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Inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1370页

作者： Lele REN Wei ZHANG Yufei ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell,in cases of 1:2 inter-well internal resonance and primary *** transverse foundation excitation is applied to the fixed end of the structure,and the other end is in a free *** first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control *** four-dimensional averaged equations are derived in both polar and rectangular coordinate *** from the obtained frequency-amplitude and force-amplitude response curves,a detailed analysis is conducted to examine the impacts of excitation amplitude,damping coefficient,and tuning parameter on the nonlinear internal resonance characteristics of the *** nonlinear softening characteristic is exhibited in the upper stable-state,while the lower stable-state demonstrates the softening and linearity *** simulation is carried out using the fourth-order Runge-Kutta method,and a series of nonlinear response curves are *** the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： bistable composite laminated cantilever shell inter-well internal resonance primary resonance chaotic dynamic snap-through complex nonlinear vibration

Basic solutions of multiple parallel symmetric mode-III cracks in functionally graded piezoelectric/piezomagnetic material plane

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Applied Mathematics and Mechanics(English Edition) 2013年第10期34卷 1201-1224页

作者：泮世东周振功吴林志 Center for composite Materials and structures Harbin Institute of Technology

The Schmidt method is adopted to investigate the fracture problem of multiple parallel symmetric and permeable finite length mode-III cracks in a functionally graded piezoelectric/piezomagnetic material plane. This problem is formulated into dual integral equations, in which the unknown variables are the displacement jumps across the crack surfaces. In order to obtain the dual integral equations, the displacement jumps across the crack surfaces are directly expanded as a series of Jacobi polynomials. The results show that the stress, the electric displacement, and the magnetic flux intensity factors of cracks depend on the crack length, the functionally graded parameter, and the distance among the multiple parallel cracks. The crack shielding effect is also obviously presented in a functionally graded piezoelectric/piezomagnetic material plane with mul- tiple parallel symmetric mode-III cracks.

关键词： functionally graded piezoelectric/piezomagnetic material multiple parallel symmetric crack crack shielding effect solid mechanics

The nonlocal theory solution of a Mode-I crack in functionally graded materials

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Science China(Technological Sciences) 2009年第4期52卷 1101-1111页

作者： LIANG Jun Center for composite Materials and structures, Harbin Institute of Technology, Harbin 150001, China Center for composite Materials and structures Harbin Institute of Technology

The behavior of a Mode-I finite crack in functionally graded materials is investigated using the non-local theory. To make the analysis tractable, it is assumed that the shear modulus varies exponentially with coordinate vertical to the crack. The problem in this paper can be solved through the Fourier transform with the help of two pairs of dual integral equations, in which the unknown variables are jumps of dis- placements across crack surfaces. To solve dual integral equations, the jumps of displacements across crack surfaces are directly expanded in a series of Jacobi polynomials. Unlike the classical elasticity solutions, it is found that no stress singularities are present at crack tips. The non-local elastic solu- tions yield a finite stress at crack tips, thus allowing us to use the maximum stress as a fracture crite- rion. Numerical examples are provided to show the effects of the crack length, the parameter describ- ing the functionally graded materials, the lattice parameter of materials and the materials constants upon the stress fields near crack tips.

关键词： crack functionally graded materials the non-local theory mechanics of solids

Interconnected microstructure and flexural behavior of Ti_(2)C-Ti composites with superior Young’s modulus

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2088-2101页

作者： Fengbo Sun Rui Zhang Fanchao Meng Shuai Wang Lujun Huang Lin Geng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Waikato Centre for Advanced Materials and Manufacturing School of EngineeringUniversity of WaikatoHamilton 3240New Zealand State Key Laboratory of Precision Welding&Joining of Materials and structures Harbin Institute of TechnologyHarbin 150001China

