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Preparation and tailoring electromagnetic shielding and microwave absorbing performance of Fe_(3)O_(4)modified activated carbon foam based on mesophase coal pitch pyrolysis foaming
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作者 GE Yuanyuan WANG Yuzhe +4 位作者 XU Guozhong ZHU Yaming YUAN Xia SHI Guimei ZHONG Xiangyun 《燃料化学学报(中英文)》 北大核心 2026年第1期120-134,共15页
The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D i... The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D interconnected pore structure was prepared through the high pressure pyrolysis of mesophase coal tar pitch.It is found that the 3D interconnected cellular pores of MPCF facilitate multiple reflections of electromagnetic waves,which results in the minimum reflection loss(RLmin)value of MPCF reaches-37.84 dB with the effective absorption bandwidth(EAB)of 5.44 GHz at a thickness of 2.70 mm,and the total average electromagnetic shielding effectiveness(SE_(T))under 3.00 mm thickness achieves 26.52 dB in X-band.Subsequently,MPCF is activated by KOH to obtain activated carbon foam(A-MPCF).The average SE_(T)of A-MPCF achieves 103.00 dB for abundant nanopores on the pore cell walls,which leads to a transition from the multiple reflections of electromagnetic waves on the walls to diffuse reflection.Unfortunately,the reflection coefficient(R)of A-MPCF increases from 0.78 to 0.90.To reduce the R value,Fe_(3)O_(4)/A-MPCF was fabricated via the in situ growth of nano Fe_(3)O_(4)on A-MPCF.Consequently,the R value of Fe_(3)O_(4)/A-MPCF was reduced from 0.90 to 0.74,whereas the MWA performance was only slightly decreased.This work proposes a simple strategy for simultaneously adjusting MWA and EMI shielding performances of materials. 展开更多
关键词 carbon foam microwave absorption electromagnetic interference shielding mesophase pitch
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Detection of co-phasing error in segmented mirror based on extended Young’s interferometry combined with Vision Transformer
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作者 LIU Yin-ling YAO Chi +3 位作者 OUYANG Shang-tao WAN Yi-rong CHEN Mo LI Bin 《中国光学(中英文)》 北大核心 2026年第1期205-218,共14页
Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the... Due to the inability of manufacturing a single monolithic mirror at the 10-meter scales,segmented mirrors have become indispensable tools in modern astronomical research.However,to match the imaging performance of the monolithic counterpart,the sub-mirrors must maintain precise co-phasing.Piston error critically degrades segmented mirror imaging quality,necessitating efficient and precise detection.To ad-dress the limitations that the conventional circular-aperture diffraction with two-wavelength algorithm is sus-ceptible to decentration errors,and the traditional convolutional neural networks(CNNs)struggle to capture global features under large-range piston errors due to their restricted local receptive fields,this paper pro-poses a method that integrates extended Young’s interference principles with a Vision Transformer(ViT)to detect piston error.By suppressing decentration error interference through two symmetrically arranged aper-tures and extending the measurement range to±7.95μm via a two-wavelength(589 nm/600 nm)algorithm.This approach exploits ViT’s self-attention mechanism to model global characteristics of interference fringes.Unlike CNNs constrained by local convolutional kernels,the ViT significantly improves sensitivity to inter-ferogram periodicity.The simulation results demonstrate that the proposed method achieves a measurement accuracy of 5 nm(0.0083λ0)across the range of±7.95μm,while maintaining an accuracy exceeding 95%in the presence of Gaussian noise(SNR≥15 dB),Poisson noise(λ≥9 photons/pixel),and sub-mirror gap er-ror(Egap≤0.2)interference.Moreover,the detection speed shows significant improvement compared to the cross-correlation algorithm.This study establishes an accurate,robust framework for segmented mirror error detection,advancing high-precision astronomical observation. 展开更多
关键词 segmented mirror co-phasing piston errors ViT Young’s interference principles
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Numerical Simulation Study on Aerodynamic Interference Characteristics of Overlapping Rotors in Heavy⁃Load eVTOL Aircraft
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作者 DU Siliang DENG Kai WANG Bo 《Transactions of Nanjing University of Aeronautics and Astronautics》 2026年第1期40-54,共15页
