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Effect of Heat Treatment on Structure and Magnetic Performance of Ni-Fe-P Alloy Obtained by Electroless Plating

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Chemical Research in Chinese Universities 2005年第6期21卷 718-722页

作者： wang sen-lin ZHANG Yong College of Materials Science and Engineering ChinaCollege of Information Science and Engineering Huaqiao University Quanzhou 362021 P. R.China

The electroless deposition of Ni68-Fe10.5-P21.5 alloy has been investigated. The crystallization behavior of the deposit was comparatively studied by using differential scanning calorimetry and X-ray diffractometry. The deposit transforms into a square Ni3P phase at 380. 0 ℃, then changes into a cubic FeNi3 phase at 490. 0 ℃. The microhardness, the size of the formed grains and the magnetic performance of the deposit increase with the increase of the heat treatment temperature below 500 ℃, then they decrease after this temperature. The effect of heat treatment time at 500 ℃ on the surface micromorphology, the structure and the magnetic performance of the deposit were also studied. The resuits show that with the increase of heat treatment time, the extent of crystallization of the deposit increases and the size of the formed grains becomes uniform. The results also show that the magnetic performance of the deposit under heat treatment for 40 min is maximal and then decreases with the increase of heat treatment time. The property change of the deposit is related to the crystal structure and the size of the formed grains of the deposit.

关键词： Electroless plating Ni-Fe-P alloy Heat treatment Magnetic performance

Event-triggered robust guaranteed cost control for two-dimensional nonlinear discrete-time systems

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1243-1251页

作者： wang sen BU Xuhui LIANG Jiaqi School of Electrical Engineering and Automation Henan Polytechnic University

An event-triggered scheme is proposed to solve the problems of robust guaranteed cost control for a class of two-dimensional(2-D)discrete-time ***,an eventtriggered scheme is proposed for 2-D discrete-time systems with parameter uncertainties and sector ***,according to the Lyapunov functional method,the sufficient conditions for the existence of event-triggered robust guaranteed cost controller for 2-D discrete-time systems with parameter uncertainties and sector nonlinearities are ***,based on the sufficient conditions and the linear matrix inequality(LMI)technique,the problem of designing event-triggered robust guaranteed cost controller is transformed into a feasible solution problem of ***,a numerical example is given to demonstrate that,under the proposed event-triggered robust guaranteed cost control,the closed-loop system is asymptotically stable and fewer communication resources are occupied.

关键词： event-triggered robust guaranteed cost control two dimensional(2-D)nonlinear system networked control system.

A robust extraction algorithm for biomedical signals from noisy mixtures

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Frontiers of Computer Science 2011年第4期5卷 387-394页

作者： Yongjian ZHAO Boqiang LIU sen wang School of Control Science and Engineering Shandong University Jinan 250061 China School of Information Engineering Shandong University at Weihai Weihai 264209 China Kodak Research Laboratories Eastman Kodak Company Rochester NY 14620 USA

Blind source extraction （BSE） is widely used to solve signal mixture problems where there are only a few desired signals. To improve signal extraction performance and expand its application, we develop an adaptive BSE algorithm with an additive noise model. We first present an improved normalized kurtosis as an objective function, which caters for the effect of noise. By combining the objective function and Lagrange multiplier method, we further propose a robust algorithm that can extract the desired signal as the first output signal. Simulations on both synthetic and real biomedical signals demonstrate that such combination improves the extrac- tion performance and has better robustness to the estimation error of normalized kurtosis value in the presence of noise.

