported by the National Key Research and Development Program of China (2021YFB3501204)the National Science Foundation for Excellent Young Scholars (52222107)+2 种基金the National Science Foundation for Distinguished Young Scholars (51925605)the National Natural Science Foundation of China (52171195)Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences (E055B002)。
文摘The magnetic properties,magnetic phase transition and magnetocaloric effects(MCE) of Er_(3)Si_(2)C_(2) compound were investigated based on theoretical calculations and experimental analysis.Based on the first principles calculations,the antiferromagnetic(AFM) ground state type in Er_(3)Si_(2)C_(2) compound was predicted and its electronic structure was investigated.The experimental results show that Ei_(3)Si_(2)C_(2) compound is an AFM compound with the Neel temperature(T_(N) of 7 K and undergoes a field-induced firstorder magnetic phase transition from AFM to ferromagnetic(FM) under magnetic fields exceeding 0.6 T at 2 K.The magnetic transition process of Er_(3)Si_(2)C_(2) compound was investigated and discussed.The values of the maximum magnetic entropy change(-ΔS_(M)^(max)) and the refrigeration capacity(RC) are 17 J/(kg·K)and 193 J/kg under changing magnetic fields of 0-5 T,respectively.As a potential cryogenic magnetic refrigerant,the Er_(3)Si_(2)C_(2) compound also provides an interesting research medium to study the magnetic phase transition process.
基金State Grid Jibei Electric Power Company Limited(no.SGJBJY00GPJS2310051)Natural Science Foundation of Beijing Municipality(no.9242015).
文摘Because of the contradiction between the scale of new energy installations and the continuous load growth in the central and eastern regions of China,the balance problems of the electricity market are becoming increasingly prominent,and it is urgent to solve such problems through inter-provincial electricity spot markets.First,the development history and construction status of the inter-provincial electricity spot market are summarized;second,the mechanism design of the inter-provincial electricity spot market is sorted out in terms of the market operation framework,transaction declaration,and clearing methods;subsequently,the evaluation index system of the inter-provincial electricity spot market is constructed,including four themes of electricity mutual aid and support,new energy consumption,economic benefits of market-based allocation,and social benefits of market-based allocation;finally,the operation of the inter-provincial electricity spot market is comprehensively analyzed by the algorithm based on the market operation data of 2022,which proves the feasibility and practicality of the proposed index system.
基金financially supported by the National Natural Science Foundation of China(Nos.22276145,2187613921922606)+1 种基金National Key R&D Program of China(No.2022YFB4101500)China Postdoctoral Science Foundation(No.2023M732783)。
文摘The catalytic oxidation of volatile organic compounds(VOCs)is of considerable significance for the sustainable development of the chemical industry;thus,considerable efforts have been devoted to the exploration of efficient catalysts for use in this reaction.In this regard,the development and utilization of single-atom catalysts(SACs)in VOCs decomposition is a rapidly expanding research area.SACs can be employed as potential catalysts for oxidizing VOC molecules due to their optimal utilization efficiency,unique atomic bonding structures,and unsaturated orbits.Progress has been achieved,while the challenges surrounding precise regulation of the microstructures of SACs for improving their low-temperature efficiency,stability,and product selectivity under practical conditions are remaining.Therefore,elucidating structure-performance relationships and establishing intrinsic modulating mechanisms are urgently required for guiding researchers on how to synthesize effective and stable functional SACs proactively.Herein,recent advances in the design and synthesis of functional SACs for application in the catalytic oxidation of VOCs are summarized.The experimental and theoretical studies revealing higher efficiency,stability,and selectivity of as-prepared functional SACs are being highlighted.Accordingly,the future perspectives in terms of promising catalysts with multi-sized composite active sites and the illustration of intrinsic mechanism are proposed.The rapid intelligent screening of applicable SACs and their industrial applications are also discussed.
基金supported by the National Natural Science Foundation of China(51972187,22279068,52374306)the Natural Science Foundation of Shandong Province(ZR2021QE166)Qingdao New Energy Shandong Laboratory Open Project(QNESL OP202312)。
文摘The development of rechargeable magnesium(Mg) batteries is of practical significance to upgrade the electric energy storage devices due to exceptional capacity and abundant resources of Mg-metal anode.However,the reversible Mg electrochemistry suffers from unsatisfied rate capability and lifespan,mainly caused by non-uniform distribution of electrodeposits.In this work,a fresh design concept of threedimensional carbon cloths scaffolds is proposed to overcome the uncontrollable Mg growth via homogenizing electric field and improving magnesiophilicity.A microscopic smooth and nitrogen-containing defective carbonaceous layer is constructed through a facile pyrolysis of ZIF8 on carbon cloths.As revealed by finite element simulation and DFT calculation results,the smooth surface endows with uniform electric field distribution and simultaneously the nitrogen-doping species enable good magnesiophilicity of scaffolds.The fine and uniform Mg nucleus as well as the inner electrodeposit behavior are also disclosed.As a result,an exceptional cycle life of 500 cycles at 4.0 mA cm^(-2) and 4.0 mA h cm^(-2) is firstly realized to our best knowledge.Besides,the functional scaffolds can be cycled for over 2200 h at 2.0 mA cm^(-2) under a normalized capacity of 5.0 mA h cm^(-2),far exceeding previous results.This work offers an effective approach to enable the full potential of carbon cloths-based scaffolds towards metal storage for next generation battery applications.
基金financially supported by the National Natural Science Foundation of China (Nos.21876139 and 21922606)Yulin Science and Technology Project of China (No.CXY2021-134)。
文摘Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater treatment.Here,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by pyrolysis.The prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the reaction.Moreover,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation efficiency.Further,biochar can effectively promote cycling stability by limiting Fe leaching.This work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.
文摘A mathematical model of multistage and multiphase reactions in flash smelting furnace, which based on the description of chemical reactions and reaction rate, is presented. In this model, main components of copper concentrate are represented as FeS 2 and CuFeS based on experiment, intermediate products are assumed to be S 2 and FeS, and the final products are assumed as FeS, FeO, SO 2, Cu 2S, FeO and FeO(SiO 2) 2. The model incorporates the transport of momentum, heat and mass, reaction kinetics between gas and particles, and reactions between gas and gas. The k-ε model is used to describe gas phase turbulence. The model uses the Eulerian approach for the gas flow equations and the Lagrangian approach for the particles. The coupling of gas and particle equations is performed through the particle source in cell(PSIC) method. Comparison between the model predictions and the plant measurements shows that the model has high reliability and accuracy.
