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Breaking Mirror Circularly Polarized Luminescence of Chiral Metal-Organic Frameworks by High-Pressure Stimulation

CCS Chemistry 2023年第10期5卷 2215-2224页

作者： Laizhi Sui Zhi-Bin Jin Guangming Niu Jutao Jiang Qiao-Hong Li Li-Mei Chang Kaijun Yuan Zhi-Gang Gu Jian Zhang Xueming Yang State Key Laboratory of Molecular Reaction Dynamics and Dalian Coherent Light Source Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 110623 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002 University of Chinese Academy of Sciences Beijing 100049 Marine Engineering College Dalian Maritime UniversityDalian 116026 Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108 Department of Chemistry College of ScienceSouthern University of Science and TechnologyShenzhen 518055

Understanding high-pressure-stimulated circularly polarized luminescence(CPL)of enantiomers remains a challenging but significant task in fundamental research and optical ***,we combined in situ high-pressure photoluminescence with circularly polarized light to study how high pressure stimulated the CPL of crystalline *** lanthanide(Ln)-tartrate(Tar)metal-organic frameworks(MOFs;Ln=Eu,Tb)were synthesized to study their CPL from atmospheric pressure to 10 *** atmospheric pressure,D-and L-Eu(Tar)showed strong andmirror *** intensity changes,emission wavelength shifts,and signal inversions were induced by increasing *** that the D-Eu(Tar)enantiomer showed strong CPL with a maximal dissymmetric factor(g_(lum))of 0.69 under 3 GPa,which is much higher than that under atmospheric pressure and of other reported MOF-based CPL *** interestingly,D-and L-Ln(Tar)enantiomers display obvious asymmetric CPL signals with increasing pressure,demonstrating that high pressure can break the mirror CPL of the MOF *** findings provide a critical understanding on in situ high-pressure CPL of chiral materials and establish a new optical phenomenon where high pressure can break the mirror CPL of enantiomers.

关键词： chirality metal-organic frameworks high pressure circularly polarized luminescence symmetry breaking

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Artificial Ground Motion Simulation with Multi Control Points and Automatic Recognition in Iterative Process 3

Artificial Ground Motion Simulation with Multi Control Point...

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2020 3rd International Symposium on Traffic Transportation and Civil Architecture, ISTTCA 2020

作者： Xie, Haoyu Zheng, Wanshan State Key Laboratory of Bridge Engineering Structural Dynamics Chongqing400067 China CMCT Research and Design Institute Co. LTD Chongqing400067 China School of Civil Engineering Chongqing University Chongqing400045 China

Artificial ground motion simulation with target response spectrum being compatible is a significant challenge for structural seismic design. In the presented scheme, two major modifications are implied on conventional frequency domain methodology as to realize automatic recognition of stubborn points in iterative process and eliminate them by handling multiple control points in frequency domain. The proposed methodology is evaluated by numerical simulation with the target response spectrum from Chinese Specification for Seismic Design of Highway bridges compared with conventional Stochastic Method. The result shows that the presented scheme enables to recognize stubborn points and eliminate them in iterative process as it is designed, and the fitting accuracy is improved considerably. The scheme is verified reliable to generate input ground motion candidates as a reference for engineers to conduct seismic dynamic analysis. © Published under licence by IOP Publishing Ltd.

关键词： Seismic design

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Research of Damper Parameters of Large span Suspension bridge 3

Research of Damper Parameters of Large span Suspension Bridg...

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2020 3rd International Symposium on Traffic Transportation and Civil Architecture, ISTTCA 2020

作者： Wenjun, Gao Yi, Hangyu Chen, Yulong Zhang, Ben State Key Laboratory of Bridge Engineering Structural Dynamics China Merchants Chongqing Communication Research and Design Institute Co. Ltd Chongqing400067 China Chongqing Jiao Tong University School of Civil Engineering Chongqing400041 China

This paper research the parameter selection range of large span suspension bridge dampers. The finite element model of the Puli bridge was established by using ANSYS software. Under consideration of the pile-soil interaction, the cross analysis of 16 dampers with different parameters under the action of longitudinal + vertical earthquake was carried out. The bending moment and shear force at the bottom of the tower, the relative displacement of the tower and the girder, the maximum speed and the maximum damping force of the dampers under different working conditions are analyzed. Therefore, the suggested range of each parameter of a single damper is proposed. © Published under licence by IOP Publishing Ltd.

关键词： Suspension bridges

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Experimental study on the influence of temperature on the wear performance of polymer sliding plate materials for bridge bearings 3

Experimental study on the influence of temperature on the we...

引用

2020 3rd International Symposium on Traffic Transportation and Civil Architecture, ISTTCA 2020

作者： Niu, Songshan Ouyang, Xiankai Liu, Yang State Key Laboratory of Bridge Engineering Structural Dynamics Chongqing400067 China China Merchants Chongqing Communications Technology Research and Design Institute Co. Ltd. Chongqing400067 China Sichuan Xianghui Road and Bridge Engineering Co. Ltd. Chengdu611430 China

The wear performance of polymer sliding plate material for bridge bearing is the key factor affecting the durability of bearing sliding unit. Based on the selection of friction pairs commonly used in bridge bearings in China, the wear performance of modified polytetrafluoroethylene (PTFE) and ultra-high molecular weight polyethylene (UHMWPE) plate, which are gradually used in engineering in recent years, is tested and studied in this paper. It is hoped to provide reference for the engineers and researchers engaged in related work in China. © Published under licence by IOP Publishing Ltd.

关键词： Wear of materials

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Numerical Study of Regular Wave-Induced Oscillatory Soil Response During the Caisson Installation

SSRN

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SSRN 2023年

作者： Duan, Lunliang Qin, Chenxi Tang, Guangwu Wang, Duoyin Meiling, Fan Key Laboratory of Hydraulic and Waterway Engineering Ministry of Education Chongqing Jiaotong University Chongqing400074 China State Key Laboratory of Bridge Structure Dynamics Chongqing Communications Research and Design Institute Chongqing400067 China

The cyclic wave load can change the soil properties around the caisson foundation, which can further affect its stability. In this study, the PORO-FSSI-FOAM model is applied to investigate the wave-induced oscillatory soil response during the caisson installation, where the Reynolds averaged Navier-stokes equation is utilized to simulate the flow motions, and the poro-elastic theory is utilized to govern the wave-induced dynamic response around the caisson foundation. Compared with previous studies on wave-seabed interaction, the effects of caisson installation process are considered in this paper. Firstly, the accuracy of the PORO-FSSI-FOAM model in simulating the wave-induced soil response is validated. Then, the effects of the submerged depth, the geometrical dimensions and the installation sequence of the caisson on the oscillatory pore water response are fully examined using the numerical model. Finally, the momentary seabed liquefaction near caisson foundation during installation process is explored. Numerical results indicate that the caisson dimensions have an impact on the wave-induced pore water pressure response, and the relationship between the oscillatory pore water pressure response and the caisson submerged depth is different at different locations surrounding the structure. Moreover, the installation sequence can greatly affect the momentary soil liquefaction around the caisson foundation. © 2023, The Authors. All rights reserved.

关键词： Pore pressure

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Nondestructive quantitative estimation of cross-sectional corrosion degree of rebar using self-magnetic flux leakage field variation

arXiv

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arXiv 2025年

作者： Qiu, Junli Zhang, Weiping Jiang, Chao Zhang, Hong Zhou, Jianting State Key Laboratory of Mountain Bridge and Tunnel Engineering Chongqing Jiaotong University Chongqing400074 China Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji University 1239 Siping Road Shanghai200092 China Department of Structural Engineering College of Civil Engineering Tongji University 1239 Siping Road Shanghai200092 China

To accurately assess the structural performance of corroded reinforced concrete structures, obtaining precise information on the corrosion range and corrosion degree of rebar is crucial. In this study, based on a comprehensive analysis of extensive high-precision magnetic field and three-dimensional structural light scanning data of 21 corroded rebars, it was found that the self-magnetic flux leakage can accurately identify the corrosion range, with an error not exceeding 3%. A proposed quantitative index NHx of the self-magnetic flux leakage amplitude exhibits a linear correlation with the cross-sectional corrosion degree of rebar, whose probability density distribution can be accurately described using the Weibull distribution function. Utilizing the Weibull distribution function of NHx and a Bayesian model, automatically rapid quantification of the rebar's cross-sectional corrosion degree based on the non-destructive testing-derived NHx values can be conveniently realized. This self-magnetic flux leakage-based novel method for quantifying rebar's cross-sectional corrosion degree is accurate, efficient, and well-suited for practical engineering applications, providing robust support for a precise assessment of the structural performance of corroded reinforced concrete structures. © 2025, CC BY-NC-ND.

