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Recent Progress and Regulation Strategies of Layered Materials as Cathode of Aqueous Zinc-Ion Batteries

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Energy & Environmental Materials 2024年第3期7卷 14-31页

作者： yuan yuan Si Wu Xiaoxue Song Jin yong Lee Baotao Kang School of Chemistry and Chemical Engineering University of JinanJinan 250022China Department of Chemistry Sungkyunkwan UniversitySuwon 16419Korea Shandong Hi-Speed Engineering Test Co. Ltd.Jinan 250022China

Aqueous zinc-ion batteries(ZIBs)have shown great potential in the fields of wearable devices,consumer electronics,and electric vehicles due to their high level of safety,low cost,and multiple electron *** layered cathode materials of ZIBs hold a stable structure during charge and discharge reactions owing to the ultrafast and straightforward(de)intercalation-type storage mechanism of Zn^(2+)ions in their tunable interlayer spacing and their abilities to accommodate other guest ions or ***,the challenges of inadequate energy density,dissolution of active materials,uncontrollable byproducts,increased internal pressure,and a large de-solvation penalty have been deemed an obstacle to the development of *** this review,recent strategies on the structure regulation of layered materials for aqueous zinc-ion energy storage devices are systematically ***,critical science challenges and future outlooks are proposed to guide and promote the development of advanced cathode materials for ZIBs.

关键词： layered cathode materials modifying strategies structure regulation zinc-ion batteries

Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

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Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming Xia yong-Jun Ye Shu-yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the *** these measurement methods,the closed-loop method is frequently ***,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation *** CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and *** this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the *** consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was *** effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were *** on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion *** CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

Metarelation2vec:A Metapath-Free Scalable Representation Learning Model for Heterogeneous Networks

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Tsinghua Science and Technology 2024年第2期29卷 553-575页

作者： Lei Chen yuan Li yong Lei Xingye Deng School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Computer Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China

Metapaths with specific complex semantics are critical to learning diverse semantic and structural information of heterogeneous networks(HNs)for most of the existing representation learning ***,any metapaths consisting of multiple,simple metarelations must be driven by domain *** sensitive,expensive,and limited metapaths severely reduce the flexibility and scalability of the existing models.A metapath-free,scalable representation learning model,called Metarelation2vec,is proposed for HNs with biased joint learning of all metarelations in a bid to address this ***,a metarelation-aware,biased walk strategy is first designed to obtain better training samples by using autogenerating cooperation probabilities for all metarelations rather than using expert-given ***,grouped nodes by the type,a common and shallow skip-gram model is used to separately learn structural proximity for each node ***,grouped links by the type,a novel and shallow model is used to separately learn the semantic proximity for each link ***,supervised by the cooperation probabilities of all meta-words,the biased training samples are thrown into the shallow models to jointly learn the structural and semantic information in the HNs,ensuring the accuracy and scalability of the *** experimental results on three tasks and four open datasets demonstrate the advantages of our proposed model.

关键词： metarelation random walk heterogeneous network metapath representation learning

Resource Allocation for Cognitive Network Slicing in PD-SCMA System Based on Two-Way Deep Reinforcement Learning

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China Communications 2024年第6期21卷 53-68页

作者： Zhang Zhenyu Zhang yong yuan Siyu Cheng Zhenjie School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Work Safety Intelligent Monitoring(Beijing University of Posts and Telecommunications) Beijing 100876China

In this paper,we propose the Two-way Deep Reinforcement Learning(DRL)-Based resource allocation algorithm,which solves the problem of resource allocation in the cognitive downlink network based on the underlay *** users(SUs)in the cognitive network are multiplexed by a new Power Domain Sparse Code Multiple Access(PD-SCMA)scheme,and the physical resources of the cognitive base station are virtualized into two types of slices:enhanced mobile broadband(eMBB)slice and ultrareliable low latency communication(URLLC)*** design the Double Deep Q Network(DDQN)network output the optimal codebook assignment scheme and simultaneously use the Deep Deterministic Policy Gradient(DDPG)network output the optimal power allocation *** objective is to jointly optimize the spectral efficiency of the system and the Quality of Service(QoS)of *** results show that the proposed algorithm outperforms the CNDDQN algorithm and modified JEERA algorithm in terms of spectral efficiency and QoS ***,compared with the Power Domain Non-orthogonal Multiple Access(PD-NOMA)slices and the Sparse Code Multiple Access(SCMA)slices,the PD-SCMA slices can dramatically enhance spectral efficiency and increase the number of accessible users.

关键词： cognitive radio deep reinforcement learning network slicing power-domain non-orthogonal multiple access resource allocation

Seismic responses of an intensively constructed metro station-passageway-shaft structure system

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 760-775页

作者： Ruohan LI yong yuan Hong CHEN Xinxing LI Emilio BILOTTA Department of Geotechnical Engineering Tongji UniversityShanghai 200092China Department of Civil Architectural and Environmental EngineeringUniversity of Naples Federico IINaples 80125Italy State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Tunnel Engineering&Rail Transit Design and Research Institute Shanghai 200235China

Intensive construction methods offer benefits for metro station development,yet they present challenges for seismic design due to the spatially asymmetric configuration of passageway-shaft *** this study,a detailed numerical model of a station-passageway-shaft structure system built using intensive construction methods was developed and the deformation and damage modes under seismic loadings were *** results indicate that inconsistent deformation between the shaft and the station generates interaction through the connecting passageway,leading to damage near the opening of the station structure and both ends of the connecting passageway Damage is more severe under longitudinal *** with the opening plan that spans four segments,the opening plan that spans five segments exacerbates the overall degree of damage to the structure *** transverse excitation,the presence of interior structures intensifies the damage to the station and connecting passageway,while with such internal structure in place the impact is relatively minor under longitudinal *** with steel segments near the station opening can appreciably attenuate the *** contrast,introducing flexible joints at both ends of the connecting passageway intensifies the ***,reinforcement using steel segments emerges as an optimal seismic mitigation strategy.

