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Acta metallurgica Sinica(English Letters) 2000年第4期13卷 937-943页

作者： J.m. hu h.m. meng D.B. Sun S.J. Zhang J.X. Wu and D.J. Yang Beijing Corrosion and Protection Center, Open Laboratory of Corrosion, Erosion and Surface Technology, University of Science and Technology Beijing, Beijing 100083, China Beijing Univ of Science and Technology Beijing China

Service life of two different oxide anodes in phenolsulfonic acid (PSA) solution was investigated by accelerated electrolysis. The durability of Ti/IrO_2+Ta_2 O_5 anode increased by the addition of SnO_2 in the mixed oxides. The degradation mechanisms of Ti/IrO_2+ Ta_2 O_5 and Ti/IrO_2 +Ta_2 O_5 +SnO+2 anodes were different. It was shown from the observation of scanning electron microscopy (SEm) and the electroch.m.cal measurement that, the deactivation of Ti/IrO_2 + Ta_2 O_5 anode was due to the build-up of an organic film on surface. The growth of the covered film on surface was restricted by addition of SnO_2, which resulted in increasing of the service life of anodes. The over-potential for oxygen evolution on Ti/IrO_2 +Ta_2 O_5 electrode increased after doping SnO_2, and the intermediate products of PSA building-up on the surface was much.m.re rapidly oxidized. meanwhile, a certain part of the surface oxide deposit entered into the solution leading to loss of oxides, which resulted in degradation of Ti/IroO_2 + Ta_2 O_5 anode containing SnO_2 component.

关键词： metal oxide anode IrO_2 + Ta_2 O_5 IrO_2 + Ta_2 O_5 +SnO_2 phenolsulfonic acid degradation

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied math.m.tics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** h.m.lton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and h.m.genous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

Attractor for the Extensible Beam Equation with Nonlocal Weak Damping on Time–Dependent Space

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Acta math.m.tica Sinica,English Series 2024年第4期40卷 1115-1126页

作者： Chun Xiang ZhAO Feng Juan meng Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013P.R.China School of math.m.tics and Physics Jiangsu University of TechnologyChangzhou 213001P.R.China

In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at *** the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed *** results obtained essentially improve and complete some previous works.

关键词： Time-dependent attractor extensible beams equation nonlocal weak damping

Experimental study on the variation of optical remote sensing imaging characteristics of internal solitary waves with wind speed

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Journal of Oceanology and Limnology 2024年第2期42卷 408-420页

作者： Zhe ChANG Lina SUN Tengfei LIU meng ZhANG Keda LIANG Junmin meng Jing WANG School of Physics and Optoelectronic Engineering Ocean University of ChinaQingdao 266100China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

Optical remote sensing has been widely used to study internal solitary waves(ISWs).Wind speed has an important effect on ISW imaging of optical remote *** light and dark bands of ISWs cannot be observed by optical remote sensing when the wind is too *** relationship between the characteristics of ISWs bands in optical remote sensing images and the wind speed is still *** influence of wind speeds on the characteristics of the ISWs bands is investigated based on the physical simulation experiments with the wind speeds of 1.6,3.1,3.5,3.8,and 3.9 m/*** experimental results show that when the wind speed is 3.9 m/s,the ISWs bands cannot be observed in optical remote sensing images with the stratification of h_(1)∶h_(2)=7∶58,ρ_(1)∶ρ_(2)=1∶*** the wind speeds are 3.1,3.5,and 3.8 m/s,which is lower than 3.9 m/s,the ISWs bands can be obtained in the simulated optical remote sensing *** location of the band’s dark and light extremum and the band’s peak-to-peak spacing are almost not affected by wind ***-significant wind speeds can cause a greater gray difference of the light-dark *** provided a scientific basis for further understanding of ISW optical remote sensing imaging.

