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MXene Hollow Spheres Supported by a C–Co Exoskeleton Grow MWCNTs for Efficient Microwave Absorption 被引量:2
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作者 Ze Wu Xiuli Tan +4 位作者 Jianqiao Wang Youqiang Xing Peng Huang Bingjue Li Lei Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期76-94,共19页
High-performance microwave absorption(MA) materials must be studied immediately since electromagnetic pollution has become a problem that cannot be disregarded. A straightforward composite material, comprising hollow ... High-performance microwave absorption(MA) materials must be studied immediately since electromagnetic pollution has become a problem that cannot be disregarded. A straightforward composite material, comprising hollow MXene spheres loaded with C–Co frameworks, was prepared to develop multiwalled carbon nanotubes(MWCNTs). A high impedance and suitable morphology were guaranteed by the C–Co exoskeleton, the attenuation ability was provided by the MWCNTs endoskeleton, and the material performance was greatly enhanced by the layered core–shell structure. When the thickness was only 2.04 mm, the effective absorption bandwidth was 5.67 GHz, and the minimum reflection loss(RLmin) was-70.70 d B. At a thickness of 1.861 mm, the sample calcined at 700 ℃ had a RLmin of-63.25 d B. All samples performed well with a reduced filler ratio of 15 wt%. This paper provides a method for making lightweight core–shell composite MA materials with magnetoelectric synergy. 展开更多
关键词 MXene C-Co skeleton MWCNTS Microwave absorption
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Inherent thermal-responsive strategies for safe lithium batteries 被引量:2
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作者 Jia-Xin Guo Chang Gao +9 位作者 He Liu Feng Jiang Zaichun Liu Tao Wang Yuan Ma Yiren Zhong Jiarui He Zhi Zhu Yuping Wu Xin-Bing Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期519-534,I0012,共17页
Safe batteries are the basis for next-generation application scenarios such as portable energy storage devices and electric vehicles,which are crucial to achieving carbon neutralization.Electrolytes,separators,and ele... Safe batteries are the basis for next-generation application scenarios such as portable energy storage devices and electric vehicles,which are crucial to achieving carbon neutralization.Electrolytes,separators,and electrodes as main components of lithium batteries strongly affect the occurrence of safety accidents.Responsive materials,which can respond to external stimuli or environmental change,have triggered extensive attentions recently,holding great promise in facilitating safe and smart batteries.This review thoroughly discusses recent advances regarding the construction of high-safety lithium batteries based on internal thermal-responsive strategies,together with the corresponding changes in electrochemical performance under external stimulus.Furthermore,the existing challenges and outlook for the design of safe batteries are presented,creating valuable insights and proposing directions for the practical implementation of safe lithium batteries. 展开更多
关键词 Lithium battery Thermal safety Thermal runaway Thermal-responsive
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一种小型化人工表面等离激元传感系统——实现自适应和高灵敏的气体检测 被引量:1
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作者 Xuanru Zhang Jia Wen Zhu Tie Jun Cui 《Engineering》 SCIE EI CAS CSCD 2024年第4期86-94,共9页
Resonantly enhanced dielectric sensing has superior sensitivity and accuracy because the signal is measured from relative resonance shifts that are immune to signal fluctuations.For applications in the Internet of Thi... Resonantly enhanced dielectric sensing has superior sensitivity and accuracy because the signal is measured from relative resonance shifts that are immune to signal fluctuations.For applications in the Internet of Things(IoT),accurate detection of resonance frequency shifts using a compact circuit is in high demand.We proposed an ultracompact integrated sensing system that merges a spoof surface plasmon resonance sensor with signal detection,processing,and wireless communication.A softwaredefined scheme was developed to track the resonance shift,which minimized the hardware circuit and made the detection adaptive to the target resonance.A microwave spoof surface plasmon resonator was designed to enhance sensitivity and resonance intensity.The integrated sensing system was constructed on a printed circuit board with dimensions of 1.8 cm×1.2 cm and connected to a smartphone wirelessly through Bluetooth,working in both frequency scanning mode and resonance tracking mode and achieving a signal-to-noise ratio of 69 dB in acetone vapor sensing.This study provides an ultracompact,accurate,adaptive,sensitive,and wireless solution for resonant sensors in the IoT. 展开更多
