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Self-balancing Three-phase Five-level Inverter with Reduced DC Bus Voltage
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作者 Wenyuan Zhang Hongliang Wang +3 位作者 Xiaonan Zhu Hanzhe Wang Xiaojun Deng Xiumei Yue 《CSEE Journal of Power and Energy Systems》 2026年第1期377-389,共13页
Switched-capacitor/flying capacitor(FC)based multilevel converters have been gaining higher attention for their voltage-boosting ability.This feature makes them an attractive solution for renewable energy systems,such... Switched-capacitor/flying capacitor(FC)based multilevel converters have been gaining higher attention for their voltage-boosting ability.This feature makes them an attractive solution for renewable energy systems,such as low-voltage input photovoltaic power systems and electric vehicle systems.However,they usually require more high voltage rating switches and flying capacitors along with boosting capability.Furthermore,they suffer from high pulse currents at the switching transients.Aiming to solve these issues,this article proposes a new self-balancing three-phase five-level inverter based on the switched-capacitor(5L-SCTPNPC),which reduces the dc voltage requirement.The number of active switches is relatively smaller and seven active switches are required per phase.Especially,a soft-charging circuit for FC is designed to limit the impulse charging current.Compared to conventional multilevel inverters,the proposed five-level inverter reduces dc bus voltage by 50%.Significantly,the voltage stress of FC and the switches in parallel with FC are all reduced by 50%in comparison with some existing similar boosting five-level active-neutral-point-clamped(5L-BANPC)inverters.The operating principles,modulation strategy,and the design of the FC and charging inductor are provided in detailly.A comprehensive comparison study has been made to highlight the merits of the proposed inverter.Finally,the simulations and experiments validate the feasibility of the proposed topology. 展开更多
关键词 DC voltage utilization multilevel converters SWITCHED-CAPACITOR three-phase systems
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A Cosolvent Electrolyte Boosting H_(2)S Decomposition via Three-Phase Indirect Electrolysis
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作者 Gang Liu Yanzhen Wang +5 位作者 Hongling Duan Chunmin Song Wei Xia He Liu Fei Yu Aijun Guo 《Energy & Environmental Materials》 2026年第1期263-274,共12页
Renewable electricity-driven production of value-added sulfur and H_(2)via electrocatalytic H_(2)S decomposition represents a sustainable route to conventional thermocatalysis.Both the electrocatalyst and electrolyte ... Renewable electricity-driven production of value-added sulfur and H_(2)via electrocatalytic H_(2)S decomposition represents a sustainable route to conventional thermocatalysis.Both the electrocatalyst and electrolyte solution strongly impact the H_(2)S decomposition performance.Despite significant progress in developing sophisticated electrocatalysts,a well-designed electrolyte solution in conjunction with industrial catalysts is an attractive strategy to advance the industrialization process of electrocatalytic H_(2)S decomposition,but remains unexplored.Here,for the first time,we design a solid-liquid-gas three-phase indirect electrolysis system based on a kind of CS_(2)-N electrolyte solution and Ni-Mo_(2)C that can efficiently enable H_(2)S decomposition into valuable H_(2)and sulfur.Specifically,the solid-phase Ni-Mo_(2)C as a heterogeneous redox mediator presents excellent electrocatalytic efficiency for the H_(2)S removal efficiency of up to 99%,and the formation of liquid-phase sulfur product(CS_(2)-N electrolyte solution dissolves sulfur,yield up to 95%)with the generation of gas-phase H_(2)product(~1.32 mL min^(-1)),resulting in an interesting three-phase indirect electrolysis system.Remarkably,it enables the scale-up production(~6 g in a batch experiment)of sulfur with continuous operation for 120 h without attenuation.This work may inaugurate a new electrocatalytic H_(2)S decomposition avenue to explore porous metal materials and electrolyte systems in simultaneous production of value-added sulfur and H_(2). 展开更多
关键词 H_(2) H_(2)S decomposition indirect electrocatalysis sulfur three-phase system
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Effect of ladle shroud immersion depth on unsteady three-phase flow in continuous casting tundish during ladle change-over process
