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Journal of Materials Science & Technology 2021年第15期74卷 136-142页

作者： Qingkai Shen xiangdong kong Xizhang Chen College of Mechanical and Electrical Engineering Wenzhou UniversityWenzhou325000China

Additive manufacturing is a very promising manufacturing method widely used in various *** this study,for the first time,a new type of combined cable wire(CCW)with multi-element composition has been designed and developed for arc additive manufacturing(AAM)of non-equiatomic Al-Co-Cr-FeNi high-entropy *** composed of 7 filaments and 5 elements has the advantages of high deposition efficiency,self-rotation of welding arc and energy saving *** HEA walls were fabricated under pure argon gas using cold metal transfer *** observations of the developed HEA reveal(i)BCC and FCC phases,(ii)Good bonding between layers and(iii)defect-free *** developed alloy exhibits high compression strength(~2.8 GPa)coupled with high plastic strain(~42%)values(possess both strength and ductility).It has been identified that by varying the heat input via torch travel speed,the microstructure and mechanical properties of the HEA can be *** this feasibility study,it has been proved that the innovative CCW method can be used to manufacture HEAs with ***,the study highlights the advantage of the rapid cooling involved in the CCW-AAM process which gives rise to superior mechanical properties.

关键词： Combined cable wire Arc additive manufacturing High-entropy alloy Microstructure Mechanical properties

Electrodeposited highly-oriented bismuth microparticles for efficient CO_(2)electroreduction into formate

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Nano Research 2022年第12期15卷 10078-10083页

作者： Chen Lin Yan Liu xiangdong kong Zhigang Geng Jie Zeng University of Science and Technology of China Hefei230026China

Bi is one of the most fascinating catalysts for the formation of HCOO-towards CO_(2)***,we developed electrodeposited angular-shaped Bi microparticles(Bi MP)with exposed surfaces of{003}and{101}planes as efficient catalyst for the electroreduction of CO_(2)into HCOO-.During CO_(2)electroreduction,Bi MP achieved a Faraday efficiency(FE)for HCOO-of higher than 95%over a wide range of applied potential from-0.6 to-1.1 V versus reversible hydrogen electrode(***),whereas the FE for HCOO-of Bi nanoflakes(Bi NF)with exposed surfaces of{104}and{110}planes was around 70%.At-1.1 V ***,the partial current density for HCOO-of Bi MP was-271.7 mA·cm-2,1.56 times as high as that of Bi *** to kinetic analysis and mechanistic study,highly-oriented surface of Bi MP not only facilitated Faradaic process and accelerated reaction kinetics via enhancing the CO_(2)activation,but also restrained competing hydrogen evolution reaction,thus boosting catalytic performance of the electroreduction of CO_(2)into HCOO-.

关键词： electrodeposited Bi formate product highly-oriented bismuth surface CO_(2)electroreduction

Nonlinear Mathematical Modeling and Sensitivity Analysis of Hydraulic Drive Unit

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 999-1011页

作者： kong xiangdong YU Bin QUAN Lingxiao BA Kaixian WU Liujie National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan University Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University School of Mechanical Engineering Yanshan University

The previous sensitivity analysis researches are not accurate enough and also have the limited reference value, because those mathematical models are relatively simple and the change of the load and the initial displacement changes of the piston are ignored, even experiment verification is not conducted. Therefore, in view of deficiencies above, a nonlinear mathematical model is established in this paper, including dynamic characteristics of servo valve, nonlinear characteristics of pressure-flow, initial displacement of servo cylinder piston and friction nonlinearity. The transfer function block diagram is built for the hydraulic drive unit closed loop position control, as well as the state equations. Through deriving the time-varying coefficient items matrix and time-varying free items matrix of sensitivity equations respectively, the expression of sensitivity equations based on the nonlinear mathematical model are obtained. According to structure parameters of hydraulic drive unit, working parameters, fluid transmission characteristics and measured friction-velocity curves, the simulation analysis of hydraulic drive unit is completed on the MATLAB/Simulink simulation platform with the displacement step 2 mm, 5 mm and 10 mm, respectively. The simulation results indicate that the developed nonlinear mathematical model is sufficient by comparing the characteristic curves of experimental step response and simulation step response under different constant load. Then, the sensitivity function time-history curves of seventeen parameters are obtained, basing on each state vector time-history curve of step response characteristic. The maximum value of displacement variation percentage and the sum of displacement variation absolute values in the sampling time are both taken as sensitivity indexes. The sensitivity indexes values above are calculated and shown visually in histograms under different working conditions, and change rules are analyzed. Then the sensitivity index

关键词： nonlinear mathematical model hydraulic drive unit valve-controlled symmetrical cylinder sensitivity analysis sensitivity index

