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A novel relationship between elastic modulus and void ratio associated with principal stress for coral calcareous sand

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1033-1048页

作者： Ran gao Jianhong ye State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Elastic moduli,e.***.shear modulus G and bulk modulus K,are important parameters of geotechnical materials,which are not only the indices for the evaluation of the deformation ability of soils but also the important basic parameters for the development of the constitutive models of geotechnical materials.In this study,a series of triaxial loading-unloading-reloading shear tests and isotropic loading-unloadingreloading tests are conducted to study several typical mechanical properties of coral calcareous sand(CCS),and the void ratio evolution during loading,unloading and reloading.The test results show that the stress-strain curves during multiple unloading processes are almost parallel,and their slopes are much greater than the deformation modulus at the initial stage of loading.The relationship between the confining pressure and the volumetric strain can be defined approximately by a hyperbolic equation under the condition of monotonic loading of confining pressure.Under the condition of confining pressure unloading,the evolution of void ratio is linear in the e-lnp0 plane,and these lines are a series of almost parallel lines if there are multiple processes of unloading.Based on the experimental results,it is found that the modified Hardin formulae for the elastic modulus estimation have a significant deviation from the tested values for CCS.Based on the experimental results,it is proposed that the elastic modulus of soils should be determined by the intersection line of two spatial surfaces in the G/K-e-p’/pa space(pa:atmosphere pressure).“ye formulation”is further proposed for the estimation of the elastic modulus of CCS.This new estimation formulation for soil elastic modulus would provide a new method to accurately describe the mechanical behavior of granular soils.

关键词： Coral calcareous sand(CCS) Elastic shear modulus Elastic bulk modulus Triaxial test Estimation formulation ye formulation

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Cardiac remodeling in patients with atrial fibrillation reversing bradycardia-induced cardiomyopathy:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1339-1345页

作者： De-Kui gao Xiang-Lin ye Zhen Duan hong-Yang Zhang Tao Xiong Zheng-hong Li Hai-Feng Pei Department of Cardiology Jiangyou Second People's HospitalJiangyou 621701Sichuan ProvinceChina Department of Cardiology The General Hospital of Western Theater CommandChengdu 610083Sichuan ProvinceChina Department of Clinical Medicine Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Special Inspection Jiangyou Second People's HospitalJiangyou 621701Sichuan ProvinceChina

BACKGROUND Bradycardia-induced cardiomyopathy(BIC),which is a disease resulting from bradycardia,is characterized by cardiac chamber enlargement and diminished cardiac function.The correction of bradycardia can allow for significant improvements in both cardiac function and structure;however,this disease has been infrequently documented.In this case,we conducted a longitudinal followup of a patient who had been enduring BIC for more than 40 years to heighten awareness and prompt timely diagnosis and rational intervention.CASE SUMMARY A woman who presented with postactivity fatigue and dyspnea was diagnosed with bradycardia at the age of 7.Since she had no obvious symptoms,she did not receive any treatment to improve her bradycardia during the 42-year follow-up,except for the implantation of a temporary pacemaker during labor induction surgery.As time progressed,the patient's heart gradually expanded due to her low ventricular rate,and she was diagnosed with BIC.In 2014,the patient developed atrial fibrillation,her ventricular rate gradually increased,and her heart shape gradually returned to normal.This report describes the cardiac morphological changes caused by the heart rate changes in BIC patients older than 40 years,introduces another possible outcome of BIC,and emphasizes the importance of early intervention in treating BIC.CONCLUSION BIC can induce atrial fibrillation,causing an increased ventricular rate and leading to positive cardiac remodeling.

