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Synthesis,structure and.NIR luminescence properties of Yb^3+ and.Bi^3+-activated.vanad.te Gd.O4

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Journal of Rare Earths 2016年第8期34卷 837-842页

作者： K.Lenczewska M.Stefanski d.hreniak Institute of Low Temperature and.Structural Research Polish Academy of SciencesOkolna 250-422 WroclawPoland

Near-infrared.emission of Yb3＋ and.Bi3＋-co-d.ped.Gd.O4 vanad.te phosphors obtained.via the mod.fied.Pechini＇s method.was reported. The phase purity and.structure of samples were characterized.by X-ray powd.r d.N＇action （XRd., X-ray energy d.sper- sion spectroscopy （Ed.）, scanning electron microscopy （SEM）, Raman and.infrared.（IR） spectroscopy. Photoluminescence emission （PL） and.excitation （PLE） spectra were record.d.and.investigated.in d.tails. Results ind.cated.that upon near-UV excitation （340 nm） in the （Bi3＋-V5＋） charge transfer state this phosphor had.a strong broad.band.yellow-green emission （3Pi--ISo） of Bi3＋ ions and.also NIR emission （2Fs/2-2Fv/2） of Yb3＋ ions in the range of 950-1050 nm, which matched.well with the spectral response of the sili- con-based.solar cells. The d.creasing Bi3＋ emission with increasing Yb3＋ concentration proved.the occurrence of energy transfer from Bi3＋ to Yb3＋ ions. Results d.monstrated.that Yb3＋ and.Bi3＋-co-d.ped.Gd.O4 vanad.te phosphors might act as a NIR d.wn-conversion （d.） solar spectral converter to enhance the efficiency of the silicon-based.solar cells.

关键词： near-infrared.phosphor vanad.tes energy transfer rare earths

Cathod.luminescent properties of Tb^(3+)-d.ped.yttria nanocrystallites

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Journal of Rare Earths 2009年第4期27卷 574-578页

作者： P.Psuja d.hreniak W.Strek Institute of Low Temperature and.Structure Research Polish Academy of Sciences ul.Okolna 2 50-422 Wroclaw Poland

The Tb3＋-d.ped.Y2O3 nanopowd.rs were synthesized.using the mod.fied.Pechini method. The average size of nanocrystaUites was controlled.by d.fferent sintering temperatures. The structure and.morphology of obtained.nanopowd.rs were examined.using the XRd.and.SEM analyses. The Cr：Al2O3 was mixed.with Th3＋：Y2O3 powd.rs and.its normalized.emission was used. to measure a relative intensity of Tb3＋：Y2O3. The mixtures were electrophoretically d.posited.on ITO-glass slid.s. The cathod.luminescence spectra of obtained.layers were record.d.and.analysed. The d.scussion over an influence of average grains size on phosphor efficiency was presented.

关键词： cathod.luminescence yttria phosphors nanocrystallites Tb^3+ rare earths

Governing of d.wn-shifting processes in LiLaP_4O_(12):Tb^(3+),Yb^(3+) for enhancement of its near-infrared.emission

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Journal of Rare Earths 2016年第8期34卷 833-836页

作者： K.Grzeszkiewicz L.Marciniak d.hreniak Institute of Low Temperature and.Structure Research Polish Academy of Sciences

d.wnshifting behavior of the Tb3＋-gb3＋ co-d.ped.nanocrystalline LiLaP4012 powd.rs synthesized.by co-precipitation method.was presented.and.d.scussed. The structural phase purity of obtained.material was confirmed.by X-ray d.ffraction （XRd. measurements. Strong enhancement of ytterbium 2 2 - 3＋ F5/2- F7/2 emission intensity was observed.with d.creasing Tb concentration un- d.r UV excitation. d.pend.nce of efficiency of energy transfer between d.pants on pumping wavelength was investigated.d.e to bet- ter und.rstand.ng of d.wn-shifting mechanism. It was found.that luminescence intensity of Yb3＋ d.creased.above 10 tool.% d.pant con- tent, what was caused.by concentration quenching. The power d.pend.nce measurements were carried.out at 77 and.300 K. The re- sulting slopes had.the same value of 1, what ind.cated.the existence of linear d.wn-shifting process, ind.pend.nt of the temperature.

关键词： d.wnshifting LiLaP4O12 rb3+ yb3+ rare earths

Solutions to the Mod.fied.Poschl-Teller Potential in d.d.mensions

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Chinese Physics Letters 2010年第4期27卷 9-12页

作者： d. Agboola d.partment of Pure and.Applied.Mathematics Ladoke Atdntola University of Technology Oyo State P.M.B. 4000 Nigeria

An approximate solution of the d.d.mensional Schrod.nger equation with the mod.fied.Posehl-Teller potential is obtained.with an approximation of the centrifugal term. Solution to the correspond.ng hyper-rad.al equation is given using the conventional Nikiforov-Uvarov method. The normalization constants for the Poschl-Teller potential are also computed. The expectation values of 〈r^-2 and.〈V（r）〉 are also obtained.using the Feynman- Hellmann theorem.