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作者 Yu-Chao Yao Zhong-Qiu Liu +3 位作者 Yu-Ze Wei Ning Wang Jun Yang Bao-Kuan Li 《Journal of Iron and Steel Research International》 2026年第1期443-457,共15页
The transient phenomena of re-oxidation and slag entrapment occurring in the tundish during the ladle change-over process have been proven detrimental to clean steel production.Therefore,an unsteady three-phase turbul... The transient phenomena of re-oxidation and slag entrapment occurring in the tundish during the ladle change-over process have been proven detrimental to clean steel production.Therefore,an unsteady three-phase turbulence model,coupling velocity,temperature,and phase field was established to study the effect of the ladle shroud immersion depth on the slag eye formation,slag entrainment,slag dragging,air dragging,and flow characteristics during the ladle change-over process of a two-strand tundish.The results showed that reducing the immersion depth decreases the high-velocity region area under the slag layer in the quasi-steady process.During the emptying stage,as the molten bath level gradually decreases,the outlet temperature exhibits a trend of initially decreasing and subsequently increasing across all three shroud immersion depths.However,under a 210 mm shroud immersion depth,molten slag and air are dragged into the shroud,forming slag droplets and causing significant fluctuations,with a maximum scalar velocity of 0.0764 m/s at the monitoring point.In the filling stage,air and molten slag are dragged into the molten bath,forming bubbles and slag droplets at an immersion depth of 210 mm.Bubbles are observed within the molten slag layer,which can readily cause an emulsification phenomenon,making it easier to be dragged as slag droplets.Additionally,the slag eye area measured under 210 mm immersion depth at 45 s is 0.303 m^(2),while the maximum scalar velocity of 2.4259 m/s is detected at 12 s.At an immersion depth of 360 mm,the average area of the slag eye is minimized to 0.06268 m2,with corresponding variances of 0.006753,representing the optimal immersion depth. 展开更多
关键词 Continuous casting tundish Ladle change-over Ladle shroud Immersion depth three-phase flow Unsteady state
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Deciphering engineering principle of three-phase interface for advanced gas-involved electrochemical reactions 被引量:5
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作者 Yanzheng He Sisi Liu +3 位作者 Mengfan Wang Qiyang Cheng Tao Qian Chenglin Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期302-323,I0008,共23页
As an alternative to conventional energy conversion and storage reactions,gas-involved electrochemical reactions,including the carbon dioxide reduction reaction(CO_(2)RR),nitrogen reduction reaction(NRR)and hydrogen e... As an alternative to conventional energy conversion and storage reactions,gas-involved electrochemical reactions,including the carbon dioxide reduction reaction(CO_(2)RR),nitrogen reduction reaction(NRR)and hydrogen evolution reaction(HER),have become an emerging research direction and have gained increasing attention due to their advantages of environmental friendliness and sustainability.Various studies have been designed to accelerate sluggish kinetics but with limited results.Most of them promote the reaction by modulating the intrinsic properties of the catalyst,ignoring the synergistic effect of the reaction as a whole.Due to the introduction of gas,traditional liquid-solid two-phase reactions are no longer applicable to future research.Since gas-involved electrochemical reactions mostly occur at the junctions of gaseous reactants,liquid electrolytes and solid catalysts,the focus of future research on reaction kinetics should gradually shift to three-phase reaction interfaces.In this review,we briefly introduce the formation and constraints of the three-phase interface and propose three criteria to judge its merit,namely,the active site,mass diffusion and electron mass transfer.Subsequently,a series of modulation methods and relevant works are discussed in detail from the three improvement directions of‘exposing more active sites,promoting mass diffusion and accelerating electron transfer’.Definitively,we provide farsighted insights into the understanding and research of three-phase interfaces in the future and point out the possible development direction of future regulatory methods,hoping that this review can broaden the future applications of the three-phase interface,including but not limited to gas-involved electrochemical reactions. 展开更多
