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Tungsten 2024年第2期6卷 422-427页

作者： Xiu-Li Wang Yong-Zhen Chen Zhi-Han chang Yu-Chun Lin Jing-Yi Ma College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell Jinzhou 121013China

By employing a new semi-rigid pyrazole-amide-derived bis(pyridyl)ligand[N,N'-bis(4-picolylamine)-1-hydropyrazole(4-dpap)],a new homopolymolybdate-based two-dimensional(2d)plate-like complex[Co(4-dpap)(H_(2)O)(β-Mo_(8)O_(2)6)1/2](1)has been prepared under solvothermal condition and structurally ***β-Mo_(8)anions are fi xed between the 2d metal–organic networks[Co(4-dpap)(H_(2)O)]n 2n+via hydrogen-bonding *** 1 possesses satisfactory specifi c capacitance of 1512.4 F·g^(−1)(current density:1 A·g^(−1))and good cycling stability(90.8%after 1000 cycles).Moreover,1 represents a promising amperometric sensor for measurement of Cr(Ⅵ)with low detection limit(0.042μmol·L^(−1))and high *** insertion ofβ-Mo_(8)anions between the unique 2d metal−organic networks improves the active area of polyoxometalates,which further promotes electrochemical performance.

关键词： Homopolymolybdate Metal–organic network Pyrazole-amide-derived bis(pyridyl)ligand Supercapacitor Electrochemical sensor

deep learning-based semantic segmentation of human features in bath scrubbing robots

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Biomimetic Intelligence & Robotics 2024年第1期4卷 70-79页

作者： Chao Zhuang Tianyi Ma Bokai Xuan Cheng chang Baichuan An Minghuan Yin Hao Sun School of Artificial Intelligence and data Science Hebei University of TechnologyTianjin 300401China Engineering Research Center of Intelligent Rehabilitation device and detection Technology Ministry of EducationTianjin 300401China

With the rise in the aging population,an increase in the number of semidisabled elderly individuals has been noted,leading to notable challenges in medical and healthcare,exacerbated by a shortage of nursing *** study aims to enhance the human feature recognition capabilities of bath scrubbing robots operating in a water fog *** investigation focuses on semantic segmentation of human features using deep learning ***,3d point cloud data of human bodies with varying sizes are gathered through light detection and ranging to establish human ***,a hybrid filtering algorithm was employed to address the impact of the water fog environment on the modeling and extraction of human ***,the network is refined by integrating the spatial feature extraction module and the channel attention module based on *** results indicate that the algorithm adeptly identifies feature information for 3d human models of diverse body sizes,achieving an overall accuracy of 95.7%.This represents a 4.5%improvement compared with the PointNet network and a 2.5%enhancement over mean intersection over *** conclusion,this study substantially augments the human feature segmentation capabilities,facilitating effective collaboration with bath scrubbing robots for caregiving tasks,thereby possessing significant engineering application value.

关键词： 3d point cloud Human model LidAR Semantic segmentation

Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat

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Journal of Integrative Agriculture 2024年第5期23卷 1523-1540页

作者： Zhikai Cheng Xiaobo Gu Yadan du Zhihui Zhou Wenlong Li Xiaobo Zheng Wenjing Cai Tian chang Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid AreasMinistry of Education/Northwest A&F University Yangling712100China

In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter *** on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral *** machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried *** results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth *** accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of *** purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral *** results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching.

关键词： mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle

Bone tissue engineering scaffold materials: Fundamentals, advances, and challenges

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Chinese Chemical Letters 2024年第2期35卷 176-186页

作者： chang Xu Zhize Liu Xi Chen Yang Gao Wenjun Wang Xijing Zhuang Hao Zhang Xufeng dong department of Cardiovascular Surgery Central Hospital of Dalian University of TechnologyDalian 116089China School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China department of Orthopaedics Central Hospital of Dalian University of TechnologyDalian 116089China department of dermatology Allergologyand VenereologyUniversity of LübeckLübeck 23562Germany

Bone damage caused by trauma and tumors is a serious problem for human health, therefore, three-dimensional (3d) scaffolding materials that stimulate and promote the regeneration of broken bone tissues have become the focus of current research in the field of bone damage *** this regard, a preferential combination of materials and preparation techniques is considered crucial for the preparation of advanced bone tissue engineering scaffolds to better facilitate the regeneration of broken *** this review, current research advances and challenges in bone tissue engineering scaffolds are discussed and analyzed in ***, we elucidated the structure and self-healing mechanism of bone ***, the main applications of different materials, including inorganic and organic materials, in bone tissue engineering scaffolds are ***, we overview the latest research progress of the mainstream preparation strategies of bone tissue engineering scaffolds, and provide an in-depth analysis of the different advantages of each ***, promising future directions and challenges of bone tissue engineering scaffolds are systematically discussed.

