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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 507-511页

作者： Xinxin Fu Yu Kang Pengfei Li department of Automation University of Science and Technology of China State Key Laboratory of Fire Science Department of AutomationInstitute of Advanced TechnologyUniversity of Science and Technology of China Key Laboratory of Technology in GeoSpatial Information Processing and application System Chinese Academy of Sciences IEEE

In this paper,we studied the approximate sampleddata observer design for a class of stochastic nonlinear ***-Maruyama approximation was investigated in this paper because it is the basis of other higher precision numerical methods,and it preserves important structures of the nonlinear ***,the form of Euler-Maruyama model is simple and easy to be *** results provide a reference for sampled-data observer design method for such stochastic nonlinear systems,and may be useful to many practical control applications,such as tracking control in mechanical *** the effectiveness of the approach is demonstrated by a simulation example.

关键词： Approximation model exponentially bounded sampled-data observer stochastic nonlinear

Facile synthesis of accordion-like porous carbon from waste PET bottles-based MIL-53(Al)and its application for high-performance Zn-ion capacitor

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Green Energy & Environment 2024年第7期9卷 1138-1150页

作者： Jiaxin Li Shuai Zhang Yumeng Hua Yichao Lin Xin Wen Ewa Mijowska Tao Tang Xuecheng Chen Rodney S.Ruoff Faculty of Chemical Technology and Engineering West Pomeranian University of TechnologyPiastow Ave.4271-065SzczecinPoland Key State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Safety Engineering China University of Mining and TechnologyXuzhou221116China Institute of advanced Electrical Materials Qingdao University of Science and TechnologyQingdao266042China Institute for Basic Science Center for Multiple Dimensional Carbon Materials Ulsan44919Republic of Korea department of Chemistry Ulsan National Institute of Science and Technology(UNIST)Ulsan44919Republic of Korea department of Materials Science and Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan44919Republic of Korea School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan44919Republic of Korea

It is of great scientific and economic value to recycle waste poly(ethylene terephthalate)(PET)into high-value PET-based metal organic frameworks(MOFs)and further convert it into porous carbon for green energy storage *** the present study,a facile and costeffective hydrothermal process was developed to direct recycle waste PET bottles into MIL-53(Al)with a 100% conversation,then the MOFderived porous carbon was assembled into electrodes for high-performance *** results indicated that the as-synthesized carbon exhibited high SSA of 1712 m^(2)g^(-1)and unique accordion-like structure with hierarchical *** to these advantageous characters,the assembled three-electrode supercapacitor displayed high specific capacitances of 391 F g^(-1)at the current density of 0.5 A g^(-1)and good rate capability of 73.6% capacitance retention at 20 A g^(-1)in 6 mol L^(-1)KOH ***,the assembled zinc ion capacitor still revealed outstanding capacitance of 335 F g^(-1)at 0.1 A g^(-1),excellent cycling stability of 92.2% capacitance retention after 10000 cycles and ultra-high energy density of 150.3 Wh kg^(-1)at power density of 90 W kg^(-1)in 3 mol L^(-1)ZnSO_(4)*** is believed that the current work provides a facile and effective strategy to recycle PET waste into high-valuable MOF,and further expands the applications of MOF-derived carbons for high-performance energy storage devices,so it is conducive to both pollution alleviation and sustainable economic development.

关键词： PET Recycling Porous carbon Supercapacitor Energy storage

Improvement of Magnetic Field on Tribological Properties of Lubricating Oils with Zinc Butyloctyldithiophosphate

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China Petroleum Processing & Petrochemical Technology 2016年第4期18卷 92-98页

作者： Jiang Zeqi Fang Jianhua Chen Boshui Wu Jiang Wang Jiu Zheng Zhe department of Military Oil application & Management Engineering Logistical Engineering University

