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Highly reversible Zn anode enabled by anticatalytic carbon layer with suppressed hydrogen evolution

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Rare Metals 2024年第7期43卷 3044-3054页

作者： Wen-Duo Zhang Chuang Sun yu-Xuan Zhu feng Gao Chao Lai School of Chemistry and Materials Science Jiangsu Normal University

Aqueous zinc-ion batteries（AZIBs） have emerged as a promising high-efficiency energy storage system due to the high energy density,low-cost and environmental ***,the practical application of AZIBs is severely restricted by the challenges faced by the Zn anode,which include uncontrollable dendrite growth,corrosion and hydrogen evolution ***,a simple and convenient physical vapor deposition（PVD）method is reported for fabricating uniform graphite as a protection layer on the surface of Zn *** high conductivity graphite layer on Zn anode（denoted as Zn@C） not only benefits the uniform distribution of the electric field,but also provides numerous Zn nucleation sites to regulate and navigate Zn-ion stripping/plating ***,the graphite layer with a poor catalytic activity endows the Zn@C anode with a highly suppressed hydrogen ***,a hydrogen and dendrite free anode is achieved with artificial anticatalytic carbon layer on Zn anode,exhibiting a high reversibility and excellent cycling stability over 2600 h at the current density of 5 mA·cm-2with a capacity of 2.5 mAh·cm-2and longtime cycling stability for assembled full *** work strategically designs the properties of the artificial interface layer to effectively address various challenges simultaneously,which presents insights for the future development of high-performance rechargeable AZIBs.

关键词： Zn metal anode Artificial anticatalytic layer Hydrogen suppression Dendrite free

Enhancement and Removal of PM_(2.5)by Cold and Warm Air Masses Accompanying Certain Synoptic Weather Systems across Hangzhou,China during 2014-2020

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Journal of Meteorological Research 2024年第3期38卷 620-634页

作者： Bu yu feng CHEN Hanqing KANG Bin ZHU Hongnian LIU Hangzhou Meteorological Bureau Hangzhou310051China Hangzhou International Urbanology Research Center for Urban Governance Studies Hangzhou311121China Zhejiang Institute of Meteorological Sciences Hangzhou310008China Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing210044China School of Atmospheric Sciences Nanjing UniversityNanjing210023China

Local air pollution is strongly affected by synoptic weather systems,such as fronts,troughs,low-altitude vortices,or high-altitude ***,few studies have analyzed the meteorological properties of cold or warm air masses associated to these systems and their impact on local air *** this study,hourly observations of fine particulate matter(diameter of up to 2.5µm,i.e.,PM_(2.5)),wind(V),temperature(T),pressure(P),and precipitation(R),acquired in Hangzhou in 2014-2020,were *** this analysis,weather patterns were categorized into 27 types;89 and 94 cases illustrating the passage of warm and cold air masses over Hangzhou were identified,respectively;the influence of air mass temperature,wind speed,and wind direction on PM_(2.5) concentrations and local accumulation or removal was *** main results are as follows.(1)Pollution events occurred more frequently for cold than for warm air masses,but average pollutant concentration was lower for cold air masses;(2)48%of the cold air mass cases corresponded to PM_(2.5) decreases and 52%to PM_(2.5) increases,with strong cold air masses(ΔT_(24h)>4°C;∣V∣_(average)>4 m s^(−1))markedly reducing local pollution,but weak cold air masses(ΔT24h4°C)reduced the PM_(2.5) concentration whereas weaker winds(∣V∣_(average)<2 m s^(−1))increased it;and(4)PM_(2.5) concentration decreased sharply within 4 h after the passage of strong cold air masses,but more gradually within 14 h after the passage of strong warm air *** results considerably improve the current understanding of the influence of cold and warm air masses on local pollution patterns.

关键词： weather type air mass enhancement removal meteorological condition

Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron

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China Foundry 2024年第1期21卷 91-100页

作者： De-quan Shi Ze-yu Liu Gui-li Gao Yi-cheng feng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Chemical Engineering Harbin University of Science&TechnologyHarbin 150040China School of Mechanical and Energy Engineering Shanghai Technical Institute of Electronics and InformationShanghai 201411China

Thermal analysis plays a key role in the online inspection of molten iron *** solidification process of molten iron can be reflected by thermal analysis curves,and silicon is one of important elements affecting the solidification of molten *** this study,FeSi75 was added in one chamber of the dual-chamber sample cup,and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were *** results show that with the increase of FeSi75,the start temperature of austenite formation TALfirstly decreases and then increases,but the start temperature of eutectic growth TSEF,the lowest eutectic temperature TEU,temperature at maximum eutectic reaction rate TEM,and highest eutectic temperature TERkeep always an *** temperature at final solidification point TEShas little *** FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation,and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher *** to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.%FeSi75 additive in one chamber,the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these *** time differenceΔtERcorresponding to the highest eutectic temperature TERhas a closer relationship with the vermiculating rate,and a parabolic regression curve between the time differenceΔtERand vermiculating rateηhas been obtained within the range of 65%to 95%,which is suitable for the qualified melt.