关键词： blind source extraction (BSE) normalizedkurtosis objective function biomedical signal Lagrangemultiplier method

Room-temperature fast assembly of 3D macroscopically porous graphene frameworks for binder-free compact supercapacitors with high gravimetric and volumetric capacitances

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Journal of Energy Chemistry 2021年第10期30卷 23-28,I0002页

作者： sen wang Xiao wang Chenglin Sun Zhong-Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian 116023LiaoningChina Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian 116023LiaoningChina University of Chinese Academy of Sciences Shijingshan District19 A Yuquan RdBeijing 100049China

Synthesis and applications of three-dimensional(3 D)porous graphene frameworks(GFs)have attracted extensive interest owing to their intriguing advantages of high specific surface area,enriched porosity,excellent electrical conductivity,exceptional compressibility and ***,it is still challenging for economically viable,fast and scalable assembly of 3 D GFs at ***,we reported a one-step scalable strategy for fast self-assembly of graphene oxide into 3 D macroscopically porous GFs,with assistance of polyoxometalates(POM)as functional cross-linker and hydrazine hydrate as reductant at *** resulting 3 D interconnected macroporous POM-GFs uniformly decorated with ultrasmall POM nanoclusters were directly processed into binder-/additive-free film compact electrodes(1.68 g cm^(-3))with highly aligned,layer-stacked structure and electrically conductivity(622 S m-1)for high-performance supercapacitors,showing an impressive gravimetric capacitance of205 F g-1,volumetric capacitance of 334 F cm^(-3) at 1 mV s^(-1),and remarkable cycling stability with capacitance retention of 83%after 10,000 cycles,outperforming the most reported ***,the solid-state supercapacitors offered excellent gravimetric capacitance of 157 F g-1 exceptionally volumetric capacitance of 115 F cm^(-3) at 2 mV s^(-1) based on single electrode,and volumetric energy density of2.6 mWh cm^(-3).Therefore,this work will open novel opportunities to room-temperature fast assembly of 3 D porous graphene architectures for high-energy-density supercapacitors.

关键词： Graphene frameworks Room-temperature fast assembly Supercapacitors

Mechanical Properties Study of Reinforced Thermoplastic Pipes Under A Tensile Load

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China Ocean Engineering 2020年第6期34卷 806-816页

作者： wang Yang-yang LOU Min TONG Bing wang sen School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao 266580China Hoisting Machinery Business Division Xuzhou Construction Machinery Group(XCMG)Xuzhou 221000China Weihai Nacheon Pipeline Co. Ltd.Weihai 264400China

This paper presents a study on the tensile properties of reinforced thermoplastic pipes(RTPs). A mechanical model of RTPs with an arbitrary number of reinforced layers under tensile action is constructed by combining the constitutive relationship of elastoplastic materials with the continuous displacement condition. On this basis, the effects of various parameters such as the winding angle, the number of structurally reinforced layers, and the inner polyethylene(PE) liner thickness on the tensile properties of the RTPs were analyzed, and a tensile test was carried out for validation. The results showed that the winding angle of the structurally reinforced layers was the main factor affecting an RTP's tensile performance— decreases in the winding angle significantly improved its tensile ability,especially the longitudinal strength. With ±45° as the demarcation point, the winding angle smaller than ±45° will result in higher strength in longitudinal direction, and the lifting effect on RTP's mechanical properties of the increasing number of reinforcement layers was better than that of the increasing thickness of the lining layer;when the winding angle was larger than ±45°, the opposite results were obtained. The fibre load was more sensitive to the winding angle than the PE load.

关键词： reinforced thermoplastic pipes tensile properties winding angle polyethylene

Flutter analysis of rotating beams with elastic restraints

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Applied Mathematics and Mechanics(English Edition) 2022年第5期43卷 761-776页

作者： Lüsen wang Zhu SU Lifeng wang State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The aeroelastic stability of rotating beams with elastic restraints is *** coupled bending-torsional Euler-Bernoulli beam and Timoshenko beam models are adopted for the structural *** Greenberg aerodynamic model is used to describe the unsteady aerodynamic *** additional centrifugal stiffness effect and elastic boundary conditions are considered in the form of potential energy.A modified Fourier series method is used to assume the displacement field function and solve the governing *** convergence and accuracy of the method are verified by comparison of numerical ***,the flutter analysis of the rotating beam structure is carried out,and the critical rotational velocity of the flutter is *** results show that the elastic boundary reduces the critical flutter velocity of the rotating beam,and the elastic range of torsional spring is larger than the elastic range of linear spring.