关键词 Spoof surface plasmons Internet of Things Integrated sensing Resonance tracking Microwave sensing
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NLRP3-mediated autophagy dysfunction links gut microbiota dysbiosis to tau pathology in chronic sleep deprivation 被引量:1
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作者 Na Zhao Xiu Chen +6 位作者 Qiu-Gu Chen Xue-Ting Liu Fan Geng Meng-Meng Zhu Fu-Ling Yan Zhi-Jun Zhang Qing-Guo Ren 《Zoological Research》 SCIE CSCD 2024年第4期857-874,共18页
Emerging evidence indicates that sleep deprivation(SD)can lead to Alzheimer’s disease(AD)-related pathological changes and cognitive decline.However,the underlying mechanisms remain obscure.In the present study,we id... Emerging evidence indicates that sleep deprivation(SD)can lead to Alzheimer’s disease(AD)-related pathological changes and cognitive decline.However,the underlying mechanisms remain obscure.In the present study,we identified the existence of a microbiota-gut-brain axis in cognitive deficits resulting from chronic SD and revealed a potential pathway by which gut microbiota affects cognitive functioning in chronic SD.Our findings demonstrated that chronic SD in mice not only led to cognitive decline but also induced gut microbiota dysbiosis,elevated NLRP3 inflammasome expression,GSK-3βactivation,autophagy dysfunction,and tau hyperphosphorylation in the hippocampus.Colonization with the“SD microbiota”replicated the pathological and behavioral abnormalities observed in chronic sleep-deprived mice.Remarkably,both the deletion of NLRP3 in NLRP3-/-mice and specific knockdown of NLRP3 in the hippocampus restored autophagic flux,suppressed tau hyperphosphorylation,and ameliorated cognitive deficits induced by chronic SD,while GSK-3βactivity was not regulated by the NLRP3 inflammasome in chronic SD.Notably,deletion of NLRP3 reversed NLRP3 inflammasome activation,autophagy deficits,and tau hyperphosphorylation induced by GSK-3βactivation in primary hippocampal neurons,suggesting that GSK-3β,as a regulator of NLRP3-mediated autophagy dysfunction,plays a significant role in promoting tau hyperphosphorylation.Thus,gut microbiota dysbiosis was identified as a contributor to chronic SD-induced tau pathology via NLRP3-mediated autophagy dysfunction,ultimately leading to cognitive deficits.Overall,these findings highlight GSK-3βas a regulator of NLRP3-mediated autophagy dysfunction,playing a critical role in promoting tau hyperphosphorylation. 展开更多
关键词 Chronic sleep deprivation Tau pathology NLRP3 inflammasome AUTOPHAGY GSK-3β Microbiota-gut-brain axis
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Photocatalytic activation of sulfite by N-doped porous biochar/MnFe_(2)O_(4) interface-driven catalyst for efficient degradation of tetracycline 被引量:1
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作者 Long Cheng Yuanhui Ji 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期481-494,共14页
A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline... A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous structure.The adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic performance.Moreover,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical calculation.Considering the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar. 展开更多
关键词 BIOCHAR MnFe_(2)O_(4) SULFITE Adsorption PHOTOCATALYSIS
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Medin synergized with vascular amyloid-beta deposits accelerates cognitive decline in Alzheimer's disease:a potential biomarker 被引量:1
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作者 Xiao Ge Li Li Chunming Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1414-1414,共1页
Brain vascular dysfunction in Alzheimer s disease(AD) pathogenesis has become increasingly clea r.Accumulating evidence shows that damaged vascular,including large or small vessels and even neurovascular unit,may acce... Brain vascular dysfunction in Alzheimer s disease(AD) pathogenesis has become increasingly clea r.Accumulating evidence shows that damaged vascular,including large or small vessels and even neurovascular unit,may accelerate the neuropathological process of AD via disrupting brain hypoperfusion,aberrant angiogenesis,and neuroinflammatory response,etc.Thus,vascular dysfunction makes a substantially contribution to the cognitive decline of AD patients. 展开更多
