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A vertical track nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 931-946页

作者： Meng LI Hu DING Shanghai Key laboratory of Mechanics in Energy engineering School of Mechanics and Engineering ScienceShanghai Frontier Science Center of MechanoinformaticsShanghai UniversityShanghai 200444China

Eliminating the effects of gravity and designing nonlinear energy sinks(NESs)that suppress vibration in the vertical direction is a challenging task with numerous damping *** this paper,the dynamic design of a vertical track nonlinear energy sink(VTNES)with zero linear stiffness in the vertical direction is proposed and realized for the first *** motion differential equations of the VTNES coupled with a linear oscillator(LO)are *** the strong nonlinearity considered of the VTNES,the steady-state response of the system is analyzed with the harmonic balance method(HBM),and the accuracy of the HBM is verified *** this basis,the VTNES prototype is manufactured,and its nonlinear stiffness is *** damping effect and dynamic characteristics of the VTNES are studied theoretically and *** results show that the VTNES has better damping effects when strong modulation responses(SMRs)***,even for small-amplitude vibration,the VTNES also has a good vibration suppression *** sum up,in order to suppress the vertical vibration,an NES is designed and developed,which can suppress the vertical vibration within certain ranges of the resonance frequency and the vibration intensity.

关键词： track nonlinear energy sink(TNES) vertical direction gravity nonlinear stiffness harmonic balance method(HBM) vibration control

Cross-linked Electrospun Gel Polymer Electrolytes for Lithium-Ion Batteries

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Chinese Journal of Polymer science 2024年第8期42卷 1021-1028页

作者： Xue Gong Qin Xiao Qing-Yin Li Wen-Cui Liang Feng Chen Long-Yu Li Shi-Jie Ren College of Polymer science and engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage ***,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical *** obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled Li/LiFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 *** results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for Lithium-ion battery applications that require high-temperature usage.

关键词： Electrospinning Cross-linked Gel polymer electrolytes Lithium-ion batteries

The Effect of Blending Ratio on the Structure and Properties of the PPR/PS In situ Fiber Reinforced System Prepared by Multi-Flow Vibration Injection Molding

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Chinese Journal of Polymer science 2024年第6期42卷 851-863页

作者： Yan-Jiang Li Meng-Long Hu Jun-Wen Zhang Qiang Fu Jie Zhang College of Polymer science and engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

To enhance the mechanical properties of polypropylene random copolymer(PPR),polystyrene(PS)with four different contents were added to the PPR matrix through melt ***,using the Multi-Flow Vibration Injection Molding(MFVIM)technology,PPR/PS in situ microfiber composites(MFC)with different blending ratios were *** results indicated that blending ratio had a great impact on the phase morphology and crystal structure of MFVIM samples,which was different from those of conventional injection molding(CIM)*** ultrafine fibers could be formed under the shear field and could absorb the PPR molecular chains to form hybrid shish-kebab ***,the PPR matrix could also form shish-kebab structures under the effect of strong *** the PS content reached 20%,under the combined action of PS in situ microfibers and highly oriented crystal structure,the tensile strength and Young’s modulus of the sample were obviously improved and the impact strength remained at a relatively high *** a strong and tough balanced PPR based material was *** results provide valuable insights for expanding the industrial and daily-life applications of PPR and show promising development prospects.

关键词： PPR MFVIM In situ microfibers Shearfield Hybrid shish-kebab structures

Non-destructive buffer enabling near-infrared-transparent inverted inorganic perovskite solar cells toward 1400 h light-soaking stable perovskite/Cu（In,Ga）Se2 tandem solar cells

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Journal of Energy Chemistry 2024年第10期97卷 622-629页

作者： Yu Zhang Zhaoheng Tang Zhongyang Zhang Jiahong Tang Minghua Li Siyuan Zhu Wenyan Tan Xi Jin Tongsheng Chen Jinsong Hu Chao Zhou Chunlei Yang Qijie Liang Xugang Guo Weimin Li Weiqiang Chen Yan Jiang MOE Key laboratory of Laser Life science & Guangdong Provincial Key laboratory of Laser Life science Guangzhou Key Laboratory of Spectral Analysis and Functional Probes College of Biophotonics South China Normal University School of Materials science and engineering Beijing Institute of Technology Songshan Lake Materials laboratory Department of Materials science and engineering Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology Beijing Advanced Innovation Center for Soft Matter science and engineering College of Chemical Engineering College of Materials Science and Engineering Beijing University of Chemical Technology Department of Physics Liaoning University Beijing National laboratory for Molecular sciences (BNLMS) Institute of Chemistry Chinese Academy of Sciences School of Physics and Materials science Guangzhou University Shenzhen Institute of Advanced Technology Chinese Academy of Sciences