关键词： Biomaterials Bone defects Tissue engineering Scaffolds Osteogenesis

Research Progress in Enantioselective Radical desymmetrization Reactions

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CCS Chemistry 2024年第7期6卷 1612-1627页

作者： chang-Jiang Yang Lin Liu Qiang-Shuai Gu Xin-Yuan Liu department of Chemistry and dongguan Key Laboratory for data Science and Intelligent Medicine Great Bay UniversityDongguan 523000 Shenzhen Grubbs Institute Department of Chemistryand Guangming Advanced Research InstituteSouthern University of Science and TechnologyShenzhen 518055 Academy for Advanced Interdisciplinary Studies and department of Chemistry Southern University of Science and TechnologyShenzhen 518055

Enantioselective radical desymmetrization is a highly effective approach for rapidly creating enantioenriched molecules,introducing dramatically increased structural complexity from readily available prochiral or meso compound *** strategic modes have been developed for these reactions,which differ in the nature of the stereo-determining *** first category deals primarily with the stereoselective desymmetrization of closed-shell radical precursors or functional reagents,whereas the second category achieves desymmetrization by stereoselectively functionalizing open-shell radical *** mini-review explores the research progress in this growing field,aiming to elucidate mechanistic scenarios related to stereochemical ***,it offers insights into the challenges and opportunities that lie ahead for further development.

关键词： radical desymmetrization enantioselective desymmetrization radical functionalization transition metal catalysis asymmetric catalysis

Addressable structured light system using metasurface optics and an individually addressable VCSEL array

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Photonics Research 2024年第6期12卷 1129-1137页

作者： CHENYANG WU XUANLUN HUANG YIPENG JI TINGYU CHENG JIAXING WANG NAN CHI SHAOHUA YU CONNIE J.chang-HASNAIN School of Information Science and Technology Fudan UniversityShanghai 200433China Berxel Photonics Co. Ltd.Shenzhen 518071China Peng Cheng Laboratory Shenzhen 518055China Chinese University of Hong Kong Shenzhen 518172China

Structured-light(SL)based 3d sensors have been widely used in many *** SL is the most widely deployed among all SL sensors due to its light weight,compact size,fast video rate,and low *** transmitter(known as the dot projector)consists of a randomly patterned vertical-cavity surface-emitting laser(VCSEL)array multiplicated by a diffractive optical element(dOE)with a fixed repeated *** that the separation of any two speckles is only one known and fixed number(albeit random),there are no other known scales to cal-ibrate or ***,typical SL sensors require extensive in-factory calibrations,and the depth resolution is limited to 1 mm at-60 cm *** this paper,to the best of our knowledge,we propose a novel dot projector and a new addressable SL(ASL)3d sensor by using a regularly spaced,individually addressable VCSEL array,multiplicated by a metasurface-dOE(MdOE)into a random pattern of the *** turning on or off the VCSELs in the array provides multiple known distances between neighboring speckles,which is used as a“built-in caliper”to achieve higher accuracy of *** as a precise“vernier caliper,”the addressable VCSEL array enables fine control over speckle positions and high detection *** experimentally dem-onstrated that the proposed method can result in sub-hundred-micron level *** new concept opens new possibilities for applications such as 3d computation,facial recognition,and wearable devices.

关键词： speckle light surface

Vertically grown MoS_(2)nanosheets on graphene with defect-rich structure for efficient sodium storage

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Rare Metals 2024年第3期43卷 1062-1071页

作者： Ying Wang Jia-Peng He Han-Qing Pan Qing-Peng Wang Lei Zhang Yong-chang Liu Qing-Hong Wang School of Chemistry&Materials Science Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional MaterialsJiangsu Normal UniversityXuzhou221116China Institute of Biopharmaceutical Research Liaocheng UniversityLiaocheng252059China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing100083China Centre for Catalysis and Clean Energy Gold Coast CampusGriffith UniversityGold CoastQLD4222Australia

The synthesis of a perpendicular growth structure of MoS_(2)nanosheets on graphene for efficient sodium storage is challenging yet ideal due to the benefits of open ion diffusion channels and high electronic *** this study,we have successfully fabricated a novel structure of vertical MoS_(2)nanosheets on graphene,with ZnS nanoparticles serving as bonding points(MoS_(2)/ZnS/G),through a facile hydrothermal *** the synthesis process,Zn^(2+)not only acts as a landing site for the vertical growth of MoS_(2)nanosheets but also triggers the formation of a defect-rich structure in the final *** unique architecture of MoS_(2)/ZnS/G effectively combines the advantages of a vertically aligned geometry and a defectrich structure for energy *** resulting structure displays shortened transport paths for electrons/ions,enhanced conductivity,improved structural integrity,and an increased number of active sites for promising electrochemical *** expected,when used as anode for sodium-ion batteries,the as-synthesize d MoS_(2)/ZnS/G exhibits excellent rate capability(high capacity of 298 mAh·g^(-1)at 5 A·g^(-1))and good cycling stability(a capacity decay of 0.056%per cycle after 500 cycles at 1 A·g^(-1)).According to the kinetic investigations,the electrochemical process of the MoS_(2)/ZnS/G sample is primarily governe d by a pseudocapacitive behavior,which enhances the charge/discharge kinetics and allows the MoS_(2)/ZnS/G structure to remain intact during cycling.

