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A Review on Particle Reinforced Mg Matrix Composites Fabricated by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 391-400页

作者： Zhiyuan liu Li Jin Jian Zeng Fulin Wang Fenghua Wang Shuai Dong jie Dong National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper provides a comprehensive review of research progress in particle-reinforced Mg matrix composites prepared via powder *** article discusses different strategies,such as micro-sized,nano-sized particles,and multi-particle hybridization,which has been employed to enhance the performance of the *** addition,a range of preparation techniques that optimize the dispersion of the reinforcing particles are *** paper also highlights how the different configurations between the reinforcements and matrix alloy impact the composites’***,the article outlines the prospects of particles reinforced Mg matrix composites fabricated via powder metallurgy and recommends modification methods that could be explored to further develop these materials for various applications.

关键词： Magnesium matrix composites Reinforcing particle Powder metallurgy Mechanical properties Configuration

An Integral Method for Solving Dynamic Equations with Fluid–Solid Coupling

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Acta Mechanica Solida Sinica 2024年第1期37卷 99-108页

作者： Xin Zhang jie liu Pu Xue Shuowen Yan Yahao Xu M.S.Zahran School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Civil Engineering Military Technical CollegeCairo 11435Egypt

In this work,a new methodology is presented to mainly solve the fluid–solid interaction(FSI)*** methodology combines the advantages of the Newmark precise integral method(NPIM)and the dual neural network(DNN)*** NPIM is employed to modify the exponential matrix and loading vector based on the DNN integral *** involves incorporating the basic assumption of the Newmark-βmethod into the dynamic equation and eliminating the acceleration term from the dynamic equilibrium *** a result,the equation is reduced to a first-order linear equation ***,the PIM is applied to integrate the system step by step within the *** DNN method is adopted to solve the inhomogeneous term through fitting the integrand and the original function with a pair of neural networks,and the integral term is solved using the Newton–Leibniz *** examples demonstrate that the proposed methodology significantly improves computing efficiency and provides sufficient precision compared to the DNN *** is particularly evident when analyzing large-scale structures under blast loading conditions.

关键词： Newmark precise integral method(NPIM) Dual neural networks(DNN) Fluid-solid interaction(FSI) Dynamic time-history analysis Blast loading

Flame Structure of Methane and Kerosene Combustion with a Compact Concave Flame-Holder using the LES-pdf Method

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Journal of Thermal Science 2024年第1期33卷 222-234页

作者： WANG Fang WANG Yunfan WEI Guanyi liu Denghuan JIN jie JONES P.William School of Energy and Power Engineering Beihang UniversityBeijingBeijing 100191China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Compact flame-holders for afterburners are an increasing requirement for modern aero ***,flame-holder design is non-trivial since high inlet temperatures,velocities,and elaborate structures induce complex turbulence,combustion,and spray coupling in modern *** this work,the LES-pdf and stochastic fields-Lagrangian particle spray methods are used to investigate methane and aviation kerosene combustion structures formed by new-type concave *** flow pattern,combustion mode,and flame structure of gaseous and liquid fuel around a concave flame-holder are analyzed,discussed,and compared with experimental *** reveal that the flame stability of a concave flame-holder is better than that of the non-concave ***,when using liquid fuel,the concave flame-holder forms a stable and compact *** results suggest concave flame-holders are a promising design for compact afterburners.

关键词： concave structure flame-holder LES-pdf spray combustion flame structure AECSC

Effect of austenitizing condition on mechanical properties,microstructure and precipitation behavior of AISI H13 steel

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Journal of Iron and Steel Research(International) 2024年第1期31卷 143-156页

作者： An-gang Ning Yang liu Rui Gao Stephen Yue Ming-bo Wang Han-jie Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Department of Mining and Materials Engineering McGill UniversityMontrealQCH3A 0C5Canada ASSAB Tooling Technology(Chongqing)Co. Ltd.Chongqing401120China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The effects of austenitizing temperature(1223,1303,and 1373 K)and holding time(1-1500 s)on the microstructure,mechanical properties,and precipitation behavior of the H13 hot work die steel were *** results indicate a softening phenomenon when H13 steel is austenitized at 1303 K beyond 900 s and 1373 K beyond 600 s,*** the sample held for 1200 s,the tensile strength is found capable of reaching up to 2.2 GPa when quenched from a temperature above 1303 ***,prior-austenite grain size increases with the increase in austenitizing *** kinetic behavior of the precipitates(mainly MC-type carbides)in H13 steel could be elaborated through the principles set forth by the Arrhenius and Avrami ***,the comprehensive strengthening of the H13 steel was discussed in *** results show that the activation energy of the transformed fraction of carbides is higher than that of the diffusion process for common alloying elements(Cr,V,Mo,and Ni)found in the *** suggests that it would be difficult for precipitates to dissolve into the matrix when H13 steel is austenitized at high *** the increasing austenitizing temperature,the precipitation fraction decreases,and the dislocation density *** dislocation strengthening is regarded as the dominant strengthening contributed to yield strength in as-quenched H13 steel.