关键词： Distribution functions

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On the Melnikov method for fractional-order systems

arXiv

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arXiv 2024年

作者： Li, Hang Shen, Yongjun Li, Jian Dong, Jinlu Hong, Guangyang Key Laboratory of Structural Dynamics of Liaoning Province College of Sciences Northeastern University Shenyang110819 China Department of Mechanical Engineering Shijiazhuang Tiedao University Shijiazhuang050043 China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University Shijiazhuang050043 China

This paper is dedicated to clarifying and introducing the correct application of Melnikov method in fractional dynamics. Attention to the complex dynamics of hyperbolic orbits and to fractional calculus can be, respectively, traced back to Poincaré’s attack on the three-body problem a century ago and to the early days of calculus three centuries ago. Nowadays, fractional calculus has been widely applied in modeling dynamic problems across various fields due to its advantages in describing problems with non-locality. Some of these models have also been confirmed to exhibit hyperbolic orbit dynamics, and recently, they have been extensively studied based on Melnikov method, an analytical approach for homoclinic and heteroclinic orbit dynamics. Despite its decade-long application in fractional dynamics, there is a universal problem in these applications that remains to be clarified, i.e., defining fractional-order systems within finite memory boundaries leads to the neglect of perturbation calculation for parts of the stable and unstable manifolds in Melnikov analysis. After clarifying and redefining the problem, a rigorous analytical case is provided for reference. Unlike existing results, the Melnikov criterion here is derived in a globally closed form, which was previously considered unobtainable due to difficulties in the analysis of fractional-order perturbations characterized by convolution integrals with power-law type singular kernels. Finally, numerical methods are employed to verify the derived Melnikov criterion. Overall, the clarification for the problem and the presented case are expected to provide insights for future research in this topic. © 2024, CC BY-NC-ND.

关键词： Differentiation (calculus)

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Nonlinear Flutter Critical state Prediction for a bridge Girder Based on Instantaneous Power Balance Principle

SSRN

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SSRN 2024年

作者： Cheng, Yue Fang, Genshen Cui, Wei Li, Yongle Zhao, Lin State Key Lab of Disaster Reduction in Civil Engineering Tongji University Shanghai200092 China Key Laboratory of Transport Industry of Wind Resistant Technology for Bridge Structures Tongji University Shanghai200092 China Department of Bridge Engineering Southwest Jiaotong University Sichuan Chengdu610031 China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi University Nanning530004 China Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education Guangxi University Nanning530004 China

With the continuous increase in bridge spans, wind-induced dynamic instability has gradually become a predominant concern in the development of ultra-long-span bridges. Especially for certain bridge sections with blunt aerodynamic configurations, the wind-induced amplitude of bridge girders gradually increases after crossing the flutter critical state, however maintain certain stable motion pattern, exhibiting as limit cycle oscillation with single degree of freedom (DoF) torsional or bending-torsional coupled motion, which is defined as hysteresis flutter or soft flutter. Extensive research on the nonlinear hysteresis flutter and its mechanisms have been conducted. However, the existing flutter prediction algorithms are mostly based on the principle of force balance and flutter critical state is identified using the assumption of generalized mode damping ratio as zero. Since higher-order aerodynamic damping terms are present in the self-excited force, the traditional algorithm becomes ineffective or even misleading. Based on the structural motion equilibrium equations during flutter limit cycle oscillations, a bridge flutter estimation framework is proposed using the instantaneous power balance (IPB) principle. This framework accounts for the energy input-output balance relationship during flutter hysteresis motion and achieves the energy equilibrium state through a nonlinear parameter optimization approach. Using a closed box girder section as an example and considering amplitude-dependent nonlinearity of key parameters such as structural damping and flutter derivatives, the accuracy of the algorithm in this paper was validated through wind tunnel experiments. The nonlinear bending-torsional coupled characteristics during hysteresis flutter were therefore discussed, achieving a comprehensive evaluation of the flutter state of the bridge section from the flutter critical to post-flutter states. By employing the proposed methodology, it is possible to identify multi

