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Silk damping in scalar-induced gravitational waves: a novel probe for new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 79-85页

作者： yan-Heng yu Sai Wang Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences

Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～10～3-10～4 GeV, while space-and ground-based interferometers to those with mass ～10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.

关键词： scalar-induced gravitational waves Silk damping new physics

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

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Tungsten 2025年第1期7卷 112-119页

作者： Jia-Hui Li Qing Zhao Dong-Ao Mao Kun Zhou Bao-Kuan Chen yan-Feng bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

关键词： Modular construction Photothermal conversion Polyoxometalate Thiacalixarene

Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang yuefeng yan Zhen Wang Guansheng Ma Dechang Jia Xiaoxiao Huang yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching

GFRF R-CNN:Object Detection Algorithm for Transmission Lines

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Computers, Materials & Continua 2025年第1期82卷 1439-1458页

作者： Xunguang yan Wenrui Wang Fanglin Lu Hongyong Fan Bo Wu Jianfeng yu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Sciences Beijing100049China Jingwei Textile Machinery Co. Ltd.Beijing100176China

To maintain the reliability of power systems,routine inspections using drones equipped with advanced object detection algorithms are essential for preempting power-related *** increasing resolution of drone-captured images has posed a challenge for traditional target detection methods,especially in identifying small objects in high-resolution *** study presents an enhanced object detection algorithm based on the Faster Regionbased Convolutional Neural Network(Faster R-CNN)framework,specifically tailored for detecting small-scale electrical components like insulators,shock hammers,and screws in transmission *** algorithm features an improved backbone network for Faster R-CNN,which significantly boosts the feature extraction network’s ability to detect fine *** Region Proposal Network is optimized using a method of guided feature refinement(GFR),which achieves a balance between accuracy and *** incorporation of Generalized Intersection over Union(GIOU)and Region of Interest(ROI)Align further refines themodel’s *** results demonstrate a notable improvement in mean Average Precision,reaching 89.3%,an 11.1%increase compared to the standard Faster *** highlights the effectiveness of the proposed algorithm in identifying electrical components in high-resolution aerial images.

关键词： Faster R-CNN transmission line object detection GIOU GFR

Analysis of Micromechanical Properties at the Interface of Pre-wet SBS Modified Asphalt Mixture Based on Molecular Simulation Technology

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 103-113页

作者： CHEN Wuxing CHEN Shuang yu yan ZHANG Jiangyi XU Haiyang GUO Wei School of Mines China University of Mining and TechnologyXuzhou 221000China College of Construction Engineering Jilin Uni-versityChangchun 130026China

The pre-wetting of aggregate surface is a means to improve the interface performance of SBS modified asphalt and *** effect of pre-wetting technology on the interaction between SBS modified asphalt and aggregate was analyzed by molecular dynamics *** diffusion coefficient and concentration distribution of SBS modified asphalt on aggregate surface are *** simulation results show that the diffusion coefficient of the aggregate surface of SBS modified asphalt is increased by 47.6%and 70.5%respectively after 110#asphalt and 130#asphalt are *** concentration distribution of SBS modified asphalt on the aggregate surface after pre-wetting is more *** to the results of interface energy calculation,the interface energy of SBS modified bitumen and aggregate can be increased by about 5%after *** to the results of molecular dynamics simulation,the pre-wetting technology can effectively improve the interface workability of SBS modified bitumen and aggregate,so as to improve the interface performance.

关键词： pre-wet oil-stone interface interface interaction interface mechanics molecular dynamics simulation

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机器翻译中的歧异性研究现状综述

兰州文理学院学报（社会科学版） 2017年第5期33卷 106-111页

作者：余碧燕西安交通大学外国语学院陕西西安710049

语际差异是无法消除的客观事实,因而歧异性成为翻译研究必须面对的问题,尤其是对于高度注重形式化语言的机器翻译来说。本文从歧异性的定义、分类以及国内外研究成果三个方面对这一概念进行梳理介绍,以便让国内翻译研究人员对翻译歧异... 详细信息

语际差异是无法消除的客观事实,因而歧异性成为翻译研究必须面对的问题,尤其是对于高度注重形式化语言的机器翻译来说。本文从歧异性的定义、分类以及国内外研究成果三个方面对这一概念进行梳理介绍,以便让国内翻译研究人员对翻译歧异性有更深入的了解。对于英汉翻译歧异性研究而言,形成跨语系的完整的理论模式存在一定困难,期待各领域重视理论研究、具体问题具体分析、实现跨学科合作发展,从而推动机器翻译实现长足进步。

关键词：翻译歧异性机器翻译综述

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang yan Li Libo Chen Handong Jiao Zhijing yu Jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Semiconductor doping