关键词： MoS_(2) Perpendicular growth Graphene Sodium storage Electrochemical performance

Stereodivergent synthesis ofα-fluoroα-azaarylγ-butyrolactones via cooperative copper and iridium catalysis

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Fundamental Research 2024年第1期4卷 77-85页

作者： Kui Tian Xin chang Lu Xiao Xiu-Qin dong Chun-Jiang Wang College of Chemistry and Molecular Sciences Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan UniversityWuhan 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Suzhou Institute of Wuhan University Suzhou 215123China

The development of stereodivergent synthetic methods to access all four stereoisomers of biologically importantα-fluoroγ-butyrolactones containing vicinal stereocenters is of great importance and poses a formidable challenge owing to ring strain and steric ***,a novel asymmetric[3+2]annulation ofα-fluoroα-azaaryl acetates with vinylethylene carbonate was successfully developed through Cu/Ir-catalyzed cascade allylic alkylation/lactonization,affording a variety of enantioenrichedα-fluoroγ-butyrolactones bearing vicinal stereogenic centers with high reaction efficiency and excellent levels of both stereoselectivity and regioselectivity(up to 98%yield,generally>20:1 dr and>99%ee).Notably,all four stereoisomers of these pharmaceutically valuable molecules could be accessed individually via simple permutations of two enantiomeric *** addition,other azaaryl acetates bearingα-methyl,α-chlorine orα-phenyl group were tolerated well in this *** mechanistic investigations were conducted to explore the process of this bimetallic catalysis based on the results of reaction intermediates,isotopic labelling experiments,and kinetic studies.

关键词： Asymmetric catalysis α-Fluoroγ-butyrolactones Synergistic catalysis Cascade reaction Stereodivergent synthesis

High temperature polyimide nanocomposites containing twodimensional nanofillers for improved thermal stability and capacitive energy storage performance

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Nano Research 2024年第8期17卷 7746-7755页

作者： ding Ai Yuting Han Zongliang Xie Xi Pang Yuan chang He Li Chenglong Wu Yonghong Cheng Guanglei Wu State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of Materials for Energy and Environment State Key Laboratory of Bio-Fibers and Eco-TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Future electronic devices toward high integration and miniaturization demand reliable operation of dielectric materials at high electric fields and elevated ***,the electrical deterioration caused by Joule heat generation remains a persistent challenge to ***,the solution-processed polyimide(PI)nanocomposites with unique two-dimensional(2d)alumina nanoplates are *** improvements in the breakdown strength,charge–discharge efficiency and discharged energy density at elevated temperatures have been demonstrated in the composites,owing to simultaneously suppressed conduction loss and increased thermal conductivity upon the incorporation of 2d Al_(2)O_(3) nanofillers possessing excellent dielectric insulation and thermophysical *** predominance of Al_(2)O_(3) nanoplates in enhancing thermal stability and high-temperature capacitive performance over nanoparticles and nanowires is validated experimentally and is further rationalized via finite element ***,the Al_(2)O_(3) nanoplates filled PI nanocomposite exhibits a hightemperature capability up to 200℃ and remarkable efficiency(e.g.≥95% at 200 MV/m)over a wide temperature range,which outperforms commercial dielectric polymers and rivals the state-of-the-art polyimide nanocomposites.

关键词： capacitors polymer nanocomposites high temperature energy storage thermal stability

Spin direction dependent quantum anomalous Hall effect in two-dimensional ferromagnetic materials

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Chinese Physics B 2024年第4期33卷 613-621页

作者：杨宇贤张昌文 School of Physics and Technology University of JinanJinan 250022China

We propose a scheme for realizing the spin direction-dependent quantum anomalous Hall effect(QAHE)driven by spin-orbit couplings(SOC)in two-dimensional(2d)*** on the sp^(3)tight-binding(TB)model,we find that these systems can exhibit a QAHE with out-of-plane and in-plane magnetization for the weak and strong SOC,respectively,in which the mechanism of quantum transition is mainly driven by the band inversion of p_(x,y)/p_(z)*** a concrete example,based on first-principles calculations,we realize a real material of monolayer 1T-SnN_(2)/PbN_(2)exhibiting the QAHE with in-plane/out-of-plane magnetization characterized by the nonzero Chern number C and topological edge *** findings provide useful guidance for the pursuit of a spin direction-dependent QAHE and hence stimulate immediate experimental interest.

关键词： topological phase transition quantum anomalous Hall effect first-principles calculations