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Journal of Semiconductors 2024年第9期45卷 28-35页

作者： Leonarde N.Rodrigues Wesley f.Inoch Marcos L.f.Gomes Odilon D.D.Couto Jr. Bráulio S.Archanjo Sukarno O.ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

Modelling dynamic pantograph loads with combined numerical analysis

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Railway Engineering Science 2024年第1期32卷 81-94页

作者： f.f.Jackson R.Mishra J.M.Rebelo J.Santos P.Antunes J.Pombo H.Magalhaes L.Wills M.Askill School of Computing and Engineering University of HuddersfieldHuddersfieldUK School of Computing and Engineering Institute of Railway ResearchUniversity of HuddersfieldHuddersfieldUK IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal ISEL Instituto Politecnico de LisboaLisbonPortugal Hitachi Rail Newton AycliffeUK Wabtec/Brecknell Willis ChardUK

Appropriate interaction between pantograph and catenary is imperative for smooth operation of electric *** heights of overhead lines to accommodate level crossings,overbridges,and tunnels pose significant challenges in maintaining consistent current collection performance as the pantograph aerodynamic profile,and thus aerodynamic load changes significantly with operational *** research aims to analyse the global flow characteristics and aerodynamic forces acting on individual components of an HSX pantograph operating in different configurations and orientations,such that the results can be combined with multibody simulations to obtain accurate dynamic insight into contact ***,computational fluid dynamics simulations are used to investigate the pantograph component loads in a representative setting,such as that of the recessed cavity on a Class 800 *** an aerodynamic perspective,this study indicates that the total drag force acting on non-fixed components of the pantograph is larger for the knuckle-leading orientation rather than the knuckle-trailing,although the difference between the two is found to reduce with increasing pantograph *** the aerodynamic loads acting on individual components with multibody tools allows for realistic dynamic insight into the pantograph *** results obtained show how considering aerodynamic forces enhance the realism of the models,leading to behaviour of the pantograph-catenary contact forces closely matching that seen in experimental tests.

关键词： Pantograph-catenary interaction Pantograph aerodynamics Computational fluid dynamics Pantograph loads Current collection performance

Specific *** valorem taxation and social welfare in mixed duopoly with foreign ownership

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Economic and Political Studies 2024年第2期12卷 207-219页

作者： Ming Sun Leonard f.S.Wang Qidi Zhang School of Economics and Management Chang’an UniversityXi’anChina Wenlan School of Business Zhongnan University of Economics and LawWuhanChina

In this paper,we set up a mixed duopoly competition model between state-owned and private firms in order to compare specific and ad valorem *** that the total output under specific and ad valorem taxation remains unchanged,we find that if the public firm is completely privatised,the output of the private firm under the two tax schemes will be the *** the public firm is not completely privatised,the output of the the private firm under specific taxation will be greater than that under ad valorem *** the private firm is a pure local one,the social benefits will be the same under the two tax ***,if the private firm is a joint venture that involves domestic and foreign entities,social welfare under ad valorem taxation will be greater than that under specific taxation.

关键词： Specific taxation ad valorem taxation mixed duopoly imperfect competition privatisation foreign ownership

finite element analysis and experimental validation of polymer-metal contacts in block-on-ring configuration

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friction 2024年第3期12卷 554-568页

作者： K.Y.Eayal AWWAD Khosro fALLAHNEZHAD B.f.YOUSIf Ahmad MOSTAfA Omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analysis,obtained by different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study,the wear profile of polymer–metal contact,obtained by block-on-ring configuration under dry sliding conditions,was analysed using finite element modelling(fEM)and experimental ***’s wear equation was integrated into a developed fORTRAN-UMESHMOTION code linked with Abaqus software.A varying wear coefficient(k)values covering both running-in and steady state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** fEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify the critical zone where the stress concentration is the key point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately,SEM analysis showed severer damage features in the critical zone than that in the normal zone as proven by ***,the literature data presented and considered the wear features the same at any point of the wear *** this study,the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally different features from one another.