Focusing on the unclear mechanism of aerodynamic interference in overlapping rotors of heavy-load electric vertical take-off and landing(eVTOL)aircraft,this paper aims to reveal the aerodynamic interference characteri... Focusing on the unclear mechanism of aerodynamic interference in overlapping rotors of heavy-load electric vertical take-off and landing(eVTOL)aircraft,this paper aims to reveal the aerodynamic interference characteristics and flow field evolution laws of overlapping rotor configurations in hovering conditions through numerical simulation methods.The research method involves constructing a computational model for rotor flow fields and aerodynamic characteristics based on the Reynolds-averaged Navier-Stokes(RANS)equations and the Spalart-Allmaras(S-A)turbulence model.The dynamic simulation of rotor rotational motion was achieved by using the moving nested grid technology.The reliability of the computational method was ensured through the grid independence verification and the comparison with experimental data.The research results indicate that in overlapping rotor systems,rotorⅡexperiences a decrease in thrust,significant power fluctuations,and reduced hovering efficiency due to continuous interference from the adjacent rotor’s wake and blade-vortex interactions.Blade-tip vortices undergo breakage,fusion,and secondary rolling in the overlapping region,forming large-scale turbulent structures that lead to attenuation of the induced velocity field and aerodynamic efficiency losses.Additionally,the interaction between the rotor downwash and the fuselage triggers a“fountain effect”and a sudden increase in surface pressure on the fuselage,exacerbating flow field distortion.Based on the aforementioned mechanisms,the safe flight of overlapping rotor configurations can be achieved by optimizing the configuration strategy of the rotational speed phase difference between adjacent blades.This study provides a theoretical basis for the rotor layout design and the aerodynamic performance enhancement of heavy-load eVTOL aircraft. 展开更多
关键词 electric vertical takeoff and landing(eVTOL)aircraft overlapping rotors aerodynamic interference numerical simulation rotor vortex interference
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Beyond the surface:Advancing neurorehabilitation with transcranial temporal interference stimulation——clinical applications and future prospects
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作者 Camille E.Proulx Friedhelm C.Hummel 《Neural Regeneration Research》 2026年第5期1987-1988,共2页
Brain lesions,such as those caused by stroke or traumatic brain injury(TBI),frequently result in persistent motor and cognitive impairments that significantly affect the individual patient's quality of life.Despit... Brain lesions,such as those caused by stroke or traumatic brain injury(TBI),frequently result in persistent motor and cognitive impairments that significantly affect the individual patient's quality of life.Despite differences in the mechanisms of injury,both conditions share a high prevalence of motor and cognitive impairments.These deficits show only limited natural recovery. 展开更多
关键词 NEUROREHABILITATION STIMULATION TRANSCRANIAL TEMPORAL INTERFERENCE motor cognitive impairments brain lesionssuch motor cognitive impairmentsthese
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Dual-Gradient Impedance/Insulation Structured Polyimide Nonwoven Fabric for Multi-Band Compatible Stealth
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作者 Xinwei Tang Wei Hong +8 位作者 Hongmiao Gao Shuangshuang Li Wei Li Kaixin Lai Mingzhen Xu Zaiyin Hu Yan Li Zicheng Wang Tianxi Liu 《Nano-Micro Letters》 2026年第4期621-637,共17页
Designing and preparing a compatible electromagnetic interference(EMI)shielding,radar and infrared stealth material exhibits significant prospect in the military field.Hence,a novel conductive/magnetic polyimide-based... Designing and preparing a compatible electromagnetic interference(EMI)shielding,radar and infrared stealth material exhibits significant prospect in the military field.Hence,a novel conductive/magnetic polyimide-based nonwoven fabric(PFN_y)is prepared by alkali treatment,Fe~(3+)ion exchange,thermal reduction,and electroless nickel(Ni)plating process.Its impedance/insulation characteristics can be easily adjusted by controlling the in situ growth of Fe_(3)O_(4) and electroless nickel plating.Subsequently,a new strategy of constructing hierarchical dual-gradient impedance/insulation structure is implemented to achieve EMI shielding,radar and infrared stealth via stacking PFN_y with gradually decreased impedance/insulation characteristics from top to bottom.The formation of impedance matching gradient structure promotes effective introduction and dissipation of electromagnetic waves,endowing the composite with outstanding EMI shielding and radar stealth performance.Meanwhile,the construction of thermal insulation gradient structure can effectively inhibit thermal radiation from target,bringing an excellent infrared stealth performance.Importantly,the strong interfacial interactions between Fe_(3)O_(4),Ni and polyimide fiber accelerate PFNy to resist the stresses originated from high-temperature heat source,achieving a compatible high-temperature resistant radar/infrared stealth performance.Such excellent comprehensive properties endow it with a great potential in high-temperature military camouflage applications against enemy radar and infrared detection. 展开更多
关键词 POLYIMIDE Electroless plating Electromagnetic interference shielding Radar stealth Infrared stealth
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Ultrahigh Electromagnetic Interference Shielding and Integrated Thermal Sensing-encryption Enabled by a Honeycomb-inspired Multifunctional Foam
