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Ferroelectricity Induced by Oxygen Vacancies in Rhombohedral ZrO_(2) Thin Films

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Energy & Environmental materials 2024年第1期7卷 229-237页

作者： Veniero Lenzi José P.B.silva Břetislav Šmíd Vladimir matoín Cosmin m.Istrate Corneliu Ghica Judith L.macmanus-Driscoll Luís marques Physics Center of minho and Porto Universities(CF-Um-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal Laboratory of Physics for materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of surface and Plasma science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of materials Physics 105 bis Atomistilor 077125Magurele Romania Department of materials science and metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observed in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contribute to the ferroelectric *** findings reveal the importance of V_(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

Rare earth based mgPm_(2)X_(4)(X=s,se) spinel chalcogenides for spintronic and thermoelectric applications

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Journal of Rare Earths 2024年第8期42卷 1577-1585,I0006页

作者： Tariq m.Al-Daraghmeh Omar Zayed Ghulam m.mustafa Taharh Zelai Bisma Younas Hind Albalawi s.Bouzgarrou Othman Hakami Q.mahmood Khaild I.Hussein Basic sciences Department King Abdullah Ⅱ School of EngineeringPrincess Sumaya University For TechnologyP.O.Box 1438Al-jubaiha11941AmmanJordan Department of Physics Division of Science&TechnologyUniversity of EducationLahorePakistan Department of Physics Faculty of ScienceJazan University JazanSaudi Arabia Department of Physics The University of LahoreLahorePakistan Department of Physics College of SciencesPrincess Nourah bint Abdulrahman University(PNU)P.O.Box 84428Riyadh11671Saudi Arabia Department of Physics College of ScienceQassim UniversityPo.64BuraidahSaudi Arabia Laboratoire de microelectronique et Instrumentation(UR 03/13-04) Faculte des Sciences de MonastirAvenue de I'Environnement 5000MonastirTunisia Department of Chemistry Faculty of ScienceJazan University JazanSaudi Arabia Basic&Applied scientific Research Center Department of PhysicsCollege of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam 31441Saudi Arabia Department of Radiological sciences College of Applied Medical SciencesKing Khalid UniversityAbha61421Saudi Arabia

In current report,the structural,magnetic,and thermoelectric properties of RE doped mgPm_(2)X_(4)(X=s,se) spinels were *** energy difference in ferromagnetic and antiferromagnetic states reveals the stability of mgPm_(2)(s/se)_(4) in the ferromagnetic *** co mputation of enthalpy of formation also ascertains thermodynamic stability of crystal ***-dependent band structure and density of states analysis reveal ferromagnetic semiconducting character showing different electronic behavior in both spin *** room temperature ferromagnetism,spin polarization and Curie temperature are estimated from exchange energies *** addition,exchange constants(N_(0)α and N_(0)β),exchange energy Δ_(x)(pd),crystal ifeld energy,and double exchange mechanism were studied to explore the magnetic ***,the electrical conductivity,thermal conductivity,seebeck co-efficient,and power factor show effect on electrons spin and their potential for thermoelectric devices.

关键词： Rare earth elements spintronic applications Thermoelectric effects Exchange energies

A review on transition metal oxides based photocatalysts for degradation of synthetic organic pollutants

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Journal of Environmental sciences 2024年第5期139卷 389-417页

作者： Athira Krishnan Anna swarnalal Divine Das midhina Krishnan Viswanathan s.saji smAshibli Department of Chemistry Amrita Vishwa VidyapeethamAmritapuriKerala690525India Interdisciplinary Research Center for Advanced materials King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Chemistry University of KeralaKariavattom CampusThiruvananthapuramKerala695581India

This review provides insight into the current research trend in transition metal oxides(TmOs)-based photocatalysis in removing the organic colouring matters from *** easy understanding,the research progress has been presented in four generations according to the catalyst composition and mode of application,viz:single component TmOs(the firstgeneration),doped TmOs/binary TmOs/doped binary TmOs(the second-generation),inactive/active support-immobilized TmOs(the third-generation),and ternary/quaternary compositions(the fourth-generation).The first two generations represent suspended catalysts,the third generation is supported catalysts,and the fourth generation can be suspended or *** review provides an elaborated comparison between suspended and supported catalysts,their general/specific requirements,key factors controlling degradation,and the methodologies for performance *** the plausible fundamental and advanced dye degradation mechanisms involved in each generation of catalysts were *** existing challenges in TmOs-based photocatalysis and how the researchers approach the hitch to resolve it effectively are *** research trends are also presented.

