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Tailoring BaCe0.7Zr0.1(Dy0.1|Yb0.1)0.2O3-δ electrolyte through strategic Cu doping for low temperature proton conducting fuel cells:Envisioned theoretically and experimentally

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Journal of Energy Chemistry 2025年第2期101卷 692-701页

作者： Zaheer Ud Din Babar Muhammad Bilal Hanif Yan'an Li Wan-Ting Wang Hanchen Tian Cheng-Xin Li State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and Engineering Xi'an Jiaotong University Department of Inorganic Chemistry Faculty of Natural Sciences Comenius University Bratislava

This study addresses the challenge of high sintering temperatures in proton-conducting fuel cells（PCFCs）with BaCeO3-doped *** demonstrate that 1 mol% copper（Cu） doping at the B-site of BaCe0.7Zr0.1(Dy0.1|Yb0.1)0.2O3-δ（BCZDYb） improves sintering behavior,enabling densification at1400℃.However,Cu doping disrupts stoichiometry,creating barium vacancies and reducing protonaccepting cations,affecting overall *** mechanism is confirmed through density functional theory（DFT） calculations and various experimental techniques,including crystal structure analysis using X-ray diffraction（XRD） and morphology and elemental analysis via field emission scanning electron microscopy（FESEM） and energy-dispersive X-ray spectroscopy（EDS）.Electrochemical measurements are performed using the electrochemical impedance spectroscopy（EIS）.The ionic conductivity of1 mol% Cu-doped BCZDYb（BCZDYb-1） is 1.49×10-2S cm-1at 650℃,which is～3.58 times higher than that of BCZDYb sintered at 1200℃.The BCZDYb-1 exhibits ～16 times higher grain boundary conductivity when sintered at 1400℃,compared to undoped *** single cell employing BCZDYb-1 as the electrolyte achieved a power density of ～606 mW cm-2at 550℃.These results indicate that a controlled amount of Cu doping can enhance densification while maintaining high ionic co nductivity,making it suitable for practical applications in PCFCs operating at lower temperatures.

关键词： BaCe0.7Zr0.1(Dy0.1|Yb0.1)0.2O3−δ (BCZDYb) Cu-doping Densification Electrical conductivity Proton conducting fuel cells (PCFCs) Sintering

Cooperative output regulation of heterogeneous directed multi-agent systems:a fully distributed model-free reinforcement learning framework

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Science China(Information Sciences) 2025年第2期68卷 170-185页

作者： Xiongtao SHI Yanjie LI Chenglong DU Huiping LI Chaoyang CHEN Weihua GUI Guangdong Key Laboratory of Intelligent Morphing Mechanisms and Adaptive Robotics School of Mechanical Engineering and AutomationHarbin Institute of Technology (Shenzhen) School of Automation Central South University School of marine Science and Technology Northwestern Polytechnical University School of Information and Electrical engineering Hunan University of Science and Technology

In this paper, the cooperative output regulation(COR) problem of a class of unknown heterogeneous multi-agent systems(MASs) with directed graphs is studied via a model-free reinforcement learning(RL) based fully distributed eventtriggered control(ETC) strategy. First, we consider the scenario that the exosystem is accessible globally to all agents, an internal model-based augmented algebraic Riccati equation(AARE) is constructed, and its solution is learned by the proposed model-free RL algorithm via online input-output data. Further, for the scenario that the exosystem is accessible only to its adjacent followers, the distributed observers are designed for each agent to get the state of the exosystem, and an internal modelbased fully distributed adaptive ETC protocol is then synthesized to construct the corresponding AARE, and the feedback gain matrix is learned in a model-free fashion. The model-free RL-based control protocol proposed in this paper can not only remove the prior knowledge of agents' dynamics, but also release the dependence on global information by the adaptive event-triggered mechanism(ETM) and the new graph-based Lyapunov function. Finally, simulation results are illustrated to show the feasibility and effectiveness of the proposed control scheme.

关键词： model-free reinforcement learning unknown heterogeneous multi-agent systems fully distributed event-triggered control directed graph

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High-thermal free vibration analysis of functionally graded microplates using a new finite element formulation based on TSDT and MSCT

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Defence Technology(防务技术) 2025年第2期44卷 131-149页

作者： Huu Trong Dang Nhan Thinh Hoang Quoc Hoa Pham Trung Thanh Tran Huy Gia Luong faculty of Mechanical engineering Technology Vinh Long University of Technology EducationVinh Long 91000Viet Nam Institute for Creative Design and Business Nguyen Tat Thanh UniversityHo Chi Minh City 70000Viet Nam faculty of engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City 70000Viet Nam faculty of Mechanical engineering Le Quy Don Technical UniversityHanoi 10000Viet Nam TechnoStar Vietnam TechnoStar Co.LtdHo Chi Minh City 70000Viet Nam

