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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

Influence of indoor airflow on airborne disease transmission in a classroom

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Building simulation 2024年第3期17卷 355-370页

作者： Mojtaba Zabihi ri Li Joshua Brinkerhoff school of Engineering Faculty of Applied ScienceUniversity of British ColumbiaKelownaCanada

It has been widely accepted that the most effective way to mitigate airborne disease transmission in an indoor space is to increase the ventilation airflow,measured in air change per hour(ACH).However,increasing ACH did not effectively prevent the spread of *** better understand the role of ACH and airflow large-scale patterns,a comprehensive fully transient computational fluid dynamics(CFD)simulation of two-phase flows based on a discrete phase model(DpM)was performed in a university classroom setting with people *** investigations encompass various particle sizes,ventilation layouts,and flow *** findings demonstrated that the particle size threshold at which particles are deemed airborne is highly influenced by the background flow strength and large-scale flow pattern,ranging from 5µm to 10µm in the cases *** effects of occupants are significant and must be precisely accounted for in respiratory particle transport *** enhanced ventilation design(UFAD-CDR)for university classrooms is introduced that places a premium on mitigating airborne disease *** to the baseline design at the same ACH,this design successfully reduced the maximum number density of respiratory particles by up to 85%.A novel airflow-related parameter,Horizontality,is introduced to quantify and connect the large-scale airflow pattern with indoor aerosol *** underscores that ACH alone cannot ensure or regulate air *** addition to the necessary ACH for air exchange,minimizing horizontal bulk motion is essential for reducing aerosol transmissibility within the room.

关键词： aerosol transmission airflow pattern horizontality COVID-19 simulation classroom ventilation

Emission colour tuning in kLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)phosphor

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Journal of Rare Earths 2024年第1期42卷 57-65,I0002页

作者： Janani k Gayathri E Vijayatha V Ramasubramanian s Thiyagarajan p Department of science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of physics Anna UniversityChennaiIndia

kLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/Er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth Er/Ho doped kYbF4shows strong red emission compared to other ***_(4):Yb,Er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,Er-doped kGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped kYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths Energy transfer upconversion Downshifting Colour coordinates

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： Bao-ri Zhang Yong-Hua shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong provincial Engineering Research Center for special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： plasma arc additive manufacturing(pAAM) Weld pool geometry Gradient analysis Real-time detection

Challenging the term symbiosis in plant-microbe associations to create an understanding across sciences

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Journal of Integrative plant Biology 2024年第1期66卷 7-11页

作者： Anna Neubauer Daniela Aros‐Mualin Vicente Mariscal péter szövényi Department of systematic and Evolutionary Botany University of ZurichZurich 8008Switzerland Zurich‐Basel plant science Center Zurich 8092Switzerland Instituto de Bioquímica Vegetal y Fotosíntesis CSIC y Universidad de SevillaSevilla 41092Spain

THE IMpORTANCE OF WELL DEFINED terMINOLOGY,Effective communication across fields and disciplines relies on well defined *** use of accurate definitions has been advocated by scientists across various disciplines(pysek... 详细信息

关键词： terminology definition fields

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(s old,59.0%males).However,the sex ratios of dead offspring 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

Optimal risk sharing for Maxmin Choquet Expected Utility Model

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Acta Mathematicae Applicatae sinica 2024年第2期40卷 430-444页

作者： De-jian TIAN shang-ri WU school of Mathematics China University of Mining and TechnologyXuzhou 221116China

This article analyzes the pareto optimal allocations,agreeable trades and agreeable bets under the maxmin Choquet expected utility(MCEU)*** provide several useful characterizations for pareto optimal allocations for risk averse *** derive the formulation descriptions for non-existence agreeable trades or agreeable bets for risk neutral *** build some relationships between ex-ante stage and interim stage on agreeable trades or bets when new information arrives.

关键词： maxmin Choquet expected utility model pareto optimal allocation agreeable trade agreeable bet

Effects of neoadjuvant chemotherapy vs chemoradiotherapy in the treatment of esophageal adenocarcinoma:A systematic review and meta-analysis

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World Journal of Gastroenterology 2024年第11期30卷 1621-1635页

作者： Armand Csontos Alíz Fazekas Lajos szakó Nelli Farkas Csenge papp szilárd Ferenczi szabolcs Bellyei péter Hegyi András papp Department of surgery University of PécsMedical SchoolClinical CenterPécs H-7624BaranyaHungary Institute of Bioanalysis University of PécsMedical SchoolPécs H-7624BaranyaHungary Institute for Translational Medicine University of PécsMedical SchoolPécs H-7624BaranyaHungary Department of Emergency Medicine Clinical CenterUniversity of PécsMedical SchoolPécs 7624BaranyaHungary Department of Oncotherapy University of PécsMedical SchoolClinical CenterPécs H-7624BaranyaHungary Centre for Translational Medicine Semmelweis UniversityBudapest 1085Hungary Institute of pancreatic Diseases Semmelweis UniversityBudapest H-1083Hungary

BACkGROUND Neoadjuvant therapy is an essential modality for reducing the clinical stage of esophageal cancer;however,the superiority of neoadjuvant chemotherapy(nCT)or neoadjuvant chemoradiotherapy(nCRT)is ***,a discussion of these two modalities is *** To investigate the benefits and complications of neoadjuvant *** To address this concern,predefined criteria were established using the pICO *** independent authors performed comprehensive searches using predetermined *** analyses were performed to identify significant differences between *** publication bias was visualized using funnel *** quality of the data was evaluated using the risk of Bias Tool 2(RoB2)and the GRADE *** Ten articles,including 1928 patients,were included for the *** difference was detected in pathological complete response(pCR)[ps ratio(OR):0.27;95%CI:0.16-0.46],30-d mortality(p=0.015;OR:0.4;95%CI:0.22-0.71)favoring the nCRT,and renal failure(p=0.039;OR:1.04;95%CI:0.66-1.64)favoring the *** significant differences were observed in terms of survival,local or distal recurrence,or other clinical or surgical *** result of RoB2 was moderate,and that of the GRADE approach was low or very low in almost all *** Although nCRT may have a higher pCR rate,it does not translate to greater long-term ***,nCRT is associated with higher 30-d mortality,although the specific cause for postoperative complications could not be *** the case of nCT,toxic side effects are suspected,which can reduce the quality of *** the quality of available studies,further randomized trials are required.

关键词： Neoadjuvant Chemotherapy Chemoradiotherapy Esophageal cancer Adenocarcinoma

Optimum profiles of Endwall Contouring for Enhanced Net Heat Flux Reduction and Aerodynamic performance

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Journal of Harbin Institute of Technology(New series) 2024年第2期31卷 80-92页

作者： Arjun k s Tide p s Biju N Division of Mechanical Engineering School of EngineeringCochin University of Science&TechnologyKalamassery 682022India

successfully utilized non-axisymmetric endwalls to enhance turbine efficiencies(aerodynamic and turbine inlet temperatures)by controlling the characteristics of the secondary flow in a blade *** is accomplished by steady-state numerical hydrodynamics and deep knowledge of the field of *** of the interaction between mainstream and purge flow contributing supplementary losses in the stage,non-axisymmetric endwalls are highly susceptible to the inception of purge flow exit compared to the flat and any advantage rapidly *** conclusions reveal that the supreme endwall pattern could yield a lowering of the gross pressure loss at the design stage and is related to the size of the top-loss location being productively *** has led to diminished global thermal exchange lowered in the passage of the vane *** reverse flow adjacent to the suction side corner of the endwall is migrated farther from the vane surface,as the deviated pressure spread on the endwall accelerates the flow and progresses the reverse flow core still *** depleted association between the tornado-like vortex and the corner vortex adjacent to the suction side corner of the endwall is the dominant mechanism of control in the contoured end *** this publication,we show that the non-axisymmetric endwall contouring by selective numerical shape change method at most prominent locations is advantageous in lowering the thermal load in turbines to augment the net heat flux reduction as well as the aerodynamic performance using multi-objective optimization.

关键词： endwall contouring turbine vane heat transfer phantom cooling coolant injection net heat flux reduction aerodynamic performance