关键词： polymer-to-metal contact block-on-ring wear profile wear model

Sex differences in the risk of retinopathy of prematurity:a systematic review,frequentist and Bayesian meta‑analysis,and meta‑regression

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World Journal of Pediatrics 2024年第4期20卷 340-352页

作者： Tamara M.Hundscheid Silvia Gulden Mohamad f.Almutairi františek Bartoš Giacomo Cavallaro Eduardo Villamor Division of Neonatology Department of PediatricsMosaKids Children’s HospitalMaastricht University Medical Center(MUMC+)School for Oncology and Reproduction(GROW)Maastricht UniversityP.Debyelaan 25.P.O.Box 58006202 AZ MaastrichtThe Netherlands Neonatal Intensive Care Unit Sant’Anna HospitalComoItaly Department of Psychology University of Amsterdam1001 NK AmsterdamThe Netherlands Neonatal Intensive Care Unit Fondazione IRCCS Ca’Granda Ospedale Maggiore PoliclinicoMilanItaly

Background Retinopathy of prematurity(ROP)is generally considered to be more frequent in males than in ***,it is not known whether sex differences in ROP affect all degrees of the condition,are global and have changed as neonatology has *** aimed to conduct a systematic review and meta-analysis of studies addressing sex differences in the risk of developing *** PubMed/MEDLINE and Embase databases were *** frequentist,random-effects risk ratio(RR)and 95%confidence interval(CI)were *** model averaged(BMA)meta-analysis was used to calculate the Bayes factors(Bfs).The Bf10 is the ratio of the probability of the data under the alternative hypothesis(H1)over the probability of the data under the null hypothesis(H0).Results We included 205 studies(867,252 infants).frequentist meta-analysis showed a positive association between male sex and severe ROP(113 studies,RR=1.14,95%CI=1.07–1.22)but no association with any ROP(144 studies,RR=1.00,95%CI=0.96–1.03).BMA showed extreme evidence in favor of H1 for severe ROP(Bf10=71,174)and strong evidence in favor of H0 for any ROP(Bf10=0.05).The association between male sex and severe ROP remained stable over time and was present only in cohorts from countries with a high or high-middle sociodemographic *** Our study confirms the presence of a male disadvantage in severe ROP but not in less severe forms of the *** are variations in the sex differences in ROP,depending on geographical location and sociodemographic level of the countries.

关键词： Oxidative stress Retinopathy of prematurity Sex characteristics

Numerical Analysis of the Magnetic Dipole Effect on a Radiative ferromagnetic Liquid flowing over a Porous Stretched Sheet

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fluid Dynamics & Materials Processing 2024年第2期20卷 293-310页

作者： G.Dharmaiah f.Mebarek-Oudina K.S.Balamurugan N.Vedavathi Department of Mathematics Narasaraopeta Engineering CollegeNarasaraopetIndia Department of Physics Faculty of SciencesUniversity of 20 Août 1955-SkikdaSkikdaAlgeria Department of Mathematics RVR&JC College of EngineeringGunturIndia Department of Mathematics Koneru Lakshmaiah Education FoundationVaddeswaramIndia

The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidﬂowing over a stretched surface in the presence of Brownian motion and thermophoresis are *** means of a similarity transformation,ordinary differential equations are derived and solved afterwards using a numerical(the BVP4C)*** impact of various parameters,namely the velocity,temperature,concentration,is presented *** is shown that the nanoparticles properties,in conjunction with the magnetic dipole effect,can increase the thermal conductivity of the engineered nanoﬂuid and,consequently,the heat *** with earlier studies indicates high accuracy and effectiveness of the numerical *** increase in the Brow-nian motion parameter and thermophoresis parameter enhances the concentration and the related boundary *** skin-friction rises when the viscosity parameter is increased.A larger value of the ferromagnetic para-meter results in a higher skin-friction and,vice versa,in a smaller Nusselt number.