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作者 Shao-Peng Yu Ya Liu +4 位作者 Ming-Yu Hao Xin Zhang Xu Zhang Yi-Cheng Yuan Zhen-Xiu Zhang 《Chinese Journal of Polymer Science》 2026年第2期513-524,I0016,共13页
With the rapid development of intelligent electronic and military equipment,multifunctional flexible materials that integrat electromagnetic interference(EMI)shielding,temperature sensing,and information encryption ar... With the rapid development of intelligent electronic and military equipment,multifunctional flexible materials that integrat electromagnetic interference(EMI)shielding,temperature sensing,and information encryption are urgently required.This study presents a bio-inspired hierarchical composite foam fabricated using supercritical nitrogen foaming technology.This material exhibits a honeycomb structure,with pore cell sizes controllable within a range of 30–92μm by regulating the filler.The carbon fiber felt(CFf)provides efficient reflection of electromagnetic waves,while the chloroprene rubber/carbon fiber/carbon black foam facilitates both wave absorption and temperature monitoring through its optimized conductive network.This synergistic mechanism results in an EMI shielding effectiveness(SE)of 60.06 d B with excellent temperature sensing performance(The temperature coefficient of resistance(TCR)is-2.642%/℃)in the 24–70℃ range.Notably,the material has a thermal conductivity of up to 0.159 W/(m·K),and the bio-inspired layered design enables information encryption,demonstrating the material's potential for secure communication applications.The foam also has tensile properties of up to 5.13 MPa and a tear strength of 33.02 N/mm.This biomimetic design overcomes the traditional limitations of flexible materials and provides a transformative solution for next-generation applications such as flexible electronics,aerospace systems and military equipment,which urgently need integrated electromagnetic protection,thermal management and information security. 展开更多
关键词 FLEXIBILITY Cellular structures Electromagnetic interference shielding Temperature sensor Message encryption
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Highly Elastic and Conductive Lamellar Wood Sponge via Cell Wall Reconfiguration Toward Smart Multifunctional Applications
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作者 Xin-jian Dai Xin Wang +2 位作者 Ji-hang Hu Pan Jiang Xiao-qing Wang 《Nano-Micro Letters》 2026年第5期798-815,共18页
Three-dimensional porous foams and aerogels with high compressibilityand elasticity hold great promise for applications in pressure sensing,electromagnetic interference(EMI)shielding,and thermal insulation.However,the... Three-dimensional porous foams and aerogels with high compressibilityand elasticity hold great promise for applications in pressure sensing,electromagnetic interference(EMI)shielding,and thermal insulation.However,their widespread application is often hindered by compromised structural stabilityand inadequate fatigue resistance under repeated compression.Herein,asustainable“top-down”cell wall reconfiguration strategy is proposed to fabricatehighly elastic,fatigue-resistant,and electrically conductive lamellar wood spongefrom natural balsa wood.This strategy involves the conversion of the intrinsiccellular structure of wood into an arch-shaped lamellar architecture reinforcedby chemical cross-linking,followed by coating the lamellar scaffold with conductivepolypyrrole(PPy)via in situ polymerization.The resulting PPy-coatedcross-linked wood sponge(CWS@PPy)demonstrates reversible compressibility,excellent fatigue resistance(∼3.5%plastic deformation after 10,000 cyclesat 40%strain).The strain-induced conductivity changes in CWS@PPy enabletunable EMI shielding effectiveness under cyclic compression and also facilities high-sensitivity pressure sensing(0.72 kPa^(-1)).Additionally,CWS@PPy exhibits a low through-plane thermal conductivity of 0.037 W m^(-1)K^(-1),which can be dynamically tuned for adaptivethermal management.The proposed mechanically robust and conductive wood sponge provides a versatile and sustainable platform fornext-generation smart devices. 展开更多
关键词 Cell wall reconfiguration Wood sponge Electromagnetic interference shielding Thermal management Pressure sensing
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Second-order correlated interference with multi-wavelength thermal-light beams
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作者 De-Sheng Wang Yi-Ning Zhao +5 位作者 Lingxin Kong Su-Heng Zhang Chong Wang Cheng Ren Yuehua Su De-Zhong Cao 《Chinese Physics B》 2026年第2期374-382,共9页
A method for correlating thermal light over a wide spectral range is proposed.A multi-wavelength pseudothermal source,prepared by projecting laser beams of multiple wavelengths(650 nm,635 nm,532 nm,and 473 nm)onto a m... A method for correlating thermal light over a wide spectral range is proposed.A multi-wavelength pseudothermal source,prepared by projecting laser beams of multiple wavelengths(650 nm,635 nm,532 nm,and 473 nm)onto a moving thin ground glass plate,is employed in a double-slit interference experiment.The ground glass plate induces random phase differences between light beams of different wavelengths passing through it.This initial random phase difference significantly influences the high-order intensity correlation functions of multi-wavelength thermal beams.Experimentally,second-order correlated interference patterns,including subwavelength interference,of pseudothermal beams with different wavelengths are observed in the intensity correlation measurements.This method facilitates applications of correlated thermal photons in quantum information processing and quantum imaging. 展开更多