关键词： internal solitary wave(ISW) optical remote sensing wind speed characteristics of ISWs bands

Fuzzy-model-Based Finite Frequency Fault Detection Filtering Design for Two-Dimensional Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2099-2110页

作者： meng Wang huaicheng Yan Jianbin Qiu Wenqiang Ji Key Laboratory of Smart manufacturing in Energy Ch.m.cal Process Ministry of EducationSchool of Information Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Research Institute of Intelligent Control and Systems School of AstronauticsHarbin Institute of TechnologyHarbin 150080China School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China IEEE

This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy ***,fuzzy Lyapunov functions are constructed and the 2-D Fourier transform is exploited,based on which a finite frequency fault detection filtering design method is proposed such that a residual signal is generated with robustness to external disturbances and sensitivity to *** has been shown that the utilization of available frequency spectrum information of faults and disturbances makes the proposed filtering design method more general and less conservative compared with a conventional nonfrequency based filtering design ***,with the proposed evaluation function and its threshold,a novel mixed finite frequency h_(∞)/h_(-)fault detection algorithm is developed,based on which the fault can be immediately detected once the evaluation function exceeds the ***,it is verified with simulation studies that the proposed method is effective and less conservative than conventional non-frequency and/or common Lyapunov function based filtering design methods.

关键词： Fault diagnosis finite frequency specifications mixed h_(∞)/h_(-)performance two-dimensional nonlinear systems

CONSERVATIVE CONFORmING AND NONCONFORmING VEmS FOR FOURTh ORDER NONLINEAR SChRODINGER EQUATIONS WITh TRAPPED TERm

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Journal of Computational math.m.tics 2024年第2期42卷 454-499页

作者： meng Li Jikun Zhao Zhongchi Wang Shaochun Chen School of math.m.tics and Statistics Zhengzhou UniversityZhengzhou 450001China School of Computer Science and Engineering Beihang universityBeijing 100083China

This paper aims to construct and analyze the conforming and nonconforming virtual element methods for a class of fourth order nonlinear Schrodinger equations with trapped *** mainly consider three types of virtual elements,including h^(2) conforming virtual element,C^(0) nonconforming virtual element and morley-type nonconforming virtual *** fully discrete sch.m.s are constructed by virtue of virtual element methods in space and modified Crank-Nicolson method in *** prove the mass and energy conservation,the boundedness and the unique solvability of the fully discrete *** introducing a new type of the Ritz projection,the optimal and unconditional error estimates for the fully discrete sch.m.s are presented and ***,two numerical examples are investigated to confirm our theoretical analysis.

关键词： h^(2)conforming virtual element C^(0)nonconforming virtual element morleytype nonconforming virtual element Nonlinear Schrodinger equation Conservation Convergence

Novel synthesis of stabilized Bi1-x-yGdxDyyO1.5 solid electrolytes with enhanced conductivity for intermediate temperature solid oxide fuel cells（SOFCs）

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Journal of Rare Earths 2024年第10期42卷 1903-1911页

作者： Ahmed h.Ibrah.m.Yehia m.Abbas h.A.Ayoub marwa h.Ali mustafa Aldoori materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University ministry of higher Education and Scientific Research Aliraqia University

herein,we report the synthesis of a Dy-Gd co-doped cubic phase-stabilized Bi2O3solid electrolyte system via solid-state processing under atmospheric *** with Dy3+and Gd3+has been observed to significantly enhance the densification process during sintering for stabilization purposes,thereby improving the electrical properties of δ-Bi2O3-type *** synthesized ceramics were characterized using X-ray diffraction（XRD）,field emission scanning electron microscopy-energy dispersive X-ray spectroscopy（FESEm-EDX）,thermal gravimetry/differential thermal analysis（TG/DTA）,and the four-point probe technique（4PPT）.XRD analysis reveals that the samples Bi1-x-yGdxDyyO1.5（y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20） exhibit a stable face-centered cubic δ-phase and a mixed-phase crystallographic *** XRD analysis of the stabilized δ-phase suggests that the prepared oxides show a face-centered cubic（FCC） structure with a space group of *** micrographs reveal that the composition Bi0.90Gd0.05Dy0.05O1.5has no significant ***,an evident increase in the pore formation is observed as the amount of Gd2O3increases until it reaches 20%.This finding suggests that dense pellets are formed during the sintering process at 900-1000℃.The DTA analyses were performed to verify the phase stability,which agrees with the XRD *** electroch.m.cal performance of the synthesized Dy-Gd co-doped Bi2O3solid electrolyte system was evaluated and analyzed in detail by using the electroch.m.cal impedance spectroscopy（EIS） technique,Based on EIS and conductivity measurements,Bi0.75Gd0.20Dy0.05O1.5exhibits the lowest activation energy of 0.519 eV and the highest conductivity value of 0.398 S/cm at 627℃compared to the other samples;this composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells（SOFCs）.

