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Science China Chemistry 2025年

作者： haoyu zhang Yuhang Li Yu Nie Xinyu Dou Haodong Ji Xin Tan Jinhua Ye Tao Yu School of Chemical Engineering and Technology Tianjin University Eco-environment and Resource Efficiency Research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School School of Environmental Science and Engineering Tianjin University Advanced Catalytic Materials Research Center School of Materials Science and Engineering Tianjin University Research Center for Solar Driven Carbon Neutrality Hebei University

Photothermal catalytic CO2hydrogenation is an effective means of utilizing carbon ***,it is severely limited in terms of kinetics and ***,it is necessary to meticulously design catalysts to solve this ***,a sandwich structured NiO@InNi/In2O3is designed to intrinsically regulate the direction of photogenerated carriers transfer,resulting in a CO yield of 42.97 mmol g-1h-1(1290.3μmol h-1) with a selectivity near to 100%.InNi alloy favors the collection of photogenerated carriers by the parallel way and enhancement of the adsorption and activation of *** grown on the surface of InNi alloy not only improves the adsorption of H2and provides sufficient H+for the reaction,but also makes InNi alloy more stable during the reaction *** photothermal effect caused by In2O3accelerates the transfer of photogenerated carriers and increases the surface temperature of the catalyst,thereby synergistically promoting the reaction from a kinetic *** work ameliorates the kinetic and thermodynamic limitations of the photothermal catalytic CO2hydrogenation process through rationally designing the electron transfer direction of the sandwich structured catalysts to parallel way.

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Neural Liénard system: learning periodic manipulation skills through dynamical systems

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Science China(Information Sciences) 2024年第12期67卷 256-271页

作者： haoyu zhang Long CHENG Yu zhang Yifan WANG School of Artificial Intelligence University of Chinese Academy of Sciences State Key Laboratory for Multi-modal Artificial Intelligence Systems Institute of AutomationChinese Academy of Sciences

Learning from demonstrations provides effective methods for teaching robot manipulation ***, capturing periodic manipulation skills remains challenging with the current techniques. To address this gap, we introduce the neural Liénard system(neural LS), a novel neural network framework that utilizes Liénard-type differential equations to create dynamical systems with stable and distinct limit cycles. We also introduce an innovative technique, which not only manages periodic trajectories across various dimensions but also handles trajectories with intersections, enhancing the capability of the robot for complex tasks. We provide a thorough theoretical analysis of neural LS, focusing on its stability and representational *** evaluations show that neural LS achieves superior performance in modeling complex limit cycles,surpassing the existing methods. We particularly emphasize its effectiveness in handling high-dimensional periodic motions and trajectories with intersections. In addition, we explore the adaptability and robustness of neural LS. A practical application involving the Franka Emika robot in a drawing task further demonstrates the real-world utility of neural LS, confirming its effectiveness and potential to equip robots with advanced periodic manipulation skills.

关键词： learning from demonstrations stable dynamical system periodic motions

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Physics-informed machine learning model for prediction of ground reflected wave peak overpressure

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Defence Technology（防务技术） 2024年第11期41卷 119-133页

作者： haoyu zhang Yuxin Xu Lihan Xiao Canjie Zhen State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China Tangshan Research Institute Beijing Institute of TechnologyTangshan 442000China Shandong Special Industry Group Co.Ltd. Zibo 255000China

The accurate prediction of peak overpressure of explosion shockwaves is significant in fields such as explosion hazard assessment and structural protection, where explosion shockwaves serve as typical destructive elements. Aiming at the problem of insufficient accuracy of the existing physical models for predicting the peak overpressure of ground reflected waves, two physics-informed machine learning models are constructed. The results demonstrate that the machine learning models, which incorporate physical information by predicting the deviation between the physical model and actual values and adding a physical loss term in the loss function, can accurately predict both the training and out-oftraining dataset. Compared to existing physical models, the average relative error in the predicted training domain is reduced from 17.459%-48.588% to 2%, and the proportion of average relative error less than 20% increased from 0% to 59.4% to more than 99%. In addition, the relative average error outside the prediction training set range is reduced from 14.496%-29.389% to 5%, and the proportion of relative average error less than 20% increased from 0% to 71.39% to more than 99%. The inclusion of a physical loss term enforcing monotonicity in the loss function effectively improves the extrapolation performance of machine learning. The findings of this study provide valuable reference for explosion hazard assessment and anti-explosion structural design in various fields.

