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Journal of Magnesium and Alloys 2024年第1期12卷 361-383页

作者： chao Xie Shijie Bai Xiao Liu Minghua zhang Jianke Du The Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211P.R.China Key Laboratory of High Temperature Wear Resistant Materials Preparation Technology of Hunan Province Hunan University of Science and TechnologyXiangtan 411201P.R.China

In this study,a phase-field scheme that rigorously obeys conservation laws and irreversible thermodynamics is developed for modeling stress-corrosion coupled damage(SCCD).The coupling constitutive relationships of the deformation,phase-field damage,mass transfer,and electrostatic field are derived from the entropy *** SCCD localization induced by secondary phases in Mg is numerically simulated using the implicit iterative algorithm of the self-defined finite *** quantitative evaluation of the SCCD of a C-ring is in good agreement with the experimental *** capture the damage localization,a micro-galvanic corrosion domain is defined,and the buffering effect on charge migration is *** cases are investigated to reveal the effect of localization on corrosion acceleration and provide guidance for the design for resistance to SCCD at the crystal scale.

关键词： Phase field Mg alloys Stress-corrosion coupled damage Damage localization Finite element method

Mobility of rhenium and selenium during chemical weathering and their implication for petrogenic organic carbon oxidation

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Science China Earth Sciences 2024年第3期67卷 740-750页

作者： Yuhong zhang Jin WANG Yuanxin QU chao ZHU zhangdong JIN State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China

The oxidative weathering of petrogenic organic carbon(OC_(petro)) is an important source of carbon dioxide(CO_(2)) into the atmosphere on geological timescales and significantly influences the carbon cycle and global climate change. However, at present, a robust proxy to assess OC_(petro)oxidation is lacking. Riverine rhenium(Re) has emerged as a potential proxy to trace OC_(petro)oxidation, but little is known about Re sources and its relationship with OC_(petro)oxidation. To better understand the robustness of this proxy, we analyzed a shale weathering profile from the early Cambrian Shuijingtuo Formation in Chengkou County, Chongqing City, to address the mobility of Re and selenium(Se) and their relationship with the oxidation of OC_(petro)by analyses of the elemental variation and sequential extraction. The results showed that the chemical index of alteration(CIA)increases from the fresh bedrock to the weathered sections, indicating enhanced weathering intensity. Based on the sequential extraction and mass transfer coefficients(τ), Re and Se mainly exist in the organic phase of shale and are paired lost with OC_(petro) during weathering, with no obvious correlation with sulfide minerals. Furthermore, the different proportions of Re and Se loss with OC_(petro) loss can be attributed to their different geochemical behaviors during weathering. Our study supports Re as a robust proxy to trace OC_(petro) oxidation, whereas Se is the potential one. In the future, combined studies on various sedimentary rock profiles with catchment basins are needed to determine the sources of riverine Re and Se and their relationships with OC_(petro) oxidation.

关键词： Rhenium and selenium Shale Mobility OC_(petro) Chemical weathering

Controllable nucleation and deformation of skyrmions on surface of magnetic nanotubular monolayer

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Rare Metals 2024年第7期43卷 3250-3259页

作者： Xin-Xin zhang Chen-Yu zhang Yi-Xin Xing chao Man Jiao Liu Yong Hu Department of Physics College of SciencesNortheastern UniversityShenyang 110819China School of Materials and Mineral Resources Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China

Magnetic skyrmions emerge when the energy of ferromagnetic exchange interaction promoting parallel alignment of spins enters in competition with energies favoring non-collinear alignment of spins such as Dzy aloshinskii-Moriya interaction(DMI),long-rang dipole-dipole interaction(DDI),or higher-order exchange *** perform an unbiased Monte Carlo simulation to study the DMI-based skyrmion nucleation and stabilization on the surface of magnetic nanotubular monolayer controlled by tuning constants of DDI(g) and next-nearest-neighbor antiferromagnetic exchange interaction(j') with appropriate *** g and j',the loosely distributed skyrmions initially nucleate on the surface of nanotube approaching to the magnetic field(h) direction with increasing h in the intermediate ***,the skyrmion size,shape,density,distribution and crystal structure,as well as its driven field range,are tailored by g and j'.This work demonstrates the skyrmion nucleation mechanisms in three-dimensional magnetic nanostructures with curvature effect and multiple interactions,serving as a benchmark for a guide to experimentalists for preparation of samples in magnetic skyrmion states.