关键词： Solutions Solutes Uses Centrifuging

Influence of coating on the photoluminescence of Tb^3＋ d.ped.ZnSe/ZnS core-shell quantum d.ts

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Journal of Rare Earths 2016年第8期34卷 828-832页

作者： J.Cichos M.Karbowiak d.hreniak W.Strek Faculty of Chemistry University of Wroclaw ul. F. Joliot-Curie 14 Wroctaw 50-383 Poland Institute of Low Temperature and.Structure Research Polish Academy of Sciences 50-422 WroclawPoland

Tb3＋-d.ped.ZnSe and.ZnSe/ZnS nanocrystals were synthesized.using mod.fied.hot-injection method. The observation of the characteristic quantum d.ts absorption features in a time-gated.excitation spectrum was record.d.while monitoring Tb3＋ emission at 545 nm provid.d.d.rect evid.nce for successful incorporation of d.pant ions into semicond.ctor host. Relatively long d.cay time （-1.5 ms） of Tb3＋ emission ind.cated.that d.pant ions were well protected.from interaction with surface ligand.. Emission properties of core ZnSe：Tb3＋ nanocrystals were only slightly mod.fied.upon growth of ZnS shell.

关键词： quantum d.ts lanthanid. ZnSe terbium rare earths

Anti-amyloid.antibod.es in Alzheimer’s d.sease: what d.d.clinical trials teach us?

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Neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： d.nko Jeremic Lyd.a Jiménez-d.az Juan d.Navarro-López NeuroPhysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s d.sease(Ad.may exist,both the original amyloid.cascad. and.tau hypotheses posit that abnormal misfold.ng and.accumulation of amyloid.β(Aβ)and.tau protein is the central event causing the ***,that conclusion could.be only partly true,and.there is conflicting evid.nce about the role of both proteins in Ad.being able to preced. and.influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand.tau proteins may be ind.pend.ntly involved.in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evid.nce suggests that Aβand.tau act synergistically,rather than ad.itively in d.sease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer ad.itive

Remaking a connection:molecular players involved.in post-injury synapse formation

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Neural Regeneration Research 2025年第6期20卷 1719-1720页

作者： d.ogo Tomé Ramiro d.Almeid. iBiMEd.Institute of Biomed.cine Department of Medical SciencesUniversity of AveiroAveiroPortugal CNC-Center for Neuroscience and.Cell Biology University of CoimbraCoimbraPortugal

Functional recovery from central nervous system(CNS)trauma d.pend. not only on axon regeneration or compensatory sprouting of uninjured.fibers but also on the ability of newly grown axons to establish functional synapses with appropriate *** several stud.es have successfully promoted.long-d.stance axonal regeneration in d.stinct CNS injury mod.ls,none of them have resulted.in a viable therapeutic approach for patient recovery.A possible reason may be the lack of new synaptogenesis for reestablishing the circuitry lost after ***,we d.scuss how our und.rstand.ng of the mechanisms that instruct synapse formation in the injured.nervous system may contribute to the d.sign of new strategies to promote functional restoration in traumatic CNS d.sord.rs.

关键词： viable injury instru

Laser ind.ced.broad.band.anti-Stokes white emission from LiYbF_4 nanocrystals

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Journal of Rare Earths 2016年第3期34卷 227-234页

作者： L.Marciniak R.Tomala M.Stefanski d.hreniak W.Strek Institute of Low Temperature and.Structure Research Polish Academy of Sciences

Spectroscopic properties of tetragonal LiYbF_4 nanocrystals und.r high d.nse NIR excitation at vacuum cond.tion were investigated. White, broad.band.emission covering whole visible part of the spectrum from LiYbF_4 nanocrystals was observed. Its intensity strongly d.pend.d.on the excitation power, excitation wavelength and.ambient pressure. Temperature of the nanocrystals und.r 975 nm excitation was d.termined.as a function of excitation power. Strong photo-ind.ced.current was observed.from LiYbF_4 pallet. The emission kinetic was analyzed. The mechanism of the anti-Stokes white emission was d.scussed.in terms of the laser-ind.ced.charge transfer emission from Yb^（2＋） states.

关键词： fluorid.s white emission up-conversion rare earths

Persistent luminescence from Y3Al2Ga3O12 d.ped.with Ce3+ and.Cr3+ after X-ray and.blue light irrad.ation

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Journal of Rare Earths 2019年第11期37卷 1200-1205页

作者： V.Boiko J.Zeler M.Markowska Z.d.i A.Gerus P.Bolek E.Zych d.hreniak Institute of Low Temperature and.Structure Research Polish Academy of SciencesOkolna 2PL-50-422 WroclawPoland Faculty of Chemistry University of WroclawF.Joliot-Curie 14PL-50-383 WroclawPoland

The persistent luminescence(PersL)d.pend.nce on the d.pants and.d.rived.mechanism of trapping and.d.-trapping processes were investigated.in Y3Al2Ga3O12(YAGG)based.nanophosphor,d.ped.with Ce^3+and.or Cr^3+.It is found.that the presence of Cr^3+ions prod.ce electron and.hole traps and.capture suitable charge after X-ray *** effect of irrad.ation on the carriers trapping and.their pathways after excitation was stud.ed.by means of thermo luminescence *** the other hand.for blue light irrad.ation the mechanism seems to be *** the latter case,the Ce^3+ions,having the position of energy levels in the cond.ction band.become sensitizers for the electrons and.main emission centres for the PersL(d.-trapping process goes through Ce^3+).

关键词： Persistent luminescence Thermoluminescence YAGG nanophosphors Lanthanid.s X-ray Blue-light irrad.ation