关键词 ALZHEIMER AMYLOID PERFUSION
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An MPI parallel DEM-IMB-LBM framework for simulating fluid-solid interaction problems 被引量:2
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作者 Ming Xia Liuhong Deng +3 位作者 Fengqiang Gong Tongming Qu Y.T.Feng Jin Yu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2219-2231,共13页
The high-resolution DEM-IMB-LBM model can accurately describe pore-scale fluid-solid interactions,but its potential for use in geotechnical engineering analysis has not been fully unleashed due to its prohibitive comp... The high-resolution DEM-IMB-LBM model can accurately describe pore-scale fluid-solid interactions,but its potential for use in geotechnical engineering analysis has not been fully unleashed due to its prohibitive computational costs.To overcome this limitation,a message passing interface(MPI)parallel DEM-IMB-LBM framework is proposed aimed at enhancing computation efficiency.This framework utilises a static domain decomposition scheme,with the entire computation domain being decomposed into multiple subdomains according to predefined processors.A detailed parallel strategy is employed for both contact detection and hydrodynamic force calculation.In particular,a particle ID re-numbering scheme is proposed to handle particle transitions across sub-domain interfaces.Two benchmarks are conducted to validate the accuracy and overall performance of the proposed framework.Subsequently,the framework is applied to simulate scenarios involving multi-particle sedimentation and submarine landslides.The numerical examples effectively demonstrate the robustness and applicability of the MPI parallel DEM-IMB-LBM framework. 展开更多
关键词 Discrete element method(DEM) Lattice Boltzmann method(LBM) Immersed moving boundary(IMB) Multi-cores parallelization Message passing interface(MPI) CPU Submarine landslides
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Potential clinical application of microRNAs in bladder cancer 被引量:1
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作者 Pei Wang Xiaowei Wei +1 位作者 Xiaojun Qu Yefei Zhu 《Journal of Biomedical Research》 CAS CSCD 2024年第4期289-306,共18页
Bladder cancer(BC)is the tenth most prevalent malignancy globally,presenting significant clinical and societal challenges because of its high incidence,rapid progression,and frequent recurrence.Presently,cystoscopy an... Bladder cancer(BC)is the tenth most prevalent malignancy globally,presenting significant clinical and societal challenges because of its high incidence,rapid progression,and frequent recurrence.Presently,cystoscopy and urine cytology serve as the established diagnostic methods for BC.However,their efficacy is limited by their invasive nature and low sensitivity.Therefore,the development of highly specific biomarkers and effective noninvasive detection strategies is imperative for achieving a precise and timely diagnosis of BC,as well as for facilitating an optimal tumor treatment and an improved prognosis.microRNAs(miRNAs),short noncoding RNA molecules spanning around 20–25 nucleotides,are implicated in the regulation of diverse carcinogenic pathways.Substantially altered miRNAs form robust functional regulatory networks that exert a notable influence on the tumorigenesis and progression of BC.Investigations into aberrant miRNAs derived from blood,urine,or extracellular vesicles indicate their potential roles as diagnostic biomarkers and prognostic indicators in BC,enabling miRNAs to monitor the progression and predict the recurrence of the disease.Simultaneously,the investigation centered on miRNA as a potential therapeutic agent presents a novel approach for the treatment of BC.This review comprehensively analyzes biological roles of miRNAs in tumorigenesis and progression,and systematically summarizes their potential as diagnostic and prognostic biomarkers,as well as therapeutic targets for BC.Additionally,we evaluate the progress made in laboratory techniques within this field and discuss the prospects. 展开更多
关键词 bladder cancer MICRORNAS BIOMARKER DIAGNOSIS detection method
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Deep learning for joint channel estimation and feedback in massive MIMO systems 被引量:1