关键词： Magnetic nanotube Magnetic skyrmion Dzyaloshinskii-Moriya interaction Dipole-dipole interaction Monte Carlo simulation

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

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Journal of Iron and Steel Research International 2024年第6期31卷 1367-1375页

作者： dong Feng Hong-qiang Ru Xu-dong Luo Jie-gang You Ling zhang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Institute of Advanced CeramicsSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819LiaoningChina Liaoning Institute of Science and Technology Benxi 117004LiaoningChina

In order to further promote the application of SiC refractories in modern steel metallurgy,the occurrence forms and formation mechanism of impurities in SiC crystals smelted by Acheson process were *** techniques of inductively coupled plasma-atomic emission spectrometry,X-ray diffraction,and scanning electron microscopy were combined to examine the types and occurrence forms of impurities in smelted SiC *** results showed that the main impurities in the SiC are free Si,free C,oxides(CaO·Al_(2)O_(3)·2SiO_(2),3Al_(2)O_(3)·2SiO_(2),CaO·SiO_(2) and SiO_(2))and alloy phases(Fe_(x)Si_(y),Fe_(x)Si_(y)Ti_(z) and Fe_(x)Al_(y)Si_(z)).The formation process of impurities during the smelting of SiC can be described as follows:At high temperature,the SiO_(2) and Fe,Ti related oxide impurities present in the raw materials are reduced to Si,Fe,and Ti metal *** the reduction process,the free Si,Fe_(x)Si_(y) and Fe_(x)Si_(y)Ti_(z) are precipitated from the melt during *** Si primarily exists in aggregated form within the SiC crystal,while the alloy phase is predominantly found at the interface between SiC and free Si,with Fe_(x)Si_(y)Ti_(z) embedded within *** the end of the cooling process,other impurity oxides such as Al_(2)O_(3),CaO,and some unreduced SiO_(2) solidify to form calcium-aluminum-silicate glass phases,predominantly located between SiC *** remaining C from the reaction is mainly dispersed as free C within the SiC crystal and at the interface between SiC and free Si.

关键词： Impurity element Formation mechanism Smelted SiC crystal SiC refractory Occurrence form

Interleukins in Epilepsy:Friend or Foe

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Neuroscience Bulletin 2024年第5期40卷 635-657页

作者： Yuan dong Xia zhang Ying Wang Neuropsychiatry Research Institute The Affiliated Hospital of Qingdao UniversityQingdao UniversityQingdao266000China Program in Cellular and Molecular Medicine Boston Children’s HospitalBostonMA02115USA

Epilepsy is a chronic neurological disorder with recurrent unprovoked seizures,affecting~65 million *** in patients with epilepsy and animal models suggests a contribution of neuroinflammation to epileptogenesis and the development of ***(ILs),as one of the major contributors to neuroinflammation,are intensively studied for their association and modulatory effects on ictogenesis and *** are commonly divided into pro-and anti-inflammatory cytokines and therefore are expected to be pathogenic or neuroprotective in ***,both protective and destructive effects have been reported for many *** may be due to the complex nature of ILs,and also possibly due to the different disease courses that those ILs are involved *** this review,we summarize the contributions of different ILs in those processes and provide a current overview of recent research advances,as well as preclinical and clinical studies targeting ILs in the treatment of epilepsy.

关键词： Epilepsy Interleukins Neuroinflammation

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： Liang-Liang dong Yu-Lin zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Exploring the Spatiotemporal Changes and Driving Forces of Ecosystem Services of Zhejiang Coasts,China,Under Sustainable Development Goals

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Chinese Geographical Science 2024年第4期34卷 647-661页

作者： zhang Shu SUN chao zhang Yixin HU Ming SHEN Xingru Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China donghai Academy Ningbo UniversityNingbo 315211China Zhejiang Collaborative Innovation Center&Ningbo Universities Collaborative Innovation Center for Land and Marine Spatial Utilization and Governance Research Ningbo UniversityNingbo 315211China Xiangshan High School Ningbo 315700China

Ecosystem services(ESs)refer to the continuous provisioning of ecosystem goods and services that benefit human *** recent decades,rapid urbanization has exerted significant pressure on coastal ecosystems,resulting in biodiversity and habitat loss,environmental pollution,and the depletion of natural *** response to these environmental challenges,the Sustainable Development Goals(SDGs)were *** the pressing need to address these issues,understanding the changes in ESs under the SDGs is crucial for formulating specific ecological *** this study,we first analyzed land use and cover change in the Zhejiang coasts of China during 2000–***,we investigated the spatiotemporal configuration of ESs by integrating carbon storage(CS),soil retention(SR),habitat quality(HQ)and water yield(WY)using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)*** driving mechanisms of ESs,which varied by space and time,were also explored using the Geo-detector *** results revealed that,over the past two decades:1)the Zhejiang coasts have experienced a significant increase of 2783.72 km^(2) in built-up land areas and a continuous decrease in farmland areas due to rapid urbanization;2)owing to higher precipitation,extensive vegetation cover,and reduced anthropogenic disturbances,forests emerge as a crucial land use type for maintaining ecosystem services such as HQ,CS,WY,and SR;3)ESs have generally declined across the entire Zhejiang coasts,with a significant decrease observed in the northern areas and an increase in the southern areas spatially;4)the expansion of built-up land areas emerged as the primary factor affecting ecosystem services,while the vegetation factor has been increasingly significant and is expected to become predominant in the near *** study provides insights of understanding of ecosystem service theory and emphasizing the importance of preserving biodiversity for long-term sustainable development