关键词 correlated interference multi-wavelength thermal light second-order correlation function
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Optical temporal interference model for investigation and manipulation of non-integer high-order harmonic generation
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作者 Zhao-Yue Meng Yun Pan +1 位作者 Jun-Ping Wang Xi Zhao 《Chinese Physics B》 2026年第2期433-441,共9页
High-precision optical frequency measurement serves as a cornerstone of modern science and technology,enabling advancements in fields ranging from fundamental physics to quantum information technologies.Obtaining prec... High-precision optical frequency measurement serves as a cornerstone of modern science and technology,enabling advancements in fields ranging from fundamental physics to quantum information technologies.Obtaining precise photon frequencies,especially in the ultraviolet or even extreme ultraviolet regimes,is a key goal in both light–matter interaction experiments and engineering applications.High-order harmonic generation(HHG)is an ideal light source for producing such photons.In this work,we propose an optical temporal interference model(OTIM)that establishes an analogy with multi-slit Fraunhofer diffraction(MSFD)to manipulate fine-frequency photon generation by exploiting the temporal coherence of HHG processes.Our model provides a unified physical framework for three distinct non-integer HHG generation schemes:single-pulse,shaped-pulse,and laser pulse train approaches,which correspond to single-MSFD-like,double-MSFD-like,and multi-MSFD-like processes,respectively.Arbitrary non-integer HHG photons can be obtained using our scheme.Our approach provides a new perspective for accurately measuring and controlling photon frequencies in fields such as frequency comb technology,interferometry,and atomic clocks. 展开更多
关键词 high-order harmonic generation optical temporal interference multi-slit Fraunhofer diffraction
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Suppression of Dry-Coupled Rubber Layer Interference in Ultrasonic Thickness Measurement:A Comparative Study of Empirical Mode Decomposition Variants
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作者 Weichen Wang Shaofeng Wang +4 位作者 Wenjing Liu Luncai Zhou Erqing Zhang Ting Gao Grigory Petrishin 《Structural Durability & Health Monitoring》 2026年第1期302-316,共15页
In dry-coupled ultrasonic thickness measurement,thick rubber layers introduce high-amplitude parasitic echoes that obscure defect signals and degrade thickness accuracy.Existing methods struggle to resolve overlap-pin... In dry-coupled ultrasonic thickness measurement,thick rubber layers introduce high-amplitude parasitic echoes that obscure defect signals and degrade thickness accuracy.Existing methods struggle to resolve overlap-ping echoes under variable coupling conditions and non-stationary noise.This study proposes a novel dual-criterion framework integrating energy contribution and statistical impulsivity metrics to isolate specimen re-flections from coupling-layer interference.By decomposing A-scan signals into Intrinsic Mode Functions(IMFs),the framework employs energy contribution thresholds(>85%)and kurtosis indices(>3)to autonomously select IMFs containing valid specimen echoes.Hybrid time-frequency thresholding further suppresses interference through amplitude filtering and spectral focusing.Experimental results demonstrate the framework’s robustness,achieving 92.3%thickness accuracy for 5 mm steel specimens with 5 mm rubber coupling,outperforming conventional methods by up to 18.7%.The dual-criterion approach reduces operator dependency by 37%and maintainsΔT<0.03 mm under surface roughness up to 6.3μm,offering a practical solution for industrial nondestructive testing with thick dry-coupled interfaces. 展开更多
关键词 Empirical mode decomposition complete ensemble EMD with adaptive noise(CEEMDAN) dry-coupled ultrasonic testing thickness measurement signal interference suppression
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Metal-based nanomedicines for cancer theranostics
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作者 Hai-Jia Yu Jian-Hua Liu +6 位作者 Wei Liu Rui Niu Bin Zhang Yuan Xiong Yang Liu Ying-Hui Wang Hong-Jie Zhang 《Military Medical Research》 2026年第1期78-128,共51页
