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Adsorption of Sm on C_(60) Film

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Chinese Physics Letters 1996年第1期13卷 65-68页

作者： PAN Hai-bin xu Shi-hong xu Chang-shan LU Er-dong XIA An-dong ZHANG Guo-shang xu peng-shou ZHANG Xin-yi Changchun Institute of Physics Academia SinicaChangchun 130021 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029 Structure Research Laboratory University of Science and Technology of ChinaHefei 230026

Using photoemission spectroscopy,we have studied the adsorption of Sin on C_(60) *** tbe first stage of Sm adsorption,the C_(60) valence band shifts to the high binding energy *** maximum shift is about 0.4 *** the meantime,there appears a new structure at the upper side of the highest occupied molecule orbit(HOMO)band,which comes from the hybrid of the Sm 4f^(5) state and C_(60) HOMO *** Sm coverage increases the Sm electron is in a kind of Sm^(2+) state due to the forming of Sm cluster on the surface.

关键词： surface. film. adsorption

Studies of the Gd Overlayer on Cr by Synchrotron Radiation Photoemission

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Chinese Physics Letters 1997年第7期14卷 553-556页

作者： ZHANG Fa-pei xu peng-shou xu Shi-hong LU Er-dong YU Xiao-jiang ZHANG Xin-yi National Synchrotron Radiation Laboratory University of Science and Techology of ChinaHefei 230029

The formation of Gd/Cr interface,the growth mechanism and electronic structure of Gd over-layers were investigated by synchrotron radiation *** is shown that Gd adatoms interact with the Cr substrate weakly.A lower deposition rate of the Gd overlayer(l.0Å/min)favors the smooth growth of Gd/Cr ***,higher deposition rate(6.0Å/min)leads to the cluster growth of the Gd overlayer and the presence of a“two-peak”feature of Gd 4f *** correlate this feature with the different coordination number of surface atoms derived from cluster-induced surface roughness.

关键词： cluster roughness surface

Effect of Phase Separation Size on the Properties of Self-healing Elastomer

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Chinese Journal of Polymer Science 2024年第6期42卷 798-804页

作者： Jun xu Lei Zhu Xian-Qi Feng Cong Sui Wen-peng Zhao shou-Ke Yan School of Chemical Engineering Qingdao University of Science&TechnologyQingdao266042China College of Engineering Yanching institute of TechnologyLangfang065210China Key Laboratory of Rubber-plastics Qingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Regulation of phase structure has been recognized as one of the most effective ways to fabricate self-healing polymers with high mechanical *** mechanical properties of the resultant polymers are certainly affected by the size of separated phase ***,the study on this aspect is absence,because it can hardly exclude the influence of variation in monomer proportion required for tuning the separated phase ***,we report the first study on tuning the phase size through reversible addition-fragmentation chain transfer(RAFT)polymerization without changing the proportion of *** expected,the size of separated phase has been successfully mediated from 15 nm to 9 nm by tuning the molecular weight of the chain transfer *** is found that the mechanical strength and the self-healing efficiency of the resultant polymers increase simultaneously with the decrease of phase *** study on the formation kinetics of hydrogen bonds reveals that the decrease of phase size can facilitate the re-bonding rate of hydrogen bonds,even if the migration of polymer chains is restricted.

关键词： Self-healing polymers Phase separation Reversible addition-fragmentation chain transfer

Effect of Growth Temperature on the Band Lineup of Ge/CdTe(111) Polar Interfaces

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Chinese Physics Letters 1997年第8期14卷 609-612页

作者： BAN Da-yan FANG Rong-chuan JI xuE Jian-geng LU Er-dong xu peng-shou Department of Physics University of Science and Technology of ChinaHefei 230026 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026

By using synchrotron radiation photoelectron spectroscopy,the band lineup of Ge/CdTe(111)interfaces grown at different temperatures have been *** studies show that the valence band offset of Ge/CdTe(111)interface grown at room temperature is 0.88±0.1 eV,which agrees well with previously reported *** as for the interface grown at 280℃,an obvious reduction of valence band offsets is observed and attributed to sthe effect of different interface dipole.

