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microstructure and Wear Behaviour of Laser-induced thermite Reaction Al_2O_3 Ceramic Coating on AA7075 Aluminum Alloy

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Journal of materials Science & technology 2007年第2期23卷 201-206页

作者： Kaijin HUANG Xin LIN Changsheng XIE t.m. yue State Key Laboratory of Plastic Forming Simulation and mould technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Solidification Processing Northwestern Polytechnic University Xi＇an 710072 China Department of Industrial and Syst.m. Engineering Hong Kong Polytechnic University Hung Hom Hong Kong China

the microstructure and wear behaviour of the thermite reaction coating produced by the hybrid laser claddingremelting on AA7075 aluminum alloy for the syst.m. of Al-CuO-SiO2, Al-Cr2O3-SiO2, Al-Fe2O3-SiO2, and Al-tiO2-SiO2 were studied. the results of the X-ray diffraction （XRD） analysis show that in all the four reaction coatings, α-Al2O3 and γ-Al2O3 phases were present at the top surface, together with various intermetallic phases, the corresponding reduced metal and Al phase in the fusion zone. Under the dry sliding condition, the wear resistance, in terms of weight loss, of the laser-clad specimens was considerably higher than that of the untreated specimen. the predominant wear mechanism of the former specimens was abrasive wear, while for the latter, it was the adhesive wear that prevailed.

关键词： Laser cladding thermite reaction Aluminum alloy Wear

Product Form Solution of a Queuing-Inventory Syst.m.with Lost Sales and Server Vacation

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Journal of Syst.m. Science & Complexity 2024年第2期37卷 729-758页

作者： yue Dequan ZHANG Yuying XU Xiuli yue Wuyi School of Science Yanshan UniversityQinhuangdao 066004China School of Economics and management Yanshan UniversityQinhuangdao 066004China the Kyoto College of Graduate Studies for Informatics Kyoto City 606-8225Japan

In this study,the authors consider an m/m/1 queuing syst.m.with attached inventory under an(s,S)control *** server takes multiple vacations whenever the inventory is *** is assumed that the lead t.m. and the vacation t.m. follow exponential *** authors formulate the model as a quasi-birth-and-dearth(QBD)process and derive the stability condition of the ***,the stationary distribution in product form for the joint process of the queue length,the inventory level,and the server’s status is ***,the conditional distributions of the inventory level when the server is on and operational,and when it is off due to a vacation,are *** the stationary distribution,the authors obtain some performance measures of the *** authors investigate analytically the effect of the server’s vacation on the performance ***,several numerical examples are presented to investigate the effects of some parameters on the performance measures,the opt.m.l policy,and the opt.m.l cost.

关键词： Cost function multiple vacations product form solution queuing-inventory system (s S)control policy

Deciphering the controlling factors for phase transitions in zeolitic imidazolate frameworks

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National Science Review 2024年第4期11卷 151-163页

作者： tao Du Shanwu Li Sudheer Ganisetti mathieu Bauchy Yuanzheng yue morten m.Smedskjaer Department of Chemistry and Bioscience Aalborg University Department of mechanical Engineering-Engineering mechanics Michigan Technological University Physics of Amo Rphous and Inorganic Solids Laboratory(PARISlab) Department of Civil and Environmental EngineeringUniversity of CaliforniaLos Angeles

Zeolitic imidazolate frameworks（ZIFs） feature complex phase transitions, including polymorphism,melting, vitrification, and polyamorphism. Experimentally probing their structural evolution during transitions involving amorphous phases is a significant challenge, especially at the medium-range length scale. to overcome this challenge, here we first train a deep learning-based force field to identify the structural characteristics of both crystalline and non-crystalline ZIF phases. this allows us to reproduce the structural evolution trend during the melting of crystals and formation of ZIF glasses at various length scales with an accuracy comparable to that of ab initio molecular dynamics, yet at a much lower computational cost. Based on this approach, we propose a new structural descriptor, namely, the ring orientation index, to capture the propensity for crystallization of ZIF-4(Zn（Im）2, Im = C3H3N2-) glasses, as well as for the formation of ZIF-zni(Zn（Im）2) out of the high-density amorphous phase. this crystal formation process is a result of the reorientation of imidazole rings by sacrificing the order of the structure around the zinc-centered tetrahedra. the outcomes of this work are useful for studying phase transitions in other metal-organic frameworks（mOFs） and may thus guide the development of mOF glasses.