The heterogeneity and invasiveness of cancer cells pose serious challenges in cancer diagnosis and treatment.Advancements and innovations in metal-based nanomedicines provide novel avenues for addressing these challen... The heterogeneity and invasiveness of cancer cells pose serious challenges in cancer diagnosis and treatment.Advancements and innovations in metal-based nanomedicines provide novel avenues for addressing these challenges.Metal-based nanomedicines possess unique physicochemical properties that enable their interaction with living organisms,thereby inducing complex biological responses.These nanomaterials have been extensively used to enhance the contrast and sensitivity of cancer imaging and to amplify the distinction between cancerous and healthy tissues.Moreover,these nanomaterials can effectively combat a wide spectrum of cancers through various methods,including drug delivery,radiotherapy,photothermal therapy(PTT),photodynamic therapy(PDT),sonodynamic therapy(SDT),biocatalytic therapy,ion interference therapy(IIT),and immunotherapy.Currently,there is still a need for a comprehensive summary on the metal-based nanomaterials for cancer diagnosis and treatment.Herein,we present a systematic and complete overview of action mechanisms and the applications of metal-based nanomaterials in cancer theranostics.A summary of common strategies for synthesizing and modifying metal-based nanomedicines is presented,and their biosafety is analyzed.Then,the latest developments in their applications for cancer imaging and anticancer treatment are provided.Finally,the key technical challenges and reasonable perspectives of metal-based nanomedicines for cancer theranostics in clinical applications are discussed. 展开更多
关键词 Metal-based nanomedicines Synthesis strategy Computed tomography(CT)imaging Nuclear imaging Magnetic resonance imaging(MRI) Fluorescence(FL)imaging Photoacoustic imaging(PAI) DRUG-DELIVERY Phototherapy Catalytic therapy Ion interference therapy(IIT) Immunotherapy
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Multifunctional Nacre‑Like Nanocomposite Papers for Electromagnetic Interference Shielding via Heterocyclic Aramid/MXene Template‑Assisted In‑Situ Polypyrrole Assembly 被引量:1
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作者 Jinhua Xiong Xu Zhao +6 位作者 Zonglin Liu He Chen Qian Yan Huanxin Lian Yunxiang Chen Qingyu Peng Xiaodong He 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期37-54,共18页
Robust, ultra-flexible, and multifunctional MXene-basedelectromagnetic interference (EMI) shielding nanocomposite filmsexhibit enormous potential for applications in artificial intelligence,wireless telecommunication,... Robust, ultra-flexible, and multifunctional MXene-basedelectromagnetic interference (EMI) shielding nanocomposite filmsexhibit enormous potential for applications in artificial intelligence,wireless telecommunication, and portable/wearable electronic equipment.In this work, a nacre-inspired multifunctional heterocyclic aramid(HA)/MXene@polypyrrole (PPy) (HMP) nanocomposite paper withlarge-scale, high strength, super toughness, and excellent tolerance tocomplex conditions is fabricated through the strategy of HA/MXenehydrogel template-assisted in-situ assembly of PPy. Benefiting from the"brick-and-mortar" layered structure and the strong hydrogen-bondinginteractions among MXene, HA, and PPy, the paper exhibits remarkable mechanical performances, including high tensile strength (309.7 MPa),outstanding toughness (57.6 MJ m−3), exceptional foldability, and structural stability against ultrasonication. By using the template effect ofHA/MXene to guide the assembly of conductive polymers, the synthesized paper obtains excellent electronic conductivity. More importantly,the highly continuous conductive path enables the nanocomposite paper to achieve a splendid EMI shielding effectiveness (EMI SE) of 54.1 dBat an ultra-thin thickness (25.4 μm) and a high specific EMI SE of 17,204.7 dB cm2g−1. In addition, the papers also have excellent applicationsin electromagnetic protection, electro-/photothermal de-icing, thermal therapy, and fire safety. These findings broaden the ideas for developinghigh-performance and multifunctional MXene-based films with enormous application potential in EMI shielding and thermal management. 展开更多
关键词 MXene Remarkable mechanical properties Heterocyclic aramid Electromagnetic interference shielding POLYPYRROLE Multifunctionality
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Multistage microcellular waterborne polyurethane composite with optionally low-reflection behavior for ultra-efficient electromagnetic interference shielding 被引量:5
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作者 Jianming Yang Hu Wang +4 位作者 Hexin Zhang Peng Lin Hong Gao Youyi Xia Xia Liao 《Journal of Materials Science & Technology》 2025年第5期132-140,共9页