关键词： Photocatalysis Dye degradation Transition metal oxides and composites supported catalysts suspended catalysts

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.morassuti A.P.L silva L.A.O.Nunes s.m.Lima L.H.C.Andrade Optical and Photothermal spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： U.s.mahabaleshwar G.P.Vanitha L.m.Pérez Emad H.Aly I.Pop Department of studies in mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

metrology for sub-Rayleigh-length target positioning in~10^(22)W/cm^(2)laser-plasma experiments

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High Power Laser science and Engineering 2024年第3期12卷 90-105页

作者： E.A.Vishnyakov A.sagisaka K.Ogura T.Zh.Esirkepov B.Gonzalez-Izquierdo C.D.Armstrong T.A.Pikuz s.A.Pikuz W.Yan T.m.Jeong s.singh P.Hadjisolomou O.Finke G.m.Grittani m.Nevrkla C.m.Lazzarini A.Velyhan T.Hayakawa Y.Fukuda J.K.Koga m.Ishino K.Kondo Y.miyasaka A.Kon m.Nishikino Y.V.Nosach D.Khikhlukha I.P.Tsygvintsev D.Kumar J.Nejdl D.margarone P.V.sasorov s.Weber m.Kando H.Kiriyama Y.Kato G.Korn K.Kondo s.V.Bulanov T.Kawachi A.s.Pirozhkov ELI Beamlines Facility The Extreme Light Infrastructure ERICDolníBrežanyCzech Republic Kansai Institute for Photon science(KPsI) QSTKyotoJapan Central Laser Facility Rutherford Appleton LaboratorySTFCHarwell OxfordDidcotUK Institute for Open and Transdisciplinary Research Initiatives Osaka UniversityOsakaJapan HB11 Energy Holdings FreshwaterAustralia Key Laboratory for Laser Plasmas(ministry of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFsA Shanghai Jiao Tong UniversityShanghaiChina Institute of Plasma Physics AsCR PragueCzech Republic FZU-Institute of Physics AsCR PragueCzech Republic Czech Technical University in Prague FNSPEPragueCzech Republic Institute of Laser Engineering Osaka UniversityOsakaJapan Institute of Physics National Academy of Sciences of UkraineKyivUkraine IsTEQ AR YerevanArmenia

Tight focusing with very small f-numbers is necessary to achieve the highest at-focus ***,tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance We describe several near-infrared,visible,ultraviolet and soft and hard X-ray diagnostics employed in a~10^(22)W/cm^(2)laser±plasma *** used nearly 10 J total energy femtosecond laser pulses focused into an approximately1.3-μm focal spot on 5±20μm thick stainless-steel *** discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5μm accuracy(i.e.,around half of the short Rayleigh length)and show that several diagnostics(in particular,3ωreflection and on-axis hard X-rays)can ensure this *** demonstrated target positioning within several micrometers from the focus,ensuring over 80%of the ideal peak laser intensity *** approach is relatively fast(it requires 10±20 laser shots)and does not rely on the coincidence of low-power and high-power focal planes.

关键词： laser-plasma interaction precise target positioning spectroscopy ultra-high intensity X-rays

An Investigation into Forced Convection of a Nanofluid Flowing in a Rectangular microchannel under the Influence of a magnetic Field

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Fluid Dynamics & materials Processing 2024年第2期20卷 311-323页

作者： muataz s.Alhassan Ameer A.Alameri Andrés Alexis Ramírez-Coronel I.B.sapaev Azher m.Abed David-Juan Ramos-Huallpartupa Rahman s.Zabibah Division of Advanced Nanomaterial Technologies Scientific Research CenterAl-Ayen UniversityThi-QarIraq Department of Chemistry College of ScienceUniversity of BabylonBabylonIraq Research Group in Educational statistics National University of EducatiosnAzoguesEcuador Department Physics and Chemistry Tashkent Institute of Irrigation and Agricultural Mechanization EngineersNational Research UniversityTashkentUzbekistan Akfa University TashkentUzbekistan New Uzbekistan University TashkentUzbekistan Department of Airconditioning and Refrigeration Engineering Al-Mustaqbal University CollegeHilla51001Iraq Academic Department of Agro-Industrial Engineering and Technology Universidad Nacional JoséMaría ArguedasApurimacPerú The Islamic University NajafIraq

In line with recent studies,where it has been shown that nanoﬂuids containing graphene have a stronger capacity to boost the heat transfer coefﬁcient with respect to ordinary nanoﬂuids,experiments have been conducted using water with cobalt ferrite/graphene *** particular,a circular channel made of copper subjected to a constant heatﬂux has been *** nanoparticles are sensitive to the presence of a magneticﬁeld,different conditions have been examined,allowing both the strength and the frequency of such aﬁeld to span relatively wide ranges and assuming different concentrations of *** to theﬁndings,the addition of nanoparticles to theﬂuid causes its rotation speed to increase by a factor of two,whereas ultraviolet radiation plays a negligible *** amount of time required to attain the maximum rotation speed of the nanoﬂuid and the Nusselt number have been measured under both constant and alternating magneticﬁelds for a ferroﬂuid with a concentration of 0.5%and atﬂow Reynolds number of 550 and 1750.

