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Space truss construction modeling based on on-orbit assembly motion feature

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Chinese Journal of Aeronautics 2024年第3期37卷 365-379页

作者： Changjie ZHAO Weizhong GUO Meng chen Jiaxing hu Youcheng HAN Rongfu LIN State Key Lab of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Institute of Aerospace System Engineering Shanghai Shanghai 201109China

More space truss construction has been planned to develop and utilize space *** trusses are designed in the way of large-scale,complex,modular,and on-orbit *** meet the upcoming challenge of large-scale space infrastructure construction,it is necessary to study space truss automation design and robotic *** paper proposes an ordinal finite screw adjacency matrix model(OFSAMM),focusing on the relationship between assembly motions,to express and compute a space truss *** this model,a space truss is abstracted as a set of ordered assembly motions,each of which is recorded as a finite screw as the basic element of the truss and its *** operation of truss transformation is also derived under this ***,the truss configuration,the assembly sequence,the truss sub-assembly,the truss components,and the on-orbit assembly task can be expressed and calculated in a unified model,which is calculated and stores the truss topology and assembly with the minimum storage *** the end of this paper,we introduce how to synthesize and optimize space truss design through two *** study will help to improve design ***,it provides a theoretical basis for the automatic construction of space truss structures,especially in the next stage.

关键词： Adjacency matrix Finite screw On-orbit construction modeling Space applications Space trusses Topology design

Accelerating solar driven CO_(2) reduction via sulfur-doping boosted water dissociation and proton transfer

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Nano Research 2024年第3期17卷 1056-1065页

作者： Ke Yan Liang chen Yangguang hu Ting Wang Cong chen Chao Gao Youju huang Benxia Li School of Chemistry and Chemical Engineering Key Laboratory of Surface&Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou 310018China College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of EducationHangzhou Normal UniversityHangzhou 311121China School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China

Exploring efficient photocatalysts for solar driven CO_(2) reduction with water(H_(2)O)as a proton donor is highly imperative but remains a great challenge because the synchronous enhancement of CO_(2) activation,H_(2)O dissociation and proton transfer is hardly achieved on a ***,the sluggish H_(2)O dissociation impedes the photocatalytic CO_(2) reduction reaction involving multiple proton–electron coupling transfer ***,a sulfur-doped BiOCl(S-BiOCl)photocatalyst with abundant oxygen vacancies(OV)is developed,which exhibits broadband-light harvesting across solar spectrum and distinct photothermal effect due to *** photocatalytic CO_(2) reduction with H_(2)O in a gas–solid system,the high CO yield of 49.76μmol·g_(cat)^(-1)·h^(-1) with 100%selectivity is achieved over the S-BiOCl catalyst under a simulated *** H_(2)O-assisted CO_(2) reduction reaction on S-BiOCl catalyst is triggered by photocatalysis and the photothermal heating further enhances the reaction *** kinetic isotope experiments indicate that the sluggish H_(2)O dissociation affects the whole photocatalytic CO_(2) reduction *** presence of oxygen vacancies promotes the adsorption and activation of H_(2)O and CO_(2),and the doped S sites play a crucial role in boosting H_(2)O dissociation and accelerating the dynamic migration of hydrogen *** a result,the ingenious integration of OV defects,S sites and photothermal effect in S-BiOCl catalyst conjointly contributes to the significant improvement in photocatalytic CO_(2) reduction performance.

关键词： BiOCl sulfur doping photocatalytic CO_(2)reduction H_(2)O activation proton feeding

Effect of Y substitution on the microstructure,magneto-optical,and thermal properties of(Tb_(1−x)Y_(x))_(3)Al_(5)O_(12)transparent ceramics

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Journal of Advanced Ceramics 2024年第4期13卷 529-538页

作者： Lixuan Zhang Dianjun hu Xiao Li Ziyu Liu chen hu Lexiang Wu Tingsong Li Dariusz Hreniak Jiang Li Transparent Ceramics Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China Institute of Low Temperature and Structure Research Polish Academy of SciencesWroclaw 50-422Poland

Faraday isolators can prevent the front-end system from disturbance and damage caused by a back-reflected beam,so they are important elements in laser *** magneto-optical materials are the most important component in Faraday isolators,the studies on magneto-optical materials have attracted much attention these ***_(3)Al_(5)O_(12)(TAG)ceramics are considered to be one of the most promising magneto-optical materials for visible to near-infrared wavelength band application because of their outstanding comprehensive magneto-optical ***,the optical quality of TAG ceramics needs further optimization to meet the application *** this work,high optical quality(Tb_(1−x)Y_(x))_(3)Al_(5)O_(12)(x=0,0.05,0.1,0.2,and 0.3)magneto-optical ceramics were fabricated successfully by solid-state reaction sintering combined with hot isostatic pressing(HIP)*** the ceramics obtained showed a single garnet phase for different values of x in the range *** addition of Y_(2)O_(3) was found to suppress the secondary phase and improve optical quality *** ceramic samples obtained had clear grain boundaries and possessed the in-line transmittance values of 82.9%at 1064 nm and 82.2%at 633 nm,*** Verdet constants of(Tb_(1−x)Y_(x))_(3)Al_(5)O_(12)ceramics with x=0,0.05,0.1,0.2,and 0.3 were−188.1,−175.4,−168.5,−143.0,and−119.9 rad/(T·m),*** thermal conductivity of TAG ceramics was found to be 5.23 W/(m·K)at 25℃,and when 20%Y was substituted in place of Tb,the thermal conductivity decreased by only 9.4%.