Electromagnetic interference(EMI)shielding materials with superior shielding efficiency and low-reflection properties hold promising potential for utilization across electronic components,precision instruments,and fif... Electromagnetic interference(EMI)shielding materials with superior shielding efficiency and low-reflection properties hold promising potential for utilization across electronic components,precision instruments,and fifth-generation communication equipment.In this study,multistage microcellular waterborne polyurethane(WPU)composites were constructed via gradient induction,layer-by-layer casting,and supercritical carbon dioxide foaming.The gradient-structured WPU/ironcobalt loaded reduced graphene oxide(FeCo@rGO)foam serves as an impedance-matched absorption layer,while the highly conductive WPU/silver loaded glass microspheres(Ag@GM)layer is employed as a reflection layer.Thanks to the incorporation of an asymmetric structure,as well as the introduction of gradient and porous configurations,the composite foam demonstrates excellent conductivity,outstanding EMI SE(74.9 dB),and minimal reflection characteristics(35.28%)in 8.2-12.4 GHz,implying that more than 99.99999%of electromagnetic(EM)waves were blocked and only 35.28%were reflected to the external environment.Interestingly,the reflectivity of the composite foam is reduced to 0.41%at 10.88 GHz due to the resonance for incident and reflected EM waves.Beyond that,the composite foam is characterized by low density(0.47 g/cm^(3))and great stability of EMI shielding properties.This work offers a viable approach for craft-ing lightweight,highly shielding,and minimally reflective EMI shielding composites. 展开更多
关键词 Electromagnetic interference shielding Supercritical carbon dioxide(ScCO_(2))foaming Low reflectivity Multilayered structure MICROCELLULAR
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Improving DOA estimation of GNSS interference through sparse non-uniform array reconfiguration 被引量:3
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作者 Rongling LANG Hao XU +3 位作者 Fei GAO Zewen TANG Zhipeng WANG Amir HUSSAIN 《Chinese Journal of Aeronautics》 2025年第8期104-118,共15页
Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capa... Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capabilities.The Uniform Circular Array(UCA)enables concurrent estimation of the Direction of Arrival(DOA)in both azimuth and elevation.Given the paramount importance of stability and real-time performance in interference localization,this work proposes an innovative approach to reduce the complexity and increase the robustness of the DOA estimation.The proposed method reduces computational complexity by selecting a reduced number of array elements to reconstruct a non-uniform sparse array from a UCA.To ensure DOA estimation accuracy,minimizing the Cramér-Rao Bound(CRB)is the objective,and the Spatial Correlation Coefficient(SCC)is incorporated as a constraint to mitigate side-lobe.The optimization model is a quadratic fractional model,which is solved by Semi-Definite Relaxation(SDR).When the array has perturbations,the mathematical expressions for CRB and SCC are re-derived to enhance the robustness of the reconstructed array.Simulation and hardware experiments validate the effectiveness of the proposed method in estimating interference DOA,showing high robustness and reductions in hardware and computational costs associated with DOA estimation. 展开更多
关键词 GNSS interference location Direction of arrival estimation Adaptive reconfigurable array Cramér-Raobound Quadratic fractional programming
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Janus structure design of polyimide composite foam for absorption-dominated EMI shielding and thermal insulation 被引量:2
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作者 Ruixing Hao Yaqi Yang +3 位作者 Peiyou He Yaqing Liu Guizhe Zhao Hongji Duan 《Journal of Materials Science & Technology》 2025年第3期317-326,共10页
In the present work,by virtue of the synergistic and independent effects of Janus structure,an asymmetric nickel-chain/multiwall carbon nanotube/polyimide(Ni/MWCNTs/PI)composite foam with absorption-dominated electrom... In the present work,by virtue of the synergistic and independent effects of Janus structure,an asymmetric nickel-chain/multiwall carbon nanotube/polyimide(Ni/MWCNTs/PI)composite foam with absorption-dominated electromagnetic interference(EMI)shielding and thermal insulation performances was successfully fabricated through an ordered casting and directional freeze-drying strategy.Water-soluble polyamic acid(PAA)was chosen to match the oriented freeze-drying method to acquire oriented pores,and the thermal imidization process from PAA to PI exactly eliminated the interface of the multilayered structure.By controlling the electro-magnetic gradient and propagation path of the incident microwaves in the MWCNT/PI and Ni/PI layers,the PI composite foam exhibited an efficient EMI SE of 55.8 dB in the X-band with extremely low reflection characteristics(R=0.22).The asymmetric conductive net-work also greatly preserved the thermal insulation properties of PI.The thermal conductivity(TC)of the Ni/MWCNT/PI composite foam was as low as 0.032 W/(m K).In addition,owing to the elimination of MWCNT/PI and Ni/PI interfaces during the thermal imidization process,the composite foam showed satisfactory compressive strength.The fabricated PI composite foam could provide reliable electromagnetic protection in complex applications and withstand high temperatures,which has great potential in cuttingedge applications such as advanced aircraft. 展开更多
关键词 Electromagnetic interference shielding(EMI) Thermal insulation POLYIMIDE Janus structure Low reflection
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Failure mechanisms of electronic detonators subjected to high impact loading in rock drilling and blasting 被引量:2