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作者 Jiajia Guo Tong Chen +3 位作者 Shi Jin Geoffrey Ye Li Xin Wang Xiaolin Hou 《Digital Communications and Networks》 SCIE CSCD 2024年第1期83-93,共11页
The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base stations.However,th... The great potentials of massive Multiple-Input Multiple-Output(MIMO)in Frequency Division Duplex(FDD)mode can be fully exploited when the downlink Channel State Information(CSI)is available at base stations.However,the accurate CsI is difficult to obtain due to the large amount of feedback overhead caused by massive antennas.In this paper,we propose a deep learning based joint channel estimation and feedback framework,which comprehensively realizes the estimation,compression,and reconstruction of downlink channels in FDD massive MIMO systems.Two networks are constructed to perform estimation and feedback explicitly and implicitly.The explicit network adopts a multi-Signal-to-Noise-Ratios(SNRs)technique to obtain a single trained channel estimation subnet that works well with different SNRs and employs a deep residual network to reconstruct the channels,while the implicit network directly compresses pilots and sends them back to reduce network parameters.Quantization module is also designed to generate data-bearing bitstreams.Simulation results show that the two proposed networks exhibit excellent performance of reconstruction and are robust to different environments and quantization errors. 展开更多
关键词 Channel estimation CSI feedback Deep learning Massive MIMO FDD
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Amitriptyline inhibits NLRP3 inflammasome activation via the ASM/CE pathway in a cell model of NAFLD 被引量:1
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作者 QIN LIU CHUNYAN NIU +3 位作者 QIANG ZHANG SHIQIN SUN YUE CHEN YONGQIANG SHI 《BIOCELL》 SCIE 2024年第5期759-769,共11页
Background:Nonalcoholic fatty liver disease(NAFLD)is a global health concern with the acid sphingomyelinase(ASM)/ceramide(CE)pathway and the NOD-like receptor family,pyrin domain-containing protein 3(NLRP3)inflammasom... Background:Nonalcoholic fatty liver disease(NAFLD)is a global health concern with the acid sphingomyelinase(ASM)/ceramide(CE)pathway and the NOD-like receptor family,pyrin domain-containing protein 3(NLRP3)inflammasome identified as pivotal players in lipid disorders and inflammation.This study explores the interaction mechanism between the ASM/CE pathway and NLRP3 in NAFLD cell models,aiming to understand the impact of amitriptyline(Ami),an ASM inhibitor,on lipid deposition and hepatocyte injury by regulating the ASM/CE-NLRP3 pathway.Methods:HepG2 and HL-7702 cells were exposed to free fatty acids(FFAs)to establish the NAFLD model.The cells were divided into 5 groups:control group,model group,Ami group,tumor necrosis factoralpha(TNF-α)group,and Ami+TNF-αgroup.Intracellular lipid droplets were visualized using Oil Red O staining,and Western blot analysis quantified ASM,NLRP3,and caspase 1 protein expression.Enzyme linked immunosorbent assay(ELISA)was measured CE and ASM levels,while qRT-PCR assessed mRNA expression.The apoptotic rate was evaluated by flow cytometry(FCM).Results:Following FFAs incubation,significant increases in ASM and CE levels were observed in HepG2 and HL-7702 cells,accompanied by elevated expression of NLRP3,and caspase 1,and IL-1β.TNF-αtreatment further amplified these indicators.Ami demonstrated a reduction in lipid deposition,suppressed ASM/CE pathway activation,downregulated NLRP3 and caspase 1 expression,and improved apoptosis.Additionally,MCC950,a selective inhibitor of the NLRP3,mitigated NLRP3,caspase 1,and IL-1βexpression,alleviating lipid deposition and apoptosis in the NAFLD cell model.Conclusion:The ASM/CE-NLRP3 pathway in NAFLD cells promotes hepatocyte steatosis,inflammation,and cell damage.Ami emerges as a promising therapeutic agent by inhibiting the ASM/CE-NLRP3 pathway,underscoring its potential as a key target for NAFLD treatment. 展开更多
关键词 Nonalcoholic fatty liver disease HEPATOCYTE AMITRIPTYLINE ASM/CE pathway NLRP3 Nonalcoholic steatohepatitis
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A particle-resolved heat-particle-fluid coupling model by DEM-IMB-LBM 被引量:1
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作者 Ming Xia Jinlong Fu +2 位作者 Y.T.Feng Fengqiang Gong Jin Yu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2267-2281,共15页
