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Recent Advances on Polyoxometalate-Based Ion-Conducting Electrolytes for Energy-Related Devices

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Energy & Environmental Materials 2023年第2期6卷 262-274页

作者： dongming Cheng Ke li Hongying Zang Jiajia Chen Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education at Universities of Jilin Province Faculty of ChemistryNortheast Normal UniversityChangchun 130024China State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringCollaborative Innovation Centre of Chemistry for Energy MaterialsXiamen UniversityXiamen 361005China

Solid-state electrolytes have attracted considerable attention in new energyrelated devices due to their high safety and broad application ***(POMs)are a kind of molecular-level cluster compounds with unique *** recent years,owing to their abundant physicochemical properties(including high ionic conductivity and reversible redox activity),POMs have shown great potential in becoming a new generation of solid-state *** this review,an overview is investigated about how POMs have evolved as ion-conducting materials from basic research to novel solid-state electrolytes in energy ***,some expressive POM-based ion-conducting materials in recent years are introduced and classified,mainly inspecting their structural and functional *** that,it is further focused on the application of these ionconducting electrolytes in the fields of proton exchange membranes,supercapacitors,and ion *** addition,some properties of POMs(such as inherent dimension,capable of forming stable hydrogen bonds,and reversible bonding to water molecules)enable these functional POM-based electrolytes to be employed in innovative applications such as ion selection,humidity sensing,and smart ***,some fundamental recommendations are given on the current opportunities and challenges of POM-based ion-conducting electrolytes.

关键词： energy devices ion conduction polyoxometalates solid-state electrolytes

Surface morphologies of Mg-Gd alloy particle during its reactions with O_(2) and Teflon

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Defence Technology（防务技术） 2024年第3期33卷 209-221页

作者： Yifan li Hongtao Yang Aifeng Jiang dongming Song Yanchun li Department of Chemical Engineering Nanjing University of Science and TechnologyNanjing 210097China Xi'an Modern Chemistry Research Institute Xi'an 710065China Southwest Technology and Engineering Research Institute Chongqing 400039China

Mg-Gd alloy particle has exhibited its unique combustion properties as the fuel of Mg/Teflon/Viton(MTV).Mg-Gd alloy/Teflon/Viton(MGTV)could burn at lower ambient pressure than *** further investigate the reaction of MGTV in air,it was investigated via thermo gravity-differential scanning calorimetry(TG-DSC).Meanwhile,the morphologies and element distributions on the alloy surface during the reaction of MGTV in air were investigated via scanning electronic microscope-mapping-electronic differential ***,a similar experimental protocol on the Mg-Gd alloy particle during oxidation was also *** results showed that owning to a protective oxide shell,the onset oxidation temperature of Mg-Gd alloy is higher than ***,the onset oxidation temperature of the exceeded Mg-Gd alloy in MGTV is significantly lower than that of the exceeded Mg in *** was due to the existence of GdOF,which could significantly lower the oxidation temperature of the exceeded ***,a possible reaction mechanism was *** fascinating oxidation properties of Mg-Gd alloy suggested its promising applications in energetic materials.

关键词： Mg-Gd alloy Energetic materials Morphology EDS GdOF

Failure responses of rock tunnel faces during excavation through the fault-fracture zone

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Underground Space 2023年第3期10卷 166-181页

作者： Zeyu li Hongwei Huang Mingliang Zhou dongming Zhang Department of Geotechnical Engineering Tongji UniversitySiping Road 1239Shanghai 200092China

It is essential to cast light on the construction risks in tunnel excavations through the fault-fracture zone(FFZ).This study adopts the material point method(MPM)to simulate the failure responses of a rock tunnel face during excavation through the FFZ.A numerical study was conducted to compare a physical model test and validate the feasibility of using the MPM in simulating tunnel face *** hundred ninety numerical simulation cases were constructed to represent a rock tunnel excavation project with different site *** simulation results suggest that the cohesion and the friction angle significantly influence failure *** tunnel cover depth can magnify the failure responses,and the FFZ thickness significantly affects the mobilized rock mass volume when the FFZ consists of a weak rock *** numerical simulation results suggest three deformation patterns:face bulge,partial failure,and slide *** failure responses can be characterized by stress arch,slip surface,angle of reposing,and influence *** insights suggested by the face failure responses during excavation through the FFZ can aid field engineers in determining the scope of possible damage,and in establishing emergency measures to minimize losses if such failure occurs.