Near-infrared（NIR） transparent inverted all-inorganic perovskite solar cells（PSCs） are excellent top cell candidates in tandem *** essential challenge is the replacement of metal contacts with transparent conductive oxide（TCO） electrodes,which requires the introduction of a buffer layer to prevent sputtering *** this study,we show that the conventional buffers（i.e.,small organic molecules and atomic layer deposited metal oxides） used for organic-inorganic hybrid perovskites are not applicable to all-inorganic perovskites,due to non-uniform coverage of the vulnerable layers underneath,deterioration upon ion bombardment and moisture induced perovskite phase transition,A thin film of metal oxide nanoparticles by the spin-coating method serves as a non-destructive buffer layer for inorganic ***-inorganic inverted near-infrared-transparent PSCs deliver a PCE of 17.46% and an average transmittance of 73.7% between 780 and 1200 *** combination with an 18.56% Cu（In,Ga）Se2bottom cell,we further demonstrate the first all-inorganic perovskite/CIGS 4-T tandem solar cell with a PCE of 24.75%,which exhibits excellent illumination stability by maintaining 86.7% of its initial efficiency after 1400 *** non-destructive buffer lays the foundation for efficient and stable NIR-transparent inverted inorganic perovskite solar cells and perovskite-based tandems.

关键词： Buffer layer CsPbI3 perovskite Inverted perovskite solar cells Stability Tandem solar cells

Adaptive sampling for corrugated plate digitization using a laser displacement sensor

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science China(Technological sciences) 2024年第5期67卷 1510-1523页

作者： WU ChengXing QI Qi CHEN BaiJin YANG JiXiang DING Han State Key laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key laboratory of Intelligent Manufacturing Equipment and Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

The surface quality of a corrugated plate directly determines the heat transfer property of the thermal power mechanical *** detection methods are impractical for real-world production,being slow and *** contrast,the point laser displacement sensor,employing the optical triangle method,emerges as a promising device for assessing parts with variable curvature and highly reflective *** its benefits,high-density sampling by an innate frequency introduces challenges such as data redundancy and a poor signal-to-noise ratio,potentially affecting the efficiency and precision of subsequent data *** address these challenges,adjustable frequency data sampling has been developed for this sensor,allowing adaptive sampling for corrugated plate *** process begins with surface digitization to extract discrete points,which are transformed into intersection curves using the B-spline fitting ***,dominant points are identified,considering multigeometric constraints for curvature and arch ***,the sampling signal is adjusted based on the distribution information of dominant *** results indicate that the proposed method effectively minimizes redundant sampling without compromising the accurate capture of essential geometric features.

关键词： corrugated plate laser displacement sensor adaptive sampling dominant point curvature arch height

Spectroscopy and molecule opacity investigation on excited states of SiS

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Chinese Physics B 2024年第5期33卷 381-387页

作者：李瑞吕浩男桑纪群刘晓华梁桂颖吴勇 College of Teacher Education Qiqihar UniversityQiqihar 161006China National Key laboratory of computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Department of Physics College of ScienceQiqihar UniversityQiqihar 161006China School of Data science and Artificial Intelligence Jilin Engineering Normal UniversityChangchun 130052China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100084China

The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many *** to complex interactions among its low-lying electronic states,precise information regarding the molecular structure of SiS is *** obtain accurate information about the structure of its excited states,the high-precision multireference configuration interaction(MRCI)method has been *** method is used to calculate the potential energy curves(PECs)of the 18Λ–S states corresponding to the lowest dissociation limit of *** core–valence correlation effect,Davidson’s correction and the scalar relativistic effect are also included to guarantee the precision of the MRCI *** on the calculated PECs,the spectroscopic constants of quasi-bound and bound electronic states are calculated and they are in accordance with previous experimental *** transition dipole moments(TDMs)and dipole moments(DMs)are determined by the MRCI *** addition,the abrupt variations of the DMs for the 1^(5)Σ^(+)and 2^(5)Σ^(+)states at the avoided crossing point are attributed to the variation of the electronic *** opacity of SiS at a pressure of 100 atms is presented across a series of *** increasing temperature,the expanding population of excited states blurs the band boundaries.

关键词： SiS opacity excited state spectroscopic constant configuration interaction

On the low cycle fatigue behaviour of an Al-Zn-Mg-Cu alloy processed via non-isothermal ageing

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Journal of Materials science & Technology 2024年第1期168卷 227-238页

作者： Guangyi Guo Guofu Xu Yuan Tang Zhihao Zhao Zhihao Yi Haoran Li Ruohan Wang Xiaoyan Peng School of Materials science and engineering Central South UniversityChangsha 410083China Key laboratory of Nonferrous Materials science and engineering of Ministry of Education Changsha 410083China