关键词： value. interface valence

In-situ powder mixing for laser-based directed energy deposition of functionally graded materials

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Advances in Manufacturing 2024年第1期12卷 150-166页

作者： Ji-peng Chen shou-Chun Xie He Huang School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Nanjing Huirui Photoelectric Technology Co. LtdNanjing211121People’s Republic of China

The mixing of powders is a highly relevant field under additive manufacturing,however,it has attracted limited interest to *** in-situ mixing of various powders remains a significant *** paper proposes a new method utilizing a static mixer for the in-situ mixing of multiple powders through the laser-based directed energy deposition(DED)of functionally graded ***,a powder-mixing experimental platform was established;WC and 316L powders were selected for the mixing ***,scanning electron microscopy,energy dispersive spectroscopy,and image processing were used to visually evaluate the homogeneity and proportion of the in-situ mixed ***,powder-mixing simulations were conducted to determine the powder-mixing *** the simulations,a powder carrier gas flow field and particle mixing were ***,a WC/316L metal matrix composite sample was produced using laser-based DED to verify the application potential of the static *** was found that the static mixer could adjust the powder ratio online,and a response time of 1–2 s should be considered when adjusting the ratio of the mixed powder.A feasible approach for in-situ powder mixing for laser-based DED was demonstrated and investigated,creating the basis for functionally graded materials.

关键词： Laser Deposition Static mixer Powder mixing Functionally graded materials

A hybrid machine learning optimization algorithm for multivariable pore pressure prediction

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Petroleum Science 2024年第1期21卷 535-550页

作者： Song Deng Hao-Yu Pan Hai-Ge Wang shou-Kun xu Xiao-peng Yan Chao-Wei Li Ming-Guo peng Hao-Ping peng Lin Shi Meng Cui Fei Zhao School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou213164JiangsuChina Tubular Goods Research Institute of CNPC Beijing102249China CNPC Engineering Technology R&D Company Limited Beijing102206China

Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling *** methods for predicting pore pressure are limited when forming particular structures and *** this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore *** study collects data from three *** 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model *** this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure *** addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)*** IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training *** the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and *** achieves optimal performance on both training and test data,and the MLP model shows a high degree of *** indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure.

关键词： Pore pressure Grey wolf optimization Multilayer perceptron Effective stress Machine learning

Growth of Few-Layer Graphene on Sapphire Substrates by Directly Depositing Carbon Atoms

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Chinese Physics Letters 2011年第11期28卷 236-238页

作者： KANG Chao-Yang TANG Jun LIU Zhong-Liang LI Li-Min YAN Wen-Sheng WEI Shi-Qiang xu peng-shou National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029 School of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000

Few-layer graphene(FLG)is successfully grown on sapphire substrates by directly depositing carbon atoms at the substrate temperature of 1300℃ in a molecular beam epitaxy *** reflection high energy diffraction,Raman spectroscopy and near-edge x-ray absorption fine structure are used to characterize the sample,which confirm the formation of graphene *** mean domain size of FLG is around 29.2nm and the layer number is about 2–*** results demonstrate that the grown FLG displays a turbostratic stacking structure similar to that of the FLG produced by annealing C-terminated𝛼α-SiC surface.

关键词： terminated structure layer

Bio-inspired inorganic-protein coating on Mg-based biomaterials for bioengineering applications

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Science China Materials 2024年第5期67卷 1678-1680页

作者： xuwen peng Haolan xu Department of Chemistry Engineering Tsinghua UniversityBeijing100084China Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaT6G 1H9Canada Future Industries Institute UniSA STEMUniversity of South AustraliaMawson Lakes CampusAdelaideSouth Australia5095Australia

Developing smart and advanced functional materials inspired by the unparalleled complexity and efficiency of biological tissues has received much attention across various *** alloys,particularly pure magnesium,have emerged as notable candidates in orthopedics and dentistry due to their exceptional biocompatibility,degradability,and ability to promote bone regeneration[1].However,the highly reactive chemical nature of magnesium and its rapid degradation upon exposure to water.

关键词： coating alloys magnesium

Phase-field lattice-Boltzmann study on fully coupled thermal-solute-convection dendrite growth of Al-Cu alloy

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China Foundry 2024年第2期21卷 125-136页

作者： Yin-qi Qiu Meng-wu Wu xun-peng Qin shou-mei Xiong Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Dendrite growth is a complex liquid-solid phase transition process involving multiple physical factors.A phase-field lattice-Boltzmann method was developed to simulate the two-and three-dimension dendrite growth of Al-Cu *** effect of fully coupled thermal-solute-convection interaction on the dendrite growth was investigated by incorporating a parallel-adaptive mesh refinement algorithm into the numerical *** accurately reproducing the latent heat release,solute diffusion and convective transport behaviors at the liquidsolid interface,the interaction mechanism among thermal-solute-convection transport as well as their coupling effects on the dendrite growth dynamics were *** simulation results show that the release of latent heat slows down the dendrite growth rate,and both natural and forced convection disrupt the symmetrical growth of *** combination makes the growth of dendrites more complex,capturing important physical aspects such as recalescence,dendrite tip splitting,dendrite tilting,dendrite remelting,and solute plume in the simulation *** on the robustness and powerful ability of the numerical model,the formation mechanisms of these physical aspects were revealed.

关键词： simulation phase field dendrite growth thermal-solute-convection interaction