关键词： Electroch.m.cal impedance spectroscopy (EIS) Fast Fourier transform (FFT) Rare earths Rietveld Solid oxide fuel cells (SOFCs) Solid-state processing

Bioinspired design of integral molded Janus silk fibroin-mXene evaporator for efficient solar vapor generation

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Nano Research 2024年第4期17卷 2824-2835页

作者： Ling-Qing Kong Zhi-Cheng Zeng Guang-Zong min Zhao-hui meng Guo-Qing meng Xiao-Xiao Guo Nai-Bo Lin Xiang-Yang Liu The higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of marine Environmental Science(mEL) College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China

Solar vapor generation is a promising sustainable technology that uses solar distillation to produce fresh water from seawater and wastewater,helping relieve global water resource ***,inspired by naturally grown integrally molded mulberry leaves with a Janus hydrophilic and hydrophobic structure,a novel,simple,and efficient integrated molding method is proposed to break through the limitations of the traditional split manufacturing strategy and realizes the integrated formation of Janus *** on the spontaneous sedimentation characteristics of mXene in silk fibroin solution and its regulation of mesoscopic structure and hydrophilicity of silk fibroin,layered structures with different compositions and hydrophilicities were obtained in one ***,ethanol and glutaraldehyde were added to construct a physical crystallization-ch.m.cal crosslinking dual stabilization structure in silk *** evaporator has the evaporation rate of 3.07 kg·m^(-2)·h^(-1) and the efficiency of 86.8%under 1 sun and maintains high evaporation performance under various extreme test conditions including vigorous washing,repeated compression,and high-intensity ultraviolet(UV)***,the evaporator performs well in practical application scenarios,its evaporation rate in the simulated Dead Sea seawater exceeds 2.13 kg·m^(-2)·h^(-1),and more than 99.9%of the salt,heavy metal ions,oil pollution,and dyes are purified.

关键词： silk fibroin mXene bioinspired integrated molding Janus structure solar vapor generation

Co-doped Ni_(3)S_(2) nanosheet array: A high-efficiency electrocatalyst for alkaline seawater oxidation

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Nano Research 2024年第3期17卷 1050-1055页

作者： meng Yue Xun he Shengjun Sun Yuntong Sun moh.m.d S.h.m.y mh.m.d Benaissa Alsamani A.m.Salih Jun Liu Xuping Sun College of Ch.m.stry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Ch.m.stry College of ScienceKing Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Department of Ch.m.cal Engineering College of EngineeringUniversity of Ha’ilP.O.Box 2440Ha’il 81441Saudi Arabia Department of Otolaryngology-head&Neck Surgery West China HospitalSichuan UniversityChengdu 610041China

Developing efficient and durable oxygen evolution reaction(OER)catalysts holds great promise for green hydrogen production via seawater electrolysis,but remains a ***,we report a Co-doped Ni_(3)S_(2) nanosheet array on Ni foam(Co-Ni_(3)S_(2)/NF)as a high-efficiency OER electrocatalyst for *** alkaline conditions,Co-Ni_(3)S_(2)/NF requires an overpotential of only 368 mV to drive 100 mA·cm^(–2),superior to Ni_(3)S_(2)/NF(385 mV).Besides,it exhibits at least 50-h continuous electrolysis.

关键词： Co doping Ni_(3)S_(2)nanosheet array oxygen evolution reaction seawater electrolysis electrocatalyst

Predicting submerged vegetation drag with a machine learning-based method

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Journal of hydrodynamics 2024年第3期36卷 534-545页

作者： meng-yang Liu hong-wu Tang Sai-yu Yuan Jing Yan College of Water Conservancy and hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of hydrologic-Cycle and hydrodynamic-System of ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(h^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array