关键词： metal-organic frameworks phase transitions melting glass formation transferable deep learning force field ring orientation

Solar evaporation for simultaneous oil-water separation and electricity generation with Janus wood-based absorbers

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 13-23页

作者： yue Yang Ze Fu Qi Zhang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science&TechnologyNanjing 210094China Key Laboratory of Industrial Ecology and Environmental Engineering(ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National Laboratory of Solid State microstructures Collaborative Innovation Center of Advanced MicrostructuresCollege of Engineering and Applied SciencesKey Laboratory of Intelligent Optical Sensing and Manipulation(Ministry of Education)Jiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210093China

Oily wastewater from ocean oil spills endangers marine ecosyst.m. and human health. therefore, developing an effective and sustainable solution for separating oil-water mixtures is urgent. Interfacial solar photothermal evaporation is a promising approach for the complete separation of two-phase mixtures using only solar energy. Herein, we report a carbonized wood-based absorber with Janus structure of comprising a hydrophobic top-layer and an oleophobic bott.m.layer for simultaneous solar-driven oil-water separation and electricity generation. Under sunlight irradiation, the rapid evaporation of seawater will induce a separation of oil-water mixtures, and cause a high salt concentration region underlying the interface, while the bott.m.“bulk water” maintains in a low salt concentration, thus forming a salinity gradient. Electricity can be generated by salinity gradient power. therefore, oil-water separation efficiency of > 99% and derived extra electricity power of ~0.1 W/m2 is achieved under solar radiation, demonstrating the feasibility of oil-water separation and electricity production synchronously directly using solar energy. this work provides a green and cost-effective path for the separation of oil-water mixtures.

关键词： Oily wastewater Carbonized wood Salinity gradient Electricity generation Solar irradiation

EPR-Net: constructing a non-equilibrium potential landscape via a variational force projection formulation

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National Science Review 2024年第7期11卷 135-147页

作者： yue Zhao Wei Zhang tiejun Li Center for Data Science Peking University Zuse Institute Berlin Department of mathematics and Computer Science Freie Universit?t Berlin Laboratory of mathematics and Applied mathematics(LmAm)and School of mathematical Sciences Peking University Center for machine Learning Research Peking University

We present EPR-Net, a novel and effective deep learning approach that tackles a crucial challenge in biophysics: constructing potential landscapes for high-dimensional non-equilibrium steady-state ***-Net leverages a nice mathematical fact that the desired negative potential gradient is simply the orthogonal projection of the driving force of the underlying dynamics in a weighted inner-product ***, our loss function has an int.m.te connection with the steady entropy production rate(EPR),enabling simultaneous landscape construction and EPR est.m.tion. We introduce an enhanced learning strategy for syst.m. with small noise, and extend our framework to include dimensionality reduction and the state-dependent diffusion coefficient case in a unified fashion. Comparative evaluations on benchmark problems demonstrate the superior accuracy, effectiveness and robustness of EPR-Net compared to existing methods. We apply our approach to challenging biophysical problems, such as an eight-dimensional(8D)limit cycle and a 52D multi-stability problem, which provide accurate solutions and interesting insights on constructed landscapes. With its versatility and power, EPR-Net offers a promising solution for diverse landscape construction problems in biophysics.

关键词： high-dimensional potential landscape non-equilibrium system entropy production rate dimensionality reduction deep learning

Spatio-t.m.oral Evaluation of multi-scale Cultivated Land Syst.m.Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China

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Chinese Geographical Science 2024年第1期34卷 168-180页

作者： WANG yue JIANG Yuting ZHU Guoxu School of management Shenyang Normal UniversityShenyang110034China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130012China

It is of great significance to syst.m.tically analyze the cultivated land syst.m.resilience(CLSR) for the black soil protection and national food *** CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food *** is urgent to evaluate the CLSR at.m.ltiple spatio-t.m.oral *** study took Liaoning Province in the black soil region of Northeast China as an *** on the resilience theory,this study constructed the CLSR evaluation syst.m.from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to *** results showed that:1) the t.m. series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) the CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) there were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,*** addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the *** feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the *** results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment.