关键词： H13 steel Austenitizing Mechanical property Precipitation behavior Comprehensive strengthening

Anti-abrasion collagen fiber-based membrane functionalized by UiO-66-NH_(2)with ultra-high efficiency and stability for oil-in-water emulsions separation

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Chinese Journal of Chemical Engineering 2024年第2期66卷 285-297页

作者： Xiaoxia Ye Rixin Huang Zhihong Zheng Juan liu jie Chen Yuancai Lv College of Environmental and Safety Engineering Fuzhou UniversityFuzhou 350108China College of Chemical Engineering Fuzhou UniversityFuzhou 350108China

Membrane separation strategies offer promising platform for the emulsion ***,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant *** this study,we report a CFM@UiO-66-NH_(2)membrane with high separation flux,efficiency and stability,through utilizing a robust anti-abrasion collagen fiber membrane(CFM)as the multifunctional support and UiO-66-NH_(2)by an in-situ growth as the separation *** high mechanical strength of the CFM compensated for the weakness of the separation layer,while the charge-breaking effect of UiO-66-NH_(2),along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers,contributed to the potential for efficient ***,the CFM@UiO-66-NH_(2)membrane exhibited superhydrophilic properties,making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic *** membrane demonstrated remarkable separation efficiencies of up to 99.960%and a separation flux of370.05 L·m^(-2)·h^(-1).Moreover,it exhibits stability,durability,and abrasion resistance,maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and *** six cycles of reuse,it achieved a separation flux of 417.97 L·m^(-2)·h^(-1)and a separation efficiency of 99.747%.Furthermore,after undergoing 500 cycles of strong abrasion,the separation flux remained at 124.39 L·m^(-2)·h^(-1),with a separation efficiency of 99.992%.These properties make it suitable for the long-term use in harsh operating *** attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH_(2)and its in-situ growth on the CFM,which forms a size-screening separation *** work highlights the potential of the CFM@UiO-66-NH_(2)membrane as an environmentally friendly size-screening

关键词： Collagen fibers Metal-organic frameworks Oil-in-water emulsion separation Size sieving

On the Intelligent Optimization of the Crevice Structure in a Rapid Compression Machine

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Journal of Thermal Science 2024年第3期33卷 1200-1215页

作者： GUO Qiang liu jie WU Yingtao WANG Hewu TANG Chenglong YU Ruiguang Department of Power Mechanical Engineering Beijing Jiaotong UniversityBeijing100044China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing100084China Beijing Key Laboratory of New Energy Vehicle Powertrain Technology Beijing100044China National International Science and Technology Cooperation Base Beijing Jiaotong UniversityBeijing100044China

In this study,the multi-objective intelligent optimization of the crevice structure in a rapid compression machine(RCM)is carried out based on the RCM simulation model modified with the KIVA-3V program.A multi-objective optimization simulation model of the crevice structure based on the large eddy simulation model coupled with the genetic algorithm NSGA-Ⅲis *** optimization parameters and seven optimization objectives are selected in the optimization *** results show that the genetic algorithm can quickly find the values of the optimized *** crevice volume ratio shows a trade-off relationship with the dimensionless temperature ratio T_(max)/T_(aver)and the tumble ratio.A larger crevice volume can reduce the flow of boundary layer cryogenic gas into the combustion chamber,thus improving the temperature *** addition,the crevice entrance width and the connecting channel length should be smaller,while the volume of the crevice main chamber should be larger,so as to sufficiently introduce the low-temperature gas of the boundary layer into the crevice and reduce their influence on the temperature field of the combustion *** the crevice volume accounts for10%of the total volume,the temperature uniformity of the combustor is significantly enhanced,and when the crevice volume accounts for 30.4%,there is almost no low-temperature vortex in the combustion chamber.