关键词： Tunnel face failure Rock tunnel excavation Large deformation Fracture fault zone Material point method

Avian hippocampus:Recent advances in anatomy and physiological functions

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Avian Research 2024年第4期15卷 482-495页

作者： Juyong li Jing-An liu limin Wang dongming li Hebei Key Laboratory of Animal Physiology Biochemistry and Molecular BiologyCollege of Life SciencesHebei Normal UniversityShijiazhuang050024China Hebei Collaborative Innovation Center for Eco-Environment Hebei Normal UniversityShijiazhuang050024China

The avian hippocampus,akin to its mammalian counterpart,plays a critical role in cognitive and physiological processes despite notable structural *** thought to be less developed,recent studies over the past two decades have revealed it as a complex brain region essential for diverse functions in both laboratory and free-living *** review synthesizes current knowledge on the avian hippocampus’organization,functionality,and neurophysiological *** first examine its anatomical structure and neuronal connectivity,comparing it with the mammalian *** then highlight how its volume,neuronal density,and neurogenesis support spatial memory and navigation,influencing behaviors such as migration,food storing,brood parasitism,and *** spatial functions,the avian hippocampus mediates emotion and stress physiology through interactions with the endocrine system,particularly via glucocorticoid *** also influences spatial memory through sex hormones,especially estradiol,with local estrogen production through aromatase activity enhancing memory and ***,the avian hippocampus serves as a central neural hub,integrating sensory information with internal states to facilitate essential behaviors and responses to external environmental *** review underscores the progress made in understanding this brain structure’s roles,highlighting conserved neurophysiological functions across vertebrate taxa.

关键词： Emotional behavior Endocrine system Hippocampal anatomy Spatial memory Stress-related behavior

Impacts of practical channel impairments on the downlink spectral efficiency of large-scale distributed antenna systems

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Science China(Information Sciences) 2019年第2期62卷 146-159页

作者： Jiamin li dongming WANG Pengcheng ZHU Xiaohu YOU National Mobile Communications Research Laboratory Southeast University

Channel impairments are major limiting factors in the performance of large-scale antenna systems. In this paper, we analyze the impacts of practical channel impairments caused by pilot contamination,Doppler shift, and phase noise on the downlink spectral efficiency of large-scale distributed antenna systems(L-DASs) with maximum ratio transmission(MRT) and zero-forcing(ZF) beamforming, in which per user power normalization is considered. Using a joint channel model that allows study of the simultaneous impacts of these channel impairments, we derive accurate and tractable closed-form approximations for the ergodic achievable downlink rate, thereby enabling spectral efficiency analysis of L-DASs and an efficient evaluation of the impacts of the channel impairments. It is shown that channel impairments reduce the downlink spectral efficiency and have a significant impact on ZF beamforming. The asymptotic user rate limit is also determined, from which we analyze the asymptotic performance of L-DASs with channel impairments. The analytical results show that MRT and ZF beamforming achieve the same asymptotic performance limit even with channel impairments. It is also found that the use of a large-scale antenna array at the base station sides can weaken the impacts of channel impairments.

关键词： Doppler shift phase noise large-scale distributed antenna systems spectral efficiency pilot contamination

Foreword to the Special Issue

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Journal of Systems Science & Complexity 2019年第1期32卷 1-2页

作者： GAO Xiao-Shan li Hongbo WANG dongming Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science University of Chinese Academy of Sciences Chinese Academy of Sciences LMIB–SKLSDE–School of Mathematics and Systems Science/Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang University Centre National de la Recherche Scientifique

On May 12,2019 we shall celebrate the centenary birthday of the late Professor Wu Wen-Tsun (1919-2017),one of the most famous and influential mathematicians in *** made foundational contributions to the field of topology and established Mathematics Mechanization as a *** devoted himself to an academic career of more than six decades with leadership and extensive activities of research and education across mathematics to computer science and artificial *** scope of his research spans from algebraic topology, differential topology,and algebraic geometry to automated reasoning,symbolic computation, and game theory,and to the history of *** early work in topology was a major breakthrough,leading to well-known and now classical results including the characteristic class and formulas named after *** the late 1970s,he pioneered the research of Mathematics Mechanization through his invention of the "Wu method",which revolutionized the field of automated reasoning.

