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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 912-920页

作者：张超任秀华 ba Dongzhe ZHANG Jianhua Li Jianyong GUO Mengnan GAO Yinghao WANG Guixin Li Jiayang School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan 250101China Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of Education of ChinaSchool of Mechanical EngineeringShandong UniversityJinan 250061China

Because inferior mechanical strength of granite polymer composite(GPC)has become the main drawback limiting its application and popularization,Mo fibers were added into(GPC)to improve its mechanical *** properties of matrix materials with different mass ratio of resin and stabilizer(MRRS)were investigated *** influences of MRRS on interface bonding strength of Mo fiber-matrix,wettability and mechanical strength of GPC were discussed,respectively,and the theoretical calculation result of MRRS k was obtained,with the optimal value of k=*** k=4,tensile strength,tensile strain and fracture stress of the cured resin achieve the maximum *** for k=7,the corresponding values reach the *** the increase of MRRS k,surface free energy of the cured resin first increases and then decreases,while contact angles between Mo sample and matrix have displayed the opposite *** of resin to Mo fiber is the best at k=*** load of Mo fiber and interface bonding strength appear the maximum at k=4,followed by k=5,k=3 the third,and k=7 the *** k=4,mechanical properties of Mo fiber-reinforced GPC are optimal,which is consistent with the result of theoretical *** study is of great significance to get better component formulas of Mo fiber reinforced GPC and to improve its application in machine tools.

关键词： polymer composite fiber mechanical strength interface bonding

Molecular and cellular mechanisms of neuroprotection by oligopeptides from snake venoms

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BiOCELL 2024年第6期48卷 897-904页

作者： CARLOS ALBERTO-SiLVA BRENda RUFiNO da SiLVA Natural and Humanities Sciences Center Experimental Morphophysiology LaboratoryFederal University of ABC(UFABC)São Bernardo do CampoSão PauloBrazil

Venom snake-derived peptides have multiple biochemical,pharmacological,and toxicological proﬁles,allowing for the discovery of new medicinal products and therapeutic *** review speciﬁcally examines the fundamental elements of neuroprotection offered by different oligopeptides derived from snake *** also includes a brief evaluation of short peptides that are being considered as potential therapeutic ***-rich peptides and tryptophyllin family peptides isolated from the crude venom of Viperidae family snakes,speciﬁcally Bothrops atrox,Bothrops jararaca,and Bothrops moojeni,have been shown to have pro-survival properties,the ability to reduce oxidative stress,and the ability to promote cell viability and mitochondrial *** signiﬁcant mechanisms are related to the neuroprotection mediated by snake venom oligopeptides:(1)Activation of the L-arginine metabolite pathway,such as polyamines from ornithine metabolism,which reduces N-methyl-D-aspartate(NMda)-type glutamate receptor activity;(2)Enhancement of cell viability by activating the nerve growth factor-signaling pathway;and(3)Activation of the Muscarinic acetylcholine receptor subtype M1(mAChR-M1).These small peptides show promise as neuroprotective agents against a variety of neurodegenerative disorders.

关键词： Neuroprotective peptides Neurodegenerative disease Oxidative stress Reactive oxygen species Biopeptides

Robust Space-Time Adaptive Track-Before-Detect Algorithm based on Persymmetry and Symmetric Spectrum

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Journal of Beijing institute of Technology 2024年第1期33卷 65-74页

作者： Xiaojing Su da Xu Dongsheng Zhu Zhixun Ma institute of Acoustics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,can effectively detect low-speed weak ***,due to the complexity and variability of the underwater environment,it is difficult to obtain sufficient secondary data,resulting in a serious decline in the detection and tracking performance,and leading to poor robustness of the *** this paper,based on the adaptive matched filter(AMF)test and the RAO test,underwater monopulse AMF-DP-TBD algorithm and RAO-DP-TBD algorithm which incorporate persymmetry and symmetric spectrum,denoted as PSAMF-DP-TBD and PS-RAO-DP-TBD,are proposed and compared with the AMF-DP-TBD algorithm and RAO-DP-TBD algorithm based on persymmetry array,denoted as P-AMF-DP-TBD and *** simulation results show that the four methods can work normally with sufficient secondary data and slightly insufficient secondary data,but when the secondary data is severely insufficient,the P-AMF-DP-TBD and P-RAO-DP-TBD algorithms has failed while the PSAMF-DP-TBD and PS-RAO-DP-TBD algorithms still have good detection and tracking capabilities.