关键词： rapid compression machine adiabatic core area ignition delay period crevice structure

ST-LSTM-SA:A New Ocean Sound Velocity Field Prediction Model Based on Deep Learning

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Advances in Atmospheric Sciences 2024年第7期41卷 1364-1378页

作者： Hanxiao YUAN Yang liu Qiuhua TANG jie LI Guanxu CHEN Wuxu CAI First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Key Laboratory of Oceanic Surveying and Mapping Ministry of Natural ResourcesQingdao 266061China

The scarcity of in-situ ocean observations poses a challenge for real-time information acquisition in the *** the crucial hydroacoustic environmental parameters,ocean sound velocity exhibits significant spatial and temporal variability and it is highly relevant to oceanic *** this study,we propose a new data-driven approach,leveraging deep learning techniques,for the prediction of sound velocity fields(SVFs).Our novel spatiotemporal prediction model,STLSTM-SA,combines Spatiotemporal Long Short-Term Memory(ST-LSTM) with a self-attention mechanism to enable accurate and real-time prediction of *** circumvent the limited amount of observational data,we employ transfer learning by first training the model using reanalysis datasets,followed by fine-tuning it using in-situ analysis data to obtain the final prediction *** utilizing the historical 12-month SVFs as input,our model predicts the SVFs for the subsequent three *** compare the performance of five models:Artificial Neural Networks(ANN),Long ShortTerm Memory(LSTM),Convolutional LSTM(ConvLSTM),ST-LSTM,and our proposed ST-LSTM-SA model in a test experiment spanning 2019 to *** results demonstrate that the ST-LSTM-SA model significantly improves the prediction accuracy and stability of sound velocity in both temporal and spatial *** ST-LSTM-SA model not only accurately predicts the ocean sound velocity field(SVF),but also provides valuable insights for spatiotemporal prediction of other oceanic environmental variables.

关键词： sound velocity field spatiotemporal prediction deep learning self-allention

A new TiO_(2) nanorods/MoTe_(2) quantum dots/Al_(2)O_(3) composite photocatalyst for efficient photoelectrochemical water splitting under simulated sunlight

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Frontiers of Materials Science 2024年第2期18卷 61-74页

作者： jie Meng Hongmei liu Sainan Zhang Baogui Ye Min Feng Daoai Wang School of Chemistry and Chemical Engineering Lanzhou Jiaotong UniversityLanzhou 730000China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Qingdao Centerof Resource Chemistry and New Materials Qingdao 266100China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 265503China

The solar-to-hydrogen conversion using the photoelectrochemical(PEC)method is a practical approach to producing clean ***,it relies on the availability of photocatalyst *** this work,a novel photocatalyst comprising molybdenum telluride quantum dots(MoTe_(2) QDs)-modified titanium dioxide nanorods(TiO_(2) NRs)was prepared for the enhancement of the PEC water splitting performance after combination with a Al_(2)O_(3) layer using the atomic layer deposition(ALD)***_(2) QDs were initially prepared,and then they were loaded onto TiO_(2) NRs using a warm water bath-based heating *** a layer of Al_(2)O_(3) was deposited onto resulted TiO_(2) NRs/MoTe_(2) QDs,the composite TiO_(2) NRs/MoTe_(2) QDs/Al_(2)O_(3) was finally *** simulated sunlight(100 mW·cm^(-2)),such a composite exhibited a maximum photocurrent density of 2.25 mA·cm^(-2) at 1.23 V(versus RHE)and an incident photon-to-electron conversion efficiency of 69.88%at 380 nm,which are 4.33 and 6.66 times those of pure TiO_(2) NRs,***,the composite photocatalyst fabricated in this work may have promising application in the field of PEC water splitting,solarcells andotherphotocatalyticdevices.

关键词： MoTe_(2)quantum dot TiO_(2)nanorod Al_(2)O_(3) atomic layer deposition photoelectrochemistry

Experimental study on the effect of water absorption level on rockburst occurrence of sandstone

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 136-152页

作者： Dongqiao liu jie Sun Pengfei He Manchao He Binghao Cao Yuanyuan Yang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China Institute for Deep Underground Science and Engineering China University of Mining and Technology(Beijing)Beijing100083China

To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single ***-speed photography and acoustic emission(AE)system are used to monitor the rockburst *** effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure *** results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of *** is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is *** the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to *** prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation.

关键词： Rockburst Water Prevention effect Crack evolution