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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1017-1032页

作者： Demin ZHAO Jianlin LIU c.q.wu Department of Mechanics College of Pipeline and Civil Engineering China University of Petroleum Department of Mechanical and Manufacturing Engineering University of Manitoba

The parametric excited vibration of a pipe under thermal loading may occur because the fluid is often transported heatedly. The effects of thermal loading on the pipe stability and local bifurcations have rarely been studied. The stability and the local bifurcations of the lateral parametric resonance of the pipe induced by the pulsating fluid velocity and the thermal loading are studied. A mathematical model for a simply supported pipe is developed according to the Hamilton principle. Two partial differential equations describing the lateral and longitudinal vibration are obtained. The singularity theory is utilized to anMyze the stability and the bifurcation of the system solutions. The transition sets and the bifurcation diagrams are obtained both in the unfolding parameter space and the physical parameter space, which can reveal the relationship between the thermal field parameter and the dynamic behaviors of the pipe. The frequency response and the relationship between the critical thermal rate and the pulsating fluid velocity are obtained. The numerical results demonstrate the accuracy of the single-mode expansion of the solution and the stability and local bifurcation analyses. It also confirms the existence of the chaos. The presented work can provide valuable information for the design of the pipeline and the controllers to prevent the structural instability.

关键词： thermal load parameter excited local bifurcation,unfolding parameterspace physical parameter space

A Verifiable Trust-Based cP-ABE Access control Scheme for cloud-Assisted Renewable Energy Systems

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computers, Materials & continua 2025年第1期82卷 1211-1232页

作者： Jiyu Zhang Kehe wu Ruomeng Yan Zheng Tian Yizhen Sun Yuxi wu Yaogong Guo Department of control and computer Engineering North China Electric Power UniversityBeijing102206China State Grid Information&communication company of Hunan Electric Power corporation Changsha410118China State Grid Hunan Electric Power corporation chenzhou Power Supply Branch Chenzhou423000China

Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intelligent processing on edge servers(ES).However,securely distributing encrypted data stored in the cloud to terminals that meet decryption requirements has become a prominent research ***,managing attributes,including addition,deletion,and modification,is a crucial issue in the access control scheme for *** address these security concerns,a trust-based ciphertext-policy attribute-based encryption(cP-ABE)device access control scheme is proposed for RES(TB-cP-ABE).This scheme effectivelymanages the distribution and control of encrypted data on the cloud through robust attribute key *** introducing trust management mechanisms and outsourced decryption technology,the ES system can effectively assess and manage the trust worthiness of terminal devices,ensuring that only trusted devices can participate in data exchange and access sensitive ***,the ES system dynamically evaluates trust scores to set decryption trust thresholds,thereby regulating device data access permissions and enhancing the system’s *** validate the security of the proposed TB-cP-ABE against chosen plaintext attacks,a comprehensive formal security analysis is conducted using the widely accepted random oraclemodel under the decisional q-Bilinear Diffie-Hellman Exponent(q-BDHE)***,comparative analysis with other schemes demonstrates that the TB-cP-ABE scheme cuts energy/communication costs by 43%,and scaleswell with rising terminals,maintaining average latency below 50ms,ensuring real-time service *** proposed scheme not only provides newinsights for the secure management of RES but also lays a foundation for future secure energy solutions.

关键词： Access control renewable energy systems(RES) ciphertext-policy attribute-based encryption(cP-ABE) security

Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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Journal of Energy chemistry 2025年第1期100卷 710-720页

作者： Wenxuan chen Xiu-qing qiao Guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian wu Tao wu Dong-Sheng Li college of Materials and chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges Laboratory college of chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-cdS/Mo2c@c heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the cdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-cdS （c-cdS） and hexagonal-cdS （h-cdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-cdS phase junction to realize gradient charge ***,the photothermal effect of Mo2c@c helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-cMc photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of cdS by constructing plasmonic tandem heterogeneous junctions.

关键词： cadmium sulfide

Estimation of chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 49-64页

作者： WANG Xin SHEN Dejian TAO Sijie LIU Ruixin wu Shengxing college of civil and Transportation Engineering Hohai UniversityNanjing 210098China

This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(c3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated c3S *** results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.

关键词： tricalcium silicate simulation method chloride diffusion coefficient pore solution

Measurement and Prediction of Insertion Force for the Mosquito Fascicle Penetrating into Human Skin

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Journal of Bionic Engineering 2009年第2期6卷 143-152页

作者： X q Kong c W wu State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsDalian University of Technology

Mosquitoes are exceptional in their ability to pierce into human skin with a natural ultimate painless microneedle, named fascicle. Here the structure of the Aedes albopictus mosquito fascicle is obtained using a Scanning Electron Microscope (SEM), and the whole process of the fascicle inserting into human skin is observed using a high-speed video imaging technique. Direct measurements of the insertion force for mosquito fascicle to penetrate into human skin are reported. Results show that the mosquito uses a very low force (average 18 μN) to penetrate into the skin. This force is at least three orders of magnitude smaller than the reported lowest insertion force for an artificial microneedle with an ultra sharp tip to insert into the human skin. In order to understand the piercing mechanism of mosquito fascicle tip into human multilayer skin tissue, a numerical simulation is conducted to analyze the insertion process using a nonlinear finite element method. A good agreement occurs between the numerical results and the experimental measurements.