关键词： Brownian motion thermo-phoresis radiation magnetic dipole BVP4C non-linear

Dynamical study of varicella-zoster virus model in sense of Mittag-Leffler kernel

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International Journal of Biomathematics 2024年第3期17卷 153-183页

作者： Qura Tul Ain Aziz Khan Thabet Abdeljawad J.f.Gomez-Aguilar Saleem Riaz Department of Mathematics Guizhou University GuiyangGuizhou 550025P.R.China Department of Mathematics and Sciences Prince Sultan University P.O.Bor 66833 11586 RiyadhSaudi Arabia Department of Medical Research China Medical University Taichung 40402Taiwan CONACyT-Tecnologico Nacional de Mécico/CENIDET Interior Internado Palmira S/N Col.Palmira C.P.62490CuernavacaMorelosMécico IConsejo Academico Universidad Virtual CNCIMonterreyMécico School of Automation Northwestern Polytechnical University 170072 Xian P.R.China

The primary varicella-zoster virus(VzV)infection that causes chickenpox(also known as varicella),spreads quickly among people and,in severe circumstances,can cause to fever and *** this paper,the Mittag-Leffler fractional operator is used to examine the mathematical representation of the *** fractional-order differential equations are created in terms of the disease's dynamical analysis such as S:Susceptible,V:Vaccinated,E:Exposed,I:Infectious and R:*** derive the existence criterion,positive solution,Hyers-Ulam stability,and boundedness of results in order to examine the suggested fractional-order model's ***,some numerical examples for the VzV model of various fractional orders are shown with the aid of the generalized Adams-Bashforth-Moulton approach to show the viability of the obtained results.

关键词： Varicella-zoster virus model Hyers-Ulam stability ABC fractional operator Schauder fix point theory numerical analysis

Photofermentative hydrogen production by immobilized Rhodopseudomonas sp. S16-VOGS3 cells in photobioreactors

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Energy Reviews 2024年第1期3卷 39-48页

作者： Isabela C.Moia Aikaterini Kanaropoulou Demetrios f.Ghanotakis Pietro Carlozzi Eleftherios Touloupakis Research Institute on Terrestrial Ecosystems National Research CouncilVia Madonna del Piano 1050019Sesto FiorentinoFIItaly Department of Chemistry University of CreteVoutes Campus70013 HeraklionGreece

One of the most important solutions to overcome energy and environmental problems and to replace the fossil fuel-based economy could be the use of photosynthetic *** use of photosynthetic microorganisms is a potential alternative to energy generation from fossil fuels because they efficiently produce hydrogen(H_(2)).Immobilization of photosynthetic microorganisms is used for many biotechnological applications such as H_(2) *** method appears attractive because it restricts cell movement in an entrapped *** of Rhodopseudomonas sp.S16-VOGS3 cells is a promising way to improve H_(2) *** this work,the ability of immobilized Rhodopseudomonas sp.S16-VOGS3 cells to produce H_(2) was investigated in two types of *** PBRs used in this work were a cylindrical one with 0.2 L working volume(C-PBR)and a flat Roux type with 0.6 L working volume(fRT-PBR).The calcium alginate beads prepared were resistant to culture mixing and showed little leakage of cells,and the immobilized cells continued the photofermentation process in both *** immobilized cells in the C-PBR produced 936.8 mL of H_(2) with an average H_(2) production rate of 2.99 mL/*** average productivity was 126.4μL(H_(2))/mg(cells)/h or 14.96 mL(H_(2))/L(culture)/h,and the light conversion efficiency was 2.37%.The immobilized cells in the fRT-PBR produced a total of 662.2 mL of H_(2) with an average H_(2) production rate of 1.55 mL/*** average productivity was 31.1μL(H_(2))/mg(cells)/h or 2.58 mL(H_(2))/L(culture)/h,and the light conversion efficiency was 0.52%.The more uniform and therefore more efficient degree of bacterial cell mixing achieved in the C-PBR with cylindrical configuration played an important role compared to the *** the fRT-PBR,the beads were aggregated at the bottom,which limited light penetration and resulted in low H_(2) production efficiency.