关键词 three-phase reaction Surface reactions Mass diffusion Electron transfer Gas-involved electrochemical reactions
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Four-level SVPWM Strategy of Dual Three-phase Open-winding PMSM Drive
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作者 Haowen Jiang Xueqing Wang +3 位作者 Xinyu Yan Dianxun Xiao Xiaobao Yang Zheng Wang 《CES Transactions on Electrical Machines and Systems》 2025年第3期257-267,共11页
To achieve high power rating and low current harmonics of motor drive,this paper develops a dual three-phase open-winding permanent magnet synchronous motor(DTP-OW-PMSM)drive with the DC-link voltage ratio of 2:1:1.Ba... To achieve high power rating and low current harmonics of motor drive,this paper develops a dual three-phase open-winding permanent magnet synchronous motor(DTP-OW-PMSM)drive with the DC-link voltage ratio of 2:1:1.Based on this topology,this paper proposes a DTP four-level space vector pulse width modulation(DTP-FL SVPWM)strategy.First,two identical three-phase four-level space vector diagrams are constructed and divided.Then,three adjacent vectors nearest to the reference vector in each diagram are selected for the vector synthesis to guarantee high modulation precision and low switching frequency.Furthermore,to avoid the modulation error caused by the voltage deviation,the proposed DTP-FL SVPWM strategy is further optimized through unified duty ratio compensation(UDRC).The effectiveness of the proposed strategy is verified through experiments. 展开更多
关键词 Dual three-phase open-winding permanent magnet synchronous motor(DTP-OW-PMSM) Dual three-phase four-level(DTP-FL)modulation High modulation precision Unified duty ratio compensation(UDRC)
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Research on the Application of Three-Phase VIENNA Topology in High-Power Switching Power Supplies
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作者 Bai Fusheng 《Journal of Electronic Research and Application》 2025年第6期139-147,共9页
The growing demand for efficient high-power switching power supplies has spurred interest in advanced topologies.The three-phase VIENNA converter stands out for its high power factor,simplified structure,and robust pe... The growing demand for efficient high-power switching power supplies has spurred interest in advanced topologies.The three-phase VIENNA converter stands out for its high power factor,simplified structure,and robust performance.Current research focuses on its operational principles,control strategies,and behavior under various load conditions.Key considerations include component selection,thermal management,and EMI/EMC optimization.This topology finds applications across renewable energy systems,industrial equipment,telecommunications,and electric vehicle charging infrastructures.Comparative analyses with alternative topologies and cost-benefit evaluations are also addressed.Future developments are expected to emphasize the integration of wide-bandgap devices and advancements in digital control techniques to further enhance efficiency and system performance. 展开更多
关键词 three-phase VIENNA topology High-power switching power supplies Component selection
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情感商品与版权迷思:B站Reaction视频“充电专场”的实践逻辑与风险批判
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作者 王妍 《科技传播》 2026年第3期160-164,169,共6页
采用参与式观察和半结构化访谈的方法,探究B站Reaction视频(反应视频)“充电专场”模式的实践逻辑。研究发现,“充电专场”中UP主的情感劳动在追求情绪价值输出的同时面临情感异化风险,付费模式也重构了UP主与粉丝的关系,情感连接呈现... 采用参与式观察和半结构化访谈的方法,探究B站Reaction视频(反应视频)“充电专场”模式的实践逻辑。研究发现,“充电专场”中UP主的情感劳动在追求情绪价值输出的同时面临情感异化风险,付费模式也重构了UP主与粉丝的关系,情感连接呈现出工具化倾向,且该模式处于版权管理的灰色地带,UP主的规避策略无法从根本上化解系统性风险。“充电专场”是平台资本、UP主生计与粉丝情感需求共同作用下的产物,它虽提供了灵活的生计可能,但也预示着情感深度商品化与数字劳动不稳定的未来图景。 展开更多
关键词 reaction视频 充电专场 情感劳动 版权风险 情绪消费
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Review of Control Techniques for Dual Three-phase PMSM Drives with Low Carrier Ratios
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作者 Minrui Gu Zheng Wang +3 位作者 Ming Cheng Weifeng Su Linyue Shang Po Liu 《CES Transactions on Electrical Machines and Systems》 2025年第2期177-188,共12页
