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Journal of Bionic Engineering 2022年第1期19卷 155-166页

作者： Jingdan Li Qian liang wen Qin Jing Ma School of Material Science and Engineering Taiyuan University of TechnologyTaiyuan030024China

High wear resistance,low cytotoxicity and excellent antibacterial properties are the basis for osseointegration of implant ***(PEEK)has been considered as a potential implant material due to its excellent biocompatibility,natural radiolucency and mechanical *** this work,to improve the wear resistance,cytotoxicity and antibacterial properties of PEEK,carbon fiber(CFR)and Black Phosphorus(BP)were used to synergistically modify PEEK by two methods,deposition of BP coating on CFR-PEEK and BP/CFR-PEEK coating on Ti6Al4V(TC4)through electrostatic *** CFR and BP synergistically modified PEEK,the friction coefficient of BP coating on CFR-PEEK and BP/CFR-PEEK coating were 0.14±0.01 and 0.09±0.02,*** wear volume of BP coating on CFR-PEEK(30.54±1.32)was higher than that of BP/CFR-PEEK coating(9.46±1.32),which indicated that BP/CFR-PEEK coating showed high wear *** difference in wear resistance may be caused by the fact that BP was not easily oxidized in BP/CFR-PEEK *** addition,BP coating on CFR-PEEK and BP/CFR-PEEK coating showed no obvious cytotoxicity to L929 cell and presented excellent antibacterial efficiency(up to 94.5%±2.8%and 96.0%±3.8%,respectively)against Staphylococcus aureus(***).It was concluded that BP/CFR-PEEK coating exhibited high wear resistance,low cytotoxicity and excellent antibacterial properties against ***,which might provide a foundation for osseointegration of implants.

关键词： Surface deposition Electrostatic spraying Wear resistance Cytotoxicity Antibacterial properties

A review of Fe_3O_4 thin films:Synthesis,modification and applications

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Journal of Materials Science & Technology 2018年第8期34卷 1259-1272页

作者： Xiaoyi Wang Yulong liao Dainan Zhang Tianlong wen Zhiyong Zhong Center for Applied Chemistry University of Electronic Science and Technology of China State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of China

Magnetite （Fe3O4） has been used for thousands of years as one of the important magnetic materials. The rapid developments of thin film technology in the past few decades attract the attention of material scientists on the fabrication of magnetite thin films. In this article, we present an overview of recent progress on Fe3O4 thin films. The widely used preparation methods are surveyed, and the effect of sub- strates is discussed. Specifically the modified Fe3O4 thin films exhibit excellent electrical and magnetic properties compared with the pure films. It is noteworthy that modified Fe3O4 thin films can be put into two categories：（1） doped films, where foreign metal ions substitute iron ions at A or B sites： and （2） hybrid films, where magnetite phases are mixed with other materials. Notably, Fe3O4 thin films show great potentials in many applications such as sensors and batteries. It is expected that the investigations of Fe3O4 thin films will give us some breakthroughs in materials science and technology.

关键词： Fe3O4 Thin film Preparation method Modified film Material science

Deployment dynamics for flexible deployable primary mirror of space telescope with paraboloidal and laminated structure by using absolute node coordinate method

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Chinese Journal of Aeronautics 2021年第4期34卷 306-319页

作者： Bindi YOU Dong liang Xiangjie YU Xiaolei wen School of Naval Architecture and Ocean Engineering Harbin Institute of TechnologyWeihai 264209China

A nonlinear dynamic modeling method for primary mirror of Flower-like Deployable Space Telescope(F-DST)undergoing large deployment motion is proposed in this *** ensure pointing accuracy and attitude stability of the paraboloidal primary mirror,the mirror is discretized into equal thickness shell elements by considering shell *** the material nonlinear constitutive relation of flexible mirror is acquired using Absolute Nodal Coordinate Formulation(ANCF).Furthermore,the primary mirror of F-DST can be regarded as a clustered multi-body system,and its dynamic equations of elastic deformation and deployment motion are established by virtual work ***,the deployment motion of primary mirror by different driving conditions are simulated,the results show that the vibrations of mirrors that driven by elastic hinge device are more than that driven by servo *** addition,single sub-mirror deployment process will perturb the pointing accuracy of primary mirror,and the multiple sub-mirrors simultaneously deploying will seriously affect all the sub-mirrors surface accuracy because of the coupling ***,there are theoretical value and practical significance for the controlling surface accuracy and attitude accuracy of space telescope.