关键词： rotating beam modified Fourier series method elastic restraint flutter

Electroless plating of Ni-Zn(Fe)-P alloy on carbon steel sheets

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 157-161页

作者： wang sen-lin WU Hui-huang College of Materials Science and Engineering Huaqiao University Quanzhou 362021 China State Key Laboratory for Physical Chemistry of Solid Surface Department of ChemistryXiamen University Xiamen 361005 China State Key Laboratory for Physical Chemistry of Solid Surface Department of ChemistryXiamen University Xiamen 361005 China

The autocatalytic deposition of Ni-Zn(Fe)-P alloys were carried out on carbon steel sheets from bath containing nickel sulfate, zinc sulfate, sodium hypophosphite, sodium citrate and boric acid. The effects of pH and mole ratio of NiSO4/ZnSO4 on the deposition rate and the composition of deposit were studied. It is found that the presence of zinc sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the mole fraction of zinc in the deposits never reaches high value, which is less than 18.0%. The structure and surface morphology of Ni-Zn(Fe)-P coatings were charactered by XRD and SEM. The alloys plated at all conditions consist of amorphous phase coexisting with a crystalline cubic Ni phase. The surface morphology of coating is dependent on the deposition parameters.

关键词： electroless plating nickel zinc

Identification of carbonates with high positive carbon isotope excursion from the Liaohe Group in the northeastern North China Craton and implications for the Lomagundi-Jatuli Event

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Science China Earth Sciences 2024年第9期67卷 2824-2844页

作者： Hongyu wang Shuanhong ZHANG sen wang Linghao KONG Yue ZHAO Qiqi ZHANG sen GAO Guohui HU Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Paleomagnetism and Tectonic Reconstruction Ministry of Natural ResourcesBeijing 100081China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100037China School of Earth Science and Mineral Resources China University of GeosciencesBeijing 100083China

The Great Oxidation Event(GOE)during the early Paleoproterozoic represents the first significant buildup in Earth’s atmospheric oxygen and resulted in a series of significant changes in the Earth’s surface *** them is the 2.22(or 2.33)–2.06 Ga Lomagundi-Jatuli Event(LJE),which is globally,the largest magnitude and longest duration,marine carbonate positive carbon isotope excursion(δ^(13)C_(V-PDB)>10‰)*** event has attracted the attention of scholars all over the ***,except for a high positive carbon isotope excursion(δ^(13)C_(V-PDB)>10‰)recently identified from marine carbonate rocks within the Daposhan Formation in the lower Fanhe Group(or the Sanchazi Group)in the Longgang Block in the northeast North China Craton(NCC),Paleoproterozoic carbonates in the NCC are characterized by a low-amplitude positive carbon isotope excursion(δ^(13)C_(V-PDB)10‰)of marine carbonate rocks occurred at about 2.15 *** co

关键词： Lomagundi-Jatuli Event(LJE) Great Oxidation Event(GOE) Carbon-oxygen isotopes Liaohe Group Marine carbonate Jiao-Liao-Ji Belt North China Craton

Dynamic State Estimation of Power Systems with Uncertainties Based on Robust Adaptive Unscented Kalman Filter

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1065-1074页

作者： Dongchen Hou Yonghui Sun Jianxi wang Linchuang Zhang sen wang College of Energy and Electrical Engineering Hohai UniversityNanjing210098China

In this paper,a robust adaptive unscented Kalman filter(RAUKF)is developed to mitigate the unfavorable effects derived from uncertainties in noise and in the *** address these issues,a robust M-estimator is first utilized to update the measurement noise ***,to deal with the effects of model parameter errors while considering the computational complexity and real-time requirements of dynamic state estimation,an adaptive update method is *** proposed method is integrated with spherical simplex unscented transformation technology,and then a novel derivative-free filter is proposed to dynamically track the states of the power system against ***,the effectiveness and robustness of the proposed method are demonstrated through extensive simulation experiments on an IEEE 39-bus test *** with other methods,the proposed method can capture the dynamic characteristics of a synchronous generator more reliably.

关键词： Dynamic state estimation Kalman filter synchronous generator unscented transformation robust estimation