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Continuous edge chromatic numbers of abelian group actions

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Science China Mathematics 2025年

作者： Su gao Ruijun Wang Tianhao Wang School of Mathematical Sciences and Laboratory of Pure Mathematics and Combinatorics Nankai University

We prove that for any generating set S of z~n, the continuous edge chromatic number χ′c（G） of the Schreier graph of the Bernoulli shift action G = F(S, 2z~n) is χ′（G） + 1 = |S| + 1. In particular, for the stan...

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Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： zhiqiang Guo Di Lan zirui Jia zhenguo gao Xuetao Shi Mukun He Hua Guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 191-204页

作者： zizhuang He Lingzi Shi Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande gao Panbo Liu School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710129People’s Republic of China School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase ***,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation *** results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial ***,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic ***,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon *** design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption.

关键词： Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption

VISCO-PLASTIC CONSTITUTIVE MODEL FOR UNIAXIAL AND MULTIAXIAL RATCHETING AT ELEVATED TEMPERATURES

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 431-436页

作者： G.z.Kang q.gao J.zhang Dept. of Applied Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 ChinaDept. of Applied Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 ChinaDept. of Applied Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

Based on the experimental results of the ratcheting for SS304 stainless steel, a new visco-plastic cyclic constitutive model was established to describe the uniaxial and multiaxial ratcheting of the material at room and elevated temperatures within the framework of unified visco-plasticity. In the model, the temperature dependence of the ratcheting was emphasized, and the dynamic strain aging occurred in the temperature range of 4 00-600℃ for the material was taken into account particularly. Finally, the prediction capability of the developed model was checked by comparing to the corresponding experimental results.

关键词： constitutive model ratcheting elevated temperature multiaxial loading

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

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Journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang Yang Jianfeng zheng Guoyu Wang Yifei gao Yatao Yang Jia Li Xiaojin Han Yan Cui zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/znAl-LDH z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Ethanol

CALCULATION OF THE DAMPING OF THE zn-27Al ALLOY BASED ON THE MICRO INTERFACE SLIDING MODEL

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 228-234页

作者： Y.z. zhao q. gao Y.C. Liu School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China Department of Applied Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

The microstructures of the zn-27Al alloy after modification, solid-solution treatment, and natural aging were studied. It was clarified why the damping properties of zn-27Al alloys, after treatment, had advanced most on the basis of analyzing the microstructures. Approximate expressions have been educed, which can be used to quantificationally work out the damping of the zn-27Al alloy on the basis of the micro interface sliding model. By comparing the testing damping properties of the foundry zn-27Al alloys and the zn-27Al alloys after modification, solid solution, and natural aging, it was shown that the expressions were rational.

关键词： modification solid solution and aging damping micromechanism micro interface sliding model

Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong gao Huiyu SUN Jianping GU W.M.HUANG College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of Mechanical and Aerospace Engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

关键词： Constitutive equations

Crack Initiation Mechanism of z3CN20.09M Duplex Stainless Steel during Corrosion Fatigue in Water and Air at 290 °C

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Journal of Materials Science & Technology 2015年第11期31卷 1144-1150页

作者： H.C.Wu B.Yang Y.z.Shi q.gao Y.q.Wang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Collaborative Innovation Center of Universal Iron & Steel Technology School of Materials Science and Engineering Anhui University of Technology

The crack initiation mechanism of a z3CN20.09M duplex stainless steel （DSS） during corrosion fatigue （CF） in water and air at 290 ℃ was investigated by using a CF cracking machine and a scanning electron microscopy （SEM）. The cracks were initiated successively at the persistent stip bands （PSBs）, phase boundaries （PBs） and pitting corrosion points （PCPs） of the specimens when they were tested in water at 290 ℃, while in airat 290 ℃ the cracks were only initiated at the PSBs and PBs. And the cracks were found mainly to initiate at the PSBs and PBs when the specimens were tested in water and air at 290 ℃, respectively. The results also reveal that the cracks were likely to be initiated at the first 20% of fatigue life of the specimens tested in water at 290 ℃. However, the cracks were not found until 50% of fatigue life when tested in air at 290 ℃. Moreover, the crack numbers of the specimens tested in water at 290 ℃ were much more than those tested in air at 290 ℃.

关键词： Duplex stainless steel Corrosion fatigue Crack initiation High temperature water

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju zheng Yixin Li Ting zhang Yanlin Fu Peiyan Long Xiao gao zhengwei Wang zhizhong Guan Xiaolan qi Wei Hong Yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK