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Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted T-beams

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahmed M.ATTA Reda n.BEHIRY Mohammed I.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt nile Higher Institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beams have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-T beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted T-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened RC inverted T-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： RC bridges inverted T-beams strengthening hanger failure external prestressing

Hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas

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Avian Research 2024年第1期15卷 91-97页

作者： nora Agh Henriett Anna Dalvári Krisztián Szabó Ivett Pipoly András Liker HUn-REn-PE Evolutionary Ecology Research Group University of PannoniaH-8200VeszpremPf.1158.Hungary Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaH-8200Pf.1158.VeszpremHungary Molecular Ecology Research Group Department of EcologyUniversity of Veterinary Medicine BudapestH-1400Pf.2.BudapestHungary Synlab Hungary Ltd. H-1211Weiss Manfr´ed Str.5-7BudapestHungary

Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex *** extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and *** areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in *** test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and *** ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(ng did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study *** results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages.

关键词： Great Tit Urbanization nestling mortality Sex related differences

In-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián Máthis Péter nagy Péter Jenei Zoltán Hegedus Andrea Farkas Jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of Materials Physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of Physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CAnaPs),or complete long period stacking ordered(LPSO)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CAnaPs/LPSO plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered(LPSO)phase Cluster arranged nanoplates(CAnaPs) Annealing Tension Dislocation density Hardening

Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Journal of Forestry Research 2024年第2期35卷 70-80页

作者： Aleksey S.Ilintsev Elena n.nakvasina Alexander P.Bogdanov northern Research Institute of Forestry 13 Nikitova Str.Arkhangelsk 163062Russian Federation Department of Silviculture and Forest Management Northern(Arctic)Federal University Named After M.V.LomonosovSevernoy Dviny Emb.17Arkhangelsk 163002Russian Federation

This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of *** study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess *** the rooting layer,240 soil samples were taken to determine physical *** study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina ***,reduced soil moisture was noted,particularly in mounds,resulting in increased *** Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the *** treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration *** the Myrtillus and Polytrichum sites,patch scarification had no effects on physical *** Polytrichum sites,survival rates,heights,and heigh increments of bareroot norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to *** Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil *** conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.

关键词： Boreal forests Mechanical site preparation Patch scarification Mounding Soil properties Containerised seedlings Bareroot seedlings

Liquid crystal immunosensors for the selective detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： SAnDRO C.OLIVEIRA MARIA S.SOARES BÁRBARA V.GOn.alves AnDREIA C.M.RODRIGUES AMADEU M.V.M.SOARES RITA G.SOBRAL nUnO F.SAnTOS JAn nEDOMA PEDRO L.ALMEIDA CARLOS MARQUES CICECO-Aveiro Institute of Materials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3n Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate Laboratory i4HB-Institute for Health and Bioeconomy School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal CESAM-Centre for Environmental and Marine Studies and Department of Biology University of Aveiro3810-193 AveiroPortugal Department of Telecommunications VSB-Technical University of OstravaOstrava 70800Czech Republic i3n-CEnIMAT School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Department of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consumption of contaminated food may cause serious illnesses,and traditional methods to detect Escherichia coli are still associated with long waiting times and high costs given the necessity to transport samples to specialized *** is a need to develop new technologies that allow cheap,fast,and direct monitoring at the site of ***,in this work,we developed optical immunosensors for the selective detection of ***,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the environment that they *** glass substrate was functionalized with *** antibody using cysteamine as an intermediate,and a vertical alignment was imposed on the liquid crystal molecules by using DMOAP during *** presence of bacteria disrupts the alignment of the liquid crystal molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical microscope and a *** was possible to detect *** in suspensions in the concentration range from 2.8 cells/mL to 2.8×10^(9) cells∕*** was also evaluated,and the sensors were used to analyze contaminated water samples.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instruments.

关键词： crystal alignment analysis

Comparison of Perovskite Systems Based on AFeO_(3)(A=Ce,La,Y)in CO_(2) Hydrogenation to CO

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Transactions of Tianjin University 2024年第4期30卷 337-358页

作者： Anna n.Matveyeva Shamil O.Omarov Laboratory of Materials and Processes for Hydrogen Energy Ioff e Institute194021 St.PetersburgRussia

CO_(2) is the most cost-eff ective and abundant carbon resource,while the reverse water-gas reaction(rWGS)is one of the most eff ective methods of CO_(2) *** work presents a comparative study of rWGS activity for perovskite systems based on AFeO_(3)(where A=Ce,La,Y).These systems were synthesized by solution combustion synthesis(SCS)with diff erent ratios of fuel(glycine)and oxidizer(φ),diff erent amounts of nH 4 nO_(3),and the addition of alumina or silica as *** techniques,including X-ray diff raction analysis,thermogravimetric analysis,Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy,energy-dispersive X-ray spectroscopy,n 2-physisorption,H_(2) temper-ature-programmed reduction,temperature-programmed desorption of H_(2) and CO_(2),Raman spectroscopy,and in situ FTIR,were used to relate the physicochemical properties with the catalytic performance of the obtained *** specifi c perovskite-containing system(either bulk or supported)has its own optimalφand nH_(4) nO_(3) amount to achieve the highest yield and dispersion of the perovskite *** all synthesized systems,bulk SCS-derived La-Fe-O systems showed the highest resistance to reducing environments and the easiest hydrogen desorption,outperforming La-Fe-O produced by solgel combustion(SGC).CO_(2) conversion into CO at 600°C for bulk ferrite systems,depending on the A-cation type and preparation method,follows the order La(SGC)nces in properties between La-Fe-O obtained by the SCS and SGC methods can be attributed to diff erent ratios of oxygen and lanthanum vacancy contributions,hydroxyl coverage,morphology,and free iron oxide *** situ FTIR data revealed that CO_(2) hydrogenation occurs through formates generated under reaction conditions on the bulk system based on La-Fe-O,obtained by the SCS method.γ-Al_(2)O_(3) improves the dispersion of CeFeO_(3) and LaFeO_(3) phases,the specifi c surface area,and the quant

