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Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang Chen Yongyue Zhuang Yanxin Qiao Yu Zhang Aihua Yuan hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

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Experimental Study for Effect of Multi-Site Spark Ignition on Dedicated Hybrid Engine Performance under High Dilution Condition

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Journal of Thermal Science 2025年第1期34卷 254-267页

作者： YAN Bowen WATERS Benjamin HAINES Andrew MCGHEE Mike hu Tiegang DENG Wei PU Yongxian MA Tianyu Powertrain Engineering R&D Center Chongqing Changan Automobile Co.Ltd. Changan UK R&D Centre Limited

In this study,a triple spark ignition scheme was first designed on a three-cylinder 1.5-L dedicated hybrid engine（DHE）.On this basis,the effect of different ignition modes on engine combustion and emission characteristics was studied,especially under high dilution *** results tested at 2000 r/min and 0.8 MPa BMEP（brake mean effective pressure） show that with highly increased in-cylinder flow intensity,using only passive prechamber（PPC） has a lower lean limit than that with single central spark plug（CSP）,thereby leading to slightly higher minimum fuel consumption and nitrogen oxides（NOx） *** side spark plugs（SSP）based on PPC can result in improved capability of lean limit extension and engine performance than ***,the improvement level is lower than that with triple spark plugs（TSP）.As the excess air ratio λincreases,the advantage of PPC and PPC with SSP in improving the combustion phasing compared with CSP gradually ***,the increasing tendency of their ignition delay and combustion duration is more *** added SSP based on PPC can effectively shorten the ignition delay of leaner mixture,but the combustion duration can be only slightly *** a result,under extremely lean condition,the advantage of PPC and PPC with SSP in terms of combustion characteristics over CSP becomes much *** contrast,the TSP ignition can achieve much shorter ignition delay and combustion duration simultaneously under this *** to the highest available dilution level,the TSP ignition achieves the lowest raw ***,it can also reduce the raw carbon monoxide（CO） and hydrocarbons（HC） emissions compared to CSP due to a more thorough combustion of the end gas *** on the excellent performance of TSP,the highest engine brake thermal efficiency（BTE） was further *** results show that with normal RON 92 fuel,the engine finally achieved 43.69% and 45.02% BTE under stochiometric mode with exhaust

关键词： dedicated hybrid engine high dilution condition NOx emissions passive prechamber thermal efficiency triple spark plug scheme

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu Jiang Ma Lina hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： Jing Lei huijie Zhang Jian Yang Jia Ran Jiqiang Ning Haiyan Wang Yong hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of Chemistry Zhejiang Normal University Jinhua Advanced Research Institute Department of Optical Science and Engineering Fudan University College of Chemistry and Materials Engineering Zhejiang A&F University

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF) has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA), but there still remain problems such as limited yield, short cycle life,and ambiguous reaction mechanism. Despite many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF, a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still lacking. We herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA, particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts, including heterointerface construction, defect engineering,single-atom engineering, and in situ reconstruction. Experimental characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated, and challenges and future directions of electrochemical oxidation of HMF are also prospected. This review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Structural design

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng Song Ihar Razanau Juanxiu Xiao Wei Xiao Di hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

A Novel Model for Describing Rail Weld Irregularities and Predicting Wheel-Rail Forces Using a Machine Learning Approach

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 555-577页

作者： Linlin Sun Zihui Wang Shukun Cui Ziquan Yan Weiping hu Qingchun Meng State Key Laboratory of High-Speed Railway Track System China Academy of Railway Sciences Corporation LimitedBeijing100081China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed *** can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and *** researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry ***,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric *** this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to *** vertical dynamic forces in the time and frequency domains were compared under different running *** forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed ***,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is *** results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the *** ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.

关键词： Rail weld irregularity high-speed railway vehicle-track coupled dynamics wheel/rail dynamic vertical force artificial neural networks

Paleoclimate data assimilation: Principles and prospects

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Science China Earth Sciences 2025年

作者： Haoxun ZHANG Mingsong LI Yongyun hu Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of PhysicsPeking University Institute of Ocean Research Peking University