关键词： space-time adaptive detection track before detect robustness persymmetric property symmetric spectrum AMF test RAO test

Variations and future projections of glacial discharge of Urumqi River Headwaters,eastern Tien Shan(1980s-2017)

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Advances in Climate Change Research 2024年第3期15卷 537-546页

作者： Hui ZHANG Fei-Teng WANG Ping ZHOU Yi-da XiE State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

To address data scarcity on long-term glacial discharge and inadequacies in simulating and predicting hydrological processes in the Tien Shan,this study analysed the observed discharge at multiple timescales over 1980se2017 and projected changes within a representative glacierized high-mountain region:eastern Tien Shan,Central *** processes were simulated to predict changes under four future scenarios(SSP1,SSP2,SSP3,and SSP5)using a classical hydrological model coupled with a glacier dynamics *** rates at annual,monthly(June,July,August)and daily timescales were obtained from two hydrological gauges:Urumqi Glacier No.1 hydrological station(UGH)and Zongkong station(ZK).Overall,annual and summer discharge increased significantly(pions over the study *** intra-annual variations mainly resulted from differences in their recharge *** simulations show that a tipping point in annual discharge at UGH may occur between 2018 and 2024 under the four SSPs *** discharge is predicted to cease earlier at ZK than at *** relates to glacier type and size,suggesting basins with heavily developed small glaciers will reach peak discharge sooner,resulting in an earlier freshwater supply *** findings serve as a reference for research into glacial runoff in Central Asia and provide a decision-making basis for planning local water-resource projects.

关键词： Observed glacial discharge Temporal variations Urumqi River Headwaters Eastern Tien Shan Simulation and projection

Experimental study on seismic reinforcement of bridge foundation on silty clay landslide with inclined interlayer

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 193-207页

作者： Lei da Xiao Hanmo Ran Jianhua Luo Bin Jiang Guanlu Xue Tianlang College of Civil Engineering Sichuan Agricultural UniversityDujiangyan 611830China Sichuan Higher Education Engineering Research Center for Disaster Prevention and Mitigation of Village Construction Dujiangyan 611830China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China

A shaking table test for a bridge foundation reinforced by anti-slide piles on a silty clay landslide model with an inclined interlayer was *** deformation characteristics of the bridge foundation piles and anti-slide piles were analyzed in different loading *** dynamic response law of a silty clay landslide with an inclined interlayer was *** spacing between the rear anti-slide piles and bridge foundation should be reasonably controlled according to the seismic fortification requirements,to avoid the two peaks in the forced deformation of the bridge foundation ***“blocking effect”of the bridge foundation piles reduced the deformation of the forward anti-slide *** stress-strain response of silty clay was intensified as the vibration wave field appeared on the *** the vibration intensified,the thrust distribution of the landslide underwent a process of shifting from triangle to inverted trapezoid,the difference in the acceleration response between the bearing platform and silty clay landslide tended to decrease,and the spectrum amplitude near the natural vibration frequency *** rear anti-slide piles were able to slow down the shear deformation of the soil in front of the piles and avoid excessive acceleration response of the bridge foundation piles.

关键词： silty clay landslide inclined interlayer shaking table test anti-slide pile bridge foundation pile

Restraint effect of partition wall on the tunnel floor heave in layered rock mass

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Journal of Mountain Science 2024年第7期21卷 2462-2479页

作者： YANG Yunyun HUANG da ZHONG Zhu LiU Yang PENG Jianbing School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China.

The presence of horizontal layered rocks in tunnel engineering significantly impacts the stability and strength of the surrounding rock mass,leading to floor heave in the *** study focused on preparing layered specimens of rock-like material with varying thickness to investigate the failure behaviors of tunnel *** results indicate that thin-layered rock mass exhibits weak interlayer bonding,causing rock layers near the surface to buckle and break upwards when subjected to horizontal *** an increase in the layer thickness,a transition in failure mode occurs from upward buckling to shear failure along the plane,leading to a noticeable reduction in floor heave *** primary cause of significant deformation in floor heave is upward buckling *** address this issue,the study proposes the installation of a partition wall in the middle of the floor to mitigate heave deformation of the rock *** results demonstrate that the partition wall has a considerable stabilizing effect on the floor,reducing the zone of buckling failure and minimizing floor heave *** is crucial for the partition wall to be sufficiently high to prevent buckling failure and ensure *** simulation calculations on an engineering example,it is confirmed that implementing a partition wall can effectively reduce floor heave and enhance the stability of tunnel floor.