关键词： Perovskites LaFeO_(3) CeFeO_(3) YFeO_(3) Solution combustion synthesis CO_(2) hydrogenation Reverse water–gas reaction(rWGS)

numerical Simulation of Thermocapillary Convection with Evaporation Induced by Boundary Heating

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1667-1686页

作者： O.n.Goncharova V.B.Bekezhanova Altai State University Institute of Mathematics and Information TechnologiesBarnaul656049Russia Institute of Computational Modelling SB RAS Department of Differential Equations of MechanicsKrasnoyarsk660036Russia

The dynamics of a bilayer system filling a rectangular cuvette subjected to external heating is *** influence of two types of thermal exposure on the flow pattern and on the dynamic contact angle is *** particular,the cases of local heating from below and distributed thermal load from the lateral walls are *** simulation is carried out within the frame of a two-sided evaporative convection model based on the Boussinesq approximation.A benzine–air system is considered as reference *** variation in time of the contact angle is described for both heating *** lateral heating,near-wall boundary layers emerge together with strong convection,whereas the local thermal load from the lower wall results in the formation of multicellular motion in the entire volume of the fluids and the appearance of transition regimes followed by a steady-state *** results of the present study can aid the design of equipment for thermal coating or drying and the development of methods for the formation of patterns with required structure and morphology.

关键词： Thermocapillary convection two-phase system numerical modeling contact angle

A Probabilistic Trust Model and Control Algorithm to Protect 6G networks against Malicious Data Injection Attacks in Edge Computing Environments

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 631-654页

作者： Borja Bordel Sánchez Ramón Alcarria Tomás Robles Department of Computer Systems Universidad Politécnica de MadridMadrid28031Spain Department of Geospatial Engineering Universidad Politécnica de MadridMadrid28031Spain

Future 6G communications are envisioned to enable a large catalogue of pioneering *** will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control loops critical for managing Industry 5.0 deployments,digital agriculture systems,and essential *** provision of extensive machine-type communications through 6G will render many of these innovative systems autonomous and *** full automation will enhance industrial efficiency significantly,it concurrently introduces new cyber risks and *** particular,unattended systems are highly susceptible to trust issues:malicious nodes and false information can be easily introduced into control ***,Denialof-Service attacks can be executed by inundating the network with valueless *** anomaly detection schemes require the entire transformation of the control software to integrate new steps and can only mitigate anomalies that conform to predefined mathematical *** based on an exhaustive data collection to detect anomalies are precise but extremely *** models,with their limited understanding of mobile networks,can achieve precision rates no higher than 75%.Therefore,more general and transversal protection mechanisms are needed to detect malicious behaviors *** paper introduces a probabilistic trust model and control algorithm designed to address this *** model determines the probability of any node to be *** channels are pruned for those nodes whose probability is below a given *** trust control algorithmcomprises three primary phases,which feed themodel with three different probabilities,which are weighted and ***,anomalous nodes are identified using Gaussian mixture models and clustering ***,traffic patterns are studied using digital Bessel functions and the functional scalar ***,the in

关键词： 6G networks noise injection attacks Gaussian mixture model Bessel function traffic filter Volterra filter

Fast and Accurate Predictor-Corrector Methods Using Feedback-Accelerated Picard Iteration for Strongly nonlinear Problems

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1263-1294页

作者： Xuechuan Wang Wei He Haoyang Feng Satya n.Atluri School of Astronautics Northwestern Polytechnical UniversityXi’an710072China Department of Mechanical Engineering Texas Tech UniversityLubbock79409USA

Although predictor-corrector methods have been extensively applied,they might not meet the requirements of practical applications and engineering tasks,particularly when high accuracy and efficiency are necessary.A novel class of correctors based on feedback-accelerated Picard iteration(FAPI)is proposed to further enhance computational *** optimal feedback terms that do not require inversion of matrices,significantly faster convergence speed and higher numerical accuracy are achieved by these correctors compared with their counterparts;however,the computational complexities are comparably *** advantages enable nonlinear engineering problems to be solved quickly and accurately,even with rough initial guesses from elementary *** proposed method offers flexibility,enabling the use of the generated correctors for either bulk processing of collocation nodes in a domain or successive corrections of a single node in a finite difference *** our method,the functional formulas of FAPI are discretized into numerical forms using the collocation *** collocated iteration formulas can directly solve nonlinear problems,but they may require significant computational resources because of the manipulation of *** address this,the collocated iteration formulas are further converted into finite difference forms,enabling the design of lightweight predictor-corrector algorithms for real-time *** generality of the proposed method is illustrated by deriving new correctors for three commonly employed finite-difference approaches:the modified Euler approach,the Adams-Bashforth-Moulton approach,and the implicit Runge-Kutta ***,the updated approaches are tested in solving strongly nonlinear problems,including the Matthieu equation,the Duffing equation,and the low-earth-orbit tracking *** numerical findings confirm the computational accuracy and efficiency of the derived predictor-correc

关键词： Predictor-corrector method feedback-accelerated Picard iteration nonlinear dynamical system real-time computation