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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： Peng zheng Wang zhou Ying Mo Biao zheng Miaomiao Han Qin zhong Wenwen Yang Peng Gao Lezhi Yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University Changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and x-ray photoelectron spectroscopy （xPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： x ray photoelectron spectroscopy

Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： zheng Weilin WANG Qijiao xIAO Huahua CHEN xiaoxiao xIE Fan zENG Wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace University State Key Laboratory of Fire Science University of science and Technology of China AVIC Shenyang Aircraft Design and Research Institute

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature（T=300-400 K）,initial pressure（P=0.1-0.3 MPa）,turbulence intensity（u'=1.0-2.7 m/s）,oxygen volumetric percentage(φ（O2）=15%-21%) and carbon dioxide volumetric percentage(φ（CO2）=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale（D6-D8） disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： fan-stirred turbulent combustor geometry characteristics large-scale wrinkling network topology wavelet decomposition

Experimental Study on Diesel Spray and Flame Asymmetry Characteristics of Dual-Orifice Nozzles for a Medium-Speed Engine

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Journal of Thermal Science 2025年第1期34卷 303-322页

作者： JU Dehao LIU Rui zheng Liang DENG Jiahui zHANG Wenzheng HUO Jinlu HUANG Li Shanghai Marine Diesel Engine Research Institute National Key Laboratory of Marine Engine Science and Technology Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong University

The asymmetry of the multi-orifice spray will cause uneven heat load of the marine diesel engine,thereby affecting its working performance and service ***,an in-depth understanding of the spray and flame characteristics of multi-orifice nozzles will guide the optimization of the nozzle structure,needle design and diesel atomization and combustion *** this reason,four groups of dual-orifice nozzles with different hole diameters(0.1-0.55 mm) and mass flow rates covering the typical marine medium-speed diesel injections are designed and customized,and the constant volume chamber(CVC) with high temperature and pressure is used to simulate the actual in-cylinder working conditions of the diesel engine for the spray visualization *** study the asymmetry of the fuel sprays discharged from a diesel injector,the multi-orifice nozzle is simplified as a dual-orifice nozzle in this *** with x-ray Computed Tomography(CT) imaging technology,the influences of the nozzle internal structure on the spray and flame asymmetry are studied in the constructed supercritical *** is found that the asymmetry of the inlet angle and the equivalent length-diameter ratio is positively correlated with the inconsistency of the dual *** an increase in the injection pressure and nozzle diameter,the asymmetry of the dual spray becomes more pronounced,resulting in greater disparities in the ignition delay times and ignition positions of the two ***,the increase in nozzle diameter also leads to combustion instability,resulting in a flame with a serrated *** the increase of ambient temperature,the proportion of liquid phase in the jet decreases and the relative density of spray front decreases.

关键词： atomization dual-orifice nozzle nozzle structure spray flame asymmetry

Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 58-69页

作者： Jie Wang Wei Wang xuheng Chen Junfang Bao Qiuyue Hao Heng zheng Runsheng xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

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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

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdznSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai xiaodong Li Peng Ai Wanrong Guo Tuo zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdznSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the zn atom, culminate in the profound anharmonicity in the layered NdznSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdznSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdznSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(zT) of 3.40 at 900 K is achieved for the n-type NdznSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdznSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

Personalized federated few-shot node classification

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Science China(Information Sciences) 2025年第1期68卷 204-218页

作者： Yunfeng zHAO xintong HE Guoxian YU Jun WANG Yongqing zheng Carlotta DOMENICONI School of Software Shandong University Joint SDU-NTU Centre for Artificial Intelligence Research Shandong University Department of Mathematics National University of Singapore Department of Computer Science George Mason University

Personalized federated learning(PFL) aims to train customized models for individual clients in a decentralized setting, with the account of non-independent and identically distributed data across clients. However, most PFL methods adopt uniform classification layers for diverse clients and give rise to error-prone predictions, due to the task heterogeneity notably prominent in decentralized graph data scenarios. Although some PFL solutions setup client-specific classification layers for each client and optimize them only locally, they are corrupted with limited local training data. We propose an innovative solution called federated parameter decoupling and node augmentation(Fed PANo) to address these problems and to achieve personalized federated few-shot node classification, which is a prevalent and challenging but unexplored topic. Specifically, Fed PANo first separates the local model into the GNN and classifier to handle unique client-specific task variations. The GNN is trained through federated learning to capture shared knowledge of graph nodes across clients, while the classifier is custom-designed and trained individually for each client. Additionally, a generic classifier shared among clients is adopted to encourage the GNN's grasp of shared information. Then Fed PANo further proposes the node generator along with its local and collaborative training strategies to deal with the node scarcity of clients. Extensive experimental results on benchmark datasets confirm that Fed PANo outperforms eight competitive baselines across different settings.

关键词： personalized federated learning few-shot learning node classification task heterogeneity parameter decoupling node augmentation

Influence of introducing zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu zhenyu Sun Weichen zheng Liangwei zhang Yanling xue Wenning Liu Shoumei xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

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Cholesterol metabolism: physiological versus pathological aspects in intracerebral hemorrhage

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Neural Regeneration Research 2025年第4期20卷 1015-1030页

作者： Ruoyu Huang Qiuyu Pang Lexin zheng Jiaxi Lin Hanxi Li Lingbo Wan Tao Wang Department of Forensic Science School of Basic Medicine and Biological SciencesSuzhou Medicine College of Soochow UniversitySuzhouJiangsu ProvinceChina

Cholesterol is an important component of plasma membranes and participates in many basic life functions,such as the maintenance of cell membrane stability,the synthesis of steroid hormones,and *** plays a key role in the establishment and maintenance of the central nervous *** brain contains 20%of the whole body’s cholesterol,80%of which is located within myelin.A huge number of processes(e.g.,the sterol regulatory element-binding protein pathway and liver x receptor pathway)participate in the regulation of cholesterol metabolism in the brain via mechanisms that include cholesterol biosynthesis,intracellular transport,and *** brain injuries or diseases involving crosstalk among the processes above can affect normal cholesterol metabolism to induce detrimental ***,we hypothesized that cholesterol-related molecules and pathways can serve as therapeutic targets for central nervous system *** hemorrhage is the most severe hemorrhagic stroke subtype,with high mortality and *** cholesterol levels are associated with the risk of intracerebral ***,secondary pathological changes after intracerebral hemorrhage are associated with cholesterol metabolism dysregulation,such as neuroinflammation,demyelination,and multiple types of programmed cell *** cholesterol accumulation in the brain has been found after intracerebral *** this paper,we review normal cholesterol metabolism in the central nervous system,the mechanisms known to participate in the disturbance of cholesterol metabolism after intracerebral hemorrhage,and the links between cholesterol metabolism and cell *** also review several possible and constructive therapeutic targets identified based on cholesterol metabolism to provide cholesterol-based perspectives and a reference for those interested in the treatment of intracerebral hemorrhage.

关键词： cell death cholesterol metabolism intracerebral hemorrhage myelination therapeutic target

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