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Artificial intelligence-enabled high-precision colony extraction and isolation system
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作者 ZHAO Xu-feng JIA Zhi-qiang +5 位作者 CHEN Wei-xue HU Peng-tao SU Xin-ran LI Jun-lin GE Ming-feng DONG Wen-fei 《中国光学(中英文)》 北大核心 2026年第1期190-204,共15页
Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and... Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel. 展开更多
关键词 artificial intelligence colony extraction and isolation large-field imaging AUTOMATION
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Joint Associations of Sarcopenia and Social Isolation with Mortality:Two Prospective Cohort Studies across Different Cultural Contexts
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作者 Juanjuan Li Zhe Zhang +6 位作者 Jijuan Zhang Yuxiang Wang Hancheng Yu Gang Liu An Pan Yunfei Liao Tingting Geng 《Biomedical and Environmental Sciences》 2026年第1期3-14,共12页
Objective This study aims to investigate the joint associations of sarcopenia and social isolation with mortality risk.Methods Using data from the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and the UK Biobank... Objective This study aims to investigate the joint associations of sarcopenia and social isolation with mortality risk.Methods Using data from the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and the UK Biobank,sarcopenia was diagnosed according to European and Asian Working Groups for Sarcopenia criteria.Social isolation was assessed using standardized questionnaires,including questions on solitude,frequency of social activities,contact with others,and marital status(for the CLHLS only).Results During the follow-up period,8,249 deaths occurred in the CLHLS and 26,670 deaths in the UK Biobank groups.While no significant interaction was observed between sarcopenia and social isolation in predicting all-cause mortality in the CLHLS cohort,the association between social isolation and mortality was stronger among individuals with sarcopenia in the UK Biobank(P-interaction=0.03,relative risk due to interaction:0.23,95%confidence interval[CI]:0.06–0.41).Further joint analyses showed that participants with sarcopenia and high levels of social isolation had the highest mortality risk(hazard ration[HR]:1.99;95%CI:[1.74–2.28]in the CLHLS and 1.69[1.55–1.85]in the UK Biobank)compared to those without either condition.Conclusion The combination of social isolation and sarcopenia synergistically increases the risk of mortality in middle-aged and older adults across diverse populations. 展开更多
关键词 SARCOPENIA Social isolation MORTALITY UK Biobank CLHLS
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Chitosan as oral absorption enhancer and inhibitor:A comprehensive review
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作者 Sajid Hussain Omer M.A.Dagah +8 位作者 Essam A.M.S Obaid Peng Jin Ovas Ahmed Dar Muhammd Irfan Yiming Qi Qinghua Wu Ming Jin Tengli Zhang Lei Luo 《Chinese Chemical Letters》 2026年第1期137-147,共11页
Chitosan(CS),a natural polymer derived from chitin found in the exoskeletons of crustaceans,has garnered significant interest in the pharmaceutical field due to its unique properties,including biocompatibility and bio... Chitosan(CS),a natural polymer derived from chitin found in the exoskeletons of crustaceans,has garnered significant interest in the pharmaceutical field due to its unique properties,including biocompatibility and biodegradability.In recent years,various studies have reported that CS can affect drug bioavailability,and interestingly,it works as an oral absorption enhancer and inhibitor.This review offers an in-depth analysis of the mechanisms underlying such a phenomenon and supports its application as a pharmaceutical excipient.CS enhances oral drug absorption through various mechanisms,such as interaction with the intestinal mucosa,tight junction modulation,inhibition of efflux transporters,enzyme inhibition,solubility and stability enhancement,and complexation.On the other side,CS exhibits the ability to inhibit the absorption of certain drugs by adsorbing to lipids and sterols,modulating bile acids and gut microbiota,altering drug-cell interaction at the polar interface,and mucus-mediated entrapment and interference.Future potential pharmaceutical research in this field includes elucidating the underneath absorption relevant mechanisms,rational use in formulations as excipient,exploring functional CS derivatives,and developing CS-based drug delivery systems.This comprehensive review highlights CS's versatile and significant role in enhancing and inhibiting oral drug absorption,providing insights into the complexities of drug delivery and the potential of CS to improve therapeutic outcomes. 展开更多
