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Sequestration of helium and xenon via iron-halide compounds in early Earth

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matter and Radiation at Extremes 2024年第3期9卷 83-88页

作者： Jurong Zhang Hanyu Liu Changfeng Chen Yanming ma Key laboratory of material Simulation Methods and Software of Ministry of Education and State Key laboratory of Superhard materials College of PhysicsJilin UniversityChangchun 130012China School of Physics and Electronics Shandong Normal UniversityJinan 250014China International Center of Future Science Jilin UniversityChangchun 130012China Department of Physics and Astronomy University of NevadaLas VegasNevada 89154USA

The terrestrial abundance anomalies of helium and xenon suggest the presence of deep-Earth reservoirs of these elements,which has led to great interest in searching for materials that can host these usually unreactive ***,using an advanced crystal structure search approach in conjunction with first-principles calculations,we show that several Xe/He-bearing iron halides are thermodynamically stable in a broad region of P–T phase space below 60 *** results present a compelling case for sequestration of He and Xe in the early Earth and may suggest their much wider distribution in the present Earth than previously *** findings offer insights into key material-based and physical mechanisms for elucidating major geological phenomena.

关键词： halide searching insight

Research Progress on Bionic Water Strider Robots

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Journal of Bionic Engineering 2024年第2期21卷 635-652页

作者： Jianhao Liu Mingjun Shen Ziqiang ma Xinping Zhou School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan430074China State Key laboratory of Intelligent manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

Biological water striders have advantages such as flexible movement,low disturbance to the water surface,and low *** have developed a large number of biomimetic water strider robots based on their movement mechanism,which have broad application prospects in water quality testing,water surface reconnaissance,and *** article mainly reviews the research progress of biomimetic water strider ***,the biological and kinematic characteristics of water striders are outlined,and some mechanical parameters of biological water striders are *** basic equations of water strider movement are then ***,an overview is given of the past and current work on skating and jumping movements of biomimetic water strider robots based on surface tension and water pressure *** on the current research status of biomimetic water strider robots,the shortcomings of current research on biomimetic water striders are summarized,and the future development of biomimetic water strider robots is *** article provides new insights for the design of biomimetic water strider robots.

关键词： Bionics Water strider Robot Motion of robots on water surface

Strong shock propagation for the finite-source circular blast in a confined domain

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Applied mathematics and Mechanics(English Edition) 2024年第6期45卷 1071-1084页

作者： Qihang ma Kaileong CHONG Bofu WANG Quan ZHOU Shanghai Key laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

The circular explosion wave produced by the abrupt discharge of gas from a high-temperature heat source serves as a crucial model for addressing explosion phenomena in compressible *** reflection of the primary shock and its propagation within a confined domain are studied both theoretically and numerically in this *** the assumption of strong shock,the scaling law governing propagation of the main shock is *** dimensionless frequency of reflected shock propagation is associated with the confined *** numerical simulation for the circular explosion problem in a confined domain is performed for *** the influence of confinement,the principal shock wave systematically undergoes reflection within the domain until it weakens,leading to the non-monotonic attenuation of kinetic energy in the explosion fireball and periodic oscillations of the fireball volume with a certain *** simulation results indicate that the frequency of kinetic energy attenuation and the volume oscillation of the explosive fireball align consistently with the scaling law.

关键词： explosion confinement main shock frequency

Investigation on the Velocity-Dependent Adhesion Hysteresis via Molecular Dynamics Simulation

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Acta Mechanica Solida Sinica 2024年第3期37卷 423-429页

作者： Jinshan He Yiran Li Zhaoyang ma Ganyun Huang Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin300350China

Adhesion plays an important role in miniaturized devices and technologies,which depends not only on indentation depth but also on the history of contact making and breaking,giving rise to adhesion *** the present work,adhesion hysteresis has been investigated via molecular dynamics simulations on approaching and retracting a rigid tip to and from a *** results show that hysteresis in the force-displacement curve that depends on approaching and retraction velocities arises under both elastic and plastic *** underlying mechanisms have been *** implications of the results in friction have been discussed briefly.