关键词： Photobioreactor Rhodopseudomonas sp.S16-VOGS3 Photofermentation Hydrogen production Calcium alginate

Optimal Design of Hybrid Microgrid in Isolated Communities of Ecuador

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 488-499页

作者： Luis A.Pesantes Ruben Hidalgo-León Johnny Rengifo Miguel Torres Jorge Aragundi JoséCordova-Garcia Luis f.Ugarte facultad de Ingeniería en Electricidad y Computación of Escuela Superior Politécnica del Litoral(ESPOL)University GuayaquilEcuador Department of Electrical Engineering at Universidad Técnica federico Santa María SantiagoChile IEEE

In rural territories, the communities use energy sources based on fossil fuels to supply themselves with electricity, which may address two main problems: greenhouse gas emissions and high fuel prices. Hence, there is an opportunity to include renewable resources in the energy mix. This paper develops an optimization model to determine the optimal sizing, the total annual investment cost in renewable generation, and other operating costs of the components of a hybrid microgrid. By running a k-means clustering algorithm on a meteorological dataset of the community under study, the hourly representative values become input parameters in the proposed optimization model. The method for the optimal design of hybrid microgrid is analyzed in six operating scenarios considering:(1) 24-hour continuous power supply;(2) load shedding percentage;(3) diesel power generator(genset) curtailment;(4) the worst meteorological conditions;(5) the use of renewable energy sources including battery energy storage systems(BESSs);and(6) the use of genset. A mathematical programming language(AMPL) tool is used to find solutions of the proposed optimization model. Results show that the total costs of microgrid in the scenarios that cover 100% of the load demand(without considering the scenario with 100% renewables) increase by over 16% compared with the scenario with genset operation limitation. for the designs with power supply restrictions, the total cost of microgrid in the scenario with load shedding is reduced by over 27% compared with that without load shedding.

关键词： Battery energy storage system(BESS) isolated community microgrid renewable energy optimization

Canine on the Couch:The New Canary in the Coal Mine for Environmental Health Research

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Environment & Health 2024年第8期2卷 517-529页

作者： Catherine f.Wise Matthew Breen Heather M.Stapleton Nicholas School of the Environment Duke UniversityDurhamNorth Carolina 27708United States Duke Cancer Institute DurhamNorth Carolina 27710United States Department of Molecular Biomedical Sciences College of Veterinary MedicineNorth Carolina State University1060 William Moore DriveRaleighNorth Carolina 27607United States Comparative Medicine Institute North Carolina State UniversityRaleighNorth Carolina 27607United States Center for Human Health and the Environment North Carolina State UniversityRaleighNorth Carolina 27607United States

Human health is intimately connected and tied to the health of our environment and ecosystem,with only a very small fraction of the risk for chronic diseases explained by genetics *** animals are prone to disease types that are shared with people,including cancers and endocrine disorders,reinforcing the thought that environmental factors contribute to the risks for chronic *** factors include air and water pollution and the built *** such,there is increasing interest in pursuing research with companion animals,and specifically dogs,as sentinel species to inform comparative health assessments and identify risk factors for *** the canine diseases for which environmental exposure research has been published,cancers have received the most *** review summarizes two main aspects of this comparative approach:(1)cancers that occur in dogs and which are similar to humans and(2)research investigating environmental exposures and health outcomes in *** goal of this review is to highlight the diverse conditions in which pet dogs may provide unique perspectives and advantages to examine relationships between environmental exposures and health outcomes,with an emphasis on chemical pollution and ***,this review seeks to raise awareness and stimulate discussion around the best practices for the use of companion animals as environmental health sentinels.

关键词： sentinels dogs environmental health comparative oncology cancer alternative models environmental exposure