Reconstructing climate states during geological periods is a key focus in studying Earth system evolution. Substantial progress has been achieved in reconstructing paleoclimate and paleoenvironment using both Earth system models and paleoclimate proxies. However, current paleoclimate reconstructions face several challenges:the accuracy of Earth system model simulations relies on model parameter settings. Paleoclimate proxy data exhibit significant variability across different periods and regions, and proxy data are often sparse, hindering the accuracy and global relevance of proxy-based *** the pros and cons of these methods, paleoclimate data assimilation can effectively integrate Earth system models and paleoclimate proxy data, enhancing the precision and global relevance of reconstructions. Using approaches such as the ensemble Kalman filter as an example, this paper introduces the principles of paleoclimate data assimilation and reviews recent advancements in reconstructing paleoclimate states using these techniques. Paleoclimate data assimilation offers new insights and advanced techniques for paleoclimate reconstruction, with potential applications extending to the entire Cenozoic, Mesozoic, and even Paleozoic eras. These applications could deepen our understanding of the past climatic backgrounds of extreme climate events such as glacial-interglacial cycles, hyperthermals, and oceanic anoxic events, providing a reference for predicting future climate change.

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基于内分泌科医师问卷调查结果评价武汉市胰岛素类药品集中采购分组办法的合理性及可行性

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中国药房 2022年第6期33卷 666-672页

作者：胡惠子文小桐杨莹毛李宁王兆仑罗佳张维纯毛宗福崔丹湖北中医药大学管理学院武汉430065 武汉大学全球健康研究中心武汉430071 武汉大学健康学院武汉430071

目的调查内分泌科医师对胰岛素类药品临床转换替代的态度,为完善胰岛素集中带量采购方案提供依据。方法采用问卷调查法,以南昌市三级甲等综合医院的内分泌科医师为调查对象,从代际层面、议价组层面、通用名层面和厂牌/规格层面4个维度... 详细信息

目的调查内分泌科医师对胰岛素类药品临床转换替代的态度,为完善胰岛素集中带量采购方案提供依据。方法采用问卷调查法,以南昌市三级甲等综合医院的内分泌科医师为调查对象,从代际层面、议价组层面、通用名层面和厂牌/规格层面4个维度调查内分泌医师认可的胰岛素可转换替代比例。结果共成功发放问卷89份,占南昌市三级甲等综合医院在岗内分泌科医师(共111名)的80.2%;回收89份问卷,其中1份为无效问卷,有效率为98.9%。调查结果显示,在代际层面,93.2%的内分泌科医师会首选胰岛素类似物。在议价组层面,医师认可的组三与组四药品间相互转换替代比例的加权平均数为63.9%。在通用名、厂牌/规格层面,医师认可的各组药品间相互转换替代比例的加权平均数均在70%以上。结论武汉市胰岛素分组办法较为合理,能实现组内胰岛素安全临床转换替代,建议取消长效人胰岛素竞价组;组内药品间可转换替代比例的加权平均数均较高,建议提高胰岛素约定采购量,并进行“量价挂钩”谈判;受访医师选用胰岛素起始治疗方案时更注重疗效、安全等因素,故胰岛素的替换要以临床疗效、用药安全为前提。

关键词：胰岛素临床转换替代武汉南昌药品集中采购内分泌科医师分组办法问卷调查

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Multicomponent polymerization of elemental sulfur,difluoromethylene phosphobetaine and aryl silyl ethers toward aromatic poly(O,O′-monothiocarbonate)s

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Science China Chemistry 2025年

作者： Yongjiang Yu Rongrong hu Ben Zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of Technology School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong Kong AIE Institute

Polythiocarbonates with similar structures to polycarbonates, have emerged as a group of promising sulfur-containing polymers with a range of practical applications, taking advantages of their excellent optical properties, good thermal stability and filmforming ability, and so on. However, the synthesis of polythiocarbonates generally suffered from mixed isomeric structures of repeating units, and hazardous sulfur-containing reagents. In this work, an efficient multicomponent reaction of elemental sulfur,difluoromethylene phosphobetaine（PDFA）, and aryl silyl ethers was designed with the assistance of organic base 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene（MTBD） to produce 12 kinds of O,O′-monothiocarbonate compounds in up to 93% yields,taking advantages of the unique chemical property of difluorocarbene, and the deprotection of silyl group by F-generated from PDFA. Most importantly, the MTBD-assisted multicomponent polymerization of bis（aryl silyl ether）s, elemental sulfur, and PDFA was developed, affording 12 kinds of poly（O,O′-monothiocarbonate）s with well-defined structures, high Mws of up to16900 g/mol and high yields（up to 99%）. These poly（O,O′-monothiocarbonate）s possessed good film-forming properties and thermal stability, high light refractive indices and transmittance. The facile synthesis of these polymonothiocarbonates might pave the way for the development of promising sulfur-containing polymer materials.

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