The dual three-phase PMSM(DTP-PMSM)drives have received wide attention at high-power high-efficiency applications due to their merits of high output current ability and copper-loss-free field excitation.Meanwhile,the ... The dual three-phase PMSM(DTP-PMSM)drives have received wide attention at high-power high-efficiency applications due to their merits of high output current ability and copper-loss-free field excitation.Meanwhile,the DTPPMSM drive provides higher fault-tolerant capability for highreliability applications,e.g.,pumps and actuators in aircraft.For high-power drives with limited switching frequencies and highspeed drives with large fundamental frequencies,the ratio of switching frequency to fundamental frequency,i.e.,the carrier ratio,is usually below 15,which would significantly degrade the control performance.The purpose of this paper is to review the recent work on the modulation and control schemes for improving the operation performance of DTP-PMSM drives with low carrier ratios.Specifically,three categories of methods,i.e.,the space vector modulation based control,the model predictive control(MPC),and the optimized pulse pattern(OPP)based control are reviewed with principles and performance.In addition,brief discussions regarding the comparison and future trends are presented for low-carrier-ratio(LCR)modulation and control schemes of DTP-PMSM drives. 展开更多
关键词 Dual three-phase permanent magnet synchronous motor(DTP-PMSM) Low-carrier-ratio(LCR) Complex vector control Model predictive control(MPC) Optimized pulse pattern(OPP)
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Synthesis ofα,β-Disubstituted Acrylates via PPh_(3)-Catalyzed Ring-Opening Addition Reaction of Cyclopropenones with Alkyl Bromides at Room Temperature
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作者 Xu Cheng Peng Tao +5 位作者 Zhou Mengyuan Liu Minglin Huang Xiaoqing Wang Yongfeng Liu Zheng Yin Guodong 《有机化学》 北大核心 2026年第1期279-288,共10页
A PPh_(3)-catalyzed ring-opening addition reaction of cyclopropenones with alkyl bromides has been successfully established.This reaction offers a concise and practical approach for the assembly ofα,β-disubstituted ... A PPh_(3)-catalyzed ring-opening addition reaction of cyclopropenones with alkyl bromides has been successfully established.This reaction offers a concise and practical approach for the assembly ofα,β-disubstituted acrylates with exclusive E-stereoselectivity at room temperature.Mechanistic investigations indicated that both the hydrogen atom on vinyl group and one oxygen atom on ester group ofα,β-disubstituted acrylates derive from H2O in dimethyl sulfoxide(DMSO).Furthermore,a gram-scale experiment and late-stage modification of the products were accomplished,thereby expanding the application potential of this methodology in organic synthesis. 展开更多
关键词 cyclopropenone phosphine-catalysis α β-disubstituted acrylates ring-opening addition reaction
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Post-synthetic modification strategy to construct Co-MOF composites for boosting oxygen evolution reaction activity
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作者 ZHENG Haifeng GUO Xingzhe +5 位作者 WEI Yunwei WANG Xinfang QI Huimin YAN Yuting ZHANG Jie LI Bingwen 《无机化学学报》 北大核心 2026年第1期193-202,共10页
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul... The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276. 展开更多
关键词 PYRENE metal-organic frameworks composite catalyst oxygen evolution reaction density functional theory
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Visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers
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作者 Feng Zhao Hongyu Ding +4 位作者 Ting Sun Chao Shen Zu-Li Wang Wei Wei Dong Yi 《Chinese Chemical Letters》 2026年第2期206-217,共12页
Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable ... Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable strategy for constructing new carbon-oxygen bonds.In comparison with traditional thermal or metal-mediated carbene transfer reactions,visible-light-promoted multi-component reaction strategy provides a mild and eco-friendly approach to access densely functionalized molecules.Recently,visible-light-induced multi-component carbene transfer reactions of diazo compounds have been rapidly developed and attracted a great deal of research interest of chemists owing to their advantages of simple operation,mild condition,high atom economy and rich structural diversity.This paper summarizes the recent research progress on the visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers with various nucleophiles.The reaction patterns of different nucleophiles and their corresponding mechanism are described in this review.The future research direction and challenges in this area are also discussed. 展开更多
关键词 VISIBLE-LIGHT Multi-component reaction Carbene insertion Diazo compounds Ring-opening reaction