关键词 Oral absorption EXCIPIENTS CHITOSAN ENHANCER INHIBITOR
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Enhanced electromagnetic wave absorption in biochar/yttrium iron garnet hybrid composites for electromagnetic interference shielding applications
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作者 Ozgur Yasin Keskin 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期335-346,共12页
Biochar and biochar composites are versatile materials that can be used in many applications.In this study,biochar was prepared from sawdust and combined with the yttrium iron garnet(YIG)nanocrystal to investigate the... Biochar and biochar composites are versatile materials that can be used in many applications.In this study,biochar was prepared from sawdust and combined with the yttrium iron garnet(YIG)nanocrystal to investigate the shielding effectiveness of the composite structure.Firstly,the effect of the pyrolysis temperature on the shielding effectiveness of biochar was investigated.Secondly,biochars combined with YIG nanocrystals with different contents and shielding effectiveness of the composites were investigated.The electromagnetic effectiveness of the samples was investigated within the X band(8-12 GHz).The findings indicate that biochar demonstrates enhanced absorption properties with elevated pyrolysis temperatures.Biochars demonstrated an approximate 40 d B shielding effectiveness,while YIG exhibited approximately 7 d B,corresponding to absorption at 8 GHz.However,the combination of biochar and YIG exhibited exceptional absorption,reaching 67.12 d B at 8 GHz. 展开更多
关键词 BIOCHAR electromagnetic shielding electromagnetic wave absorption COMPOSITE
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Seismic performance of a new type of sliding-rolling friction composite isolation bearing
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作者 Liu Bo Pan Danguang +2 位作者 Song Congbo Liu Linlin Ni Guowei 《Earthquake Engineering and Engineering Vibration》 2026年第1期171-185,共15页
Isolation technology can reduce the type of structural damage that earthquakes cause.A new type of composite sliding-rolling friction composite seismic isolation bearing(SRF)with composite sliding friction and rolling... Isolation technology can reduce the type of structural damage that earthquakes cause.A new type of composite sliding-rolling friction composite seismic isolation bearing(SRF)with composite sliding friction and rolling friction is proposed.SRF is capable of realizing a parallel arrangement of sliding friction and rolling friction,and the coefficient of dynamic friction shows variability.The proposed static tests on composite bearings were conducted to investigate the effects of the number of shims,loading speed and vertical pressure on the dynamic friction factor.Test results show that the coefficient of dynamic friction first generally decreases and then increases with an increase in sliding speed,prior to again decreasing with an increase in vertical pressure.The dynamic friction factor increases and then decreases with an increase in the number of shims for a four-roll ball.It decreases and then increases with an increase in the number of shims for a five-roll ball.Based on finite element analysis,modeling and analyzing the effects of the coefficient of friction,the number of balls and the number of shims on the hysteresis performance of the support and derive its skeleton curve.The SRF hysteretic performance,dynamic friction factor and the number of rolling balls and shims show significant correlation. 展开更多
关键词 sliding friction rolling friction isolation bearing friction coefficient hysteresis performance
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Whole genome sequencing analysis reveals strong reproductive isolation between two hybridizing Rhododendron species in subgenus Tsutsusi