关键词： (Tb_(1−x)Y_(x))_(3)Al_(5)O_(12)ceramics magneto-optical materials optical quality thermal properties

Enhancing the electrochemical performance of Na metal anodes via local eutectic melting in porous Al-Cu alloy hosts

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Nano Research 2024年第7期17卷 6111-6118页

作者： Tao hu Qiang Wu cheng Wang Jialu chen Fu Su Zibo chen Yizhou Wang Jianyu chen Yanwen Ma Jin Zhao State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts&Telecommunications9 Wenyuan RoadNanjing 210023China Materials Science and Engineering King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia Suzhou Vocational Institute of Industrial Technology 1 Zhineng AvenueSuzhou International Education ParkSuzhou 215104China

Sodium(Na)metal batteries(SMBs)have emerged as promising alternatives to lithium metal batteries for large-scale energy storage applications,owing to their cost-effectiveness,abundance,and favorable redox ***,the practical implementation of SMBs faces several challenges associated with the Na metal anode,including the formation of dendrites,low Coulombic efficiency,and capacity ***,we propose a novel approach to enhance the electrochemical performance of Na metal anodes through a porous Al-Cu alloy host(PAC)fabricated by a local eutectic melting *** local eutectic melting facilitates the development of a conductive network,offering mechanical support,and the porous structure provides abundant channels for the diffusion of Na ions and accommodates volume fluctuations in the Na metal during charge–discharge ***,the PAC exhibits a high average Coulombic efficiency of 99.8%at 1 mA·cm^(−2)for 1 mAh·cm^(−2)and a low voltage polarization of 19 mV during 500 *** study provides valuable insight into the design and fabrication of highperformance Na metal anodes,which hold significant promise for the advancements of next-generation energy storage systems.

关键词： Na metal anode porous Al-Cu alloy porous current collector local eutectic melting

Salmonella Grumpensis Causing Diarrhea in Children—Shanghai Municipality,China,2023

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China CDC weekly 2024年第18期6卷 396-400,I0006,I0007页

作者： Yue Liu Xuebin Xu Wenqin Wang Wenjia Xiao Yi hu Xin chen Min chen Shanghai Municipal Center for Disease Control and Prevention ShanghaiChina Pudong New Area Center for Disease Control and Prevention ShanghaiChina Department of Epidemiology Key Laboratory of Public Health Safety of Ministry of EducationSchool of Public HealthFudan UniversityShanghaiChina

Summary What is already known about this topic?Foodborne diseases are a growing public health concern with a notable disease burden in *** is added by this report?Two children with diarrhea visited a healthcare facility within 24 hours on August 1 and 2,*** Grumpensis was detected in their stool samples by the public health *** genome sequencing(WGS)analysis revealed characteristics typical of outbreak *** the origin of the outbreak was unknown,the possibility of a hidden shared infection was deemed feasible.

关键词： diarrhea diseases Whole

A Prediction-Based Multi-Objective VM Consolidation Approach for Cloud Data Centers

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Computers, Materials & Continua 2024年第7期80卷 1601-1631页

作者： Xialin Liu Junsheng Wu Lijun chen Jiyuan hu School of Computer Science Northwestern Polytechnical UniversityXi’an710005China School of Computer Science and Technology Xi’an University of Posts and TelecommunicationsXi’an710021China Shaanxi Key Laboratory of Network Data Analysis and Intelligent Processing Xi’an University of Posts and TelecommunicationsXi’an710021China School of Software and Microelectronics Northwestern Polytechnical UniversityXi’an710005China School of Automation Xi’an University of Posts and TelecommunicationsXi’an710021China

Virtual machine(VM)consolidation aims to run VMs on the least number of physical machines(PMs).The optimal consolidation significantly reduces energy consumption(EC),quality of service(QoS)in applications,and resource *** paper proposes a prediction-basedmulti-objective VMconsolidation approach to search for the best mapping between VMs and PMs with good timeliness and practical *** use a hybrid model based on Auto-Regressive Integrated Moving Average(ARIMA)and Support Vector Regression(SVR)(HPAS)as a prediction model and consolidate VMs to PMs based on prediction results by HPAS,aiming at minimizing the total EC,performance degradation(PD),migration cost(MC)and resource wastage(RW)*** results usingMicrosoft Azure trace show the proposed approach has better prediction accuracy and overcomes the multi-objective consolidation approach without prediction(i.e.,Non-dominated sorting genetic algorithm 2,Nsga2)and the renowned Overload Host Detection(OHD)approaches without prediction,such as Linear Regression(LR),Median Absolute Deviation(MAD)and Inter-Quartile Range(IQR).

