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Journal of Advanced Ceramics 2024年第8期13卷 1164-1177页

作者： Peng liu Zhilin Tian Zhilin Chen Shuping Wen liya Zheng bin li School of Materials Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China

ZrP_(2)O_(7) is a promising wave-transparent material due to its low dielectric constant and low dielectric loss,but its inherent phase transition characteristic at approximately 300℃ limits its high-temperature ***,suppressing the phase transition is necessary for ZrP_(2)O_(7),to serve in extremely harsh *** this work,introducing Ti and Hf into ZrP_(2)O_(7) causes significant lattice distortion and an increase in entropy,both of which synergistically limit the crystal structure *** addition,enhanced phonon scattering by mismatch of atomic mass and local distortion leads to a reduction in the thermal *** distortions also cause changes in both bond length and tilting angle,so that(Ti_(1/3)Zr_(1/3)Hf_(1/3))P_(2)O_(7) does not undergo sudden expansion as does ZrP_(2)O_(7).(Ti_(1/3)Zr_(1/3)Hf_(1/3))ZrP_(2)O_(7) maintains excellent dielectric properties,which highlights it as a promising high-temperature wave-transparent material.

关键词： wave-transparent material medium-entropy ceramics phase transition dielectric constant thermal expansion thermal conductivity

Design of a Multifrequency Signal Parameter Estimation Method for the Distribution Network Based on HIpST

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Energy Engineering 2024年第3期121卷 729-746页

作者： bin liu Shuai liang Renjie Ding Shuguang li Tongliao Power Supply Company State Grid East Inner Mongolia Electric Power Co.Ltd.Tongliao028000China School of Electrical Engineering Northeast Electric Power UniversityJilin132012China

The application of traditional synchronous measurement methods is limited by frequent fluctuations of electrical signals and complex frequency components in distribution ***,it is critical to find solutions to the issues of multifrequency parameter estimation and synchronous measurement estimation accuracy in the complex environment of distribution *** utilizing the multifrequency sensing capabilities of discrete Fourier transform signals and Taylor series for dynamic signal processing,a multifrequency signal estimation approach based on HT-IpDFT-STWLS(HIpST)for distribution networks is ***,by introducing the Hilbert transform(HT),the influence of noise on the estimation algorithm is ***,signal frequency components are obtained on the basis of the calculated signal envelope spectrum,and the interpolated discrete Fourier transform(IpDFT)frequency coarse estimation results are used as the initial values of symmetric Taylor weighted least squares(STWLS)to achieve high-precision parameter estimation under the dynamic changes of the signal,and the method increases the number of discrete ***,the accuracy of this proposed method is verified by simulation *** show that this proposed method can accurately achieve the parameter estimation of multifrequency signals in distribution *** approach provides a solution for the application of phasor measurement units in distribution networks.

关键词： Discrete fourier transform taylor series hilbert transform multifrequency signal parameter estimation

SDH-FCOS:An Efficient Neural Network for Defect Detection in Urban Underground Pipelines

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Computers, Materials & Continua 2024年第1期78卷 633-652页

作者： bin Zhou Bo li Wenfei Lan Congwen Tian Wei Yao College of Computer Science South-Central Minzu UniversityWuhan430074China

Urban underground pipelines are an important infrastructure in cities,and timely investigation of problems in underground pipelines can help ensure the normal operation of *** to the growing demand for defect detection in urban underground pipelines,this study developed an improved defect detection method for urban underground pipelines based on fully convolutional one-stage object detector(FCOS),called spatial pyramid pooling-fast(SPPF)feature fusion and dual detection heads based on FCOS(SDH-FCOS)*** study improved the feature fusion component of the model network based on FCOS,introduced an SPPF network structure behind the last output feature layer of the backbone network,fused the local and global features,added a top-down path to accelerate the circulation of shallowinformation,and enriched the semantic information acquired by shallow *** ability of the model to detect objects with multiple morphologies was strengthened by introducing dual detection *** experimental results using an open dataset of underground pipes show that the proposed SDH-FCOS model can recognize underground pipe defects more accurately;the average accuracy was improved by 2.7% compared with the original FCOS model,reducing the leakage rate to a large extent and achieving real-time ***,our model achieved a good trade-off between accuracy and speed compared with other mainstream *** proved the effectiveness of the proposed model.