Tribological properties of 150 SN mineral oil and the oils doped with different contents of zinc butyloctyldithiophosphate(T202) under magnetic field or non-magnetic field were evaluated on a four-ball tribotester by applying an external magnetic field around the friction region. Moreover, the morphology and the tribochemical characteristics of worn surfaces were examined by a scanning electron microscope(SEM) and an X-ray photoelectron spectrometer(XPS). Then the lubrication mechanisms were discussed. The tribological test results indicated that the wear scar diameters(WSDs) of steel balls lubricated by the T202-containing lubricating oils and the friction coefficients of the corresponding oil under magnetic field were smaller than those without magnetic affection. The worn surface lubricated with the T202-formulated oils in a magnetic field was smoother than that obtained under the normal condition. Furthermore, the results of XPS analysis indicated that tribochemical films on the surfaces lubricated with T202-doped oils were mainly composed of compounds such as FeSO_4, FeS and ZnS. The atomic concentrations of oxygen, sulfur, iron, zinc and phosphorus species identified in T202 under magnetic field were higher than those without magnetic impact. It can be inferred that the improved anti-wear and friction-reducing ability of T202-doped oils was attributed to the promoted tribochemical reactions and the modification of the worn surfaces induced by magnetic field.

关键词： magnetic field zinc butyloctyldithiophosphate improvement lubrication

Pyrolysis Characteristics and Kinetics of Methyl Oleate Based on TG-FTIR Method

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China Petroleum Processing & Petrochemical Technology 2015年第2期17卷 17-25页

作者： Wang Xuechun Fang Jianhua Chen Boshui Wang Jiu Wu Jiang department of Military Oil application & Administration Engineering Logistical Engineering University

The thermal decomposition characteristics of methyl oleate were preliminarily investigated under nitrogen atmo-sphere by a thermogravimetric analyzer when the ester was heated at a heating rate of 10℃/min from room temperature to 600℃. Furthermore, the pyrolytic and kinetic characteristics of methyl oleate were intensively studied at different heating rates. The gaseous species obtained during thermal decomposition were also identiifed by the TG-FTIR coupling analysis. The results showed that the pyrolysis of methyl oleate proceeded in three stages, viz. the drying stage, the main pyrolysis stage and the residual pyrolysis stage. The initial decomposition temperature, the maximum weight loss temperature, the peak decomposition temperature and the rate of maximum weight loss of methyl oleate increased with the increasing heating rates. Gaseous CO, CO2 and H2O were the typical decomposition products from pyrolysis of methyl oleate. In addition, a kinetic model for thermal decomposition of methyl oleate was built up based on the experimental results using the Coats-Redfern integral method and the multiplelinear regression method. The activation energy, the preexponential factor, the reaction order and the kinetic equation for thermal decomposition of methyl oleate were obtained. Comparison of the experimental data with the calculated ones and analysis of statistical errors of pyrolysis ratios demonstrated that the kinetic model was reliable for studying the pyrolysis of methyl oleate. Finally, the kinetic compensation effect between the preexponential factors and the activation energy in the pyrolysis of methyl oleate was also conifrmed.

关键词： methyl oleate pyrolysis kinetics thermogravimetric analysis biodiesel

Topochemical polymerization of hydrogen-bonded organic framework for supporting ultrafine palladium nanoparticles

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Science China Chemistry 2023年第7期66卷 2019-2027页

作者： Xu Ding Bin Han Baoqiu Yu Hailong Wang Jianzhuang Jiang Beijing advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline MaterialsDepartment of Chemistry and Chemical EngineeringSchool of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Topochemical polymerization of molecular crystals into porous materials is of significance due to their promising applications in the field of adsorption and catalysis,yet rarely reported due to the synthesis ***,a hydrogen-bonded organic framework(HOF-45)has been fabricated by the crystallization of a cage-like building block containing three alkynyl *** exhibits almost mesoporous structure demonstrated by single crystal X-ray diffraction ***-driven topochemical polymerization of HOF-45 with ethanedithiol covalently links alkynyl groups in HOF-45,generating a hydrogen-bond and covalentbond cross-linked material(HOF-45C).In contrast to HOF-45,cross-linked HOF-45C retains the crystalline nature and displays improved solution resistence according to the powder X-ray diffraction *** particular,HOF-45C is able to support the growth of ultrafine palladium nanoparticles with the average size of ca.1.9 nm for rapidly promoting the degradation of nitrophenol,methyl orange,and congo red with the help of NaBH_(4)as well as Suzuki-Miyaura coupling *** work inputs a new idea on the HOFs application in preparing covalent-linked porous organic materials.