The low cycle fatigue behaviour of an Al-Zn-Mg-Cu alloy processed via non-isothermal ageing(NIA)was examined at different strain *** showed that NIA improved the low cycle fatigue life(more than 7000 cycles)by optimising the precipitate configuration within 5.5 h while maintaining comparable mechanical properties(570 MPa for tensile strength)and conductivity(nearly 39%IACS)to conventional isothermal ageing,*** observation combined with molecular dynamic simula-tion revealed that precipitation configuration manipulated by NIA had a crucial effect on fatigue resis-tance.A great number of repeatedly sheared and locally destructed GP zones enhanced co-planar slip and slip localisation in the under-aged alloy during the early stage of NIA,responsible for the dramatic displacement steps on the surface and resultant poor fatigue *** the NIA further proceeded,moderately coarsened precipitates with an average dimension of 6.0 nm and elevated number density ef-fectively impeded the dislocation movement and weaken the slip localisation to a great extent,improving the fatigue performance within a few hours.

关键词： Non-isothermal ageing Fatigue Al-Zn-Mg-Cu alloy Precipitate manipulation Slip localization

Nonlinear dynamics of a circular curved cantilevered pipe conveying pulsating fluid based on the geometrically exact model

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 261-276页

作者： Runqing CAO Zilong GUO Wei CHEN Huliang DAI Lin WANG Department of engineering Mechanics School of Aerospace EngineeringHuazhong University of Science and TechnologyWuhan 430074China Hubei Key laboratory for engineering Structural Analysis and Safety Assessment Wuhan 430074China State Key laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Due to the novel applications of flexible pipes conveying fluid in the field of soft robotics and biomedicine,the investigations on the mechanical responses of the pipes have attracted considerable *** fluid-structure interaction(FSI)between the pipe with a curved shape and the time-varying internal fluid flow brings a great challenge to the revelation of the dynamical behaviors of flexible pipes,especially when the pipe is highly flexible and usually undergoes large *** this work,the geometrically exact model(GEM)for a curved cantilevered pipe conveying pulsating fluid is developed based on the extended Hamilton's *** stability of the curved pipe with three different subtended angles is examined with the consideration of steady fluid *** attention is concentrated on the large-deformation resonance of circular pipes conveying pulsating fluid,which is often encountered in practical *** constructing bifurcation diagrams,oscillating shapes,phase portraits,time traces,and Poincarémaps,the dynamic responses of the curved pipe under various system parameters are *** mean flow velocity of the pulsating fluid is chosen to be either subcritical or *** numerical results show that the curved pipe conveying pulsating fluid can exhibit rich dynamical behaviors,including periodic and quasi-periodic *** is also found that the preferred instability type of a cantilevered curved pipe conveying steady fluid is mainly in the flutter of the second *** a moderate value of the mass ratio,however,a third-mode flutter may occur,which is quite different from that of a straight pipe system.

关键词： curved pipe conveying fluid pulsating fluid geometrically exact model(GEM) nonlinear dynamics parametric vibration flutter

A review of rock macro-indentation:Theories,experiments,simulations,and applications

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Journal of Rock Mechanics and Geotechnical engineering 2024年第6期16卷 2351-2374页

作者： Weiqiang Xie Xiaoli Liu Xiaoping Zhang Xinmei Yang Xiaoxiong Zhou State Key laboratory of Hydroscience and engineering Tsinghua UniversityBeijing100084China Yunlong Lake laboratory of Deep Underground science and engineering Xuzhou221116China State Key laboratory of Water Resources and Hydropower engineering science Wuhan UniversityWuhan430072China

Rock macro-indentation plays a fundamental role in mechanical rock breaking for various rock engineering application,such as drilling,tunneling,cutting,and *** the past decades,extensive research has been conducted to understand the indentation mechanisms and responses through various *** review aims to provide an overview of the current status and recent advancements in theories,experiments,numerical simulations,and applications of macro-indentation in rock *** starts with elaborating on the mechanisms of macro-indentation,followed by a discussion of the merits and limitations of commonly used *** factors and their effects on indentation test results are then *** numerical simulation methods for rock macro-indentation are highlighted,along with their advantages and ***,the applications of indentation tests and indentation indices in characterizing rock properties are *** reveals that compression-tension,compression-shear,and composite models are widely employed in rock *** the compression-tension model is straightforward to use,it may overlook the anisotropic properties of *** the other hand,the composite model provides a more comprehensive description of rock indentation but requires complex ***,factors,such as indentation rate,indenter geometry,rock type,specimen size,and confining pressure,can significantly influence the indentation *** methods for macro-indentation encompass continuous medium,discontinuous medium,and continuous-discontinuous medium methods,with selection based on their differences in ***,rock macro-indentation can be practically applied to mining engineering,tunneling engineering,and petroleum drilling *** indices serve as valuable tools for characterizing rock strength,brittleness,and *** review sheds light on the development of rock macro-inde

关键词： Rock macro-indentation Indentation test Indentation indices Mechanism Rock breaking