关键词： biomimetic microneedle mosquito fascicle mechanics penetration

Tuning the interfacial reaction environment via pH-dependent and induced ions to understand c–N bonds coupling performance in NO3- integrated cO2 reduction to carbon and nitrogen compounds over dual cu-based N-doped carbon catalyst

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Journal of Energy chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou chen Shen Zhenghao wu Xingying Lan Yi Xiao college of carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAc）,particularly copper （cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert cO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves c–c and c–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of cu-based catalysts for the N-integrated cO2reduction reaction （cO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a cu2-based N-doped carbon (cu2N6c10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of cO2,the formation of a solvation electric layer by anions （F-,cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and ca2+) leads to electron transfer towards the cu *** process significantly accelerates the reduction of *** results reveal that*cO intermediates play a pivotal role in N-integrated ***,the cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for c–N coupling to *** findings reveal that through the process of a condensation reaction between*cO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*cO2to*ccO at dual cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and ca2+were ***,the mechanisms of c–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： condensation reactions

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： Yan Zhao qiang Yuan Liting Yang Guisheng Liang Yifeng cheng Limin wu chunfu Lin Renchao che college of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10c and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1c and 25//−10//60℃)and outstanding rate performance(10 to 0.5c capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

Experimental Observing Damage Evolution in cement Pastes Exposed to External Sulfate Attack by in situ X-ray computed Tomography

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 164-170页

作者： wu Min cAO Kailei XIAO Weirong YU Zetai cAO Jierong DING qingjun LI Jinhui china Railway construction corporation Harbour and channel Engineering Bureau Group co. LTDZhuhai 519000China con-struction Headquarters of Zhoushan Liuheng Bridge Phase II Project Zhoushan 316000China china Railway construction Bridge En-gineering Bureau Group co. LTDTianjin 300000China State Key Laboratory of Silicate Material for Architecture(wuhan University of Technology) Wuhan 430070China college of Materials Science and Engineering Wuhan Textile UniversityWuhan 430200China

The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray cT)was used,i e,the tomography system of Zeiss Xradia 510 *** results indicate that X-cT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack *** addition,the c3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate *** damage of ordinary Portland cement(OPc)pastes subjected to sulfate attack with high c3A content are severe,while the damage of sulfate resistant Portland cement(SRPc)pastes is much smaller than that of OPc ***,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution.

关键词： concrete external sulfate attack damage evolution situ X-ray computed tomography

Interference Suppression and Jitter Elimination Ability-Based Adaption Tracking Guidance for Robotic Fishes

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IEEE/cAA Journal of Automatica Sinica 2025年第1期 126-137页

作者： Dongfang Li Jie Huang Rob Law Xin Xu Limin Zhu Edmond q.wu IEEE the School of Electrical Engineering and Automation Fuzhou University the Key Laboratory of System control and Information Processing Ministry of Education the School of Electrical Engineering and Automation Fuzhou University 5G+Industrial Internet Institute Fuzhou University the University of Macau the college of Mechatronics and Automation National University of Defense Technology the School of Mechanical Engineering Shanghai Jiao Tong University the Department of computer Science and Engineering Shanghai Jiao Tong University

This work presents an adaptive tracking guidance method for robotic fishes. The scheme enables robots to suppress external interference and eliminate motion jitter. An adaptive integral surge line-of-sight guidance rule is designed to eliminate dynamics interference and sideslip issues. Limited-time yaw and surge speed observers are reported to fit disturbance variables in the model. The approximation values can compensate for the system's control input and improve the robots' tracking ***, this work develops a terminal sliding mode controller and third-order differential processor to determine the rotational torque and reduce the robots' run jitter. Then, Lyapunov's theory proves the uniform ultimate boundedness of the proposed method. Simulation and physical experiments confirm that the technology improves the tracking error convergence speed and stability of robotic fishes.

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Geometrical shape of in-plane inclusion characterized by polynomial internal stress field under uniform eigenstrains

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Applied Mathematics and Mechanics(English Edition) 2016年第9期37卷 1113-1130页

作者： Jian wu c.q.RU Liang ZHANG Ling WAN college of Aerospace Engineering Chongqing University Department of Mechanical Engineering University of Alberta State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology

The internal stress field of an inhomogeneous or homogeneous inclusion in an infinite elastic plane under uniform stress-free eigenstrains is studied. The study is restricted to the inclusion shapes defined by the polynomial mapping functions mapping the exterior of the inclusion onto the exterior of a unit circle. The inclusion shapes, giving a polynomial internal stress field, are determined for three types of inclusions, i.e., an inhomogeneous inclusion with an elastic modulus different from the surrounding matrix, an inhomogeneous inclusion with the same shear modulus but a different Poisson＇s ratio from the surrounding matrix, and a homogeneous inclusion with the same elastic modulus as the surrounding matrix. Examples are presented, and several specific conclusions are achieved for the relation between the degree of the polynomial internal stress field and the degree of the mapping function defining the inclusion shape.

关键词： inclusion shape internal stress field eigenstrain polynomial