关键词： Bradycardia cardiomyopathy Heart rate Atrial fibrillation Cardiac dilatation Case report

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Tuning the surface electronic structure of noble metal aerogels to promote the electrocatalytic oxygen reduction

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Journal of Energy Chemistry 2024年第2期89卷 557-564,I0013页

作者： hongxing Yuan Wei gao Xinhao Wan Jianqi ye Dan Wen State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072ShaanxiChina

The sluggish kinetics of the oxygen reduction reaction(ORR)is the bottleneck for various electrochemical energy conversion devices.Regulating the electronic structure of electrocatalysts by ligands has received particular attention in deriving valid ORR electrocatalysts.Here,the surface electronic structure of Ptbased noble metal aerogels(NMAs)was modulated by various organic ligands,among which the electron-withdrawing ligand of 4-methylphenylene effectively boosted the ORR electrocatalysis.Theoretical calculations suggested the smaller energy barrier for the transformation of O^(*) to OH^(*) and downshift the d-band center of Pt due to the interaction between 4-methylphenylene and the surface metals,thus enhancing the ORR intrinsic activity.Both Pt3Ni and Pt Pd aerogels with 4-methylphenylene decoration performed significant enhancement in ORR activity and durability in different media.Remarkably,the 4-methylphenylene modified Pt Pd aerogel exhibited the higher halfwave potential of 0.952 V and the mass activity of 10.2 times of commercial Pt/C.This work explained the effect of electronic structure on ORR electrocatalytic properties and would promote functionalized NMAs as efficient ORR electrocatalysts.

关键词： Noble metal aerogels Surface electronic structure ORR Electrocatalyst Organic ligands

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Full-parameter omnidirectional transformation optical devices

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National Science Review 2024年第3期11卷 92-99页

作者： Yuan gao Yu Luo Jingjing Zhang Zhengjie Huang Bin Zheng hongsheng Chen Dexin ye Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and InstrumentationZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang University School of Electrical and Electronic Engineering Nanyang Technological University CNRS-InternationalNTU-Thales Research Alliance Nanyang Technological University Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University International Joint Innovation Center The Electromagnetics Academy at Zhejiang University Zhejiang University Key Laboratory of Advanced Micro/Nano Electronic Devices&Smart Systems of Zhejiang Jinhua Institute of Zhejiang UniversityZhejiang University Shaoxing Institute of Zhejiang University Zhejiang University

Transformation optics(TO) provides an unprecedented technique to control electromagnetic(EM) waves by engineering the constitutive parameters of the surrounding medium through a proper spatial transformation. In general, ideal transformation optical devices require simultaneous electric and magnetic responses along all three dimensions. To ease the practical implementation, previous studies usually made use of reduced parameters or other simplified approaches, which inevitably introduce extra reflection or unwanted phase shift. Up to today, experimental realizations of full-parameter transformation optical devices in free space are still quite limited. Here, a general design strategy is proposed to solve this problem.As a specific example, a full-parameter spatial-compression TO medium with constitutive parameters taking the diagonal form diag(a, a, 1/a) for the TM wave incidence was designed and realized experimentally. Such spatial-compression TO media were then applied to the implementation of an ideal omnidirectional invisibility cloak capable of concealing a large-scale object over a wide range of illumination angles. Both the simulation and experiment confirm that the cloak allows for nearly unity transmission of EM waves in the forward direction without introducing extra scattering or phase shift. This work constitutes an important stepping stone for future practical implementation of arbitrary full-parameter omnidirectional transformation optical devices.

关键词： transformation optical devices omnidirectional impedance matching full-parameter invisibility cloak

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Preface: The Special Issue on Dynamic and Networking Games

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Journal of the Operations Research Society of China 2024年第1期12卷 1-3页

作者： hong-Wei gao Vladimir Mazalov School of Mathematics and Statistics Qingdao University266071QingdaoShandongChina Institute of Applied Mathematical Research Karelian Research Centre of RAS185910PetrozavodskRussia

Numerous game theory-based techniques to characterize agent behavior haveemerged in response to the swift advancements in technology,communications,indus-trial organization,economic integration,and international trade.There is a huge varietyof mathematical techniques used in game theory.The application of dynamic and net-working game techniques is the main topic of this special issue.Studying strategicinteractions between many decision-makers with dynamic and varied connections isthe focus of research in the game theory discipline of dynamic and networking games.This field of study examines how agents or people make choices in dynamic circum-stances and how those choices impact their overall outcomes and payoffs.