关键词： ecosystem services(ESs) Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model Geo-detector land use and cover change(LUCC) Zhejiang coasts China

Effect of Mn Addition and Heat Treatment on the Corrosion Behaviour of Mg-Ag-Mn Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 665-677页

作者： You Lv Yupeng zhang Xi Liu Zehua dong Xiaorong Zhou Xinxin zhang Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China Hubei Engineering Research Centre for Biomaterials and Medical Protective Materials Huazhong University of Science and TechnologyWuhan430074China Corrosion and Protection Centre Department of MaterialsThe University of ManchesterManchesterM139PLUK

The high corrosion sensitivity and the potential bio-toxicity of Mg-Ag alloys limit their wide applications for the production of implanted devices. In the present work, Mn is added into the Mg-Ag alloy to optimize its corrosion behaviour. The corrosion behaviour of Mg-Ag-Mn alloys is investigated with the underlying microstructural factors examined. The Mg-Ag alloy with 2 wt% Mn exhibits the highest corrosion resistance after post-casting heat treatment at 440 ℃. The addition of Mn results in α-Mn phase with the incorporation of Fe, which suppresses the cathodic activity of impurity Fe. Further, heat treatment of the cast alloys homogenizes the distribution of Ag and promotes the precipitation of α-Mn phase. The former removes Ag segregations as potential cathodes;the latter promotes a more uniform distribution of cathodes and, therefore, prevents localized corrosion.

关键词： Mg-Ag alloy Mn addition Post-casting heat treatment Cathodic activity Corrosion mechanism

Transmissive reconfigurable metasurface enabling independent control of active and passive modules through weak coupling

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Photonics Research 2024年第7期12卷 1449-1456页

作者： KUN XUE HENG WEI CILEI zhang YONGHAO zhang HAOLIANG SUN SHAOHUA dong Peng Cheng Laboratory Shenzhen 518055China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore State Key Laboratory of Radio Frequency Heterogeneous Integration College of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China

Metasurfaces have demonstrated rich electromagnetic control capabilities and degrees of freedom in past years. As is well known, for passive metasurfaces, their functionalities cannot be further expanded accordingly once prototypes are established. Therefore, reconfigurable metasurfaces, utilizing active devices to replace geometric changes in passive structures, have received widespread attention, especially with the development of wireless communication recently. In reconfigurable metasurfaces, artificial meta-atoms are composed of active devices and passive structures combined together. However, these two modules are usually utilized as a whole due to the tight coupling of the active devices and the passive structures, which results in passive structures not receiving sufficient attention and being utilized as independent degrees of freedom. In this article, we propose the concept of weakly coupled reconfigurable metasurfaces in transmissive systems, enabling independent control of active and passive modules through weak coupling. As the proof of concept, a simple weakly coupled system is proposed, which can realize the transmission wavefront engineering through the geometric changes of meta-structures in passive mode, while achieving switching between transmission and reflection states in active mode, respectively. Our exploration lies in making use of the physical structure, which is easily neglected in traditional reconfigurable metasurface design, emphasizing the collaborative work of active and passive modules, exploring more available variables within the same aperture, and providing a potential solution for balancing functionality and resource consumption in practical applications.

关键词： modules coupling weakly

A state-of-the-art review of the development of self-healing concrete for resilient infrastructure

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 151-169页

作者： dong LU Xi JIANG Yao zhang Shaowei zhang Guoyang LU Zhen LENG Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Laboratory of Fire Safety School of Safety Engineering and Emergency ManagementShijiazhuang Tiedao UniversityShijiazhuang 050043China Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China

The brittleness of cement composites makes cracks almost inevitable,producing a serious limitation on the lifespan,resilience,and safety of concrete *** address this brittleness,self-healing concrete has been developed for regaining its mechanical and durability properties after becoming cracked,thereby promising sustainable development of concrete *** paper provides a comprehensive review of the latest developments in self-healing *** begins by summarizing the methods used to evaluate the self-healing efficiency of ***,it compares strategies for achieving healing *** then discusses the typical approaches for developing self-healing ***,critical insights are proposed to guide future studies on the development of novel self-healing *** review will be useful for researchers and practitioners interested in the field of self-healing concrete and its potential to improve the durability,resilience,and safety of concrete infrastructure.

关键词： resilient infrastructure sustainable concrete self-healing cracks