To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman *** to the results,the in-situ reaction yielded an interconnected microstructure composed of Ti_(2)C particles when the Ti_(2)C content reached 50vol%.With widths of 10 and 230 nm,the intraparticle Ti lamellae in the prepared composite exhibited a bimodal size distribution due to precipitation and the unreacted Ti phase within the grown Ti_(2)C *** composites with interconnected microstructure attained superior properties,including E of 174.3 GPa and ultimate flexural strength of 1014 *** with that of pure Ti,the E of the composite was increased by 55% due to the high Ti_(2)C content and interconnected *** outstanding strength resulted from the strong interfacial bonding,load-bearing capacity of interconnected Ti_(2)C particles,and bimodal intraparticle Ti lamellae,which minimized the average crack driving *** flexural tests revealed preferential crack initiation along the{001}cleavage plane and grain boundary of Ti_(2)C in the region with the highest tensile *** addition,the propagation can be efficiently inhibited by interparticle Ti grains,which prevented the brittle fracture of the composites.

关键词： titanium matrix composites titanium carbide interface Young’s modulus flexural behavior

Influence of modeling approaches and structural parameters on impact resistance of the human porous cranium

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Acta Mechanica Sinica 2021年第6期37卷 910-928,I0001页

作者： Qianqian Wu Jian Xiong Center for composite Materials and structures Harbin Institute of TechnologyHarbin150001China

Failure mechanism and impact resistance of a human porous cranium are studied in detail by means of theoretical and numerical *** is hypothesized that pore distribution of a cranium directly affects cranial energy absorption,and a stretched beam model and a real beam model are taken as the example for the ***,for the purpose of comparison with numerical results,a theoretical model is also proposed for the prediction of residual velocity and contact force of the impactor for an impacted *** with the real beam model,the stretched beam model containing through-thickness pores is easily deformed under the impact,thereby buffering well the external impact *** energy absorption efficiency of both the stretched beam model and real beam model is concerned with the threshold velocity for penetration which is directly related to the size of the structural damage ***,there is good agreement between numerical and theoretical *** addition,the effect of structural geometric parameters(shape and size of the impactor)on the impact resistance of the skull bone is theoretically *** study provides reference for the evaluation of the energy absorption and failure mechanism of the skull under impact loads.

关键词： Skull porous structure Impact resistance Modeling approach Theoretical prediction Influence of structural parameters

Review on regulation of MnS in non-qquenched and tempered steel

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Journal of Iron and steel Research International 2024年第4期31卷 779-789页

作者： Guo-xing Qiu Qing Du Feng Lu De-jun Miao Yong-kun Yang Xiao-ming Li School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina Laigang Technique Center Shandong Iron and Steel Group Co.Ltd.Jinan 271104ShandongChina

An overview of the current research status and control methods of MnS in non-quenched and tempered steel was *** a low-melting plastic inclusion,the morphology and distribution of MnS were influenced by various production ***,control of MnS is a systematic problem that must be integrated into the entire production *** on the production process,the factors affecting the morphology and distribution of MnS in steel were *** effects of oxygen activity,manganese,sulfur,and some alloys on MnS inclusion precipitation were summarized,mainly including MnS modification treatment and oxygen-sulfide composite precipitation *** is believed that MnS precipitates during the solidification process of steel,and controlling the solidification cooling rate could effectively regulate the size and morphology of MnS,avoiding the precipitation of ***,by changing the deformation rate,deformation amount,deformation temperature during the hot deformation process,and heating time and temperature during heat treatment,the distribution and morphology of MnS could be *** the fine control of the above process parameters,the number of II-MnS in steel could be effectively reduced,and their morphology could be improved,thereby enhancing the performance of non-quenched and tempered steel and promoting its wider ***,applying laboratory research results to industrial production is an important direction for future research efforts in this field.

关键词： MnS Non-quenched and tempered steel Control technology Process parameter Morphology Distribution

Reliability-based life-cycle cost seismic design optimization of coastal bridge piers with nonuniform corrosion using different materials

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 209-225页

作者： Wu Xiangtong Yuan Wenting Guo Anxin Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China Key Lab of structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Institute of Transportation Inner Mongolia UniversityHohhot 010070China

Reinforcement corrosion is the main cause of performance deterioration of reinforced concrete(RC)*** research has been performed to investigate the life-cycle cost(LCC)of coastal bridge piers with nonuniform corrosion using different *** this study,a reliability-based design optimization(RBDO)procedure is improved for the design of coastal bridge piers using six groups of commonly used materials,i.e.,normal performance concrete(NPC)with black steel(BS)rebar,high strength steel(HSS)rebar,epoxy coated(EC)rebar,and stainless steel(SS)rebar(named NPC-BS,NPC-HSS,NPC-EC,and NPC-SS,respectively),NPC with BS with silane soakage on the pier surface(named NPC-Silane),and high-performance concrete(HPC)with BS rebar(named HPC-BS).First,the RBDO procedure is improved for the design optimization of coastal bridge piers,and a bridge is selected to illustrate the ***,reliability analysis of the pier designed with each group of materials is carried out to obtain the time-dependent reliability in terms of the ultimate and serviceability ***,the repair time of the pier is predicted based on the time-dependent reliability ***,the time-dependent LCCs for the pier are obtained for the selection of the optimal design.

关键词： reliability-based design optimization(RBDO) life-cycle cost(LCC) nonuniform corrosion coastal bridge pier repair

High-entropy oxide-supported platinum nanoparticles for efficient hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1537-1546页

作者： Ming-Yu Fan Jia-Jun Wang Jun Zhao Hong Zhang Tian-Yi Ma Xiao-Peng Han Wen-Bin Hu School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Key Laboratory of Advanced Ceramics and Machining TechnologyTianjin UniversityTianjin300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China School of Science RMIT UniversityMelbourneVIC3000Australia

High-entropy oxides(HEOs)are a new class of single-phase structures with unique electronic and catalytic properties;therefore,it is worthwhile to explore their applications in *** this study,a Pt/(FeCoNiCrAl)_(3)O_(4)nanohybrid using HEO as a support was developed as an efficient catalyst for the hydrogen evolution reaction(HER).Pt/(FeCoNiCrAl)_(3)O_(4)exhibited high HER activity with a low overpotential of 22 mV at10 mA·cm^(-2),outperforming other binary,ternary,and quaternary *** HER activity of Pt/(FeCoNiCrAl)_(3)O_(4)was higher than that of a commercial Pt/C with a significantly lower Pt *** catalyst exhibited good activity and long-term stability(60 h)in an electrolytic water-splitting *** good activity can be attributed to the fact that the introduction of Pt effectively facilitates electronic interactions between Pt and the *** addition,the HEO substrate was more favorable for dispersing Pt particles,optimizing the electrochemical specific surface area,and significantly reducing the charge resistance of the *** study extends the application of HEOs in electrocatalysis and demonstrates the promising prospects of HEOs as supports for electrocatalysts.

关键词： High-entropy oxides Hydrogen evolution reaction Nanohybrid Water electrolysis

Shape Memory Epoxy Resin and Its composites:From Materials to Applications

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Research 2022年第2期2022卷 345-369页

作者： Lan Luo Fenghua Zhang Jinsong Leng Centre for composite Materials and structures Harbin Institute of Technology(HIT)Harbin 150080China

Shape memory polymers(SMPs)have historically attracted attention for their unique stimulation-responsive and variable stifness and have made notable progress in acrospace,civil industry,and other *** particular,epoxy resin(EP)has great potential due to its excellent mechanical properties,fatigue resistance,and radiation ***,we focus on the molecular design and network construction of shape memory epoxy resins(SMEPs)to provide opportunities for performance and functional *** and high-performance SMEPs are introduced in detail,including multiple SMEPs,two-way SMEPs,outstanding toughness,and termperature ***,emerging applications of SMEP's and their composites in aerospace,four-dimensional printing,and self-healing are *** on this,we point out the challenges ahead and how SMEPs can integrate performance and versatility to meet the needs of technological development.

关键词： composites printing resins