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Mg-doped,carbon-coated,and prelithiated SiO_(x) as anode materials with improved initial Coulombic efficiency for lithium-ion batteries

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Carbon Energy 2024年第3期6卷 204-214页

作者： Bin Liu Jie Liu Cheng Zhong Wenbin Hu Key Laboratory of Advanced Ceramics and Machining technology(Ministry of Education) School of Materials Science and EngineeringTianjin UniversityTianjinChina Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjinChina Joint School of National university of Singapore and Tianjin university TianjinChina International Campus of Tianjin university Binhai New CityFuzhouChina

Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first *** this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing *** show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the *** obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg *** the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%).

关键词： initial Coulombic efficiency lithium-ion batteries magnesium doping prelithiation silicon suboxide

Engineering vascularized organotypic tissues via module assembly

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International Journal of Extreme Manufacturing 2024年第1期6卷 155-175页

作者： Zhenzhen Zhou Changru Liu Yuting Guo Yuan Pang Wei Sun Biomanufacturing Center Department of Mechanical EngineeringTsinghua UniversityHaidian DistrictBeijing 100084People’s Republic of China Biomanufacturing and Rapid Forming technology Key Laboratory of Beijing Beijing 100084People’s Republic of China Key Laboratory for Advanced Materials Processing technology Ministry of EducationBeijing 100084People’s Republic of China Department of Mechanical Engineering Drexel UniversityPhiladelphiaPA 19104United States of America

Adequate vascularization is a critical determinant for the successful construction and clinical implementation of complex organotypic tissue models. Currently, low cell and vessel density and insufficient vascular maturation make vascularized organotypic tissue construction difficult,greatly limiting its use in tissue engineering and regenerative medicine. To address these limitations, recent studies have adopted pre-vascularized microtissue assembly for the rapid generation of functional tissue analogs with dense vascular networks and high cell density. In this article, we summarize the development of module assembly-based vascularized organotypic tissue construction and its application in tissue repair and regeneration, organ-scale tissue biomanufacturing, as well as advanced tissue modeling.

关键词： vascularized organotypic tissue module assembly regenerative medicine tissue engineering

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Design Research of a Novel Aftercool-Humidifier Concept for Humid Air Turbine Cycle

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Journal of Thermal Science 2024年第3期33卷 951-969页

作者： ZHANG Junzheng XU Zhen School of Energy and Power Engineering Shandong UniversityJi’nan250061China Shandong Engineering Laboratory for High-efficiency Energy Conservation and Energy Storage technology&Equipment Shandong UniversityJi’nan250061China

Humid air turbine cycle(HAT)has potential of electrical efficiencies comparable to combined cycle,with lower investment cost and NO_(x) *** typical heat exchanger network of HAT consists of intercooler(if there is),aftercooler,recuperator,economizer and humidifier,which brings higher efficiency but makes the system more *** simplify HAT layout,a novel humidifier concept is proposed by integrating the aftercooler into traditional counter-current *** on this concept,a one-dimensional model including pressure drop and exergy calculation is established to distinguish the thermodynamic and hydrodynamic characteristics,and then the structural parameters,such as the number of rows and columns,tube diameter,pitch and type for a micro HAT are *** results show that the aftercool-humidifier plays the same role as original aftercooler and humidifier,and can match the in-tube air,out-tube air and water stream well with lower *** the case of micro HAT cycle,the volume of heat and mass transfer area can be reduced by 47%compared with traditional *** major thermal resistance occurred in the convection heat transfer process inside the tube;however,using enhanced tube cannot effectively improve the compactness of device.

关键词： humid air turbine cycle humidifier thermodynamic analysis one-dimensional model

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Rule acquisition of three-way semi-concept lattices in formal decision context

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CAAI Transactions on Intelligence technology 2024年第2期9卷 333-347页

作者： Jie Zhao Renxia Wan Duoqian Miao Boyang Zhang School of Mathematics and Information Science North Minzu UniversityYinchuanNingxiaChina Department of Computer Science and technology Tongji UniversityShanghaiChina Department of Computer Science Bowling Green State UniversityBowling GreenOhioUSA

Three-way concept analysis is an important tool for information processing,and rule acquisition is one of the research hotspots of three-way concept ***,compared with three-way concept lattices,three-way semi-concept lattices have three-way operators with weaker constraints,which can generate more *** this article,the problem of rule acquisition for three-way semi-concept lattices is discussed in *** authors construct the finer relation of three-way semi-concept lattices,and propose a method of rule acquisition for three-way semi-concept *** authors also discuss the set of decision rules and the relationships of decision rules among object-induced three-way semi-concept lattices,object-induced three-way concept lattices,classical concept lattices and semi-concept ***,examples are provided to illustrate the validity of our conclusions.