关键词： Layered rock Floor heave Horizontal compression test Failure behavior Partition wall

Rheological and stability analysis of cement pastes incorporating silica-based wastes

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Particuology 2024年第6期89卷 144-152页

作者： Julia da Rosa Martins Janaíde Cavalcante Rocha dachamir Hotza Luciano Senff Graduate Program in Materials Science and Engineering(PPGMAT) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Graduate Program in Civil Engineering(PPGEC) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Graduate Program in Chemical Engineering(POSENQ) Federal University of Santa Catarina(UFSC)Florianópolis88040-900SCBrazil Department of Mobility Engineering Federal University of Santa Catarina(UFSC)Joinville89219-600SCBrazil

This study investigates the influence of waste characteristics,especially zeta potential,on the properties of cement pastes and *** focus is to evaluate the impact of the zeta potential of cement particles and waste materials on the sedimentation speed,rheology,and hardening time of stabilized cement *** Cement ii F 40,retarder additive,silica,and fly ash were used in the *** pastes were prepared,and during the stabilization period,their rheological properties and pH were *** zeta potential and sedimentation speed of the cement and waste particles were measured at the pH that the pastes presented during the entire stabilization *** the stabilization period,the pastes were subjected to the hardening time *** zeta potential analyses revealed diverse values for the different powder types,with the cement particles exhibiting a zeta potential of−3.0 mV,the silica particles exhibiting−10.5 mV,and the fly ash particles exhibiting−20.3 *** influence of the high zeta potential modulus was observed on the sedimentation speed,with the solution containing fly ash exhibiting a speed of 40.01μm/s,whereas the solution containing only cement exhibited a speed of 99.38μm/*** the pastes,the results indicate that the presence of fly ash particles with a significantly negative zeta potential led to a 16%reduction in hardening time compared to particles with a lower modulus of zeta *** tests showed that the inclusion of fly ash particles prevented the formation of *** the zeta potential influenced agglomerate formation and hardening time,it was found to have no effect on yield stress or viscosity.

关键词： Wastes Zeta potential Setting time Rheometry

Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

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Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying Wang Shengling Si Hongli Li david da Yong Chen National institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Si Chuan Zhong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment *** effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of *** affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were *** optimum conditions were found to be 120℃,10 min,and 3 cycles,***-MS/MS method was developed to obtain the optimal sensitivity specific to *** method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/*** ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent *** optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target ***,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to *** is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressurized liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control

Resource management at the network edge for federated learning

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Digital Communications and Networks 2024年第3期10卷 765-782页

作者： Silvana Trindade Luiz F.Bittencourt Nelson L.S.da Fonseca institute of Computing State University of CampinasCampinasBrazil

Federated learning has been explored as a promising solution for training machine learning models at the network edge,without sharing private user *** limited resources at the edge,new solutions must be developed to leverage the software and hardware resources as the existing solutions did not focus on resource management for network edge,specially for federated *** this paper,we describe the recent work on resource manage-ment at the edge and explore the challenges and future directions to allow the execution of federated learning at the *** such as the discovery of resources,deployment,load balancing,migration,and energy effi-ciency are discussed in the paper.

关键词： Resource management Edge computing Federated learning Machine learning

Sustainable electrosynthesis: Enantioselective electrochemical Rh(Ⅲ)/chiral carboxylic acid-catalyzed oxidative C–H cyclization coupled with hydrogen evolution reaction

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Chinese Chemical Letters 2024年第9期35卷 1-3页

作者： Xinghui Yao Zhouyu Wang da-Gang Yu Department of Chemistry Xihua UniversityChengdu 610039China Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China

Chiral compounds play a crucial role in the development of pharmaceuticals,pesticides,fragrances,and materials due to their unique stereochemical *** catalysis,which employs chiral catalysts to favor the production of one enantiomer over its mirror image,has emerged as a pivotal technique in the synthesis of chiral compounds[1].However,traditional asymmetric methods sometimes rely on environmentally harmful reducing or oxidizing agents,presenting a considerable challenge in the pursuit of green chemistry.

关键词： chiral oxidative catalyzed