关键词： agent strategic advancement

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Effects of orientation on the fatigue crack growth behaviors of the ZK60 magnesium alloy in air and PBS

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Journal of Magnesium and Alloys 2024年第1期12卷 281-294页

作者： Jiaqi Hu Zheng Liu Zuoliang Ning hong gao School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Chemical Process Safety and Equipment Technology Tianjin 300072China

Strong anisotropic corrosion and mechanical properties caused by specimen orientations greatly limit the applications of wrought magnesium alloys.To investigate the influences of specimen orientation,the corrosion tests and(corrosion)fatigue crack growth tests were conducted.The rolled and transverse surfaces of the materials show distinct corrosion rate differences in the stable corrosion stage,but the truth is the opposite for the initial stage of corrosion.In air,specimen orientations have a significant influence on the plastic deformation mechanisms near the crack tip,which results in different fatigue fracture surfaces and cracking paths.Compared with R-T specimens,N-T specimens show a slower fatigue crack growth(FCG)rate in air,which can be attributed to crack closure effects and deformation twinning near the crack tip.The corrosion environment will not significantly change the main plastic deformation mechanisms for the same type of specimen.However,the FCG rate in phosphate buffer saline(PBS)is one order of magnitude higher than that in air,which is caused by the combined effects of hydrogen-induced cracking and anodic dissolution.Owing to the similar corrosion rates at crack tips,the specimens with different orientations display close FCG rates in PBS.

关键词： Magnesium alloy Orientation Corrosion Fatigue crack growth

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Associations between Social Media Use and Sleep Quality in China:Exploring the Mediating Role of Social Media Addiction

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International Journal of Mental Health Promotion 2024年第5期26卷 361-376页

作者： Yijie ye Han Wang Liujiang ye Hao gao School of Journalism and Communication Nanjing Normal UniversityNanjing210097China School of Journalism and Communication Jinan UniversityGuangzhou510632China

Sleep quality is closely linked to people’s health,and during the COVID-19 pandemic,the sleep patterns of residents in China were notably poor.The lockdown in China led to an increase in social media use,prompting questions about its impact on sleep.Therefore,this study investigates the association between social media use and sleep quality among Chinese residents during the COVID-19 outbreak,highlighting the potential mediating role of social media addiction.Data were collected via questionnaires through a cross-sectional survey with 779 valid responses.Variance analysis was used to test for differences in social media use among different demographic variables.Bivariate correlation analysis was employed to explore the relationships between variables,while regression analysis investigated the correlations between various media factors and sleep quality.Additionally,Bootstrap sampling was utilized to analyze the potential mediating influence of social media addiction in the relationship between social media use and sleep.The study's findings reveal a significant correlation between social media use,particularly before bedtime,and sleep quality(p<0.01),with pre-sleep activity notably linked to poorer overall sleep scores(β=0.141,p=0.004).Although the daily use of social media did not directly impact most individuals’sleep quality,specific platforms like news apps,short video apps,dating apps,and content community platforms were associated with higher levels of social media addiction,subsequently negatively affecting sleep quality.Specifically,the use of news apps(B=0.068,95%CI[0.000,0.019]),short video apps(B=0.112,95%CI[0.001,0.031]),dating apps(B=0.147,95%CI[0.000,0.028]),and content community platforms(B=0.106,95%CI[0.001,0.028])was found to increase the risk of social media addiction,subsequently leading to adverse effects on sleep quality.The study underscores a notable link between social media use and sleep quality,suggesting that mindful social media habits,particularly before bedtime,and reducing addiction

关键词： Social media use social media addiction sleep quality

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Research on ozone formation sensitivity based on observational methods:Development history,methodology,and application and prospects in China

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Journal of Environmental Sciences 2024年第4期138卷 543-560页