关键词： finer relation rule acquisition three-way concept analysis three-way semi-concept lattices

Sliding behaviors of the trapezoidal roof rock block under a lateral dynamic disturbance

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 741-760页

作者： Feng Dai Wancheng Zhu Min Ren Shunchuan Wu Leilei Niu Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming650093China Center for Rock Instability and Seismicity Research Department of Mining EngineeringSchool of Resource and Civil EngineeringNortheastern UniversityShenyang110819China

The surrounding rock of underground space is always affected by external dynamic disturbance from the side position,such as blasting vibration from a stope at the same level or seismic waves from adjacent strata.A series of laboratory tests,numerical simulations and theoretical analyses were carried out in this study to disclose the sliding mechanism of roof rock blocks under lateral ***,the experiments on trapezoidal key block under various clamping loads and disturbance were conducted,followed by numerical simulations using the fast Lagrangian analysis of continua(FLAC3D).Then,based on the conventional wave propagation model and the classical shear-slip constitutive model,a theoretical model was proposed to capture the relative displacement between blocks and the sliding displacement of the key *** results indicate that the sliding displacement of the key block increased linearly with the disturbance energy and decreased exponentially with the clamping load when the key block was disturbed to slide(without instability).Meanwhile,when the key block was disturbed to fall,two types of instability process may appear as immediate type or delayed *** addition,the propagation of stress waves in the block system exhibited obvious low-velocity and lowfrequency characteristics,resulting in the friction reduction effect appearing at the contact interface,which is the essential reason for the sliding of rock *** results can be applied to practical underground engineering and provide valuable guidance for the early detection and prevention of rockfalling disasters.

关键词： Lateral dynamic disturbance Trapezoidal rock block system Low-velocity and low-frequency wave Friction reduction effect Instability mode

Energy-Efficient D2D-Aided Dual UAV Data Collection

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Chinese Journal of Electronics 2024年

作者： Qiulei HUANG Wei WANG Zhaohui SONG Nan ZHAO School of Information and Communication Engineering Dalian University of Technology Space Information Research Institute Hangzhou Dianzi University

Aided by device-to-device(D2D) connections, unmanned aerial vehicle(UAV) can significantly enhance the coverage of wireless communications. In this paper, we consider a data collection system with the assistance of D2D, where two fixed-wing UAVs as aerial base stations cooperatively serve the ground devices. To accommodate more devices, we propose two effective algorithms to establish the multi-hop D2D connections. Then, the user scheduling, UAV trajectory, and transmit power are jointly optimized to maximize the energy efficiency, which is a non-convex problem. Accordingly, we decompose it into three subproblems. The scheduling optimization is first converted into a linear programming. Then, the trajectory design and the transmit power optimization are reformulated as two convex problems by the Dinkelbach method. Finally, an iterative algorithm is proposed to effectively solve the original problem. Simulation results are presented to verify the effectiveness of the proposed scheme.

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Deterministic learning-based neural output-feedback control for a class of nonlinear sampled-data systems

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Science China(Information Sciences) 2024年第09期67卷 164-183页

作者： Yu ZENG Fukai ZHANG Tianrui CHEN Cong WANG School of Automation Science and Engineering South China University of Technology School of Control Science and Engineering Shandong University

This study investigates the deterministic learning(DL)-based output-feedback neural control for a class of nonlinear sampled-data systems with prescribed performance(PP). Specifically, first, a sampleddata observer is employed to estimate the unavailable system states for the Euler discretization model of the transformed system dynamics. Then, based on the observations and backstepping method, a discrete neural network(NN) controller is constructed to ensure system stability and achieve the desired tracking performance. The noncausal problem encountered during the controller deduction process is resolved using a command filter. Moreover, the regression characteristics of the NN input signals are demonstrated with the observed states. This ensures that the radial basis function NN, based on DL theory, meets the partial persistent excitation condition. Subsequently, a class of discrete linear time-varying systems is proven to be exponentially stable, achieving partial convergence of neural weights to their optimal/actual values. Consequently, accurate modeling of unknown closed-loop dynamics is achieved along the system trajectory from the output-feedback control. Finally, a knowledge-based controller is developed using the modeling *** controller not only enhances the control performance but also ensures the PP of the tracking error. The effectiveness of the scheme is illustrated through simulation results.

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Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface

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Geodesy and Geodynamics 2024年第1期15卷 1-12页

作者： Lei Yang Jianjun Wang Caijun Xu School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Collaborative Innovation Center of Geospatial technology Wuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan UniversityWuhan 430079China

Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,*** spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among *** we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction *** results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,*** Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%*** factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench.

关键词： The 2020-2021 Alaska earthquake sequence Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap

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Multiporphyrinic architectures:Advances in structural design for photodynamic therapy

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Aggregate 2024年第1期5卷 67-84页

作者： Yuwei Gao Yan Li Zhengwei Xu Shuangjiang Yu Junqiu Liu Hongcheng Sun College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of EducationHangzhou Normal UniversityHangzhouChina

Rationally designed multiporphyrinic architectures for boosting photodynamic therapy(PDT)have attracted significant attentions recently years due to their great potential for light-mediated generation of reactive oxygen ***,there is still a gap between the structure design and their PDT performance for biomedical *** tutorial review provides a historical overview on(i)the basic concept of PDT for deeply understanding the porphyrin-mediated PDT reactions,(ii)developing strategies for constructing porphyrinic architectures,like nanorings,boxes,metal-organic frameworks(MOFs),covalent-organic frameworks(COFs),vesicles,etc.,where we classified into the following three categories:multiporphyrin arrays,porphyrinic frameworks,and others porphyrin assemblies,(iii)the various application scenarios for clinical cancer therapy and antibacterial ***,the existing challenges and future perspectives on the innovation of porphyrinic architectures for clinical PDT applications are mentioned in the end ***,the porphyrinic nanomaterials with atomically precise architectures provide an ideal platform for investigating the relationship between structures and PDT outputs,design of personalized“all-in-one”theranostic agents,and the popularization and application in wider biomedical fields.

关键词： covalent-organic frameworks(COFs) metal-organic frameworks(MOFs) multiporphyrin arrays photodynamic therapy(PDT) porphyrinic architectures