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作者 Xiaoling Tian Ningning Zhang +5 位作者 Xiaohua Li Zhong Zhang Heng Shu Chunying Zhang Yongpeng Ma Yupeng Geng 《Plant Diversity》 2026年第1期212-215,共4页
Natural hybridization is known to play a vital role in speciation;however,the mechanisms underlying the early stages of natural hybridization remain unclear.Where two plant species come into contact,two driving forces... Natural hybridization is known to play a vital role in speciation;however,the mechanisms underlying the early stages of natural hybridization remain unclear.Where two plant species come into contact,two driving forces may balance the dynamic consequences of hybridization:fusion by hybridization-mediated gene flow,and separation by reproductive isolation(RI)(Ma et al.,2010a,b;Chang et al.,2022). 展开更多
关键词 Reproductive isolation Natural hybridization RHODODENDRON Mutation load Whole genome sequence
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一种融合Isolation Forest的改进AdaBoost算法
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作者 杨超凡 杜月寒 +1 位作者 吴冠鹏 罗房房 《电脑知识与技术》 2026年第1期32-34,共3页
AdaBoost算法是一种能有效提升弱分类器性能的集成学习方法,在二分类任务中表现出卓越的性能。然而,经典的AdaBoost算法对噪声数据高度敏感,导致分类性能下降。为了解决该问题,文章提出一种基于Isolation Forest(iForest)的改进AdaBoos... AdaBoost算法是一种能有效提升弱分类器性能的集成学习方法,在二分类任务中表现出卓越的性能。然而,经典的AdaBoost算法对噪声数据高度敏感,导致分类性能下降。为了解决该问题,文章提出一种基于Isolation Forest(iForest)的改进AdaBoost算法。该方法在AdaBoost的每次迭代中,利用i Forest在被错误分类的样本中识别并剔除离群点。此举将使后续的弱分类器聚焦于学习那些具有代表性的“困难”样本,从而避免模型性能因噪声干扰而下降。在多个公开数据集上的实验结果表明,所提算法在AUC指标上显著优于经典的AdaBoost、AdaCost及LogitBoost算法。 展开更多
关键词 弱分类器 集成学习 ADABOOST isolation Forest 离群点
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Solid 226 nm laser pumped by a Nd:YAG laser for two-photon absorption detection of oxygen
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作者 Yi Zhang Shaoyi Wang +2 位作者 Minghao Yu Zhongqi Feng Dacheng Zhang 《Advanced Photonics Nexus》 2026年第1期82-87,共6页
We present a solid 226 nm deep ultraviolet laser system pumped by a Nd:YAG laser.A diamond Raman laser with a 1485 nm wavelength was generated up to 2.53 mJ pumped by a 9.7 mJ 1064 nm laser,which is the highest pulse ... We present a solid 226 nm deep ultraviolet laser system pumped by a Nd:YAG laser.A diamond Raman laser with a 1485 nm wavelength was generated up to 2.53 mJ pumped by a 9.7 mJ 1064 nm laser,which is the highest pulse energy of a second Stokes diamond Raman laser pumped by a 1064 nm laser as we know.Then,the Raman laser is mixed with the frequency-quadrupled 1064 nm laser to produce the 226 nm laser.The maximum output pulse energy at 226 nm reaches 0.49 mJ.The overall conversion efficiency from1064 to 226 nm is up to 1.14%,which is significantly higher than conventional optical parametric oscillator technology for the generation of 226 nm laser.The 226 nm laser system has been used in a laser-induced fluorescence(LIF)experiment of oxygen two-photon to demonstrate its potential for LIF measurements. 展开更多
关键词 Raman laser deep ultraviolet laser-induced fluorescence SUM-FREQUENCY two-photon absorption
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Energy absorption behavior of mild steel tube-core sandwich structures for rockfall protection
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作者 HUANG Fuyou ZHANG Luqing +3 位作者 ZHOU Jian HAN Zhenhua WANG Song SUN Qihao 《Journal of Mountain Science》 2026年第1期171-187,共17页
Sandwich structures are widely favored for their lightweight,high strength and superior impact mitigation capabilities in blast mitigation and transportation safety applications.Their application in large-scale,high-e... Sandwich structures are widely favored for their lightweight,high strength and superior impact mitigation capabilities in blast mitigation and transportation safety applications.Their application in large-scale,high-energy rockfall protection remains limited due to their relatively low volumetric energy absorption efficiency and the complex fabrication processes of key energy-absorbing components.To address these limitations,this study proposes a novel sandwich structure incorporating mild steel tubes as core energy absorbers to efficiently mitigate highenergy rockfall