关键词： Blast shock wave Peak overpressure Machine learning Physics-informed machine learning

Dihedral influence on lateral–directional dynamic stability on large aspect ratio tailless flying wing aircraft

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Chinese Journal of Aeronautics 2014年第5期27卷 1149-1155页

作者： Song Lei Yang Hua zhang Yang zhang haoyu Huang Jun School of Aeronautic Science and Engineering Beihang University AVIC The First Aircraft Institute

The influence of dihedral layout on lateral–directional dynamic stability of the tailless flying wing aircraft is discussed in this paper. A tailless flying wing aircraft with a large aspect ratio is selected as the object of study, and the dihedral angle along the spanwise sections is divided into three segments. The influence of dihedral layouts is studied. Based on the stability derivatives calculated by the vortex lattice method code, the linearized small-disturbance equations of the lateral modes are used to determine the mode dynamic characteristics. By comparing 7056 configurations with different dihedral angle layouts, two groups of stability optimized dihedral layout concepts are created. Flight quality close to Level 2 requirements is achieved in these optimized concepts without any electric stability augmentation system.

关键词： Dihedral angle Flying wing Optimization Stability Tailless

Seismic damage to structures in the Ms6.5 Ludian earthquake

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Earthquake Engineering and Engineering Vibration 2016年第1期15卷 173-186页

作者： Chen Hao Xie Quancai Dai Boyang zhang haoyu Chen Hongfu Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering Mechanics CEA Harbin 150080 China Earthquake Administration of Yunnan Province Kunming 650224 China

On 3 August 2014, the Ludian earthquake struck northwest Yunnan Province with a surface wave magnitude of 6.5. This moderate earthquake unexpectedly caused high fatalities and great economic loss. Four strong motion stations were located in the areas with intensity V, VI, VII and IX, near the epicentre. The characteristics of the ground motion are discussed herein, including 1） ground motion was strong at a period of less than 1.4 s, which covered the natural vibration period of a large number of structures; and 2） the release energy was concentrated geographically. Based on materials collected during emergency building inspections, the damage patterns of adobe, masonry, timber frame and reinforced concrete （RC） frame structures in areas with different intensities are summarised. Earthquake damage matrices of local buildings are also given for fragility evaluation and earthquake damage prediction. It is found that the collapse ratios of RC frame and confined masonry structures based on the new design code are significantly lower than non-seismic buildings. However, the RC frame structures still failed to achieve the ＇strong column, weak beam＇ design target. Traditional timber frame structures with a light infill wall showed good aseismic performance.

关键词： Ludian earthquake investigations of seismic damage masonry structure RC frame timber flame adobehouse

Field investigation on severely damaged aseismic buildings in 2014 Ludian earthquake

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Earthquake Engineering and Engineering Vibration 2015年第1期14卷 169-176页

作者： Lin Xuchuan zhang haoyu Chen Hongfu Chen Hao Lin Junqi Institute of Engineering Mechanics China Earthquake Administration Key Laboratory of Earthquake Engineering and Engineering Vibration China Earthquake Administration

The 2014 magnitude 6.5 Ludian earthquake caused a death toll of 617, many landslides and tens of thousands of collapsed buildings. A field investigation to evaluate the damage to buildings was carried out immediately after the occurrence of the earthquake. Severely damaged aseismic buildings, which were basically observed in the downtown of Longtoushan Town, were carefully examined one by one with the aim to improve design codes. This paper summarizes the damage observed to the investigated aseismic buildings in both the structural and local levels. A common failure mode was observed that most of the aseismic buildings, such as RC frame structures and confined masonry structures, were similarly destroyed by severe damage or complete collapse of the first story. The related strong ground motion, which was recorded at the nearby station, had a short duration of less than 20 s but a very large PGA up to 1.0 g. The RC frames based on the new design codes still failed to achieve the design target for ＂strong column, weak beam＂. Typical local failure details, which were related to the interaction between RC columns and infill walls and between constructional columns and masonry walls, are summarized with preliminary analyses.

关键词： Ludian earthquake field investigation aseismic buildings structural collapse local failure

Highly selective photocatalytic CO_(2) reduction to ethylene in pure water by Nb_(2)O_(5) nanoparticles with enriched surface –OH groups under simulated solar illumination

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Journal of Advanced Ceramics 2023年第8期12卷 1641-1654页

作者： haoyu zhang Shuang Gao Haitao Guan Weiyi Yang Qi Li Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Photocatalytic CO_(2) reduction to valuable chemical compounds could be a promising approach for carbon-neutral *** this work,a simple and robust thermal decomposition process was developed with ammonium carbonate((NH4)2CO3)as both precipitation agent and sacrificial template to produce fine Nb_(2)O_(5) nanoparticles with the rich existence of surface hydroxyl(–OH)*** was found by density functional theory(DFT)calculations and experiments that the rich existence of the surface–OH groups enhanced the adsorption of both reactants(CO_(2) and H_(2)O molecules)for the photocatalytic CO_(2) reduction on these fine Nb_(2)O_(5) nanoparticles,and the highly selective conversion of CO_(2) to the high-value chemical compound of ethylene(C_(2)H_(4),~68μmol·g^(−1)·h^(−1) with~100%product selectivity)was achieved under simulated solar illumination without usage of any sacrificial agents or noble metal *** synthesis process may also be readily applied as a surface engineering method to enrich the existence of the surface–OH groups on various metal oxide-based photocatalysts for a broad range of technical applications.

