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Recent Progress in Carbon-based Materials of Non-Noble Metal Catalysts for ORR in Acidic Environment

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 885-899页

作者： jie lian Jin-Yu Zhao Xiao-Min Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Shanxi Key Laboratory of New Energy Materials and Devices Taiyuan University of TechnologyTaiyuan 030024China

Proton exchange membrane fuel cell(PEMFC)has important implications for the success of clean transportation in the *** of the key factors affecting the cost and performance of PEMFC is the cathode electrocatalyst for the oxygen reduction reaction(ORR)to overcome sluggish kinetics and instability in an acidic *** an essential component of the electrocatalyst,the support material largely determines the activity,mass transfer,charge transfer,and durability of the ***,the support material plays a critical role in the overall performance of the *** materials are widely used as electrocatalyst supports because of their high porosity,conductivity,chemical stability,and tunable ***,some new carbon-based materials with excellent structure have been introduced,such as carbon nanotubes,carbon nanowires,graphene,metal-organic framework(MOF)-derived carbon,and biomass-derived carbon *** with a variety of strategies,such as controllable construction of porous structures and surface defects,proper doping heteroatoms,the ingenious design of model electrocatalysts,and predictive theoretical calculation,a new reliable path was provided for further improving the performance of electrocatalysts and exploring the catalytic *** on the topic of carbon-based materials for ORR in acidic medium,this review summarizes the up-to-date progress and breakthroughs,highlights the factors affecting the catalytic activity and stability of ORR electrocatalysts in acids,and discusses their future application and development.

关键词： Carbon-based materials Non-noble metal electrocatalysts Acidic environment Oxygen reduction reaction Proton exchange membrane fuel cell

Robust H-infinity integral sliding mode control for a class of uncertain switched nonlinear systems

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控制理论与应用（英文版） 2010年第4期8卷 521-526页

作者： jie lian Jun ZHAO Faculty of Electronic Information and Electrical Engineering Dalian University of Technology Dalian Liaoning 116024 China Key Laboratory of Integrated Automation of Process Industry Northeastern University Shenyang Liaoning 110004 China

This paper develops a new method to deal with the robust H-infinity control problem for a class of uncertain switched nonlinear systems by using integral sliding mode control.A robust H-infinity integral sliding surface is constructed such that the sliding mode is robust stable with a prescribed disturbance attenuation level γ for a class of switching signals with average dwell ***,variable structure controllers are designed to maintain the state of switched system on the sliding surface from the initial time.A numerical example is given to illustrate the effectiveness of the proposed method.

关键词： Uncertain switched nonlinear systems Integral siding mode control Average dwell time

Vortex Evolution Behavior in Self-Assembly of Flow Units in Metallic Glasses

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Acta Mechanica Solida Sinica 2023年第5期36卷 603-611页

作者： jie lian Ruyue Song Yan Chen Lanhong Dai State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Shear banding in amorphous metals originates from the activation and percolation of flow *** uncover the self-assembly dynamics of flow units in metallic glasses,a rectangular sample with two flow units embedded in the matrix undergoing simple shearing was analyzed using finite element *** vortex evolution behavior,including activation,growth,and collapse during the self-assembly of flow units,was *** was found that the formation of a mature vortex indicates the onset of yielding,and the collapse of the vortex represents the percolation of flow units or shear *** effects of initial free volume distribution and the distance between flow units on vortex behavior were also *** the initial free volume concentration within flow units or the matrix leads to a gentler vortex evolution process and better homogeneous *** shape of vortex tends to be"flatter"with the increase in flow units'spacing,and the optimal spacing was found to maximize the strength of the material.

关键词： Vortex Free volume Self-assembly Flow units Metallic glasses

Correlation analysis between underwater noise and Liutex for DTMB4119 propeller

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Journal of Hydrodynamics 2022年第4期34卷 585-595页

作者： lian-jie Yu Jian-wei Wu De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Wuhan Second Ship Design and Research Institute Wuhan 430205China

Propeller is an important equipment of ocean *** has characteristics of complex geometry and periodic vortex shed,which means high research *** paper takes DTMB419 propeller as the research object.A detailed study is conducted on the wake vortices in non-cavitation state and cavitation *** vortex identification methods are used to compare the vortices capture effects from downstream sections and three-dimensional *** results show that,the third-generation vortex identification technologyΩ_(R)shows obvious *** the same time,FW-H equation is used to predict propeller noise,and the relationship between nonlinear sound source distribution and vortices distribution is *** is found that the distribution of Lighthill tensor is consistent withΩ_(R),which proves the advantages and potential of third-generation vortex identification technology from acoustic perspective.