关键词： hydrogen-bonded organic frameworks topochemical polymerization palladium nanoparticles nitrophenol degradation organic dyes degradation Suzuki-Miyaura coupling reaction

Data-driven diagnosis of high temperature PEM fuel cells based on the electrochemical impedance spectroscopy: Robustness improvement and evaluation

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Journal of Energy Chemistry 2024年第9期96卷 544-558页

作者： Dan Yu Xingjun Li Samuel Simon Araya Simon Lennart Sahlin Vincenzo Liso department of Energy Aalborg UniversityAalborg 9220Denmark Walker department of Mechanical Engineering The University of Texas at AustinAustinTX 78712USA Materials Research and Technology Development Luxembourg Institute of Science and Technology(LIST)4422 BelvauxLuxembourg

Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a critical and challenging task in real application. To enhance the robustness of diagnosis and achieve a more thorough evaluation of diagnostic performance, a robust diagnostic procedure based on electrochemical impedance spectroscopy (EIS) and a new method for evaluation of the diagnosis robustness was proposed and investigated in this work. To improve the diagnosis robustness: (1) the degradation mechanism of different faults in the high temperature PEM fuel cell was first analyzed via the distribution of relaxation time of EIS to determine the equivalent circuit model (ECM) with better interpretability, simplicity and accuracy;(2) the feature extraction was implemented on the identified parameters of the ECM and extra attention was paid to distinguishing between the long-term normal degradation and other faults;(3) a Siamese Network was adopted to get features with higher robustness in a new embedding. The diagnosis was conducted using 6 classic classification algorithms—support vector machine (SVM), K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), and Naive Bayes employing a dataset comprising a total of 1935 collected EIS. To evaluate the robustness of trained models: (1) different levels of errors were added to the features for performance evaluation;(2) a robustness coefficient (Roubust_C) was defined for a quantified and explicit evaluation of the diagnosis robustness. The diagnostic models employing the proposed feature extraction method can not only achieve the higher performance of around 100% but also higher robustness for diagnosis models. Despite the initial performance being similar, the KNN demonstrated a superior robustness after feature selection and re-embedding by triplet-loss method, which sug

关键词： PEM fuel cell Data-driven diagnosis Robustness improvement and evaluation Electrochemical impedance spectroscopy

Peridynamic Modeling of Brittle Fracture in Mindlin-Reissner Shell Theory

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Computer Modeling in Engineering & Sciences 2022年第5期131卷 715-746页

作者： Sai Li Xin Lai Lisheng Liu department of Engineering Structure and Mechanics Wuhan University of TechnologyWuhan430070China Hubei Key Laboratory of Theory and application of advanced Materials Mechanics Wuhan University of TechnologyWuhan430070China State Key Laboratory of advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

In this work,wemodeled the brittle fracture of shell structure in the framework of Peridynamics Mindlin-Reissener shell theory,in which the shell is described by material points in themean-plane with its drilling rotation neglected in kinematic *** improve the numerical accuracy,the stress-point method is utilized to eliminate the numerical instability induced by the zero-energy mode and *** crack surface is represented explicitly by stress points,and a novel general crack criterion is proposed based on *** of the critical stretch used in common peridynamic solid,it is convenient to describe thematerial failure by using the classic constitutive model in continuum *** this work,a concise crack simulation algorithm is also provided to describe the crack path and its development,in order to simulate the brittle fracture of the shell *** examples are presented to validate and demonstrate our proposed *** reveal that our model has good accuracy and capability to represent crack propagation and branch spontaneously.

关键词： Peridynamic brittle fracture Reissner-Mindlin shell theory

Enhancing Direct Electrochemical CO2 Electrolysis by Introducing A-Site Deficiency for the Dual-Phase Pr（Ca）Fe（Ni）O3-δ Cathode

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Energy & Environmental Materials 2024年第5期7卷 210-218页

作者： Wanhua Wang Haixia Li Ka-Young Park Taehee Lee Dong Ding Fanglin Chen department of Mechanical Engineering University of South Carolina Energy & Environmental Science and Technology Idaho National Laboratory