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Cul-Catalyzed C—C Bond Coupling Reaction for the Construction of 2-Carbonyl-1,4-diketones
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作者 Liu Yingjie Min Laisheng +3 位作者 Yang Ruirong Song Dongxue Peng Rui Liang Deqiang 《有机化学》 北大核心 2026年第2期603-611,共9页
Transition metal-catalyzed C—C coupling reactions are a core strategy for the construction of carbon-carbon bonds in organic synthesis.Their development has not only promoted the synthesis of drugs,materials,and natu... Transition metal-catalyzed C—C coupling reactions are a core strategy for the construction of carbon-carbon bonds in organic synthesis.Their development has not only promoted the synthesis of drugs,materials,and natural products,but also promoted the development of new synthetic methods,and has also made breakthroughs in mechanism innovation and catalyst design.On this basis,a copper-catalyzed radical reaction between ketones is reported,enabling the synthesis of 2-carbonyl-1,4-diones.The method exhibits excellent applicability to multiple structural types of ketones,including aliphatic ketones with diverse substituents,aromatic ketones,and various simple ketones not limited to acetone,with wide applications,easy implementation,low catalyst toxicity,and low cost,cost-effective,and the product is easy to separate and purify. 展开更多
关键词 transition metal catalysis C—C coupling radical reaction 2-carbonyl-1 4-dione
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Progress in MOF-based catalyst design and reaction mechanisms for CO_(2)hydrogenation to methanol
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作者 YU Zhifu JIANG Lei WU Mingbo 《燃料化学学报(中英文)》 北大核心 2026年第1期146-162,共17页
Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon... Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies. 展开更多
关键词 CO_(2)hydrogenation metal-organic frameworks(MOFs) catalyst design reaction mechanism METHANOL
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Co-based Bifunctional Electrocatalyst with Sturdy Three-Dimensional Frame Construction for Oxygen Reduction and Oxygen Evolution Reactions
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作者 ZHENG Chenxi CHEN Cheng +1 位作者 LIAO Jun ZHANG Haining 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期346-352,共7页
Silica nanoparticles-stabilized cobalt and nitrogen-doped carbon materials were synthesized through pyrolysis of metal-organic-framework of ZIF-67 supported by silica nanoparticles.The experimental results reveal that... Silica nanoparticles-stabilized cobalt and nitrogen-doped carbon materials were synthesized through pyrolysis of metal-organic-framework of ZIF-67 supported by silica nanoparticles.The experimental results reveal that the introduction of the silica nanoparticles can stabilize the microstructure of the derived CoN-C materials,which in turn exhibits the promising electrocatalytic activity towards both oxygen reduction and oxygen evolution reactions.The optimized sample exhibits a better oxygen reduction activity than commercial Pt/C catalyst as confirmed by the positive shift of half-wave potential by 20 mV while it has a low overpotential of 273 mV for oxygen evolution reactions with the retained performance over 80%after 25,000 s of continuous operation.It is demonstrated that the introduction of support frame might be an effective way to improve the activity and stability of metal-organic-framework derived electrocatalyst with stabilized microstructure. 展开更多
关键词 ELECTROCATALYST metal organic framework heteroatom doping oxygen reduction reaction oxygen evolution reaction
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Advances of the bifunctional electrocatalyst toward oxygen reduction/evolution reaction
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作者 Yongxia Wang Shuang Li +7 位作者 Mengli Li Xi Luo Yang Zhang Xiangzhi Cui Guicheng Liu Woochul Yang Haitao Huang Jinli Qiao 《Journal of Energy Chemistry》 2026年第3期574-607,共34页