关键词： FeSi75 additive characteristic value vermiculating rate thermal analysis compacted graphite iron

Stage separation of recoverable liquid launch vehicle by using moving pulsating ball analogue for propellant sloshing

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Chinese Journal of Aeronautics 2024年第2期37卷 360-370页

作者： yu LU Baozeng yuE Bailong HAO Bole MA feng LIU yuanyuan CHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

In the process of stage separation of recoverable liquid launch vehicles,because of the large amount of residual fuel in the storage tanks,the influence of liquid sloshing on separation safety must be *** calculation simplicity and operation practicability,the Moving Pulsating Ball Model(MPBM)of large amplitude liquid sloshing is introduced into the calculation of launch vehicle stage *** the dynamic equation of the model with the energy relationship during"breathing movement",the formula calculating the force of liquid on the rigid body is *** with the calculations of commercial CFD calculation software,the accuracy of MPBM model is ***,all the external forces and moments are applied to the rigid body of the stages,so that the translational and rotational dynamic equations of the stages are obtained *** to the relative position of the two stages,the geometric shape of the interstage section and the engine of the second stage,the minimum clearance in the separation process can be decided to guarantee that the separation process is safe.

关键词： Moving Pulsating Ball Model(MPBM) Dynamics of stage separation Large amplitude sloshing Recoverable liquid launch vehicle Flight dynamics

Layered metastructure containing freely-designed local resonators for wave attenuation

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Defence Technology（防务技术） 2024年第2期32卷 23-31页

作者： yu Li Huguang He Jiang feng Hailong Chen fengnian Jin Hualin Fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007China Rocket Force University of Engineering Xi'an 710025China Henan International Joint Laboratory of Dynamics of Impact and Disaster of Engineering Structures Department of Civil EngineeringNanyang Institute of TechnologyNanyang 473004China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety and Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China

Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical *** metastructure is composed of periodic rubber layers and concrete layers embedded with three-dimensional resonators,which can be freely designed with multi local resonant frequencies to attenuate vibrations at required frequencies and widen the attenuation *** metastructure can also effectively attenuate seismic *** with layered rubber-based structures,the metastructure has more excellent wave attenuation effects with greater attenuation and wider bandgap.

关键词： Layered metastructure Local resonator Wave attenuation

Molecular Dynamics Simulation Studies on the Micromorphology and Proton Transport of Nafion/Ti_(3)C_(2)T_(x) Composite Membrane

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Chinese Journal of Polymer Science 2024年第3期42卷 373-387,I0009页

作者： Zhi-yue Han Su-Peng Pei Chun-Yang yu Yong-feng Zhou School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China School of Chemistry&Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgingShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Green and High-end Utilization of Salt Lake Resources Chinese Academy of SciencesXining 810008China

The perfluorosulfonic acid(PFSA) membrane doped with two-dimensional conductive filler Ti_(3)C_(2)T_(x) is a fuel cell proton exchange membrane with high application potential. Experimental studies showed that the proton conductivity of Nafion/Ti_(3)C_(2)T_(x) composite membrane is improved significantly compared with that in pure Nafion. However, the microscopic mechanism of doping on the enhancement of membrane performance is remain unclear now. In this work, molecular dynamics simulation was used to investigate the microscopic morphology and proton transport behaviors of Nafion/Ti_(3)C_(2)T_(x) composite membrane at the molecular level. The results shown that there were significant differences about the diffusion kinetics of water molecules and hydroxium ions in Nafion/Ti_(3)C_(2)T_(x) at low and high hydration levels in the nanoscale *** the increase of water content, Ti_(3)C_(2)T_(x) in membrane was gradually surrounded by ambient water molecules to form a hydration layer, and forming a relatively continuous proton transport channel between Nafion polymer and Ti_(3)C_(2)T_(x) monomer. The continuous proton transport channel could increase the number of binding sites of proton and thus achieving high proton conductivity and high mobility of water molecules at higher hydration level. The current work can provide a theoretical guidance for designing new type of Nafion composite membranes.