关键词： Deployable space telescope Deployment dynamics Flexible deformation Laminated mirror Paraboloidal structure

Characterization of dissolved organic matter fractions from Lake Hongfeng, Southwestern China Plateau

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Journal of Environmental Sciences 2009年第5期21卷 581-588页

作者： WANG Liying WU Fengchang ZHANG Runyu LI wen liao Haiqing State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China State Environmental Protection Key Laboratory for Lake Pollution Control Research Center of Lake Eco-Environment Chinese Research Academy of Environmental Sciences Beifing 100012 China

With XAD-series and ion exchange resins, dissolved organic matter （DOM） from Lake Hongfeng in Southwestern China Plateau was isolated into 6 fractions, i.e., humic acid （HA）, fulvic acid （FA）, hydrophobic neutrals （HON）, hydrophilic acids （HIA）, hydrophilic bases （HIB） and hydrophilic neutrals （HIN）. Those fractions were characterized by high performance size exclusion chromatography, fluorescence spectroscopy and UV absorbance. Among the 6 fractions, FA was predominant and accounted for 51% of the total DOM. The weight-average （Mw） and number-averaged （Mn） molecular weight of these fractions ranged from 1688 to 2355 Da and from 1338 to 1928 Da, respectively. A strong correlation was observed between specific UV absorbance at 280 nm, E2/E3 （absorbance at 250 nm to 365 nm）, and the molecular weight for DOM fractions. UV-Vis fulvic-like fluorescence peaks were found in all fractions. Proteinlike fluorescence peaks existed in HON may indicate that microbial activity was severely in Lake Hongfeng. There was a significant relationship between fluorescence intensities and specific UV absorbance at 254 nm for those DOM fractions, suggesting their similar luminescence characteristics. The values of fluorescence index （f450/500） indicated that hydrophobic fractions may derive from terrestrial sources, and the hydrophilic fractions from microbial and terrestrial origins. Those results suggest that there were inter-relationships between molecular weight, fluorescence and absorbance characteristics, and also subtle consistencies between the hydrophilic and hydrophobic properties and the sources for these 6 fractions from Lake Hongfeng.

关键词： dissolved organic matter fractionation molecular weight UV absorbance fluorescence spectroscopy

Synthesis and Properties of a Heteronuclear Ag(Ⅰ)/Ni(Ⅱ) Complex

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Chemical Research in Chinese Universities 2006年第3期22卷 283-286页

作者： WANG Jiang-yun GU wen WANG wen-zhen LIU Xin liao Dai-zheng Department of Chemistry Nankai University Tianjin 300071 P. R. China

A complex, Ni （en）2Ag3 （CN） s （ en =ethylenediamine）, was obtained through the reaction of [ Ag （ CN ）2 ]^- units with Ni II -diamine cation C Ni （en）2]^2＋, and the structure was determined by single crystal X-ray diffraction. It is indicated that the complex has a 3D architecture through the silver-silver interactions and the bridging eyano groups. This complex displays interesting luminescent properties caused by argentophilieity at room temperature in solid state.

关键词： Single crystal X-ray diffraction Silver-silver interaction Argentophilieity luminescent property

LCCFS: a lightweight distributed file system for cloud computing without journaling and metadata services

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Science China(Information Sciences) 2019年第7期62卷 142-155页

作者： Li WANG Jingling XUE Xiangke liao Yunchuan wen Min CHEN School of Computer Science and Technology National University of Defense Technology School of Computer Science and Engineering University of New South Wales

The major usage of a file system integrated with a cloud computing platform is to provide the storage for VM(virtual machine) instances. Distributed file systems, especially those implemented on top of object storage have many potential advantages over traditional local file systems for VM instance storage. In this paper, we make an investigation in the requirements imposed on a file system in cloud computing scenario,and claim that the implementation of a file system for VM instance storage could be reasonably simplified. We demonstrate that on top of an object storage with simple object-granularity transaction support, a lightweight distributed file system, which requires neither journaling nor dedicated metadata services, can be developed for cloud computing. We have implemented such a distributed file system, called LCCFS(lightweight cloud computing file system), based on the RADOS(reliable autonomic distributed object storage) object *** experimental results show that for the main workloads in cloud computing, LCCFS achieves almost the same or slightly higher performance than CephFS(ceph filesystem), another published distributed file system based on RADOS. Compared to CephFS, LCCFS has only one tenth of its LOCs(lines of code). This theoretical simplicity makes it easy to implement LCCFS correctly and stably by avoiding the sheer design and implementation complexity behind CephFS, thereby making LCCFS a promising candidate in the cloud computing production environment.