The development of economical,highly efficient,and stable bifunctional electrocatalysts for both the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR)remains a critical focus in advancing rechargeab... The development of economical,highly efficient,and stable bifunctional electrocatalysts for both the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR)remains a critical focus in advancing rechargeable metal-air battery systems.Significant progress has been made in the design of high-performance bifunctional electrocatalysts,the development of novel oxygen electrode architectures,and the in-depth understanding of electrocatalytic mechanisms through combined experimental and computational studies.This work provides a comprehensive review of recent advancements in design strategies for oxygen catalysts,including homogeneous electrodes,asymmetric electrodes,and biomimetic electrodes,are thoroughly discussed and summarized.Then,the advanced catalyst modification strategies for ORR/OER are summarized,focusing on critical factors such as enhancement effect of metal/nonmental and synergistic enhancement effect in multiple catalyst.Subsequently,a representative performance evaluation is presented,based on the reported oxygen electrodes used in rechargeable metal-air battery applications.By focusing on these key areas,the review outlines the current challenges and future prospects for the development of bifunctional oxygen electrocatalysts,aiming to guide the design of high-performance bifunctional electrocatalysts and to elucidate the underlying mechanisms involved. 展开更多
关键词 Oxygen reduction reaction Oxygen evolution reaction Design strategy MODIFICATION Rechargeable metal-air battery
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Production of ^(287,288)Mc isotopes in the ^(48)Ca+^(243)Am reaction at China Accelerator Facility for Superheavy Elements
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作者 X.Y.Huang Z.Y.Zhang +38 位作者 J.G.Wang L.Ma C.L.Yang M.H.Huang X.L.Wu Z.G.Gan H.B.Yang M.M.Zhang Y.L.Tian Y.S.Wang J.Y.Wang Y.H.Qiang G.Xie S.Y.Xu Z.Zhao Z.C.Li L.C.Sun L.Zhu X.Zhang H.Zhou F.Guan Z.H.Li W.X.Huang Z.Qin Y.Wang X.J.Yin Y.F.Cui Z.W.Lu Y.He L.T.Sun Z.Z.Ren S.G.Zhou V.K.Utyonkov A.A.Voinov Yu.S.Tsyganov A.N.Polyakov D.I.Solovyev N.D.Kovrizhnykh M.V.Shumeiko 《Chinese Physics Letters》 2026年第1期9-16,共8页
We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-... We report the results of the experiment on synthesizing ^(287,288)Mc isotopes (Z=115) using the fusionevaporation reaction ^(243)Am(^(48)Ca,4n,3n)^(287,288)Mc at the Spectrometer for Heavy Atoms and Nuclear Structure-2(SHANS2),a gas-filled recoil separator located at the China Accelerator Facility for Superheavy Elements(CAFE2).In total,20 decay chains are attributed to ^(288)Mc and 1 decay chain is assigned to ^(287)Mc.The measured oa-decay properties of ^(287,288)Mc as well as its descendants are consistent with the known data.No additional decay chains originating from the 2n or 5n reaction channels were detected.The excitation function of the ^(243)Am(^(48)Ca,3n)^(288)Mc reaction was measured at the cross-section level of picobarn,which indicates the promising capability for the study of heavy and superheavy nuclei at the facility. 展开更多
关键词 spectrometer heavy atoms fusionevaporation reaction China Accelerator Facility Superheavy Elements PRODUCTION decay chains ISOTOPES ca am reaction mc
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Advanced isoconversional kinetic analysis of lepidolite sulfation product decomposition reactions for selectively extracting lithium
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作者 Yubo Liu Baozhong Ma +4 位作者 Jiahui Cheng Xiang Li Hui Yang Chengyan Wang Yongqiang Chen 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期217-227,共11页
The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.A... The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.Accordingly,comprehensive kinetic study by employing thermalgravimetric analysis at various heating rates was presented in this paper.Two main weight loss regions were observed during heating.The initial region corresponded to the dehydration of crystal water,whereas the subsequent region with overlapping peaks involved complex decomposition reactions.The overlapping peaks were separated into two individual reaction peaks and the activation energy of each peak was calculated using isoconversional kinetics methods.The activation energy of peak 1 exhibited a continual increase as the reaction conversion progressed,while that of peak 2 steadily decreased.The optimal kinetic models,identified as belonging to the random nucleation and subsequent growth category,provided valuable insights into the mechanism of the decomposition reactions.Furthermore,the adjustment factor was introduced to reconstruct the kinetic mechanism models,and the reconstructed models described the kinetic mechanism model more accurately for the decomposition reactions.This study enhanced the understanding of the thermochemical behavior and kinetic parameters of the lepidolite sulfation product decomposition reactions,further providing theoretical basis for promoting the selective extraction of lithium. 展开更多