关键词： Nafion/Ti_(3)C_(2)T_(x)composite membrane Proton transport Molecular dynamics simulation

Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface

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International Journal of Extreme Manufacturing 2024年第2期6卷 449-467页

作者： Zhiwei Li Jianfu Zhang Zhongpeng Zheng Pingfa feng Dingwen yu Jianjian Wang State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipments and Control Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Division of Advanced Manufacturing Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055People’s Republic of China

High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon ***,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing *** study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect *** conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving *** tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material *** to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling *** one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of ***,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process ***,surface texturing tests are performed on copper to verify the efficacy of *** micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on *** with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 *** experimental results also verify the accuracy of the developed surface generation model of ***,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed.

关键词： metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation

Exploration of pathogenic microorganism within the small intestine of necrotizing enterocolitis

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World Journal of Pediatrics 2024年第2期20卷 165-172页

作者： Yan Wang Kun Jiang qiao Xia Xia Kang Shan Wang Ji-Hong yu Wen-feng Ni Xiao-qin qi Ying-Na Zhang Jin-Bao Han Gang Liu Lei Hou Zhi-Chun feng Liu-Ming Huang Clinical Biobank Center Medical Innovation Research Division of ChinesePLA General HospitalBeijingChina Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Senior Department of Pediatrics The Seventh Medical Center of PLA General HospitalBeijing 100700China Department of Neurology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Emergency Center National Center for Children's HealthBeijing Children's HospitalCapital Medical UniversityBeijing 100045China

Background Necrotizing enterocolitis(NEC)is the most common severe gastrointestinal emergency in *** designed this study to identify the pathogenic microorganisms of NEC in the microbiota of the small intestine of *** Using the 16S ribosomal DNA(rDNA)sequencing method,we compared and analyzed the structure and diversity of microbiotas in the intestinal feces of different groups of neonates:patients undergoing jejunostomy to treat NEC(NP group),neonates undergoing jejunostomy to treat other conditions(NN group),and neonates with NEC undergoing conservative treatment(NC group).We took intestinal feces and saliva samples from patients at different time *** The beta diversities of the NP,NN,and NC groups were all *** comparing the beta diversities between different time points in the NP group,we found similar beta diversities at time points El to E3 but significant differences between the E2-E3 and E4 time points:the abundances of Klebsiella and Enterococcus(Proteobacteria)were higher at the E1-E3 time points;the abundance of Escherichia-Shigella(Proteobacteria)increased at the E2 time point,and the abundance of Klebsiella decreased significantly,whereas that of Streptococcus increased significantly at the E4 time *** Our results suggest that the pathological changes of intestinal necrosis in the small intestine of infants with NEC are not directly caused by excessive proliferation of pathogenic bacteria in the small *** sources of microbiota in the small intestine of neonates,especially in premature infants,may be affected by multiple factors.

关键词： Microbiota Necrotizing enterocolitis-Small intestine 16S rDNA

Metallic Sb-stabilized porous silicon with stable SEI and high electron/ion conductivity boosting lithium-ion storage performance

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Rare Metals 2024年第9期43卷 4234-4242页

作者： Jia-Guo Deng Hao-qin feng yu-Long Xu Si-Guang Guo Jian-Ping Li kai-Fu Huo Ji-Jiang Fu Biao Gao Pual-K.Chu The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and Technology Wuhan National Laboratory for Optoelectronics (WNLO) School of Optical and Electronic InformationHuazhong University of Science and Technology Department of Physics Department of Materials Science & Engineeringand Department of Biomedical EngineeringCity University of Hong Kong

Silicon （Si） has mild discharge potential and high theoretical capacity,making it a highly desirable material for lithium-ion batteries （LIBs）.Nevertheless,the excessive volume expansion,poor ion/electron conductiv ity and unstable solid electrolyte interface （SEI） hinde practical application to ***,the metallic antimony（Sb） stabilized porous Si （SiDSb） composite was prepared by magnesiothermic reduction of Sb2O3and Mg2Si and chemical etching to remove the by-product of *** highly conductive Sb nanodots embedded in the Si liga ments promote not only the formation of conductive and stable LiF-rich SEI,but also the electron/ion transpor ability of *** to the outstanding bulk/interface stability,excellent conductivity,as well as ideal porous structure,the SiDSb electrode demonstrates a capacity of820 mAh·g-1after undergoing 320 turns at 1000 mA·***,it exhibits a stable capacity of 675 m Ah·g-1when tested at a higher current density of 5000 m A·*** results reveal a viable solution to solve three problems at the same time,namely the poor conductivity,inferior SEI and excessive volume expansion of Si,boding well for the design of Si-based materials for high-energy LIBs.

关键词： Anodes Antimony Lithium-ion batteries Silicon Solid electrolyte interphase