关键词： VM consolidation prediction multi-objective optimization machine learning

Structural and Ferroelectric Transition in Few-Layer HfO_(2) Films by First Principles Calculations

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Chinese Physics Letters 2024年第8期41卷 94-106页

作者： Ruiling Gao Chao Liu Bowen Shi Yongchang Li Bing Luo Rui chen wenbin Ouyang Heng Gao Shunbo hu Yin Wang Dongdong Li Wei Ren Materials Genome Institute State Key Laboratory of Advanced Special SteelShanghai Key Laboratory of High Temperature SuperconductorsInternational Center of Quantum and Molecular StructuresPhysics DepartmentInstitute for the Conservation of Cultural HeritageShanghai UniversityShanghai 200444China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Shanghai World Foreign Language Academy Shanghai 200233China Key Laboratory of Silicate Cultural Relics Conservation(Ministry of Education) Shanghai UniversityShanghai 200444China Hongzhiwei Technology(Shanghai)Co. Ltd.Shanghai 201206China Zhangjiang Laboratory Shanghai 201210China

The discovery of ferroelectricity in HfO_(2)-based materials with high dielectric constant has inspired tremendous research interest for next-generation electronic ***,films structure and strain are key factors in exploration of ferroelectricity in fluorite-type oxide HfO_(2) *** we investigate the structures and straininduced ferroelectric transition in different phases of few-layer HfO_(2) films(layer number𝑁=1–5).It is found that HfO_(2) films for all phases are more stable with increasing films *** them,the Pmn2_(1)(110)-oriented film is most stable,and the films of𝑁=4,5 occur with a𝑃21 ferroelectric transition under tensile strain,resulting in polarization about 11.8μC/cm^(2) along in-plane𝑎-*** ferroelectric transition is caused by the strain,which induces the displacement of Hf and O atoms on the surface to non-centrosymmetric positions away from the original paraelectric positions,accompanied by the change of surface Hf–O bond *** importantly,three new stable HfO_(2)2D structures are discovered,together with analyses of computed electronic structures,mechanical,and dielectric *** work provides guidance for theoretical and experimental study of the new structures and strain-tuned ferroelectricity in freestanding HfO_(2) films.

关键词： properties. ferroelectric positions

Overcoming the Na-ion conductivity bottleneck for the cost-competitive chloride solid electrolytes

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Journal of Energy Chemistry 2024年第8期95卷 1-8,I0001页

作者： Lv hu hui Li Fang chen Yating Liu Jinzhu Wang cheng Ma Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026AnhuiChina National Synchrotron Radiation Laboratory Hefei 230026AnhuiChina

Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or ***,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)*** addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid *** combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.

关键词： All-solid-state sodium batteries Ionic conductivities Solid electrolytes Chlorides High voltage stability

Atmospheric oxidation capacity and O_(3) formation in a coastal city of southeast China:Results from simulation based on four-season observation

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Journal of Environmental Sciences 2024年第2期136卷 68-80页

作者： Gaojie chen Taotao Liu Jinsheng chen Lingling Xu Baoye hu chen Yang Xiaolong Fan Mengren Li Youwei Hong Xiaoting Ji Jinfang chen Fuwang Zhang Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Minnan Normal University Zhangzhou 363000China College of Harbour and Coastal Engineering Jimei UniversityXiamen 361021China Environmental Monitoring Center of Fujian Fuzhou 350013China

The pollution of atmospheric ozone in China shows an obvious upward trend in the past ***,the studies on the atmospheric oxidation capacity and O_(3)formation in four seasons in the southeastern coastal region of China with the rapid urbanization remain ***,a four-season field observation was carried out in a coastal city of southeast China,using an observation-based model combining with the Master Chemical Mechanism,to explore the atmospheric oxidation capacity(AOC),radical chemistry,O_(3)formation pathways and *** results showed that the average net O_(3)production rate(14.55 ppbv/hr)in summer was the strongest,but the average O_(3)concentrations in autumn was *** AOC and ROx levels presented an obvious seasonal pattern with the maximum value in summer,while the OH reactivity in winter was the highest with an average value of 22.75 sec^(-1).The OH reactivity was dominated by oxygenated VOCs(OVOCs)(30.6%-42.8%),CO(23.2%-26.8%),NO_(2)(13.6%-22.0%),and alkenes(8.4%-12.5%)in different *** photolysis dominated OH primary source on daytime in winter,while in other seasons,HONO photolysis in the morning and ozone photolysis in the afternoon contributed *** analysis indicated that O_(3)production was controlled by VOCs in spring,autumn and winter,but a VOC-limited and NOx-limited regime in summer,and alkene and aromatic species were the major controlling factors to O_(3)***,the study characterized the atmospheric oxidation capacity and elucidated the controlling factors for O_(3)production in the coastal area with the rapid urbanization in China.

关键词： Atmospheric oxidation capacity Radical chemistry Ozone production Sensitivity analysis