impacts.A finite element model was developed in LS-DYNA to systematically investigate the deformation and energy absorption behaviors.Comprehensive parametric analyses were conducted to quantify the effects of key design variables,including tube wall thickness,tube spacing(number of tubes),and infill materials.The results demonstrate that increasing tube wall thickness significantly enhances ultimate energy absorption,with 12-mm-thick tubes absorbing 2.2 times more energy than 6-mm-thick tubes.Lateral constraints induced by adjacent tubes improve specific energy absorption per unit displacement by approximately 30%-45%.Furthermore,incorporating infill materials considerably enhances energy absorption,with aluminum foam infills achieving an 81%increase compared to empty tubes.Nevertheless,higher energy absorption capacity typically leads to greater peak impact forces,increasing the number of tubes offers a better balance between energy absorption and impact force,optimizing the structural performance.These findings provide valuable theoretical insights and practical guidelines for designing sandwich structures in civil and infrastructure engineering applications for effective rockfall protection. 展开更多
关键词 Sandwich structure Mild steel tube Rockfall impact Energy absorption Structural optimization
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A sustainable and high value-added strategy under lignite and waste silicon powder to construct SiC nanowires for electromagnetic wave absorption
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作者 Wenhao Wang Xiaolin Lan +6 位作者 Haoquan Hao Jingxiang Liu Yong Shuai Qinghe Jing Shouqing Yan Jie Guo Zhijiang Wang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期347-356,共10页
The electromagnetic wave absorption of silicon carbide nanowires is improved by their uniform and diverse cross-structures.This study introduces a sustainable and high value-added method for synthesizing silicon carbi... The electromagnetic wave absorption of silicon carbide nanowires is improved by their uniform and diverse cross-structures.This study introduces a sustainable and high value-added method for synthesizing silicon carbide nanowires using lignite and waste silicon powder as raw materials through carbothermal reduction.The staggered structure of nanowires promotes the creation of interfacial polarization,impedance matching,and multiple loss mechanisms,leading to enhanced electromagnetic absorption performance.The silicon carbide nanowires demonstrate outstanding electromagnetic absorption capabilities with the minimum reflection loss of-48.09 d B at10.08 GHz and an effective absorption bandwidth(the reflection loss less than-10 d B)ranging from 8.54 to 16.68 GHz with a thickness of 2.17 mm.This research presents an innovative approach for utilizing solid waste in an environmentally friendly manner to produce broadband silicon carbide composite absorbers. 展开更多
关键词 LIGNITE waste silicon powder SiC nanowires electromagnetic wave absorption high value-added
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Energy absorption characteristics of additively manufactured sea sponge-inspired lattice structures under low-velocity impact loading
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作者 J Jefferson Andrew Jabir Ubaid +4 位作者 Mohammed Ayaz Uddin Omar Waqas Saadi Kamran Ahmed Khan Rehan Umer Andreas Schiffer 《Defence Technology(防务技术)》 2026年第1期118-129,共12页
Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices,mimicking the architecture of the marine sponge organism Euplectella aspergillum.These sea sponge-ins... Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices,mimicking the architecture of the marine sponge organism Euplectella aspergillum.These sea sponge-inspired lattice structures feature a square-grid 2D lattice with double diagonal bracings and are additively manufactured via digital light processing(DLP).The collapse strength and energy absorption capacity of sea sponge lattice structures are evaluated under various impact conditions and are compared to those of their constituent square-grid and double diagonal lattices.This study demonstrates that sea sponge lattices can achieve an 11-fold increase in energy absorption compared to