Recent advancements in additive manufacturing(AM)have revolutionized the design and production of complex engineering *** these advancements,their mathematical modeling and computational analysis remain significant *** research aims to develop an effective computational method for analyzing the free vibration of functionally graded(FG)microplates under high temperatures while resting on a Pasternak foundation(PF).This formulation leverages a new thirdorder shear deformation theory(new TSDT)for improved accuracy without requiring shear correction ***,the modified couple stress theory(MCST)is incorporated to account for sizedependent effects in *** PF is characterized by two parameters including spring stiffness(k_(w))and shear layer stiffness(k_(s)).To validate the proposed method,the results obtained are compared with those of the existing ***,numerical examples explore the influence of various factors on the high-temperature free vibration of FG *** factors include the length scale parameter(l),geometric dimensions,material properties,and the presence of the elastic *** findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal *** addition,the findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal *** addition,the results of this research will have great potential in military and defense applications such as components of submarines,fighter aircraft,and missiles.

关键词： Microplates Functionally graded material Finite element method Modified couple stress theory New TSDT High-thermal free vibration Pasternak foundation

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Flotation separation of chalcopyrite from pyrite using mineral fulvic acid as selective depressant under weakly alkaline conditions

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Transactions of Nonferrous Metals Society of China 2025年第1期35卷 313-325页

作者： Zhi-hao SHEN Shu-ming WEN Jia-mei HAO Qi-cheng FENG State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a *** experiments showed that MFA produced a stronger inhibition effect on pyrite than on *** separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately *** copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,*** adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the *** force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.

关键词： mineral fulvic acid chalcopyrite pyrite flotation separation

Fabrication and application of SiNWs based PANI:MOx heterostructures for human respiratory monitoring

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Journal of Semiconductors 2025年第03期 56-69页

作者： Muhammad Taha Sultan Anca Dumitru Elham Fakhri Rachel Brophy Snorri Thorgeir Ingvarsson Andrei Manolescu Halldor Gudfinur Svavarsson Reykjavik University Department of Engineering University of Iceland University of Bucharest Faculty of Physics

In this study, we investigate an innovative hybrid structure of silicon nanowires（SiNWs） coated with polyaniline（PANI）:metal oxide（MOx） nanoparticles, i.e., WO3and TiO2, for respiratory sensing. To date, few attempts have been made to utilize such hybrid structures for that application. The Si NWs were fabricated using metal-assisted chemical etching（MACE）,whereas PANI:MOxwas deposited using chemical oxidative polymerization. The structures were characterized using Raman spectroscopy, X-ray diffraction, and scanning electron microscopy. The sensing characteristics revealed that the hybrid sensor exhibited a considerably better response than pure Si NWs:MOxand Si NWs:PANI. Such an enhancement in sensitivity is attributed to the formation of a p-n heterojunction between PANI and MOx, the wider conduction channel provided by PANI, increased porosity in SiNWs/PANI:WO3hybrid structures, which creates active sites, increased oxygen vacancies, and the large surface area compared to that available in pure MOxnanoparticles. Furthermore, less baseline drift and increased sensor stability were established for the SiNWs structure coated with PANI:WO3, as compared to PANI:TiO2.

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A Simulation Study to Assess Impacts of Habitat-Dependent Parameters of Surplus Production Model on Stock Assessment of Chilean Jack Mackerel in the Southeast Pacific Ocean

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Journal of Ocean University of China 2025年第1期24卷 169-181页

作者： LI Gang CAO Yangming CAO Jie CHEN Xinjun ZOU Xiaorong College of marine Science Shanghai Ocean UniversityShanghai 201306China National engineering Research Center for Oceanic Fisheries Shanghai 201306China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai 201306China Department of Applied Ecology Center for Marine Sciences and TechnologyNorth Carolina State UniversityMorehead CityNC 28557USA

Pelagic fish are the most abundant species in upwelling regions,contributing 25%of total global fisheries ***-driven changes in the marine environment play a crucial role in their population *** Chilean jack mackerel(Trachurus murphyi)as an example,this study conducted simulations to quantify the impacts of environmental variations on the stock assessment.A habitat-based surplus production model was developed by integrating suitable habitat area into the model parameters carrying capacity(K)and intrinsic growth rate(r),with a suitable habitat area serving as the proxy for the environmental conditions for Chilean jack mackerel in the Southeast Pacific *** dynamics of Chilean jack mackerel stock and fisheries data were simulated,and four assessment models with different configurations were built to fit simulated data,with or without considering environmental *** results indicated that Joint K-r model,which integrated both parameters with the suitable habitat area index,outperformed the others by coming closest to the‘true'population *** habitat variations in the estimation model tended to overestimate biomass and underestimate harvest rate and reference *** observation and process error,the results were estimated with bias,while FMSY is relatively *** research illustrates the importance to consider random errors and environmental influences on populations,and provides foundation guidelines for future stock assessment.