关键词： Urban underground pipelines defect detection SDH-FCOS feature fusion SPPF dual detection heads

A Physical Security Technology Based upon Doubly Multiple Parameters Weighted Fractional Fourier Transform

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China Communications 2024年第10期21卷 200-209页

作者： li Yong Sun Teng Sha Xuejun Song Zhiqun Wang bin Science and Technology on Communication Networks Laboratory Shijiazhuang 050081China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China Harbin Institute of Technology Harbin 150001China

Enhancing the security of the wireless communication is necessary to guarantee the reliable of the data transmission, due to the broadcast nature of wireless channels. In this paper, we provide a novel technology referred to as doubly multiple parameters weighted fractional Fourier transform(DMWFRFT), which can strengthen the physical layer security of wireless communication. This paper introduces the concept of DM-WFRFT based on multiple parameters WFRFT(MP-WFRFT), and then presents its four properties. Based on these properties, the parameters decryption probability is analyzed in terms of the number of parameters. The number of parameters for DM-WFRFT is more than that of the MP-WFRFT,which indicates that the proposed scheme can further strengthen the the physical layer security. Lastly, some numerical simulations are carried out to illustrate that the efficiency of proposed DM-WFRFT is related to preventing eavesdropping, and the effect of parameters variety on the system performance is associated with the bit error ratio(BER).

关键词： doubly multiple parameters weighted fractional Fourier transform(DM-WFRFT) physical layer security transform parameters variety

Semitransparent organic solar cells with high light utilization efficiency and color rendering index

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Science China Chemistry 2024年第7期67卷 2248-2256页

作者： Ni Gao Haijun bin Shangrong Wu RenéA.J.Janssen Yongfang li Laboratory of Advanced Optoelectronic Materials Suzhou Key Laboratory of Novel Semiconductor Materials and DevicesCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123China Molecular Materials and Nanosystems&Institute for Complex Molecular Systems Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands

Semitransparent organic solar cells(ST-OSCs)have garnered considerable attention as promising renewable energy technology for integrating photovoltaics into ***,there is a trade-off between power conversion efficiency(PCE)and average visible transmittance(AVT),which hinders the achievement of a high light utilization efficiency(LUE).In this study,we propose a valuable method to address this challenge by replacing the transparent top electrode,Ag,with a 20 nm layer of *** ST-OSCs based on the 20 nm Au electrode demonstrate superior exciton extraction,more efficient charge collection,and higher color-rendering index(CRI)due to their smoother surface,higher conductivity,and enhanced visible light transmittance,resulting in a significantly higher PCE of 13.67%and an enhanced AVT of 30.17%,contributing to a high LUE of 4.15%.Additionally,optically transparent dielectric layers,applied on the front and back sides of the ST-OSCs to further boost performance,delivered an impressive LUE of 4.93%,with PCE and AVT values reaching 14.44%and 34.12%,***,the champion ST-OSCs also exhibited a favorable CRI value of *** achievements represent the bestperforming ST-OSCs to date with both high LUE and CRI and hold significant implications for the prospective commercialization of ST-OSCs.

关键词： semitransparent organic solar cells power conversion efficiency average visible transmittance light utilization efficiency color-rendering index

Mars exploration——In situ K-Ar dating of jarosite

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Science China Earth Sciences 2024年第3期67卷 641-656页

作者： Jing YANG Dewen ZHENG Ying WU Hong CHEN li YANG bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

High-entropy catalysts for electrochemical water-electrolysis of hydrogen evolution and oxygen evolution reactions

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Frontiers in Energy 2024年第3期18卷 265-290页

作者： Simiao SHA Riyue GE Ying li Julie M.CAIRNEY Rongkun ZHENG Sean li bin liU Jiujun ZHANG Wenxian li School of Materials Science and Engineering Shanghai UniversityShanghai 200444China School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu 241000China Australian Centre for Microscopy and Microanalysis School of AerospaceMechanical and Mechatronic EngineeringThe University of SydneySydney NSW 2006Australia School of Physics The University of SydneySydney NSW 2006Australia School of Materials Science and Engineering UNSW Materials&Manufacturing Futures InstituteUniversity of New South WalesSydney NSW 2052Australia College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China

High entropy materials (HEMs) have developed rapidly in the field of electrocatalytic water-electrolysis for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) due to their unique properties. In particular, HEM catalysts are composed of many elements. Therefore, they have rich active sites and enhanced entropy stability relative to single atoms. In this paper, the preparation strategies and applications of HEM catalysts in electrochemical water-electrolysis are reviewed to explore the stabilization of HEMs and their catalytic mechanisms as well as their application in support green hydrogen production. First, the concept and four characteristics of HEMs are introduced based on entropy and composition. Then, synthetic strategies of HEM catalysts are systematically reviewed in terms of the categories of bottom-up and top-down. The application of HEMs as catalysts for electrochemical water-electrolysis in recent years is emphatically discussed, and the mechanisms of improving the performance of electrocatalysis is expounded by combining theoretical calculation technology and ex-situ/in situ characterization experiments. Finally, the application prospect of HEMs is proposed to conquer the challenges in HEM catalyst fabrications and applications.