the square-grid lattice,due to the stabilizing effect of the double diagonal bracings prompting the structure to collapse layer-bylayer under impact.By adjusting the thickness ratio in the sea sponge lattice,up to 76.7%increment in energy absorption is attained.It is also shown that sea-sponge lattices outperform well-established energy-absorbing materials of equal weight,such as hexagonal honeycombs,confirming their significant potential for impact mitigation.Additionally,this research highlights the enhancements in energy absorption achieved by adding a small amount(0.015 phr)of Multi-Walled Carbon Nanotubes(MWCNTs)to the photocurable resin,thus unlocking new possibilities for the design of innovative lightweight structures with multifunctional attributes. 展开更多
关键词 Sea sponge-inspired lattice structures Additive manufacturing Energy absorption Low-velocity impact Lattice structure NANOCOMPOSITE
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Dual-oxides confined carbonyl iron enabling superior electromagnetic wave absorption and anticorrosion performance
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作者 Weiwei Qi Lan Xiang +9 位作者 Mingqiang Ning Tao Liu Yuanyuan Li Xueheng Zhuang Ganggang Lv Qiang Wu Guoguo Tan Qingzheng Jiang Qikui Man Baogen Shen 《Nano Materials Science》 2026年第2期446-456,共11页
With the increasing requirements of electromagnetic wave(EMW)absorption,developing EMW absorbers with high-efficiency anti-corrosion performance which can be effectively applied in extreme corrosive environments is im... With the increasing requirements of electromagnetic wave(EMW)absorption,developing EMW absorbers with high-efficiency anti-corrosion performance which can be effectively applied in extreme corrosive environments is imperative and constitutes a hot issue in the current research.Herein,based on the composition modulation of ZrO_(2)and SiO_(2)layer,the dual-oxides confined carbonyl iron(CI@ZrO_(2)/SiO_(2))composite displays a minimum reflection loss(RLmin)of-48.58 dB@1.9 mm and an effective absorption bandwidth(EAB)of 7.62 GHz@1.6 mm.Besides,the CI@ZrO_(2)/SiO_(2)displays superior corrosion resistance with corrosion current density(i_(corr))of 8.62×10^(-7)A/cm^(2)and polarization resistance(Rp)of 3.64×10^(5)Ω.This work proposes a strategy to optimize the broadband EMW absorption properties as well as the mass production toward the corrosion resistance applications. 展开更多
关键词 Dual-oxides CI@ZrO_(2)/SiO_(2) Electromagnetic wave absorption ANTI-CORROSION
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Multiscale Design of Dual-Gradient Metamaterials Using Gel-Mediated 3D-Printed Graphene Aerogels for Broadband Electromagnetic Absorption
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作者 Xiong Lv Changfeng Li +4 位作者 Ge Wang Diana Estevez Junjie Yang Qian Chen Faxiang Qin 《Nano-Micro Letters》 2026年第5期522-542,共21页
Three-dimensional(3D)-printedgraphene aerogels hold promise for electromagneticwave absorption(EWA)engineering due to itsultralow density,outstanding electromagnetic dissipationwith the flexibility and precision of ma... Three-dimensional(3D)-printedgraphene aerogels hold promise for electromagneticwave absorption(EWA)engineering due to itsultralow density,outstanding electromagnetic dissipationwith the flexibility and precision of manufacturingstrategies.However,their high conductivitycauses severe impedance mismatch,limiting EWAperformance.3D printing requirements also constrainthe dielectric properties of printable grapheneinks,hindering the integration of high-performanceabsorbers with advanced manufacturing.This studyproposes a polyacrylic acid(PAA)gel-mediated3D porous graphene oxide(GO)aerogel multiscaleregulation strategy.Precise gel content control enablesdual-gradient tuning of the rheology(Benefitingdirect ink writing(DIW))and dielectric loss(Enhancing EWA)of GO/PAA composites and reduces aerogel density(6.9 mg cm^(-3)from28.2 mg cm^(-3)).Thermal reduction decomposes PAA into amorphous carbon nanoparticles anchored on reduced graphene oxide(rGO),enhancingimpedance matching and absorption via synergistic 0D/2D interfacial polarization and conductive loss.The optimized rGO/PAA aerogelachieves a minimum reflection loss(RL)of-39.86 dB at 2.5 mm and an effective absorption bandwidth(EAB)of 8.36 GHz(9.64-18 GHz)at3.2 mm.Combining DIW and this aerogel,we design a metamaterial absorber(MA)with dual material(dielectric loss)and structural gradients.This MA exhibits an ultrawide EAB of 14 GHz(4-18 GHz)with a total thickness of 7.8 mm.This work establishes a coupled design paradigmof“composition-structure-performance,”providing an engineerable solution for developing lightweight,broadband EWA materials. 展开更多