关键词： Trachurus murphyi simulations suitable habitat area stock assessment errors Southeast Pacific Ocean

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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 SourcesWuhan UniversityWuhan 430072HubeiChina State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyiChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of BelarusMinsk 220072Belarus State Key Laboratory of marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and TechnologySchool of Marine Science and EngineeringHainan UniversityHaikou 570228HainanChina Department of Chemical and Environmental engineering University of Nottingham Ningbo ChinaNingbo 315100ZhejiangChina

Methane, an abundant one-carbon(C_(1)) 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 CO_(2)emissions 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 CO_(2)emission.

关键词： Methane Electrochemical conversion Reaction mechanism Catalyst design Electrode Electrocatalysis

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The formation,development and classification of rail corrugation:a survey on Chinese metro

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Railway engineering Science 2025年第1期33卷 43-61页

作者： Yang Wang Hong Xiao Zhihai Zhang Xuhao Cui Yihao Chi Mahantesh M.Nadakatti School of Civil engineering Beijing Jiaotong UniversityBeijing 100044China Beijing Key Laboratory of Track engineering Beijing Jiaotong UniversityBeijing 100044China faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China Department of Mechanical engineering KLS Gogte Institute of TechnologyBelagavi 590008India

Investigations into rail corrugation within metro systems have traditionally focused on specific mechanisms,thereby limiting the generalizability of proposed *** the commonalities in rail corrugation across diverse metro lines remains pivotal for elucidating its underlying *** present study conducted extensive field surveys and tracking tests across 14 Chinese metro *** employing t-distributed stochastic neighbor embedding(t-SNE)for dimensional reduction and employing the unsupervised clustering algorithm DBSCAN,the research redefines the classification of metro rail corrugation based on characteristic *** analysis encompassed spatial distribution and temporal evolution of this *** revealed that floating slab tracks exhibited the highest proportion of rail corrugation at 47%.Notably,ordinary monolithic bed tracks employing damping fasteners were more prone to inducing rail *** primarily manifested in curve sections with radii between 300 and 500 m,featuring ordinary monolithic bed track and steel-spring floating slab track structures,with wavelengths typically between 30 and 120 ***–slip vibrations of the wheel–rail system maybe led to short-wavelength corrugations(40–60 mm),while longer wavelengths(200–300 mm)exhibited distinct fatigue damage characteristics,mainly observed in steel-spring floating slab tracks and small-radius curve sections of ordinary monolithic bed tracks and ladder sleeper tracks.A classification system comprising 57 correlated features categorized metro rail corrugation into four distinct *** research outcomes serve as critical benchmarks for validating various theories pertaining to rail corrugation formation.

关键词： Metro Rail corrugation Formation mechanism Development law Field test

Hybrid and enhanced electrokinetic system for soil remediation from heavy metals and organic matter

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Journal of Environmental Sciences 2025年第1期147卷 424-450页

作者： Faris M.Hamdi Namuun Ganbat Ali Altaee Akshaya K.Samal Ibrar Ibrar John L.Zhou Adel O.Sharif Centre for Green Technology School of Civil and Environmental EngineeringThe University of Technology Sydney15 BroadwayNSW 2007Australia Department of Civil engineering Jazan UniversityJazan 82822Saudi Arabia Centre for Nano and Material Sciences Jain UniversityRamanagaraBangaloreKarnataka 562112India School of Mechanical Sciences Faculty of Engineering and Physical SciencesUniversity of SurreyAustralia

The electrokinetic(EK)process has been proposed for soil decontamination from heavy metals and organic *** advantages of the EK process include the low operating energy,suitability for fine-grained soil decontamination,and no need for *** the last three decades,enhanced and hybrid EK systems were developed and tested for improving the efficiency of contaminants removal from *** enhanced-EK processes exhibited excellent efficiency in removing contaminants by controlling the soil pH or the chemical reaction of *** hybrid systems were tested to overcome environmental hurdles or technical drawbacks of decontamination *** of the EK process with phytoremediation,bioremediation,or reactive filtermedia(RFM)improved the remediation process performance by capturing contaminants or facilitating biological agents’movement in the ***,EK process coupling with solar energy was proposed to treat off-grid contaminated soils or reduce the EK energy *** study reviews recent advancements in the enhancement and hybrid EK systems for soil remediation and the type of contaminants targeted by the *** study also covered the impact of operating parameters,imperfect pollution separation,and differences in the physicochemical characteristics and microstructure of soil/sediment on the EK ***,a comparison between various remediation processes was presented to highlight the pros and cons of these technologies.

关键词： Electrokinetic Soil remediation Reactive filter media Enhanced electrokinetic Contaminants