关键词： Third-generation vortex DTMB4119 propeller cavitation FW-H formulation

Low Temperature Superplasticity of 40Cr Steel

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Journal of Iron and Steel Research International 2004年第4期11卷 56-58页

作者： XU Xiao-jing SHI lian-jie Jiangsu University

The low temperature superplastic characteristics of commercial 40 Cr steel,which was subjected to water quenching three times and subsequent high temperature tempering,were *** results show that the 40 Cr steel has a grain size of 5-10μm,and exhibits an elongation of 254 %,a flow stress of 108.1 MPa,a strain rate sensitivity m-value of 0.221 at the temperature of 650 ℃ and the initial strain rate of 3.16×10-4 s-1.

关键词： superplasticity 40Cr steel low temperature microstructure

Succinylation modification:a potential therapeutic target in stroke

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Neural Regeneration Research 2024年第4期19卷 781-787页

作者： jie lian Wenwu Liu Qin Hu Xiaohua Zhang Department of Neurosurgery Ren Ji HospitalShanghai Jiao Tong University School of Medicine Department of Diving and Hyperbaric Medicine Naval Medical CenterNaval Medical University

Stroke is a leading cause of mortality and disability *** cell death triggered by the compromised supply of blood oxygen and glucose is one of the major pathophysiology of strokeinduced brain *** mitochondrial energy metabolism is observed minutes after stroke and is closely associated with the progression of ***,a new type of posttranslational modification,known as lysine succinylation,has been recognized to play a significant role in mitochondrial energy metabolism after ***,the role of succinylation modification in cell metabolism after stroke and its regulation are not well *** aimed to review the effects of succinylation on energy metabolism,reactive oxygen species generation,and neuroinflammation,as well as Sirtuin 5 mediated desuccinylation after *** also highlight the potential of targeting succinylation/desuccinylation as a promising strategy for the treatment of *** succinylation level is dynamically regulated by the nonenzymatic or enzymatic transfer of a succinyl group to a protein on lysine residues and the removal of succinyl catalyzed by *** evidence has suggested that succinylation can regulate the metabolic pathway through modulating the activity or stability of metabolic ***,especially Sirtuin 5,are characterized for their desuccinylation activity and have been recognized as a critical regulator of metabolism through desuccinylating numerous metabolic *** between succinylation and desuccinylation has been implicated in the pathophysiology of *** agents that enhance the activity of Sirtuin 5 have been employed to promote desuccinylation and improve mitochondrial metabolism,and neuroprotective effects of these agents have been observed in experimental stroke ***,their therapeutic efficacy in stroke patients should be validated.

关键词： mitochondria metabolism neuroprotection sirtuin 5 stroke succinylation modification

Effect of the lenticles on moisture migration in capillary zone of tailings dam

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1036-1045页

作者： Di Liu Min-jie lian Cai-wu Lu Wen Zhang College of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Institute of Mining System Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Sinosteel Mining Co. Ltd.Beijing 100080China School of Resource Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Small-particle interlayers(lenticles)show some characteristic hydraulic properties and can affect the movement of unsaturated *** this study,we developed a novel online capillary-water-absorption monitoring device and conducted three groups of comparison tests to simulate lenticle positions and thicknesses with respect to the capillary *** results show that the characteristic wetting front exhibits a fast rise in the early stage,a slow rise in the middle stage,and stability in the later *** motion of the capillary water in the lenticle is mainly transversal,with the upward curve being"flat,"and the longer is"flat,"the longer is the time needed for the water to *** interlayer can form a capillary stagnation zone with moisture content close to *** high interlayer may form a discontinuous corrugated capillary ***,when the wetting front reaches the"coarse-grain(lower)-fine-grain(upper)"interface,the"anti-capillary barrier effect"results in more moisture in the upper ***,when the wetting front of the capillary water reaches the"fine-grain(upper)-coarse-grain(lower)"interface,the"capillary barrier effect"causes the moisture content of the upper tailings to decreases sharply because of the horizontal movement of the water in the fine *** is clear that the presence of lenticles can retard the rise of capillary water by storing water.