关键词 Electromagnetic wave absorption Gel-mediated porous graphene aerogel Dual-gradient regulation Direct ink writing
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Energy absorption properties and failure modes of flexible UHMWPE foam protective sandwich structure subjected to low-velocity impact
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作者 Xiaoke Liu Kejing Yu Pengwan Chen 《Defence Technology(防务技术)》 2026年第2期32-48,共17页
Flexible materials play a crucial role in protecting against behind armour blunt trauma(BABT).However,their compliance complicates the understanding of failure mechanisms and energy absorption.This study used a combin... Flexible materials play a crucial role in protecting against behind armour blunt trauma(BABT).However,their compliance complicates the understanding of failure mechanisms and energy absorption.This study used a combined experimental and numerical approach to investigate the response and failure modes of a flexible ultra-high-molecular-weight polyethylene(UHMWPE)foam protective sandwich structure(UFPSS)under low-velocity impact(LVI).A finite element(FE)model,accounting for nonlinear large deformation and strain-rate-dependent material behavior,was developed for a woven-UFPSS(featuring a plain-woven fabric structure)subjected to a 50 J impact.Experimental and numerical results showed strong agreement in peak force(error<5%),maximum displacement(error<6%),and buffer time(error<8%).The impact's kinetic energy was mainly converted into internal energy of the fabric and foam materials(~50%),viscous dissipation in the foam core(12%-15%),frictional work at the contact interfaces(5%-6%),and work by the pneumatic fixture clamping force(~38%).This study provides the first investigation of the LVI performance of sandwich structures with all soft material layers,offering significant insights for the application of compliant materials in protective fields. 展开更多
关键词 Sandwich structure Ultra-high-molecular-weight polyethylene(UHMWPE) Low-velocity impact(LVI) Failure mode Energy absorption
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Magnetic-Dielectric Synergy in One-Dimensional Metal Heterostructures for Enhanced Low-Frequency Microwave Absorption
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作者 Feiyue Hu Peigen Zhang +10 位作者 Pei Ding Shuo Zhang Bingbing Fan Ali Saffar Shamshirgar Wei Zheng Wenwen Sun Longzhu Cai Haijiao Xie Qiyue Shao Johanna Rosen ZhengMing Sun 《Nano-Micro Letters》 2026年第5期371-390,共20页
Microwave absorption(MA)materials often face poor synergy between impedance matching and attenuation in the low-frequency range.Balancing permittivity and permeability through magnetic-dielectric synergy is a promisin... Microwave absorption(MA)materials often face poor synergy between impedance matching and attenuation in the low-frequency range.Balancing permittivity and permeability through magnetic-dielectric synergy is a promising strategy to address this issue.To realize the synergy,herein,Sn whiskers with an in situ oxide layer served as substrates for magnetic-loss-active CoNi nanosheet growth,forming a hierarchical CoNi@SnO_(2)@Sn(CNS)heterostructure.The CNS absorber achieves a minimum reflection loss(RL_(min))value of-62.29 dB with an effective absorption bandwidth(EAB)of 2.2 GHz,covering the entire C-band with 70%absorption at only 2.61 mm thickness.The nanosheet design of CoNi enhances magnetic anisotropy to promote natural resonance,while the conductive Sn core and abundant Sn/SnO_(2) and CoNi/SnO_(2) heterointerfaces facilitate conduction loss and dielectric polarization.When composited into a thermoplastic polyurethane(TPU)matrix,the resulting CNS/TPU-2 film(20 wt%CNS)exhibits an RL_(min) value of-61.04 dB and a 2.5 GHz EAB.Its in-plane and through-plane thermal conductivities reach 2.41 and 0.51 W m^(-1) K^(-1),representing 4.1 and 2.6 times those of pure TPU films,respectively,facilitating heat dissipation from protected devices.This work provides valuable insights into magnetic-dielectric synergy for low-frequency MA of 1D metal-based materials,offering promising potential for 5G communications and flexible electronics. 展开更多