关键词： high-entropy electrocatalysis synthetic methods water-electrolysis hydrogen and oxygen evolutions

Increase of chiral sensing ability in host-guest chemistry by magnetic anisotropy

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Science China Chemistry 2024年第8期67卷 2775-2782页

作者： Jia-liang Chen bin li Feng Yang Tiesheng Shi Xun-Cheng Su State Key Laboratory of Elemento-organic Chemistry Tianjin Key Laboratory of Biosensing and Molecular RecognitionCollege of ChemistryNankai UniversityTianjin 300071China College of Chemistry Chemical Engineering and Materials ScienceZaozhuang UniversityZaozhuang 277160China

Enantiomeric molecules generally play distinct functions in chemistry,biology,and *** physical and chemical properties of chiral analytes lay difficulty in discrimination and quantification of the *** report herein an efficient approach of increasing the chiral sensing ability ofβ-cyclodextrin(β-CD),a widely used host molecule,in the hostguest chemistry by magnetic anisotropy.A rigid and chiral lanthanide binding tag was attached to theβ-CD to amplify the changes of nuclear magnetic resonance(NMR)signals in the host-guest recognition *** installation of the paramagnetic lanthanide ion inβ-CD greatly enhances the enantiomeric discrimination up to 30-fold in comparison with the diamagneticβ-CD *** addition,the magnitude of the paramagnetic effects is tunable according to the diverse range of paramagnetic strength of the lanthanide *** reported method significantly increases the chiral sensing ability ofβ-CD,which can be applied to other host *** transferred paramagnetic effects,pseudocontact shifts(PCSs)and paramagnetic relaxation enhancements(PREs),from the host to the guest molecules,are valuable structural restraints to determine the absolute stereochemistry of the chiral *** strategy does not need modification of the analytes and is complementary to the reported analytical methods that rely on the functionalization of the chiral analytes.

关键词： chiral recognition nuclear magnetic resonance host-guest chemistry magnetic anisotropy lanthanide ions

SciCN:A Scientific Dataset for Chinese Named Entity Recognition

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Computers, Materials & Continua 2024年第3期78卷 4303-4315页

作者： Jing Yang bin Ji Shasha li Jun Ma Jie Yu College of Computer National University of Defense TechnologyChangsha410073China

Named entity recognition(NER)is a fundamental task of information extraction(IE),and it has attracted considerable research attention in recent *** abundant annotated English NER datasets have significantly promoted the NER research in the English *** contrast,much fewer efforts are made to the Chinese NER research,especially in the scientific domain,due to the scarcity of Chinese NER *** alleviate this problem,we present aChinese scientificNER dataset–SciCN,which contains entity annotations of titles and abstracts derived from 3,500 scientific *** manually annotate a total of 62,059 entities,and these entities are classified into six *** to English scientific NER datasets,SciCN has a larger scale and is more diverse,for it not only contains more paper abstracts but these abstracts are derived from more research *** investigate the properties of SciCN and provide baselines for future research,we adapt a number of previous state-of-theart Chinese NER models to evaluate *** results show that SciCN is more challenging than other Chinese NER *** addition,previous studies have proven the effectiveness of using lexicons to enhance Chinese NER *** by this fact,we provide a scientific domain-specific *** results demonstrate that our lexicon delivers better performance gains than lexicons of other *** hope that the SciCN dataset and the lexicon will enable us to benchmark the NER task regarding the Chinese scientific domain and make progress for future *** dataset and lexicon are available at:https://***/yangjingla/***.

关键词： Named entity recognition dataset scientific information extraction lexicon

Recent advances in molecular and nanoparticle probes for fluorescent bioanalysis

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Nano Research 2024年第7期17卷 6443-6474页

作者： Haowen Luo Lejie Tian Yaoming Zhang Yang Wu bin li Jianxi liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering Shandong Laboratory of Advanced Materials and Green ManufacturingYantai 264006China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

With the increasing emphasis on ecological safety and physical health,the detection and treatment of harmful substances and diseases are becoming more and more ***,efficiently monitoring these biological behaviors with high accuracy and sensitivity in real-time has shown prominent research *** use of fluorescent probes to analyze organisms has gained momentum in recent years,especially in the field of organ imaging and assisted cancer therapy,where fluorescent bioanalysis demonstrates significant *** this review,we explored the latest advancements in fluorescent molecular probes(e.g.,small-molecule,macro-molecule,supramolecule)and fluorescent nanoparticle probes(e.g.,quantum dots or nanoclusters,metal-organic frameworks,polymers,complexes)used as bioanalytical tools in various assays over the last three *** also delved into their detective mechanisms,specific application areas,and characterization tools for responsive *** review aims to showcase the most recent and comprehensive research progress in fluorescent bioanalysis based on molecular and nanoparticle probes,offering guidance for future developments in the design and fabrication of fluorescent probes and their potential applications.

关键词： fluorescent biosensing bioimaging disease diagnosis tumor detection and treatment