作者： Wanghui Chu hong Li Yuanyuan Ji Xin Zhang Likun Xue Jian gao Cong An State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environment Research Institute Shandong UniversityQingdao 266237China

Observation-based method for O_(3)formation sensitivity research is an important tool to analyze the causes of ground-level O_(3)pollution,which has broad application potentials in determining the O_(3)pollution formation mechanism and developing prevention and control strategies.This paper outlined the development history of research on O_(3)formation sensitivity based on observational methods,described the principle and applicability of the methodology,summarized the relative application results in China and provided recommendations on the prevention and control of O_(3)pollution in China based on relevant study results,and finally pointed out the shortcomings and future development prospects in this field in China.The overview study showed that the O_(3)formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO_(x)-limited regime due to the implementation of the O_(3)precursors emission reduction policies;O_(3)pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O_(3)pollution control measures should be improved.There are still some current deficiencies in the study field in China.Therefore,it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved;the atmospheric chemical mechanisms should be vigorously developed,and standardized methods for determining the O_(3)formation sensitivity should be established in China in the near future.

关键词： Observation-based method Ozone formation sensitivity Ozone pollution prevention and control VOCs NO_(x) OBM

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Bilayer borophene:an efficient catalyst for hydrogen evolution reaction

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 13-23页

作者： Na Xing Nan gao Panbin ye Xiaowei Yang Haifeng Wang Jijun Zhao College of Sciences/Xinjiang Production&Construction Corps Key Laboratory of Advanced Energy Storage Materials and Technologies Shihezi UniversityShihezi832000China Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)Dalian University of TechnologyDalian116024China School of Materials Science and Engineering Taizhou UniversityTaizhou318000China

The electrocatalytic hydrogen evolution reaction is a crucial technique for green hydrogen production.However,finding affordable,stable,and efficient catalyst materials to replace noble metal catalysts remains a significant challenge.Recent experimental breakthroughs in the synthesis of two-dimensional bilayer borophene provide a theoretical framework for exploring their physical and chemical properties.In this study,we systematically considered nine types of bilayer borophenes as potential electrocatalysts for the hydrogen evolution reaction.Our first-principles calculations revealed that bilayer borophenes exhibit high stability and excellent conductivity,possessing a relatively large specific surface area with abundant active sites.Both surface boron atoms and the bridge sites between two boron atoms can serve as active sites,displaying high activity for the hydrogen evolution reaction.Notably,the Gibbs free energy change associated with adsorption for these bilayer borophenes can reach as low as−0.002 eV,and the Tafel reaction energy barriers are lower(0.70 eV)than those on Pt.Moreover,the hydrogen evolution reaction activity of these two-dimensional bilayer borophenes can be described by engineering their work function.Additionally,we considered the effect of pH on hydrogen evolution reaction activity,with significant activity observed in an acidic environment.These theoretical results reveal the excellent catalytic performance of two-dimensional bilayer borophenes and provide crucial guidance for the experimental exploration of multilayer boron for various energy applications.

关键词： bilayer borophene hydrogen evolution reaction work function pH effect

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Irrational-Behavior-Proof Conditions for Stochastic Games over Event Trees

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Journal of the Operations Research Society of China 2024年第1期12卷 243-263页

作者： Lei Wang Cui Liu hong-Wei gao Chong Lin School of Automation Institute of Complexity ScienceQingdao UniversityQingdao 266071ShandongChina School of Mathematics and Statistics Institute of Applied Mathematics of ShandongQingdao UniversityQingdao 266071ShandongChina

In this paper,the irrational-behavior-proof conditions in a class of stochastic dynamic games over event trees are presented.Four kinds of irrational-behavior-proof conditions are proposed by the imputation distribution procedure,and their relationships are discussed.More specific properties for the general transformation of characteristic functions are developed,based on which,the irrational-behavior-proof conditions are proved to be true in a transformed cooperative game.

关键词： Dynamic cooperative game Event tree Irrational-behavior-proof condition Imputation distribution procedure Transformation of characteristic function

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