关键词： Nano fluid rectengular tube magnetic field

Irisin/BDNF signaling in the muscle-brain axis and circadian system: A review

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The Journal of Biomedical Research 2024年第1期38卷 1-16页

作者： Alexey N.Inyushkin Vitalii s.Poletaev Elena m.Inyushkina Igor s.Kalberdin Andrey A.Inyushkin Department of Human&Animal Physiology Samara National Research UniversitySamara 443011Russia.

In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian *** entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus to a precise 24-h rhythm,environmental zeitgebers are used by the circadian *** is done primarily by signals from the retina via the retinohypothalamic tract,but other cues like exercise,feeding,temperature,anxiety,and social events have also been shown to act as non-photic *** recently identified myokine irisin is proposed to serve as an entraining non-photic signal of *** is a product of cleavage and modification from its precursor membrane fibronectin typeⅢdomain-containing protein 5(FNDC5)in response to *** from well-known peripheral effects,such as inducing the"browning"of white adipocytes,irisin can penetrate the blood-brain barrier and display the effects on the *** data suggest that FNDC5/irisin mediates the positive effects of physical activity on brain *** several brain areas,irisin induces the production of brain-derived neurotrophic factor(BDNF).In the master clock,a significant role in gating photic stimuli in the retinohypothalamic synapse for BDNF is ***,the brain receptor for irisin remains *** the current review,the interactions of physical activity and the irisin/BDNF axis with the circadian system are reconceptualized.

关键词： irisin brain-derived neurotrophic factor peroxisome proliferator-activated receptorγcoactivator 1α circadian rhythm circadian system muscle-brain axis

Robust Facial Biometric Authentication system Using Pupillary Light Reflex for Liveness Detection of Facial Images

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Computer modeling in Engineering & sciences 2024年第4期139卷 725-739页

作者： Puja s.Prasad Adepu sree Lakshmi sandeep Kautish simar Preet singh Rajesh Kumar shrivastava Abdulaziz s.Almazyad Hossam m.Zawbaa Ali Wagdy mohamed CsE Department Geethanjali College of EngineeringHyderabadTelangana501301India Department of Computer science LBEF CampusKathmandu44600Nepal school of Computer science Engineering and Technology(sCsET) Bennett UniversityGreater Noida201310India Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia CeADAR Ireland’s Centre for AI Technological University DublinDublinD07 EWV4Ireland Operations Research Department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Applied science Research Center Applied Science Private UniversityAmman11937Jordan

Pupil dynamics are the important characteristics of face spoofing *** face recognition system is one of the most used biometrics for authenticating individual *** main threats to the facial recognition system are different types of presentation attacks like print attacks,3D mask attacks,replay attacks,*** proposed model uses pupil characteristics for liveness detection during the authentication *** pupillary light reflex is an involuntary reaction controlling the pupil’s diameter at different light *** proposed framework consists of two-phase *** the first phase,the pupil’s diameter is calculated by applying stimulus(light)in one eye of the subject and calculating the constriction of the pupil size on both eyes in different video *** above measurement is converted into feature space using Kohn and Clynes model-defined *** support Vector machine is used to classify legitimate subjects when the diameter change is normal(or when the eye is alive)or illegitimate subjects when there is no change or abnormal oscillations of pupil behavior due to the presence of printed photograph,video,or 3D mask of the subject in front of the *** the second phase,we perform the facial recognition ***-invariant feature transform(sIFT)is used to find the features from the facial images,with each feature having a size of a 128-dimensional *** features are scale,rotation,and orientation invariant and are used for recognizing facial *** brute force matching algorithm is used for matching features of two different *** threshold value we considered is 0.08 for good *** analyze the performance of the framework,we tested our model in two Face antispoofing datasets named Replay attack datasets and CAsIA-sURF datasets,which were used because they contain the videos of the subjects in each sample having three modalities(RGB,IR,Depth).The CAsIA-sURF datasets showed an 89.9%Equal Err

关键词： sIFT pupil CAsIA-sURF pupillary light reflex replay attack dataset brute force