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作者 Zhendong Leng Yong Fan +2 位作者 Wenbo Lu Qidong Gao Guangdong Yang 《International Journal of Coal Science & Technology》 2025年第1期214-227,共14页
In rock drilling and blasting,the misfire of electronic detonators will not only affect the rock fragmentation result but also bring serious potential safety hazards to engineering construction.An accurate and compreh... In rock drilling and blasting,the misfire of electronic detonators will not only affect the rock fragmentation result but also bring serious potential safety hazards to engineering construction.An accurate and comprehensive understanding of the failure mechanisms of electronic detonators subjected to impact loading is of great significance to the reliability design and field safety use of electronic detonators.The spatial distribution characteristics and failure modes of misfired electronic detonators under different application scenarios are statistically analysed.The results show that under high impact loads,electronic detonators will experience failure phenomena such as rupture of the fuse head,fracture of the bridge wire,falling off of the solder joint,chip module damage and insufficient initiation energy after deformation.The lack of impact resistance is the primary cause of misfire of electronic detonators.Combined with the underwater impact resistance test and the impact load test in the adjacent blasthole on site,the formulas of the impact failure probability of the electronic detonator under different stress‒strength distribution curves are deduced.The test and evaluation method of the impact resistance of electronic detonators based on stress‒strength interference theory is proposed.Furthermore,the impact failure model of electronic detonators considering the strength degradation effect under repeated random loads is established.On this basis,the failure mechanism of electronic detonators under different application environments,such as open-pit blasting and underground blasting,is revealed,which provides scientific theory and methods for the reliability analysis,design and type selection of electronic detonators in rock drilling and blasting. 展开更多
关键词 Rock blasting Electronic detonator Impact loading Stress‒strength interference theory Strength degradation effect
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Hierarchical Polyimide Nonwoven Fabric with Ultralow-Reflectivity Electromagnetic Interference Shielding and High-Temperature Resistant Infrared Stealth Performance 被引量:1
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作者 Xinwei Tang Yezi Lu +7 位作者 Shuangshuang Li Mingyang Zhu Zixuan Wang Yan Li Zaiyin Hu Penglun Zheng Zicheng Wang Tianxi Liu 《Nano-Micro Letters》 2025年第4期111-129,共19页
Designing and fabricating a compatible low-reflectivity electromagnetic interference(EMI)shielding/high-temperature resistant infrared stealth material possesses a critical significance in the field of military.Hence,... Designing and fabricating a compatible low-reflectivity electromagnetic interference(EMI)shielding/high-temperature resistant infrared stealth material possesses a critical significance in the field of military.Hence,a hierarchical polyimide(PI)nonwoven fabric is fabricated by alkali treatment,in-situ growth of magnetic particles and"self-activated"electroless Ag plating process.Especially,the hierarchical impedance matching can be constructed by systematically assembling Fe_(3)O_(4)/Ag-loaded PI nonwoven fabric(PFA)and pure Ag-coated PI nonwoven fabric(PA),endowing it with an ultralowreflectivity EMI shielding performance.In addition,thermal insulation of fluffy three-dimensional(3D)space structure in PFA and low infrared emissivity of PA originated from Ag plating bring an excellent infrared stealth performance.More importantly,the strong bonding interaction between Fe_(3)O_(4),Ag,and PI fiber improves thermal stability in EMI shielding and high-temperature resistant infrared stealth performance.Such excellent comprehensive performance makes it promising for military tents to protect internal equipment from electromagnetic interference stemmed from adjacent equipment and/or enemy,and inhibit external infrared detection. 展开更多
关键词 POLYIMIDE Electromagnetic interference shielding Low reflectivity Infrared stealth Compatibility
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Learning Based Interference Coordination for Maritime Communications 被引量:1
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作者 Liu Chuhuan Xiao Liang +3 位作者 Chen Yifan Li Siyao Yang Helin Lyu Zefang 《China Communications》 2025年第4期356-374,共19页