关键词： earthquake intensive construction metro station numerical simulation

Bridging microstructure and crystallography with the crack propagation behavior in Ti-6Al-4V alloy fabricated via dual laser beam bilateral synchronous welding

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Journal of Materials Science & Technology 2024年第7期174卷 1-14页

作者： Tingyan Yan yuan Liu Jianfeng Wang yong Zheng Xiaohong Zhan College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China

The microstructure evolution and crack propagation behavior were systematically and thoroughly inves-tigated inα/βTi-6Al-4V alloy obtained under the inhomogeneous heating effect of a coupled dual laser beam via a combination of postmortem electron backscattering diffraction analyses and numerical *** effect of microstructural attributes(grain size,grain boundary,dislocation)on the fracture property and crack propagation behavior was investigated based on thermodynamic and crystallographic analyses,as well as the examinations of dislocation density and the Burgers *** quantifying the degree of variant selection using the degree of variant selection(DVS)equation,it was found that the higher the energy input,the weaker the variant selection,as the secondaryαphase suppresses further dislocation-induced variant selection via autocatalytic nucleation and *** proportion of high an-gle grain boundaries(HAGBs)concentrated around 60°gradually increases with improving cooling rate,mainly due to the change in the tendency of martensite transformation to be *** grain refine-ment was the primary mechanism for the enhancement of Ti-6Al-4V alloy T-joints,while the suppression of crack propagation by HAGBs also played a crucial role in improving strength and *** crack propagation direction frequently changes when the order is approximately parallel to the short axis ofαmartensite grains,forming a zigzag propagation *** above findings should shed light on optimiz-ing dual laser beam bilateral synchronous welding(DLBSW)technology to tailor the microstructure and improve the mechanical properties of Ti-6Al-4V alloy T-joints.

关键词： Ti-6Al-4V alloy Microstructure Grain refinement Crack propagation Dual laser beam bilateral synchronous welding

Experimental and numerical study of hypervelocity impact damage on composite overwrapped pressure vessels

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Defence Technology（防务技术） 2024年第1期31卷 58-72页

作者： yong-Pan Duan Run-Qiang Chi Bao-Jun Pang yuan Cai Hypervelocity Impact Research Center Harbin Institute of TechnologyHarbin150080China College of Science Heilongjiang University of Science and TechnologyHarbin 150022China

Ground-based tests are important for studying hypervelocity impact(HVI)damage to spacecraft pressure vessels in the orbital debris *** analyzed the damage to composite overwrapped pressure vessels(COPVs)in the HVI tests and classified the damage into non-catastrophic damage and catastrophic *** proposed a numerical simulation method to further study non-catastrophic damage and revealed the characteristics and mechanisms of non-catastrophic damage affected by impact conditions and internal *** fragments of the catastrophically damaged COPVs were collected after the *** crack distribution and propagation process of the catastrophic ruptures of the COPVs were *** findings contribute to understanding the damage characteristics and mechanisms of COPVs by HVIs.

关键词： Orbital debris Hypervelocity impact Composite overwrapped pressure vessels Damage mechanisms

Triclosan-conjugated,Lipase-responsive Polymeric Micelles for Eradication of Staphylococcal Biofilms

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Chinese Journal of Polymer Science 2024年第6期42卷 718-728页

作者： Yan-Qiang Huang yuan-Feng Li yong Liu Lin-Qi Shi Guangxi Technology Innovation Cooperation Base of Prevention and Control Pathogenic Microbes with Drug Resistance Youjiang Medical University for NationalitiesBaise533000China Translational Medicine Laboratory the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou325035China Wenzhou Institute University of Chinese Academy of SciencesWenzhou325001China State Key Laboratory of Medicinal Chemical Biology Key Laboratory of Functional Polymer Materials of Ministry of Educationand Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin300071China

Bacterial biofilms present a significant challenge in treating drug-resistant infections,necessitating the development of innovative *** this study,we introduce triclosan-conjugated,lipase-responsive polymeric micelles designed to exploit biofilm properties and serve as a responsive drug delivery *** micelles were created using an amphiphilic block polymer synthesized via ring-opening polymerization ofε-caprolactone(CL)and triclosan-containing cyclic trimethylene carbonate(MTC-Tri).Poly(ethylene glycol)(PEG-OH)acted as the macro-initiator,resulting in micelles with a PEG shell that facilitated their penetration into bacterial *** important advantage of our micelles lies in their interaction with local bacterial lipases within *** lipases triggered rapid micelle degradation,releasing triclosan in a controlled *** liberated triclosan effectively eliminated bacteria embedded in the ***,the triclosan-conjugated micelles displayed minimal toxicity to murine fibroblasts,indicating their biocompatibility and *** finding emphasizes the potential application of these micelles in combatting drug resistance observed in bacterial *** triclosan-conjugated,lipase-responsive polymeric micelles exhibit promising characteristics for addressing drug resistance in bacterial *** harnessing biofilm properties and implementing a responsive drug delivery system,we seek to provide an effective solution in the fight against drug-resistant bacteria.

关键词： Self-assembly Polymer prodrug Ring-opening polymerization Biofilm eradication Cytotoxicity

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： yong YANG Ren-Sheng CHEN yong-Jian DING Hong-yuan LI Zhang-Wen LIU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming