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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

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

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

Gradient‑Layered MXene/Hollow Lignin nanospheres Architecture Design for Flexible and Stretchable Supercapacitors

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nano-Micro Letters 2025年第2期17卷 447-462页

作者： Haonan Zhang Cheng Hao Tongtong Fu Dian yu Jane Howe Kaiwen Chen ning yan Hao Ren Huamin Zhai Jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLnPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLnPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLnPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang nan Zheng Qingming Lin.yan You Zheng Gong yangping Zhuang Jiali Wu yu Wang Hanlin Huang Jun Ke Feng Chen Shengli Clinical Medical College of Fujian Medical University Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

miRnA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu yan yu Xiao-Li Li Xiao-Ting Sun Li-Ting Wang Xia Wu Ling-Jie Zhu Xiao-Jia yang Qian-Ru He Fei Ding Hai-yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRnA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RnA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRnA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

Asymmetric interfacial engineering regulated charge distribution on Ru/ni-n-C sites for efficient hydrogen evolution reaction in alkaline and seawater electrolytes

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Science China Chemistry 2025年

作者： Rui yu Xi Cao Chen.yang Zhu Qingqing Chen Ziyi yan Binbin Jiang Junjie Mao Xianwen Wei Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes College of Chemistry and Materials ScienceAnhui Normal University Anhui Provincial Key Laboratory of Advanced Catalysis and Energy Materials School of Chemistry and Chemical Engineering Anqing Normal University School of Chemistry and Chemical Engineering Anhui University of Technology

Developing highly efficient and cost-effective electrocatalysts for hydrogen evolution reaction（HER） is grandly challenging in alkaline and alkaline seawater electrolytes. Herein, the asymmetric interfacial active sites with Ru nanoparticles and ni single atoms in Ru/ni-n-C were designed through a solvothermal-pyrolysis process. Constructing highly asymmetric interfacial active sites with a strong electron delocalization effect significantly improves HER kinetics. As expected, Ru/ni-n-C requires low overpotentials with around 20 mV at 10 mA cm-2and robust durability over 48 h in alkaline and alkaline seawater *** at 200 mA cm-2, the overpotentials are close to 100 mV in both above electrolytes for Ru/ni-n-C. Density function theory calculation results suggest that the asymmetric interface between Ru nanoparticle and ni-n-C could accelerate the dissociation of water molecules and modulate the hydrogen species, consequently improving the HER performances. This work opens a unique approach for constructing advanced materials for energy conversion.

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