Multifield coupling is frequently encountered and also an active area of research in geotechnical engineering.In this work,a particle-resolved direct numerical simulation(PR-DNS)technique is extended to simulate parti... Multifield coupling is frequently encountered and also an active area of research in geotechnical engineering.In this work,a particle-resolved direct numerical simulation(PR-DNS)technique is extended to simulate particle-fluid interaction problems involving heat transfer at the grain level.In this extended technique,an immersed moving boundary(IMB)scheme is used to couple the discrete element method(DEM)and lattice Boltzmann method(LBM),while a recently proposed Dirichlet-type thermal boundary condition is also adapted to account for heat transfer between fluid phase and solid particles.The resulting DEM-IBM-LBM model is robust to simulate moving curved boundaries with constant temperature in thermal flows.To facilitate the understanding and implementation of this coupled model for non-isothermal problems,a complete list is given for the conversion of relevant physical variables to lattice units.Then,benchmark tests,including a single-particle sedimentation and a two-particle drafting-kissing-tumbling(DKT)simulation with heat transfer,are carried out to validate the accuracy of our coupled technique.To further investigate the role of heat transfer in particle-laden flows,two multiple-particle problems with heat transfer are performed.Numerical examples demonstrate that the proposed coupling model is a promising high-resolution approach for simulating the heat-particle-fluid coupling at the grain level. 展开更多
关键词 Particle-fluid interaction Heat transfer Discrete element method(DEM) Lattice Boltzmann method(LBM) Dirichlet-type thermal boundary Direct numerical simulation
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Ruxolitinib improves the inflammatory microenvironment,restores glutamate homeostasis,and promotes functional recovery after spinal cord injury 被引量:1
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作者 Jiang Cao Xiao Yu +10 位作者 Jingcheng Liu Jiaju Fu Binyu Wang Chaoqin Wu Sheng Zhang Hongtao Chen Zi Wang Yinyang Xu Tao Sui Jie Chang Xiaojian Cao 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2499-2512,共14页
The inflammatory microenvironment and neurotoxicity can hinder neuronal regeneration and functional recovery after spinal cord injury.Ruxolitinib,a JAK-STAT inhibitor,exhibits effectiveness in autoimmune diseases,arth... The inflammatory microenvironment and neurotoxicity can hinder neuronal regeneration and functional recovery after spinal cord injury.Ruxolitinib,a JAK-STAT inhibitor,exhibits effectiveness in autoimmune diseases,arthritis,and managing inflammatory cytokine storms.Although studies have shown the neuroprotective potential of ruxolitinib in neurological trauma,the exact mechanism by which it enhances functional recovery after spinal cord injury,particularly its effect on astrocytes,remains unclear.To address this gap,we established a mouse model of T10 spinal cord contusion and found that ruxolitinib effectively improved hindlimb motor function and reduced the area of spinal cord injury.Transcriptome sequencing analysis showed that ruxolitinib alleviated inflammation and immune response after spinal cord injury,restored EAAT2 expression,reduced glutamate levels,and alleviated excitatory toxicity.Furthermore,ruxolitinib inhibited the phosphorylation of JAK2 and STAT3 in the injured spinal cord and decreased the phosphorylation level of nuclear factor kappa-B and the expression of inflammatory factors interleukin-1β,interleukin-6,and tumor necrosis factor-α.Additionally,in glutamate-induced excitotoxicity astrocytes,ruxolitinib restored EAAT2 expression and increased glutamate uptake by inhibiting the activation of STAT3,thereby reducing glutamate-induced neurotoxicity,calcium influx,oxidative stress,and cell apoptosis,and increasing the complexity of dendritic branching.Collectively,these results indicate that ruxolitinib restores glutamate homeostasis by rescuing the expression of EAAT2 in astrocytes,reduces neurotoxicity,and effectively alleviates inflammatory and immune responses after spinal cord injury,thereby promoting functional recovery after spinal cord injury. 展开更多
关键词 astrocytes EAAT2 EXCITOTOXICITY glutamate homeostasis JAK-STAT pathway locomotor function NEUROTOXICITY RUXOLITINIB spinal cord injury transcriptome analysis
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Utilization of Basalt Saw Mud as a Spherical Porous Functional Aggregate for the Preparation of Ordinary Structure Concrete 被引量:1
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作者 周永祥 关青锋 +2 位作者 LENG Faguang WANG Jing LI Tianjun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期364-375,共12页
To promote the production and application of artificial aggregates,save natural sand resources and protect the ecological environment,we evaluated the feasibility of using spherical porous functional aggregates(SPFAs)... To promote the production and application of artificial aggregates,save natural sand resources and protect the ecological environment,we evaluated the feasibility of using spherical porous functional aggregates(SPFAs) formed by basalt saw mud under autoclave curing in ordinary structural concrete.In our work,two types of prewetted functional aggregates were taken as replacements for natural aggregates with different volume substitution rates(0%,5%,10%,15%,20%,25%,and 30%) in the preparation of ordinary structural concrete with water-to-binder ratios(W/B) of 0.48 and 0.33.The effects of the functional aggregate properties and content,W/B,and curing age on the fluidity,density,mechanical properties and autogenous shrinkage of ordinary concrete were analyzed.The experimental results showed that the density of concrete declined at a rate of not more than 5%,and the 28 d compressive strength could reach 31.0-68.2 MPa.Low W/B,long curing age and high-quality functional aggregates were conducive to enhancing the mechanical properties of SPFAs concrete.Through the rolling effects,SPFAs can optimize the particle gradation of aggregate systems and improve the fluidity of concrete,and the water stored inside SPFAs provides an internal curing effect,which prolongs the cement hydration process and considerably reduces the autogenous shrinkage of concrete.SPFAs exhibits high strength and high density,as well as being more cost-effective and ecological,and is expected to be widely employed in ordinary structural concrete. 展开更多
关键词 lightweight concrete civil concrete building basalt saw mud fly ash internal curing environmentally friendly
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Fixed-Time Gradient Flows for Solving Constrained Optimization: A Unified Approach
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作者 Xinli Shi Xiangping Xu +1 位作者 Guanghui Wen Jinde Cao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1849-1864,共16页
The accelerated method in solving optimization problems has always been an absorbing topic.Based on the fixedtime(FxT)stability of nonlinear dynamical systems,we provide a unified approach for designing FxT gradient f... The accelerated method in solving optimization problems has always been an absorbing topic.Based on the fixedtime(FxT)stability of nonlinear dynamical systems,we provide a unified approach for designing FxT gradient flows(FxTGFs).First,a general class of nonlinear functions in designing FxTGFs is provided.A unified method for designing first-order FxTGFs is shown under Polyak-Łjasiewicz inequality assumption,a weaker condition than strong convexity.When there exist both bounded and vanishing disturbances in the gradient flow,a specific class of nonsmooth robust FxTGFs with disturbance rejection is presented.Under the strict convexity assumption,Newton-based FxTGFs is given and further extended to solve time-varying optimization.Besides,the proposed FxTGFs are further used for solving equation-constrained optimization.Moreover,an FxT proximal gradient flow with a wide range of parameters is provided for solving nonsmooth composite optimization.To show the effectiveness of various FxTGFs,the static regret analyses for several typical FxTGFs are also provided in detail.Finally,the proposed FxTGFs are applied to solve two network problems,i.e.,the network consensus problem and solving a system linear equations,respectively,from the perspective of optimization.Particularly,by choosing component-wisely sign-preserving functions,these problems can be solved in a distributed way,which extends the existing results.The accelerated convergence and robustness of the proposed FxTGFs are validated in several numerical examples stemming from practical applications. 展开更多
关键词 CONSENSUS constrained optimization disturbance rejection linear equations fixed-time gradient flow(FxTGF).