关键词： photocatalytic CO_(2)reduction niobium oxide nanoparticles thermal decomposition surface hydroxyl(-OH)groups simulated solar illumination

FeCoNiCrMo high entropy alloy nanosheets catalyzed magnesium hydride for solid-state hydrogen storage

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2270-2279页

作者： Tao Zhong haoyu zhang Mengchen Song Yiqun Jiang Danhong Shang Fuying Wu Liuting zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China Max Planck Institute for Iron Research Düsseldorf40237Germany School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The catalytic effect of FeCoNiCrMo high entropy alloy nanosheets on the hydrogen storage performance of magnesium hydride(MgH_(2))was investigated for the first time in this *** results demonstrated that 9wt%FeCoNiCrMo doped MgH_(2)started to dehydrogenate at 200℃and discharged up to 5.89wt%hydrogen within 60 min at 325℃.The fully dehydrogenated composite could absorb3.23wt%hydrogen in 50 min at a temperature as low as 100℃.The calculated de/hydrogenation activation energy values decreased by44.21%/55.22%compared with MgH_(2),***,the composite’s hydrogen capacity dropped only 0.28wt%after 20 cycles,demonstrating remarkable cycling *** microstructure analysis verified that the five elements,Fe,Co,Ni,Cr,and Mo,remained stable in the form of high entropy alloy during the cycling process,and synergistically serving as a catalytic union to boost the de/hydrogenation reactions of MgH_(2).Besides,the FeCoNiCrMo nanosheets had close contact with MgH_(2),providing numerous non-homogeneous activation sites and diffusion channels for the rapid transfer of hydrogen,thus obtaining a superior catalytic effect.

关键词： hydrogen storage magnesium hydride high entropy alloy nano-sheets catalysis

Recent advances of magnesium hydride as an energy storage material

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Journal of Materials Science & Technology 2023年第18期149卷 99-111页

作者： Mengchen Song Liuting zhang Fuying Wu haoyu zhang Hu Zhao Lixin Chen Hong Li School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China School of Mechanical and Aerospace Engineering Nanyang Technological University639798Singapore State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

Energy storage is the key for large-scale application of renewable energy,however,massive efficient en-ergy storage is very *** hydride(MgH_(2))offers a wide range of potential applications as an energy carrier due to its advantages of low cost,abundant supplies,and high energy storage ***,the practical application of MgH_(2) for energy storage is still impeded by its sluggish kinetics,poor cycling stability,***,we provide an overview of recent advances of MgH_(2) for enhancing the hydrogen storage,lithium-ion storage,and heat storage *** hydrogen storage,a particular emphasis was put on altering the kinetics and thermodynamics of MgH_(2) via catalyzing,alloying,nano-sizing,and *** to MgH_(2) as a battery anode material mainly focus on the effect of additives,electrolytes,and structure *** heat storage apparatus was proposed based on MgH_(2) and coupled with other materials or systems to improve the heat storage and economic ***,prospects of MgH_(2) in these fields are *** review would stimulate more insightful and pioneering research for the design and preparation of MgH_(2) with excellent energy storage performances.

关键词： Magnesium hydride Energy storage Hydrogen storage Li-ion battery Heat storage

Radial electromagnetic type unbalance vibration self-recovery regulation system for high-end grinding machine spindles

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Frontiers of Mechanical Engineering 2023年第3期18卷 203-217页

作者： Xin PAN haoyu zhang Jinji GAO Congcong XU Dongya LI Beijing Key Laboratory of Health Monitoring and Self-recovery for High-end Mechanical Equipment Beijing University of Chemical TechnologyBeijing 100029China Luoyang Bearing Research Institute Corporation Luoyang 471033China

Modern rotating machines,which are represented by high-end grinding machines,have developed toward high precision,intelligence,and high durability in recent *** the core components of grinding machine spindles,grinding wheels greatly affect the vibration level during *** unbalance vibration self-recovery regulation(UVSRR)system is proposed to suppress the vibration of grinding wheels during workpiece processing,eliminating or minimizing the ***,technical principles and the system composition are ***,the balancing actuator in the UVSRR system is analyzed in *** advanced nature of the improved structure is presented through structure introduction and advantage *** performance of the balancing actuator is mutually verified by the theoretical calculation of torque and software *** show that the self-locking torque satisfies the actual demand,and the driving torque is increased by 1.73 times compared with the traditional ***,the engineering application value of the UVSRR system is verified by laboratory performance comparison and actual factory *** balancing speed and effect of the UVSRR system are better than those of an international mainstream product and,the quality of the workpieces machined in the factory improved by 40%.

关键词： SUVSRRR system radial electromagnetic type vibration suppression performance simulation engineering application