关键词： cultivated land syst.m.resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province,China

Interface structure of α-mg/14H-LPSO:First-principles prediction and experimental study

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Journal of Rare Earths 2024年第9期42卷 1792-1799,I0006页

作者： Yuan Shi Xiaohua Zhang Hongyan yue Chao Li School of materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040China

the interfacial structure of the α-mg/14H-LPSO phase in rare earth-including magnesium alloy was investigated via high-angle annular dark-field scanning transmission electron microscopy(HAADFSt.m. imaging and first-principles calculations of density-functional *** possible interfacial models were constructed according to the different terminations of the LPSO phase,and the corresponding interfacial energies were calculated,from which the four most stable structures(terl-mgY-hollow,ter2-Zn-hollow,ter3-mgYII-hollow and ter4-mg-bridge) were *** interfacial phase diagrams related to the Y chemical potentials were obtained from the calculations,and the most stable interfacial structure was ***-mgY-hollow and ter2-Zn-hollow have the lowest interfacial energies in the range of-0.7 eV tuating change of state is the minimized and the interface is the most *** separation work of the two models was calculated to predict the bonding strength of the structures at both ends of the *** calculation results show that the maximum interfacial separation work is 1.45 J/m^(2) for the interface model of α-mg and 14H-LPSO phase structure with ter2-Zn-hollow termination.

关键词： Rare earths magnesium alloy HAADF-StEm LPSO First-principles Interface

micro-flow structure at regime transition from bubbling to turbulent fluidization in a fluidized bed

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Particuology 2024年第6期89卷 117-130页

作者： Chaoyu Yan yue Yuan Xiaoyang Wei Jesse Zhu State Key Laboratory of Heavy Oil Processing Beijing Key Laboratory of Process Fluid Filtration and SeparationCollege of Mechanical and Transportation EngineeringChina University of PetroleumBeijing 102249China China Beacons Institute The University of NottinghamNingbo315100China Department of Chemical and Biochemical Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

Gas-solid fluidized beds have found extensive utilization in frontline manufacturing,in particular as low-velocity *** fluidization status,the bubbling or turbulent flow regime and the transition in between,determine the syst.m.performance in practical *** the convoluted hydrodynamics are quantitively evaluated through numerous data-processing methodologies,none of them alone can reflect all the critical information to identify the transition from the bubbling to the turbulent ***,this study was to exploit a coupling data processing methodology,in the combination of standard deviation,power spectrum density,probability density function,wavelet transform,and wavelet.m.ltiresolution method,to jointly explain the micro-flow structure at the regime transition from bubbling to turbulent *** transient differential pressure fluctuation was measured for the evaluation in a fluidized bed(0.267 m i.d.×2.5 m height)with FCC catalysts(d_(p)=65μm,ρ_(p)=1780kg/m^(3))at different superficial gas velocities(0.02–1.4 m/s).the results show that the onset of turbulent fluidization starts earlier in the top section of the bed than in the bott.m.*** wavelet decomposition displays that the fluctuation of differential pressure mainly concentrates on the sub-signals with an intermediate frequency *** sub-signals could be synthesized into three types of scales(micro-scale,meso-scale,and macro-scale),representing the multi-scale hydrodynamics in the fluidized *** micro-scale signal has the characteristic information of bubbling fluidization,and the characteristic information of turbulent fluidization is mainly represented by the meso-scale *** work provides a syst.m.tic comprehension of fluidization status assessment and serves as an impetus for more coupling analysis in this sector.

关键词： Flow regime transition Bubbling fluidization turbulent fluidization micro-flow structure Differential pressure fluctuation

Analytical Expression for the At.m.c Friction of a Single Asperity Based on the Prandtl-t.m.inson model

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Acta mechanica Solida Sinica 2024年第3期37卷 416-422页

作者： Weike Yuan yue Ding Gangfeng Wang Xinrui Niu Department of Engineering mechanics SVLMMLXi’an Jiaotong UniversityXi’an710049China Department of mechanical Engineering City University of Hong KongHong Kong SAR999077China

the Prandtl-t.m.inson(Pt.m.del has been widely applied to interpret the at.m.c friction mechanism of a single *** this study,we present an approximate explicit expression for the friction force in the one-dimensional Pt.m.del under quasi-static ***‘stick-slip’friction curves are first approximated properly by sawtooth-like lines,where the critical points before and after the‘slip’motion are described analytically in terms of a dimensionless parameterη.Following this,the average friction force is expressed in a closed form that remains continuous and valid forη>***,an analytical expression for the load dependence of at.m.c friction of a single asperity is derived by connecting the parameterηwith the normal *** the parameters reported in experiments,our prediction shows good agreement with relevant experimental results.

关键词： At.m.c friction Stick-slip friction Prandtl-t.m.inson model Friction force microscope