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Regional Multi-Agent Cooperative Reinforcement Learning for City-Level Traffic Grid Signal Control
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作者 Yisha Li Ya Zhang +1 位作者 Xinde Li Changyin Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第9期1987-1998,共12页
This article studies the effective traffic signal control problem of multiple intersections in a city-level traffic system.A novel regional multi-agent cooperative reinforcement learning algorithm called RegionSTLight... This article studies the effective traffic signal control problem of multiple intersections in a city-level traffic system.A novel regional multi-agent cooperative reinforcement learning algorithm called RegionSTLight is proposed to improve the traffic efficiency.Firstly a regional multi-agent Q-learning framework is proposed,which can equivalently decompose the global Q value of the traffic system into the local values of several regions Based on the framework and the idea of human-machine cooperation,a dynamic zoning method is designed to divide the traffic network into several strong-coupled regions according to realtime traffic flow densities.In order to achieve better cooperation inside each region,a lightweight spatio-temporal fusion feature extraction network is designed.The experiments in synthetic real-world and city-level scenarios show that the proposed RegionS TLight converges more quickly,is more stable,and obtains better asymptotic performance compared to state-of-theart models. 展开更多
关键词 Human-machine cooperation mixed domain attention mechanism multi-agent reinforcement learning spatio-temporal feature traffic signal control
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Valley-dependent transport in a mescoscopic twisted bilayer graphene device
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作者 史文萱 刘翰林 汪军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期61-65,共5页
We study the valley-dependent electron transport in a four-terminal mesoscopic device of the two monolayer graphene nanoribbons vertically stacked together, where the intersection forms a bilayer graphene lattice with... We study the valley-dependent electron transport in a four-terminal mesoscopic device of the two monolayer graphene nanoribbons vertically stacked together, where the intersection forms a bilayer graphene lattice with a controllable twist angle. Using a tight-binding lattice model, we show that the longitudinal and transverse conductances exhibit significant valley polarization in the low energy regime for small twist angles. As the twist angle increases, the valley polarization shifts to the high energy regime. This arises from the regrouping effect of the electron band in the twisted bilayer graphene region. But for relatively large twist angles, no significant valley polarization is observed. These results are consistent with the spectral densities of the twisted bilayer graphene. 展开更多
关键词 twisted bilayer graphene valley-dependent transport graphene nanoribbon CONDUCTANCE
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Design and pricing of maintenance service contract based on Nash non-cooperative game approach
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作者 SU Chun HUANG Kui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期118-129,共12页
Nowadays manufacturers are facing fierce challenge.Apart from the products,providing customers with multiple maintenance options in the service contract becomes more popular,since it can help to improve customer satis... Nowadays manufacturers are facing fierce challenge.Apart from the products,providing customers with multiple maintenance options in the service contract becomes more popular,since it can help to improve customer satisfaction,and ultimately promote sales and maximize profit for the manufacturer.By considering the combinations of corrective maintenance and preventive maintenance,totally three types of maintenance service contracts are designed.Moreover,attractive incentive and penalty mechanisms are adopted in the contracts.On this basis,Nash non-cooperative game is applied to analyze the revenue for both the manufacturer and customers,and so as to optimize the pricing mechanism of maintenance service contract and achieve a win-win situation.Numerical experiments are conducted.The results show that by taking into account the incentive and penalty mechanisms,the revenue can be improved for both the customers and manufacturer.Moreover,with the increase of repair rate and improvement factor in the preventive maintenance,the revenue will increase gradually for both the parties. 展开更多
关键词 maintenance service contract Nash game incentive and penalty mechanism corrective maintenance preventive maintenance
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Rockburst criterion and evaluation method for potential rockburst pit depth considering excavation damage effect
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作者 Jinhao Dai Fengqiang Gong Lei Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1649-1666,共18页
Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Ta... Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Taking two diversion tunnels of Jinping II hydropower station for example,the relationship between rockburst pit depth and excavation damage effect is first surveyed.The results indicate that the rockburst pit depth in tunnels with severe damage to rock masses is relatively large.Subsequently,the excavation-induced damage effect is characterized by disturbance factor D based on the Hoek-Brown criterion and wave velocity method.It is found that the EDZ could be further divided into a high-damage zone(HDZ)with D=1 and weak-damage zone(WDZ),and D decays from one to zero linearly.For this,a quantitative evaluation method for potential rockburst pit depth is established by presenting a three-element rockburst criterion considering rock strength,geostress and disturbance factor.The evaluation results obtained by this method match well with actual observations.In addition,the weakening of rock mass strength promotes the formation and expansion of potential rockburst pits.The potential rockburst pit depth is positively correlated with HDZ and WDZ depths,and the HDZ depth has a significant contribution to the potential rockburst pit depth. 展开更多
关键词 Deep tunnel ROCKBURST Rockburst pit Excavation damage effect Hoek-Brown criterion
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Delivering Microrobots in the Musculoskeletal System
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作者 Mumin Cao Renwang Sheng +10 位作者 Yimin Sun Ying Cao Hao Wang Ming Zhang Yunmeng Pu Yucheng Gao Yuanwei Zhang Panpan Lu Gaojun Teng Qianqian Wang Yunfeng Rui 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期585-617,共33页
Disorders of the musculoskeletal system are the major contributors to the global burden of disease and current treatments show limited efficacy.Patients often suffer chronic pain and might eventually have to undergo e... Disorders of the musculoskeletal system are the major contributors to the global burden of disease and current treatments show limited efficacy.Patients often suffer chronic pain and might eventually have to undergo end-stage surgery.Therefore,future treatments should focus on early detection and intervention of regional lesions.Microrobots have been gradually used in organisms due to their advantages of intelligent,precise and minimally invasive targeted delivery.Through the combination of control and imaging systems,microrobots with good biosafety can be delivered to the desired area for treatment.In the musculoskeletal system,microrobots are mainly utilized to transport stem cells/drugs or to remove hazardous substances from the body.Compared to traditional biomaterial and tissue engineering strategies,active motion improves the efficiency and penetration of local targeting of cells/drugs.This review discusses the frontier applications of microrobotic systems in different tissues of the musculoskeletal system.We summarize the challenges and barriers that hinder clinical translation by evaluating the characteristics of different microrobots and finally point out the future direction of microrobots in the musculoskeletal system. 展开更多
关键词 MICROROBOT Musculoskeletal system Targeted delivery Microrobotic systems Magnetic actuation
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A Quick Calculation Method for Radiation Pattern of Submillimeter Telescope with Deformation and Displacement
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作者 Jia You Yi-Wei Yao Zheng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期249-265,共17页
Radiation pattern captures the electromagnetic performance of reflector antennas,which is significantly affected by the deformation of the primary reflector due to gravity and the displacement of the secondary reflect... Radiation pattern captures the electromagnetic performance of reflector antennas,which is significantly affected by the deformation of the primary reflector due to gravity and the displacement of the secondary reflector.During the design process of large reflector antennas,a substantial amount of time is often dedicated to iteratively adjusting structural parameters and validating electromagnetic performance.To improve the efficiency of the design process,we first propose an approximate calculation method of optical path difference(OPD)for the deformation of the primary reflector under gravity and the displacement of the secondary reflector.Then an OPD fitting function based on the modified Zernike polynomials is proposed to capture the phase difference of radiation over the aperture plane,based on which the radiation pattern will be obtained quickly by the aperture field integration method.Numerical experiments demonstrate the effectiveness of the proposed quick calculation method for analyzing the radiation pattern of a 10.4 m submillimeter telescope antenna at its highest operating frequency of 856 GHz.In comparison with the numerical simulation method based on GRASP(which is an antenna electromagnetic analysis tool combining physical optics(PO)and physical theory of diffraction(PTD)),the quick calculation method reduces the time for radiation pattern analysis from more than one hour to less than two minutes.Furthermore,the quick calculation method exhibits excellent accuracy for the figure of merit(FOM)of the radiation pattern.Therefore,the proposed quick calculation method can obtain the radiation pattern with high speed and accuracy.Compared to the time-consuming numerical simulation method(PO and PTD),it can be employed for quick analysis of the radiation pattern for the lateral displacement of the secondary reflector and the deformation of the primary reflector under gravity in the design process of a reflector antenna. 展开更多
关键词 INSTRUMENTATION high angular resolution-methods data analysis-methods ANALYTICAL
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