关键词 Low frequency microwave absorption Magnetic-dielectric synergy MAX phase CoNi@SnO_(2)@Sn heterostructure Thermal conductivity
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Directional Three‑Dimensional Macroporous Carbon Foams Decorated with WC_(1−x)Nanoparticles Derived from Salting‑Out Protein Assemblies for Highly Effective Electromagnetic Absorption
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作者 Yongzheng Chen Lixue Gai +5 位作者 Bo Hu Yan Wang Yanyi Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 2026年第3期1-21,共21页
Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usu... Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components. 展开更多
关键词 3D macroporous carbon-based foams Directional pore channels Salting-out protein assemblies EM wave absorption Directional dependence
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Facile synthesis of porous Fe_(3)O_(4)/C composites derived from waste residues of soybean and electrolytic manganese for superior electromagnetic wave absorption
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作者 Zihao Liu Kaixiong Xiang +4 位作者 Yujia Nie Yiting Cheng Shaohua Jiang Han Chen Wei Zhou 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期704-715,共12页
With growing concerns regarding electromagnetic pollution,low-cost,environmentally friendly,and high-performance electromagnetic wave absorption(EWA)materials have attracted significant attention.This paper reports on... With growing concerns regarding electromagnetic pollution,low-cost,environmentally friendly,and high-performance electromagnetic wave absorption(EWA)materials have attracted significant attention.This paper reports on the synthesis of porous Fe_(3)O_(4)/C composites that incorporate dielectric and magnetic loss mechanisms via the carbothermal reduction method and optimization of waste ratio to enhance EWA performance.The Fe_(3)O_(4)/C composites with 10wt%soybean residues(Fe_(3)O_(4)/C-10),demonstrated the best EWA performance,achieving the minimum reflection loss of−56.4 dB and a bandwidth of 2.14 GHz at a thickness of 2.23 mm.This enhanced EWA performance is primarily attributable to improved impedance matching and the synergistic effect between dielectric and magnetic losses.Furthermore,radar cross-sectional simulations confirmed the practical feasibility of the porous Fe_(3)O_(4)/C composites.This study proposes a viable strategy for utilizing soybean residue and electrolytic manganese residue,highlighting their potential applications in EWA. 展开更多
关键词 biomass-derived porous carbon electrolytic manganese residue Fe_(3)O_(4) electromagnetic wave absorption
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Gyroid-structured SiOC composite with excellent broadband microwave absorption and load-bearing performance
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作者 Hanjun Wei Siyu Chen +5 位作者 Zhiyong Chen Lu Tang Jimei Xue Cunxian Wang Zhijun Wang Ying Li 《Defence Technology(防务技术)》 2026年第1期277-288,共12页
Designing materials with both structural load-bearing capacity and broadband electromagnetic(EM)wave absorption properties remains a significant challenge.In this work,SiOC/SiC/SiO_(2)composite with gyroid structures ... Designing materials with both structural load-bearing capacity and broadband electromagnetic(EM)wave absorption properties remains a significant challenge.In this work,SiOC/SiC/SiO_(2)composite with gyroid structures were prepared through digital light processing(DLP)3D printing,polymer-derived ceramics(PDCs),chemical vapor infiltration(CVI),and oxidation technologies.The incorporation of the CVISiC phase effectively increases the dissipation capability,while the synergistic interaction between the gyroid structure and SiO_(2)phase significantly improves impedance matching performance.The SiOC/SiC/SiO_(2)composite achieved a minimum reflection loss(RL min)of-62.2 d B at 4.3 mm,and