High-temperature CO2electrolysis via solid oxide electrolysis cells (CO2-SOECs) has drawn special attention due to the high energy convention efficiency,fast electrode kinetics,and great potential in carbon ***,the development of cathode materials with high catalytic activity and chemical stability for pure CO2electrolysis is still a great *** this work,A-site cation deficient dual-phase material,namely(Pr0.4Ca0.6)xFe0.8Ni0.2O3-δ（PCFN,x=1,0.95,and 0.9）,has been designed as the fuel electrode for a pure CO2-SOEC,which presents superior electrochemical *** all these compositions,(Pr0.4Ca0.6)0.95Fe0.8Ni0.2O3-δ（PCFN95） exhibited the lowest polarization resistance of 0.458Ωcm2at open-circuit voltage and 800℃.The application of PCFN95 as the cathode in a single cell yields an impressive electrolysis current density of 1.76 A cm-2at 1.5 V and 800℃,which is76%higher than that of single cells with stoichiometric Pr0.4Ca0.6Fe0.8Ni0.2O3-δ（PCFN100） *** effects of A-site deficiency on materials'phase structure and physicochemical properties are also systematically *** an enhancement in electrochemical performance is attributed to the promotion of effective CO2adsorption,as well as the improved electrode kinetics resulting from the A-site deficiency.

关键词： A-site deficiency cathode material CO2 adsorption direct CO2 electrolysis solid oxide electrolysis cells

Performance comparison of machine learning algorithms for maximum displacement prediction in soldier pile wall excavation

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Underground Space 2024年第3期16卷 301-313页

作者： Danial Sheini Dashtgoli Mohammad Hossein Dehnad Seyed Ahmad Mobinipour Michela Giustiniani department of Mathematics Informaticsand GeosciencesUniversity of TriesteTrieste 34127Italy National Institute of Oceanography and Applied Geophysics-OGS Borgo Grotta Gigante 42/CTriesteSgonico 34010Italy department of Civil Engineering University of QomQom ***Iran

One of the common excavation methods in the construction of urban infrastructures as well as water and wastewater facilities is the excavation through soldier pile *** maximum lateral displacement of pile wall is one of the important variables in controlling the stability of the excavation and its adjacent ***,the application of machine learning methods is widely used in engineering sciences due to its low cost and high speed of *** paper utilized three intelligent machine learning algorithms based on the excavation method through soldier pile walls,namely eXtreme gradient boosting(XGBoost),least square support vector regressor(LS-SVR),and random forest(RF),to predict maximum lateral displacement of pile *** results showed that the implemented XGBoost model performed excellently and could make predictions for maximum lateral displacement of pile walls with the mean absolute error of 0.1669,the highest coefficient of determination 0.9991,and the lowest root mean square error *** the LS-SVR,and RF models were less accurate than the XGBoost model,they provided good prediction results of maximum lateral displacement of pile walls for numerical ***,a sensitivity analysis was performed to determine the most effective parameters in the XGBoost *** analysis showed that soil elastic modulus and excavation height had a strong influence on of maximum lateral displacement of pile wall prediction.

关键词： Soldier pile wall Lateral displacements XGBoost Machine learning Artificial intelligence

VISCOPLASTIC COLLAPSE OF SHARP-NOTCHED CIRCULAR TUBES UNDER CYCLIC BENDING

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Acta Mechanica Solida Sinica 2013年第6期26卷 629-641页

作者： Kuo-Long Lee Chien-Min Hsu Wen-Fung Pan department of Computer application Engineering Far East University department of Interior Design Tung Fang Design University department of Engineering Science National Cheng Kung University

This study discusses the experimental result of the viscoplastic response and col- lapse of sharp-notched 316L stainless steel tubes with different notched depths subjected to cyclic bending. The tube bending machine and curvature-ovalization measurement apparatus were used for conducting the symmetric curvature-controlled cyclic bending. To highlight the viscoplastic behavior, three different curvature-rates, 0.0035, 0.035 and 0.35 m-1s-1, were controlled. Ob- servations of a certain curvature-rate reveal that five almost parallel lines corresponding to five different notch-depth （0.2, 0.4, 0.6, 0.8 and 1.0 mm） tubes were presented in the experimental relationship between the cyclic controlled curvature and the number of cycles needed to pro- duce buckling on a log-log scale. However, the slopes for the three different curvature-rates are different. An empirical formulation was proposed to simulate the aforementioned relationship. When comparing with the experimental findings, the simulation was in good agreement with the experimental data.

关键词： viscoplastic collapse sharp-notched circular tube cyclic bending curvature-rate ovalization