关键词： Adhesion hysteresis Molecular dynamics simulation Contact instability Plastic deformation

Preparation of K-doped g-C_(3)N_(4) composite loaded on magnetic attapulgite and its degradation performance for malachite green

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Chinese Journal of Chemical Engineering 2024年第7期71卷 110-121页

作者： Aishun ma Hanlin Qian Hongxia Liu Sili Ren Jiangxi Key laboratory of Mining&Metallurgy Environmental Pollution Control Jiangxi University of Science and TechnologyGanzhou 341000China Jiangxi Provincial Key laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources Jiangxi University of Science and TechnologyGanzhou 341000China

Visible-light-driven photocatalysis is a promising technology for the treatment of dye *** this work,a novel photocatalyst of K-doped g-C_(3)N_(4) loaded on magnetic attapulgite(ATP)(Kω-g-C_(3)N_(4)@ATP-Fe_(3)O_(4))with excellent visible light photocatalytic properties and stability were successfully prepared and *** removal efficiency of Kω-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) for malachite green(MG)was studied,and the degradation mechanism was analyzed and *** was found that the K_(5)-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) photocatalyst possessed excellent degradation efficiency of over 98.0%for the MG dye wastewater under optimal ***,the K_(5)-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) materials possessed good recyclability with a removal rate over 82%after 4 *** visible light condition,the K_(5)-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) photocatalyst produce radicals of·OH and O_(2)^(-)to degrade the MG dyes,which was supported by electron paramagnetic resonance(EPR)and radical trapping *** addition,the LC-MS analysis interpreted the degradation pathways and intermediates of MG in the *** findings in this work indicate that the prepared photocatalytic material has excellent degradation efficiency for MG and can be applied in dye wastewater treatment.

关键词： Photocatalyst malachite green K-doped g-C_(3)N_(4) Degradation

A review of vehicle detection methods based on computer vision

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Journal of Intelligent and Connected Vehicles

Journal of Intelligent and Connected Vehicles 2024年第1期7卷 1-18页

作者： Changxi ma Fansong Xue School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou 730070China Key laboratory of Railway Industry on Plateau Railway Transportation Intelligent management and Control Lanzhou 730070China

With the increasing number of vehicles,there has been an unprecedented pressure on the operation and maintenance of intelligent transportation systems and transportation *** order to achieve faster and more accurate identification of traffic vehicles,computer vision and deep learning technology play a vital role and have made significant *** study summarizes the current research status,latest findings,and future development trends of traditional detection algorithms and deep learning-based detection *** the detection algorithms based on deep learning,this study focuses on the representative convolutional neural network ***,it examines the two-stage and one-stage detection algorithms,which have been extensively utilized in the field of intelligent transportation *** to traditional detection algorithms,deep learning-based detection algorithms can achieve higher accuracy and *** single-stage detection algorithm is more efficient for real-time detection,while the two-stage detection algorithm is more accurate than the single-stage detection *** the follow-up research,it is important to consider the balance between detection efficiency and detection ***,vehicle missed detection and false detection in complex scenes,such as bad weather and vehicle overlap,should be taken into *** will ensure better application of the research findings in engineering practice.

关键词： intelligent transportation system computer vision deep learning vehicle detection object detection algorithm

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： Qian ma Peng Jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil

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International Journal of Minerals,Metallurgy and materials 2024年第6期31卷 1241-1248页

作者： Chen Li Wenhui ma Yang Li Kuixian Wei Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical *** involves systematic and theoretical engineering technology for utilizing planetary resources in ***,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the *** this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil *** microstructural characteristics of the lunar soil may drastically change its metallurgical *** main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral *** nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar *** ions injected by solar wind may promote the hydrogen reduction *** widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar ***,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar *** is a property that earth samples and tradi-tional simulated lunar soil *** application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil.

关键词： space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance

Further Results on Stability Analysis for Sampled-Data Systems via Refined Semi-Looped-Functional

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Journal of Systems Science & Complexity 2024年第1期37卷 318-328页

作者： SHENG Zhaoliang XU Shengyuan ma Qian ZHANG Baoyong School of Automation Nanjing University of Science and TechnologyNanjing 210094China

This paper investigates the stability problem for sampled-data systems by adopting a refined semi-looped-functional,which is with the following two ***,the new functional term is with a new integral vectorη0,which contains sampling information of the systems and associates two commonly used ***,the vectorη0 is combined into various zero equations for processing the functional,especially where a new equation is derived fromη*** on the refined functional,further stability results for sampled-data systems are *** the effectiveness of the results is numerically verified through two examples at the end.

关键词： Integral vector sampled-data systems semi-looped-functional stability analysis.