Study on co-simulation model of forging manipulator based on virtual prototyping

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High Technology Letters 2016年第2期22卷 128-134页

作者：翟富刚 Zhu Hanyin Wu Qilei kong xiangdong School of Mechanical Engineering Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science(Yanshan University) Ministry of Education of China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University

Based on the characteristics of integrated virtual prototype technology, the mechanical system sub-model, the hydraulic system sub-model and the control system sub-model of a forging manipula- tor system have been built using a variety of software, and a forging manipulator mtrltidisciplinary co- simulation model has been also built using a method of simulation models interface. Then the simu- lation and experiment are finished, and the result of the experiment is in good agreement with the re- sult of the simulation. It shows that the co-simulation model established can simulate accurately pa- rameter changes in real time during the moving of the forging manipulator such as displacement, ve- locity and pressure flow, which is of important significance for the optimized design of the forging manipulator system to establish the models.

关键词： forging manipulator virtual prototype co-simulation control characteristics

Enhance the activity of multi-carbon products for Cu via P doping towards CO_(2) reduction

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Science China Chemistry 2021年第7期64卷 1096-1102页

作者： xiangdong kong Cheng Wang Han Zheng Zhigang Geng Jun Bao Jie Zeng Hefei National Laboratory for Physical Sciences at the Microscale Key La boratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of SciencesKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesDepartment of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

Electronic structure engineering is a powerful method to tailor the behavior of adsorbed intermediates on the surface of catalysts,thus regulating catalytic activity towards CO_(2)***,we prepared a series of P-doped Cu catalysts for CO_(2)electroreduction into multi-carbon(C_(2+))products by regulating the surface electronic structure of *** introduction of P could stabilize the surface Cu^(δ+)species,enhancing the activity for C_(2+)products via adjusting the adsorbed strength of the CO intermediates(~*CO).When the molar ratio of P to Cu was 8.3%,the catalyst exhibited a Faradaic efficiency of 64%for C_(2+)products,which was 1.9 times as high as that(33%)for Cu catalysts at the applied current density of 210 m A cm^(-2).Notably,at the applied current density of 300 mA cm^(-2),the P-doped Cu catalyst with the molar ratio of P to Cu of 8.3%exhibited the highest partial current density for C_(2+)products of 176 mA cm^(-2),whereas the partial current density for C_(2+)products over the Cu catalyst was only 84 mA cm^(-2).Mechanistic studies revealed that modulating the molar ratios of P to Cu regulated the adsorbed strength of~*CO.A moderate adsorbed strength of *CO induced by appropriate P doping was responsible for the facilitated C–C coupling process.

关键词： P-doped Cu catalysts C^(2+)products ~*CO adsorption CO_(2)electroreduction

Polyethyleneimine-modified calcium carbonate nanoparticles for p53 gene delivery

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Regenerative Biomaterials 2016年第1期3卷 57-63页

作者： Cen Chen Huafeng Han Wei Yang Xiaoyuan Ren xiangdong kong Bio-X Center College of Life SciencesZhejiang Sci-Tech UniversityHangzhou 310018China Institute of Biomaterials and Marine Biological Resources College of Life SciencesZhejiang Sci-Tech UniversityHangzhou 310018China

In this study,calcium carbonate(CaCO3)nanoparticles with spherical structure were regulated by arginine and successfully synthesized via a facile co-precipitation *** average particle size of as-prepared CaCO3 was about 900 *** properties of nanostructured CaCO3 particles were characterized by scanning electron microscope,Fourier transform infrared spectroscopy,Xray diffraction and size *** modified with polyethyleneimine(PEI),the ability of PEICaCO3 nanoparticles to carry GFP-marked p53 gene(pEGFP-C1-p53)into cancer cells to express P53 protein were ***,the cytotoxicity,transfection efficiency,cells growth inhibition and the ability to induce apoptosis by expressed P53 protein were conducted to evaluate the performances of PEI-CaCO3 *** results show that prepared PEI-CaCO3 nanoparticles had good biocompatibility and low cytotoxicity in a certain concentration ***-CaCO3 effectively transfected pEGFP-C1 gene into epithelial-like cancer *** with the expression of GFP-P53 fusion protein,pEGFP-C1-p53-gene-loaded PEI-CaCO3 particles significantly reduced the proliferation of cancer *** findings indicate that our PEI-modified CaCO3 nanoparticles are potential to be successfully used as carriers for gene therapy.