关键词： cloud computing distributed file system journaling metadata service garbage collection

The axisymmetric torsional contact problem of a functionally graded piezoelectric coated half-space

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Acta Mechanica Sinica 2017年第2期33卷 406-414页

作者： Jie Su liao-liang Ke Yue-Sheng Wang Yang Xiang Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China School of Computing Engineering and MathematicsWestern Sydney University Penrith South NSW 2751 Australia Centre for Infrastructure Engineering Western Sydney University Penrith South NSW 2751 Australia

In this article, we study the axisymmetric torsional contact problem of a half-space coated with functionally graded piezoelectric material (FGPM) and subjected to a rigid circular punch. It is found that, along the thickness direction, the electromechanical properties of FGPMs change exponentially. We apply the Hankel integral transform technique and reduce the problem to a singular integral equation, and then numerically determine the unknown contact stress and electric displacement at the contact surface. The results show that the surface contact stress, surface azimuthal displacement, surface electric displacement, and inner electromechanical field are obviously dependent on the gradient index of the FGPM coating. It is found that we can adjust the gradient index of the FGPM coating to modify the distributions of the electric displacement and contact stress.

关键词： Axisymmetric torsional contact Singular integral equation Functionally graded piezoelectric materials (FGPMs)

Distributed user pairing and effective computation offloading in aerial edge networks

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Chinese Journal of Aeronautics 2024年第4期37卷 378-390页

作者： Wei liang Shuhui wen Lixin LI Jingjing CUI School of Electronics and Information Northwestern Polytechnical UniversityXi’an CN710072China The State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an CN710126China School of Electronics and Computer Science University of SouthamptonSouthampton SO167NSUK

Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access ***,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial *** this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial ***,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation *** the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy *** the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user ***,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of ***,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual ***,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low ***,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.

关键词： Aerial edge computing Binary offloading Cognitive radio Hybrid offloading Resource management

Study on Unloading Creep Characteristics of the Soil and Application of the Stress-Dependent Creep Model in Suction Caisson Foundation

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China Ocean Engineering 2022年第1期36卷 123-132页

作者： ZHU wen-bo DAI Guo-liang GONG Wei-ming ZHAO Xue-liang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Southeast UniversityNanjing 211189China School of Civil Engineering Southeast UniversityNanjing 211189China

As the anchoring foundation of the tension leg platform(TLP),suction caisson foundation is subjected to the long-term vertical pullout *** there are few studies on the mechanism of the unloading creep of soft clay and long-term uplift bearing capacity of suction caisson *** address this problem,unloading creep tests of soft clay were carried out to analyze the strain development with time under different confining *** test results show that the creep curve rapidly develops in the early stage and tends to stabilize in the later *** unloading deviator stress is higher,the unloading creep deformation is greater and the soft clay has typical nonlinear creep ***,by introducing the creep model and considering the influence of the deviator stress,the stress-dependent Merchant model is proposed to describe the unloading creep of soft ***,the stress-dependent Merchant model is extended to a three-dimension constitutive model,and a finite element subroutine is developed to establish a finite element analysis method for analyzing the long-term uplift capacity of suction caisson foundations and validated with the long-term uplift bearing capacity results of caisson model.

关键词： suction caisson foundation soft clay unloading creep creep model finite element

Hybrid vibration isolation optimization of a flexible manipulator based on neural network agent model

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Chinese Journal of Aeronautics 2024年第5期37卷 482-505页

作者： Yongxin ZHANG liang LI Dingguo ZHANG Wei-Hsin liao Xian GUO School of Science Nanjing University of Science and TechnologyNanjing 210094China Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina

Segmented Active Constrained Layer Damping(SACLD)is an intelligent vibration-damping structure,which could be applied to the sectors of aviation,aerospace,and transportation engineering to reduce the vibration of flexible ***,machine learning technology is widely used in the engineering field because of its efficient multi-objective *** dynamic simulation of a rotational segmental flexible manipulator system is presented,in which enhanced active constrained layer damping is carried out,and the neural network model of Genetic Algorithm-Back Propagation(GA-BP)algorithm is *** suppression and structural optimization of the SACLD manipulator model are studied based on vibration mode and damping *** modal responses of the SACLD manipulator model at rest and rotation are *** addition,the four model indices are optimized using the GA-BP neural network:axial incision size,axial incision position,circumferential incision size,and circumferential incision ***,the best model for vibration suppression is obtained.

关键词： Machine learning Vibration suppression Flexible manipulator Segmented active constrained layer damping Structural optimization