the effective absorption bandwidth(EAB)covered the X-band,with a thickness range of 4.1 mm-4.65 mm.The CST simulation results explain the broadband and low-frequency absorption characteristics,with an EAB of 8.4 GHz(9.6-18 GHz)and an RL min of-21.5 dB at 5 GHz.The excellent EM wave attenuation performance is associated primarily with polarization loss,conduction loss,the gyroid structure's enhancement of multiple reflections and scattering of EM waves,and the resonance effect between the structural units.The SiOC/SiC/SiO_(2)composite also demonstrated strong mechanical properties,with a maximum compressive failure strength of 31.6 MPa in the height direction.This work opens novel prospects for the development of multifunctional structural wave-absorbing materials suitable for broadband microwave absorption and load-bearing properties. 展开更多
关键词 Digital light processing Gyroid structure SiOC/SiC/SiO_(2)composite Microwave absorption Load-bearing properties
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The isolation of prophyra-334 from marine algae and its UV-absorption behavior 被引量:1
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作者 张朝辉 高昕Department of Food Engineering +5 位作者 Ocean University of China Qingdao 266003 China Yuri Tashiro Shingo Matsukawa Hiroo Ogawa 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第4期400-405,共6页
Prophyra-334 was prepared by methanol extraction and HPLC methods from marine algae (dried laver). It is a sunscreen compound that has good absorption of ultraviolet radiations in the wavelength ranges of 200-400 nm... Prophyra-334 was prepared by methanol extraction and HPLC methods from marine algae (dried laver). It is a sunscreen compound that has good absorption of ultraviolet radiations in the wavelength ranges of 200-400 nm. The absorption maximum wavelength of prophyra-334 is at 334 nm, so defined the name. The molar extinction coefficient (ε) of prophyra-334 in aqueous solution at 334 nm wavelength is 4.23×10^4. The absorption of prophyra-334 in organic solvents differs in aqueous solutions. In polar organic solvents, the absorption maximum wavelength of prophyra-334 has a slight shift toward longer wavelength compared with that in pure water. On the contrary, in inert non-polar organic solvents, the absorption maximum wavelength and the shape of absorption spectra of prophyra-334 are changed. The effects of organic solvents on prophyra-334 stability suggested that: (1) the absorbance of prophyra-334 in water is generally constant at temperature of 60℃ in 24 h, meaning that prophyra-334 is quite stable in water; (2) the absorbance of prophyra-334 in ethanol and hexane decreases at the same condition. The stability of prophyra-334 in organic solvents is less than that in aqueous solution. In benzene, the prophyra-334 is very instable. 展开更多
关键词 prophyra-334 EXTRACTION isolation marine algae organic solvent UV-absorption
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Research on the Sound Characteristic in the Active Sound Absorption and Isolation of the Piezoelectric Ceramics
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作者 congyun zhu jigao niu +2 位作者 fujie lu huifu xing guofang ding 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第3期81-88,共8页
The sound characteristic of the piezoelectric ceramics is posed for the excellent mechanic and electric coupling performance of piezoelectric material.Two pieces of piezoelectric ceramic are used as materials of activ... The sound characteristic of the piezoelectric ceramics is posed for the excellent mechanic and electric coupling performance of piezoelectric material.Two pieces of piezoelectric ceramic are used as materials of active absorption and active isolation,two pieces of PVDF with equal distance are placed in the front of the material in order to measure the incidence plane wave and the reflected wave,the voltages are applied on the surface of the material in order to make the reflected wave and transmission wave be zero using the adaptive controlling.At last,emulation is carried out with plane wave,and good absorption and isolation effect is achieved. 展开更多
关键词 ACTIVE absorption ACTIVE isolation PIEZOELECTRIC material
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