关键词： calcium carbonate gene therapy nanoparticles polyethyleneimine p53

Force Control Compensation Method with Variable Load Stiffness and Damping of the Hydraulic Drive Unit Force Control System

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 454-464页

作者： kong xiangdong BA Kaixian YU Bin CAO Yuan ZHU Qixin ZHAO Hualong National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan University School of Mechanical Engineering Yanshan University State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University

Each joint of hydraulic drive quadruped robot is driven by the hydraulic drive unit（HDU）, and the contacting between the robot foot end and the ground is complex and variable, which increases the difficulty of force control inevitably. In the recent years, although many scholars researched some control methods such as disturbance rejection control, parameter self-adaptive control, impedance control and so on, to improve the force control performance of HDU, the robustness of the force control still needs improving. Therefore, how to simulate the complex and variable load characteristics of the environment structure and how to ensure HDU having excellent force control performance with the complex and variable load characteristics are key issues to be solved in this paper. The force control system mathematic model of HDU is established by the mechanism modeling method, and the theoretical models of a novel force control compensation method and a load characteristics simulation method under different environment structures are derived, considering the dynamic characteristics of the load stiffness and the load damping under different environment structures. Then, simulation effects of the variable load stiffness and load damping under the step and sinusoidal load force are analyzed experimentally on the HDU force control performance test platform, which provides the foundation for the force control compensation experiment research. In addition, the optimized PID control parameters are designed to make the HDU have better force control performance with suitable load stiffness and load damping, under which the force control compensation method is introduced, and the robustness of the force control system with several constant load characteristics and the variable load characteristics respectively are comparatively analyzed by experiment. The research results indicate that if the load characteristics are known, the force control compensation method presented in this paper

关键词： quadruped robot force control system hydraulic drive unit force control compensation method variable load stiffness and damping simulation

DEVELOPMENT OF DC MILL——WITH WORK ROLLS DEVIATED AND CROSSED

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Chinese Journal of Mechanical Engineering 1998年第4期11卷 47-52页

作者： Liu Yuli Jin Xiaoguang Lian Jiachuang kong xiangdong (Yanshan University) Yanshan Univ China

A new type of 4 high strip mill is developed, in which gauge and shape are combinatively controlled by work roll deviating and crossing. The neewly developed 300 mm 4 h mill and its control system are introduced. Both static and dynamic experiments as well as theoretical study are carried out to verify the advantages and the combined shape and gauge control function of this new mill.

关键词： DC mill Shape Control

Applications of in-situ spectroscopic techniques towards CO_(2)electroreduction

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Science China Chemistry 2024年第12期67卷 3925-3933页

作者： Haoyu Zhang Chaoyue Gu Minghui Fan Zhi Zhao xiangdong kong Zhigang Geng Hefei National Research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei 230026China The Instruments Center for Physical Science University of Science and Technology of ChinaHefei 230026China

In-situ experimental techniques have been widely applied to uncover the dynamic evolutions of both the structure of catalysts and the interfacial property of catalysis,thus serving as the most important means to gain molecular-level insights into the reaction *** this mini review,we summarized recent progress in the applications of the interface-sensitive in-situ Raman and in-situ infrared(IR)spectroscopy towards CO_(2)***,we concentrated on two aspects to clarify the role of both in-situ Raman and in-situ IR in revealing reaction mechanisms of CO_(2)*** first one was the in-situ spectroscopy for detecting the active *** other one was the in-situ spectroscopy for capturing the reaction *** powerful guidance for the rational design of catalysts,the reaction mechanism was discussed in the specific ***,we try to predict the trends for the future development of in-situ spectroscopic techniques towards heterogeneous catalysis.

关键词： in-situ Raman in-situ IR active structure of catalysts reaction intermediates CO_(2)electroreduction

Control characteristics of D + A combined multi-pump controlled system

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High Technology Letters 2018年第3期24卷 303-312页

作者：姚静 Wang Pei Cao Xiaoming Zhang Yang kong xiangdong College of Mechanical Engineering Yanshan University The Laboratory of Heavy Machinery Fluid Power Transmission and Control in Hebei Yanshan University National and Local Joint Engineering Center for Advanced Forging Press Forming Technology and Equipment Faculty of Engineering Yanshan University

In order to solve the flow mismatch problem between pumping source output and workload demand,a novel configuration of D + A combined multi-pump controlled hydraulic system,similar to a pump-controlled system,is proposed for a large power hydraulic system in this study. This novel configuration consists of several parallel fixed displacement pumps of different sizes and proportional variable displacement pumps,which is controlled by digital signal( on/off) and analog signal respectively( D + A pumps). The system flow is divided into two parts,one is the total flow from fixed displacement pumps,and the other is the rest desired flow supplied by variable displacement pumps to smooth and improve the demand flow. First,basic design principles and evaluation indicators of the proposed system are introduced. Then,a flow state matrix of the binary-coding digital pumps( 1: 2: 4) is obtained to provide the control signals of pumps. Experimental results show that the system output flow tracks well with acceptable flow deviation,though a little lag behind input signal.

关键词： multi-pump design principles flow state matrix evaluation indicator energy saving