关键词 LITHIUM LEPIDOLITE decomposition reactions KINETICS isoconversional analysis
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Growth of Ce-doped NiCo-LDHs on tin dioxide-modified nickel foam as oxygen evolution reaction catalyst electrode
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作者 Zhongjie Song Nannan Zhang +3 位作者 Jun Yu Huiyu Sun Zhengying Wu Yukou Du 《Chinese Chemical Letters》 2026年第1期689-695,共7页
Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthes... Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer. 展开更多
关键词 Oxygen evolution reaction HETEROSTRUCTURE DOPING Conductive layer
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Synergistic Oxygen Vacancy and Ru-N Coordination in RuO_(2)@NCC for Enhanced Acidic Oxygen Evolution Reaction
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作者 Mi Luo Linyao Huang +2 位作者 Chen Shen Tianhua Yang Chenguang Wang 《Carbon Energy》 2026年第1期115-125,共11页
Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a fo... Developing efficient and durable electrocatalysts for acidic oxygen evolution reaction(OER)is pivotal for advancing proton exchange membrane water electrolysis(PEMWEs),yet balancing activity and stability remains a formidable challenge.Herein,we propose a dual-engineering strategy to stabilize Ru-based catalysts by synergizing the oxygen vacancy site-synergized mechanism-lattice oxygen mechanism(OVSM-LOM)with Ru-N bond stabilization.The engineered RuO_(2)@NCC catalyst exhibits exceptional OER performance in 0.5 M H2SO4,achieving an ultralow overpotential of 215 mV at 10 mA cm^(-2) and prolonged stability for over 327 h.The catalyst delivers 300 h of continuous operation at 1 A cm^(-2),with a negligible degradation rate of only 0.067 mV h-1,further demonstrating its potential for practical application.Oxygen vacancies unlock the OVSM-LOM pathway,bypassing the sluggish adsorbate evolution mechanism(AEM)and accelerating reaction kinetics,while the Ru-N bonds suppress Ru dissolution by anchoring low-valent Ru centers.Quasi-in situ X-ray photoelectron spectroscopy(XPS),X-ray absorption spectroscopy(XAS),and isotopic labeling experiments confirm the lattice oxygen participation with *O formation as the rate-determining step.The Ru-N bonds reinforce the structural integrity by stabilizing low-valent Ru centers and inhibiting overoxidation.Theoretical calculations further verify that the synergistic interaction between OVs and Ru-O(N)active sites optimizes the Ru d-band center and stabilizes intermediates,while Ru-N coordination enhances structural integrity.This study establishes a novel paradigm for designing robust acidic OER catalysts through defect and coordination engineering,bridging the gap between activity and stability for sustainable energy technologies. 展开更多
关键词 OVSM-LOM oxygen evolution reaction oxygen vacancy Ru-N XAFS
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Solar-Driven Redox Reactions with Metal Halide Perovskites Heterogeneous Structures
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作者 Qing Guo Jin‑Dan Zhang +1 位作者 Jian Li Xiyuan Feng 《Nano-Micro Letters》 2026年第2期337-367,共31页
Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks... Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks such as inferior stability,severe charge-carrier recombination,and limited active sites.Heterojunctions have recently been widely constructed to improve light absorption,passivate surface for enhanced stability,and promote charge-carrier dynamics of MHPs.However,little attention has been paid to the review of MHPs-based heterojunctions for photocatalytic redox reactions.Here,recent advances of MHPs-based heterojunctions for photocatalytic redox reactions are highlighted.The structure,synthesis,and photophysical properties of MHPs-based heterojunctions are first introduced,including basic principles,categories(such as Schottky junction,type-I,type-II,Z-scheme,and S-scheme junction),and synthesis strategies.MHPs-based heterojunctions for photocatalytic redox reactions are then reviewed in four categories:H2evolution,CO_(2)reduction,pollutant degradation,and organic synthesis.The challenges and prospects in solar-light-driven redox reactions with MHPs-based heterojunctions in the future are finally discussed. 展开更多
关键词 Metal halide perovskite HETEROJUNCTION Redox reaction Solar-to-chemical conversion
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