关键词： Damping

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Nonlinear state-Space Model of Self-Excited Forces for Bluff Body Aeroelasticity

SSRN

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SSRN 2023年

作者： Gao, Guangzhong Zhu, Ledong Øiseth, Ole Andre Li, Jiawu Department of Bridge Engineering Highway College Chang’an University Xi’an710064 China Department of Bridge Engineering Tongji University Shanghai200092 China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University Shanghai200092 China Key Laboratory of Transport Industry of Bridge Wind Resistance Technology Tongji University Shanghai200092 China Department of Structural Engineering Norwegian University of Science and Technology Trondheim7491 Norway

This paper presents a novel state-space model of nonlinear self-excited forces to capture the amplitude dependency and unsteady effect for bluff body aeroelasticity. In the present form, this model represents a theoretical extension of classical linear state-space model to the nonlinear regime, where bluff sections undergo large amplitude oscillations. The proposed model introduces additional state variables to approximate nonlinear convolution-based indicial functions and thus offers a useful tool to estimate nonlinear wind-induced instabilities including nonlinear flutter limit cycle oscillation (LCO), vortex induced vibration (VIV) and unsteady galloping. We also develop the analytical basis for nonlinear parameters identification based on equivalent linearization of the nonlinear transfer functions and numerical solving algorithm of nonlinear governing equations. The feasibility of this model is comprehensively validated through experimental results of nonlinear flutter and unsteady galloping of two typical bluff sections. This model also lies the basis for a nonlinear analytical framework in time domain to incorporate both aerostatic and structural nonlinearities in full structural analysis. © 2023, The Authors. All rights reserved.

关键词： Transfer functions

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Influence of Water Content and Lateral Pressure on Coal-Rock Wellbore Stability Under Biaxial Compression

SSRN

引用

SSRN 2024年

作者： Liu, Xudong Liu, Wei Wei, Yuanlong Zhang, Xiong Zhao, Fuping Zhao, Lingyun Fu, Yinlan Jiang, Deyi Li, Jianghao Li, Depeng State Key Laboratory of Coal Mine Disasters Dynamics and Control Chongqing University Chongqing400044 China Guizhou Oil and Gas Exploration and Development Engineering Research Institute Guiyang550081 China Key Laboratory of Unconventional Gas Evaluation and Development in Complex Structural Areas Guiyang550081 China

It is of great significance to analyze the failure form and crack expansion patterns around the coal-rock cavity for exploring the mechanism of wellbore instability in barefoot interval of multi-branch horizontal well. In order to better study the effects of water content and lateral pressure on the wellbore stability of barefoot interval of multi-branch horizontal wells, based on acoustic emission (AE) and digital image correlation (DIC) technologies, a series of biaxial compression tests of coal-rock with hole under different water content and lateral pressure were carried out for in Bijie experimental region of Guizhou Province. Furthermore, the failure modes and crack expansion patterns around coal-rock wellbore with different water content and lateral pressure were compared and analyzed. The results show that: (1) Water has a certain influence on the mechanical properties of coal-rock in the Bijie Experimental Region. The peak strength and peak strain both decrease with the increase of water content, and the elastic modulus is relatively little affected by water content. (2) The failure characteristics of coal-rock with different water content under biaxial compression test presents the composite failure modes of tension-shear, and is dominated by tensile failure. (3) The peak strength and peak strain of coal-rock increase in a power function form with the increase of (Symbol Presented)2, and the elastic modulus also increases slightly with the increase of (Symbol Presented)2. (4) Under different (Symbol Presented)2 conditions, the initial failure of coal samples mostly starts from the coal-rock wellbore and the vicinity of primary fractures. As the biaxial stress difference decreases, the self-stabilization time of coal samples increases. (5) The selection of wells ((Symbol Presented)1-(Symbol Presented)2) and the selection of wells with small Cov can effectively increase the stability performance of barefoot interval of coal reservoirs and reduce the risk of

关键词： Ductile fracture

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