关键词： shall celebrate centenary birthday established Mathematics

Compound-mode crack propagation law of PMMA semicirculararch roadway specimens under impact loading

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International Journal of Coal Science & Technology 2021年第6期8卷 1302-1315页

作者： Chengxiao li dongming Guo Yuantong Zhang Chen An School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China

An underground roadway usually contains defects of various types,and when the roadway is subjected to external loading,the locations of those defects influence the roadway by differing *** this study,to study how the locations of defects affect crack propagation in a roadway,specimens with tunnel-type voids were made using polymethyl methacrylate,and the stress wave produced by a bullet impacting an incident rod was used as the impact ***,the variations in crack speed,displacement,and dynamic stress intensity factor during crack propagation were obtained using an experimental system of digital laser dynamic caustics,and the commercial software ABAQUS was used for numerical *** the experiments and numerical simulations,the crack propagation path was verified and the impact fracture behavior of a semicircular-arch roadway with different defect positions was *** results show that when the pre-fabricated crack is on the central axis of the sample,the crack propagation is purely mode I;when the pre-fabricated crack is 5 mm from the central axis,the crack propagation alternates between mode I and a mixture of modes I and II;when the pre-fabricated crack is at the edge of the semicircular-arch roadway,the crack propagation follows the I-II mixed mode.

关键词： Defect location Dynamic caustics Polymethyl methacrylate ABAQUS Semicircular-arch roadway

Microstructural and thermal properties of coal measure sandstone subjected to high temperatures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2909-2921页

作者： Weijing Xiao dongming Zhang Shujian li Mingyang Wu School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang330013China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China Yunnan Phosphate Chemical Group Co. Ltd.Kunming650600China National Engineering and Technology Research Center for Development and Utilization of Phosphate Resources Kunming650600China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

To study the microscopic structure,thermal and mechanical properties of sandstones under the influence of temperature,coal measure sandstones from Southwest China are adopted as the research object to carry out high-temperature tests at 25℃-1000℃.The microscopic images of sandstone after thermal treatment are obtained by means of polarizing microscopy and scanning electron microscopy(SEM).Based on thermogravimetric(TG)analysis and differential scanning calorimetric(DSC)analysis,the model function of coal measure sandstone is explored through thermal analysis kinetics(TAK)theory,and the kinetic parameters of thermal decomposition and the thermal decomposition reaction rate of rock are *** the uniaxial compression experiments,the stress‒strain curves and strength characteristics of sandstone under the influence of temperature are *** results show that the temperature has a significant effect on the microstructure,mineral composition and mechanical properties of *** particular,when the temperature exceeds 400℃,the thermal fracture phenomenon of rock is obvious,the activity of activated molecules is significantly enhanced,and the kinetic phenomenon of the thermal decomposition reaction of rock appears *** mechanical properties of rock are weakened under the influence of rock thermal fracture and mineral thermal *** research results can provide a reference for the analysis of surrounding rock stability and the control of disasters caused by thermal damage in areas such as underground coal gasification(UCG)channels and rock masses subjected to mine fires.

关键词： Rock mechanics Coal measure sandstone Micromorphology Thermal damage

Phase component and microstructure of laser-sintered Mg-Ni alloys

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Rare Metals 2008年第4期27卷 400-404页

作者： SI Tingzhi li Yongtao liU dongming ZHANG Qing＇an School of Materials Science and Engineering Anhui University of Technology Maanshan 243002 China

The Mg-Ni hydrogen storage alloys were prepared using the laser sintering technology. The effects of laser sintering power on the phase component and the weight loss of Mg element for the Mg-Ni alloys were investigated. The samples P1, P2 and P3 consisted of five phases： Mg2Ni, MgNi2, Mg, Ni and MgO. The weight loss of Mg element remarkably increased at 1200 W. The addition of extra Mg significantly promoted the reaction between Mg and Ni. Mg2Ni, MgNi2, and a small amount of Ni and MgO phases were present in the samples PM （pestie milling） and BM （ball milling）. The sample PM has a homogeneous microstructure, and the contents of Mg2Ni and MgNi2 were approximately consistent with those of the Mg-Ni alloy under the equilibrium conditions. The maximum hydrogen storage capacity of the sample BM was 1.72 wt.% and the sample can be activated easily at 573 K （only 3 activation cycles）.

关键词： hydrogen storage alloys phase structure laser sintering hydrogen storage property