关键词： tailings lenticle moisture migration capillary retarding effect microcosmic mechanism

A Review of In‑Situ Techniques for Probing Active Sites and Mechanisms of Electrocatalytic Oxygen Reduction Reactions

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Nano-Micro Letters 2023年第2期15卷 61-113页

作者： Jinyu Zhao jie lian Zhenxin Zhao Xiaomin Wang Jiujun Zhang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024People’s Republic of China Institute for Sustainable Energy/College of Sciences Shanghai UniversityShanghai 200444People’s Republic of China

Electrocatalytic oxygen reduction reaction(ORR)is one of the most important reactions in electrochemical energy technologies such as fuel cells and metal–O2/air batteries,***,the essential catalysts to overcome its slow reaction kinetic always undergo a complex dynamic evolution in the actual catalytic process,and the concomitant intermediates and catalytic products also occur continuous conversion and *** makes them difficult to be accurately captured,making the identification of ORR active sites and the elucidation of ORR mechanisms ***,it is necessary to use extensive in-situ characterization techniques to proceed the real-time monitoring of the catalyst structure and the evolution state of intermediates and products during *** work reviews the major advances in the use of various in-situ techniques to characterize the catalytic processes of various ***,the catalyst structure evolutions revealed directly by in-situ techniques are systematically summarized,such as phase,valence,electronic transfer,coordination,and spin states ***-situ revelation of intermediate adsorption/desorption behavior,and the real-time monitoring of the product nucleation,growth,and reconstruction evolution are equally emphasized in the *** interference factors,as well as in-situ signal assignment with the aid of theoretical calculations,are also ***,some major challenges and prospects of in-situ techniques for future catalysts research in the ORR process are proposed.

关键词： Oxygen reduction reaction Catalysts In-situ techniques Active sites Mechanisms

Variation of Zn content in soils under different land-use types in the Hetao oasis,Inner Mongolia of China

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Journal of Arid Land 2016年第6期8卷 861-870页

作者： ZHU Yangchun ZHAO Xueyong lian jie CHEN Min Naiman Desertification Research Station/Urat Desert-grassland Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Understanding the status and distribution of the micronutrient Zn in soils is important for managing plant growth and preventing soil pollution for agricultural irrigation systems in arid and semi-arid regions. In this study, a total of 195 soil samples from five soil layers （0-20, 20-40, 40-60, 60-80 and 80-100 cm） in the three land-use types （wasteland, forestland and cropland） after long-term agricultural fertilization and irrigation with Yellow River water were collected in the middle of the Hetao oasis, i.e. the Yongji irrigation sub-oasis. We analyzed the vertical and spatial distributions of Zn content and its relationship with soil properties to determine whether differences of Zn content existed in the soil profiles. The results revealed that the mean content of Zn was 107 mg/kg, 1.9 times higher than the background value （55.7 mg/kg） of the Hetao oasis and much lower than the secondary standard value （300 mg/kg） of the Chinese Environmental Quality Standard for Soils when pH〉7.5. Soil Zn contents were not significantly different and the coefficients of variation of Zn contents were less than 50% in the five soil layers. Soil Zn content was similar from southern to northern parts but increased from western to eastern parts in the sub-oasis. Soil Zn contents did not differ significantly among the three land-use types, but soil total nitrogen （TN） contents were significantly higher in the agriculturally managed forestland and cropland than in the wasteland （P〈0.05）. Zn was significantly and positively correlated with TN （F=36.6, P〈0.001）. The use of fertilizers may increase the content of Zn in soils, but flooding irrigation may minimize the differences in the spatial distribution of soil Zn content in the whole sub-oasis. This research is of important value for soil pollution control and sustainable land use management in arid and semi-arid regions.

关键词： fertilizer land-use type spatial distribution soil profile soil property