With the boom in maritime activities,the need for highly reliable maritime communication is becoming urgent,which is an important component of 5G/6G communication networks.However,the bandwidth reuse characteristic of... With the boom in maritime activities,the need for highly reliable maritime communication is becoming urgent,which is an important component of 5G/6G communication networks.However,the bandwidth reuse characteristic of 5G/6G networks will inevitably lead to severe interference,resulting in degradation in the communication performance of maritime users.In this paper,we propose a safe deep reinforcement learning based interference coordination scheme to jointly optimize the power control and bandwidth allocation in maritime communication systems,and exploit the quality-of-service requirements of users as the risk value references to evaluate the communication policies.In particular,this scheme designs a deep neural network to select the communication policies through the evaluation network and update the parameters using the target network,which improves the communication performance and speeds up the convergence rate.Moreover,the Nash equilibrium of the interference coordination game and the computational complexity of the proposed scheme are analyzed.Simulation and experimental results verify the performance gain of the proposed scheme compared with benchmarks. 展开更多
关键词 bandwidth allocation interference coordination maritime communication power control rein-forcement learning
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Drug development for chronic hepatitis B functional cure:Recent progress 被引量:1
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作者 Ting Liu He Wang +3 位作者 Yue Zhao Ying-Xin Wang Xue Xing Peng Gao 《World Journal of Hepatology》 2025年第4期31-42,共12页
Chronic hepatitis B virus(HBV)infection affects approximately 254 million individuals globally,contributing to significant morbidity and mortality due to HBV-related liver failure and cirrhosis,which result in million... Chronic hepatitis B virus(HBV)infection affects approximately 254 million individuals globally,contributing to significant morbidity and mortality due to HBV-related liver failure and cirrhosis,which result in millions of fatalities each year.Although approved antiviral nucleos(t)ide analogues can effectively suppress HBV replication,their ability to reduce hepatitis B surface antigen(HBsAg)levels in plasma remains limited.The clinical application of the immunomodulator interferon-alpha is restricted by concerns regarding its safety and the severity of associated adverse reactions,rendering long-term administration challenging.Therefore,current drug development efforts for chronic hepatitis B aim to achieve a functional cure,which is defined as HBsAg serological clearance and sustained suppression of HBV DNA.This review discusses recent advancements in novel direct-acting therapeutic strategies for the treatment of chronic hepatitis B by focusing on the progresses in HBV entry inhibitors,monoclonal antibodies,RNA interferences,and other agents that directly target the virus.Furthermore,we discuss the development of immunomodulatory therapies,including TLR-7/8 agonists,immune checkpoint inhibitors,and therapeutic vaccines.In the end,we conclude by highlighting the importance of the rational combination-strategy design to improve the functional cure rate of HBV. 展开更多
关键词 Chronic hepatitis B infection Therapeutic targets Monoclonal antibody RNA interference IMMUNOMODULATORS
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Overexpression of Tu ABCC4 is associated with abamectin resistance in Tetranychus urticae Koch 被引量:1
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作者 Mingmei Wu Rui Dong +6 位作者 Yan Zhang Haojie Liao Tian Tian Dandan Xu Youjun Zhang Zhaojiang Guo Shaoli Wang 《Journal of Integrative Agriculture》 2025年第6期2299-2310,共12页
Pesticide resistance greatly limits control efficacy after the long-term application of pesticides.The two-spottedspider mite,Tetranychus urticae Koch,is a notorious agricultural pest worldwide that is resistant to va... Pesticide resistance greatly limits control efficacy after the long-term application of pesticides.The two-spottedspider mite,Tetranychus urticae Koch,is a notorious agricultural pest worldwide that is resistant to various pesticides,including abamectin.While some studies of abamectin resistance have investigated target resistance related toglutamate-gated chloride channels(GluCls),studies on the metabolic resistance mechanisms are still limited.In this study,we identified an ABCC subfamily gene,Tu ABCC4,that was overexpressed in resistant populations of T.urticae,based on the analysis of previously obtained transcriptomic and RNA-seq data.No consistent nonsynonymousmutations in the Tu ABCC4 gene were found between the susceptible and resistant populations,although Tu ABCC4expression was significantly increased in all the resistant populations that were studied.Synergistic experiments withthe inhibitor verapamil and gene expression analysis of the susceptible and resistant populations confirmed the key roleof Tu ABCC4 in abamectin resistance.In addition,an increase in the expression of the Tu ABCC4 gene was shown byRNA interference and genetic association analysis to be closely related to the resistance of T.urticae to abamectin.Inconclusion,overexpression of Tu ABCC4 was shown to be involved in abamectin resistance in T.urticae.These resultscan help us to better understand the molecular basis of pest resistance to abamectin. 展开更多
关键词 Tetranychus urticae ABC transporter gene resistance mechanism RNA interference genetic associationanalysis
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