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Journal of Advanced Ceramics 2016年第2期5卷 103-110页

作者： Y.F.GOmES A.K.FrEITAS r.m.NASCImENTO m.r.d.bomio C.A.PASKOCImAS F.V.mOTTA departamento de Engenharia de materiais Universidade Federal do Rio Grande do Norte 59078-900 Natal/RN Av.Sen.Salgado Filho 3000 CEP 59072-970 Brazil

In this study, the nanostructures of pure ZnO and ZnO:xCe3+ were prepared using statistic design—factorial design 3(3?1)?3-level and mixed-level factorials and fractional with replicates in the central point, totaling 11 experiments. The experiments were performed using the microwave-assisted hydrothermal (mAH) method with Ce3+ concentration of 2 and 4 mol% at 60, 110, and 160 °C for 10, 20, and 30 min. X-ray diffraction (Xrd), scanning electron microscopy (SEm), and optical diffuse reflectance were used to characterize the products. The fractional factorial design indicated the optimal design area, and the studies were continued by ridge analysis. The analysis of variance (ANOVA), the Pareto, and the model adjusted to the conditions proposed in this study due to the determination coefficient of 99.9%, variance (r 2), and response surface generated were satisfactory, thus having an optimization in the process of obtaining ZnO doped with Ce.

关键词： hydrothermal ZnO cerium photocatalytic activity factorial design 3(3-1)

red-emitting CaWO4:Eu^(3+),Tm^(3+)phosphor for solid-state lighting:Luminescent properties and morphology evolution

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Journal of rare Earths 2022年第2期40卷 226-233,I0002页

作者： L.X.Lovisa I.m.P.da Silva A.A.G.Santiago m.Siu Li E.Longo C.A.Paskocimas m.r.d.bomio F.V.motta Institute of Physics and Chemistry.Federal University of Itajubd(UNIFEI) ItajubdMG37500-903Brazil LSQm-Laboratory of Chemical Synthesis of materials-department of materials Engineering Federal University of Rio Grande Do NorteP.O.Box 152459078-900Natal RNBrazil IFSC USPAv.Trabalhador Sao Carlense400CEP 13566-590Sao CarlosSPBrazil CdmF-LIEC UFSCarP.O.Box 67613565-905Sao Carlos.SPBrazil

CaWO_(4):xEu^(3+),yTm^(3+)crystals were obtained by facile synthesis at low temperature by the microwaveassisted hydrothermal method(mAH).The phase formation,morphology,luminescent properties and ene rgy transfer were *** X-ray diffraction(Xrd)re sults show the formation of a scheelitelike tetragonal structure without the presence of secondary *** growth mechanism of hierarchical micro structures based on self-assembly and Ostwald-ripening processes was evaluated,obtaining different types of *** luminescence spectra of CaWO_(4):Eu^(3+),Tm^(3+)at 325 nm excitation show the predominance of red emission at the 5 d0→7 F2(Eu^(3+))transition at 624 *** feature signals dominant behavior of the electric dipole *** presence of Tm^(3+)is notably evident in the absorption spectra by the related excitation transitions:3 H6→1 G4,3 H6→3 F3 and 3 H6→3 *** parameters are discussed to characterize CaWO_(4):Eu^(3+),Tm^(3+)*** study of the emission spectrum as a function of the concentration of Eu^(3+)(x mol%)and Tm^(3+)(y mol%)indicates that the CaWO_(4):Eu^(3+),Tm^(3+)phosphors show stronger red emission intensity and exhibit the CIE value of x=0.63 and y=*** photoluminescence results show 97%high color purity for CaWO_(4):4 mol%Eu^(3+),a high CrI(92%)and a low CCT of 1085 *** results demonstrate that the CaWO_(4):Eu^(3+),Tm^(3+)red phosphors are promising as color converters for application in white light-emitting diodes and display devices.

关键词： CaWO_(4):Eu^(3+),Tm^(3+)microwave-assisted hydrothermal method Photoluminescence red phosphor rare earths

Influence of variables on the synthesis of CoFe_(2)O_(4)pigment by the complex polymerization method

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Journal of Advanced Ceramics 2015年第2期4卷 135-141页

作者： P.N.mEdEIrOS Y.F.GOmES m.r.d.bomio I.m.G.SANTOS m.r.S.SILVA C.A.PASKOCImAS m.S.LI F.V.mOTTA department of materials Engineering Federal University of Rio Grande do NorteCampus Lagoa NovaCEP 59078-900-Natal/RNBrazil department of Chemistry Federal University of ParaíbaCidade UniversitáriaCEP 58051-900-João Pessoa/PBBrazi Institute Physics of São Carlos USPCEP 13566-590São CarlosSão PauloBrazil

Synthetic inorganic pigments are most widely used in ceramic applications due to their excellent chemical and thermal stability and their lower toxicity to both human and environment as *** the present work,black ceramic pigment CoFe_(2)O_(4)has been synthesized by the complex polymerization method(CPm)with good chemical *** order to study the influence of variables on the process of obtaining pigment through CPm,2^((5-2))fractional factorial design with resolution III was *** variables studied in the mathematical modeling were:citric acid/metal concentration,pre-calcination time,calcination temperature,calcination time,and calcination *** pigments were characterized by X-ray diffraction(Xrd),scanning electron microscopy(SEm),and UV-visible(UV-Vis)*** on the results,the formation of cobalt ferrite phase(CoFe_(2)O_(4))with spinel structure was *** color of pigments obtained showed dark shades,from black to *** model adjusted to the conditions proposed in this study due to the determination coefficient of 99.9%and variance(r²)showed that all factors are significant at the confidence level of 95%.

关键词： pigment complex polymerization method(CPm) fractional factorial design

Effect of different starting materials on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)

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Journal of Advanced Ceramics 2015年第1期4卷 65-70页

作者： P.N.mEdEIrOS V.d.ArAÚJO A.P.A.mArQUES r.L.TrANQUILIN C.A.PASKOCImAS m.r.d.bomio J.A.VArELA E.LONGO F.V.mOTTA dEmAT CTUFRNAv.Sen.Salgado Filho3000CEP 59072-970 NatalRNBrazil UACSA UFRPEBR 101 Sul5225CEP 54510-000 Cabo de Santo AgostinhoPEBrazil UNIFESP Rua Prof.Artur Riedel275CEP 09972-270 DiademaSPBrazil dLIECIQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazil LIEC IQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazi

Literature has reported the synthesis of barium calcium titanates by various synthesis methods such as solid state reaction,co-precipitation and polymer *** compounds are usually obtained using calcium carbonate(CaCO_(3)),barium carbonate(BaCO3)and titanium oxide as starting *** study investigated the effect of different starting reagents on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)(BCT)by complex polymerization method(CPm).Two sets of starting precursors were used:titanium citrate,CaCO_(3)and BaCO3,and titanium citrate and Ba1-xCaxCO3 solid solution *** were crystallized at a temperature range from 400℃to 700℃for different *** obtained powders were characterized by X-ray diffraction(Xrd),thermogravimetry(TG)and differential thermal analysis(dTA),and raman and infrared *** infrared spectroscopy indicated that the chelation processes of Ba,Ca,Ti and CA ions are very *** results showed that the use of CaCO_(3)and BaCO3 or Ba1-xCaxCO3 solid solution as precursors does not affect the final properties of BCT powders obtained by CPm.

关键词： ceramic synthesis Ba_(0.8)Ca_(0.2)TiO_(3)(BCT) complex polymerization method(CPm)

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAUrABH r.KIrAN d.SINGH r.VAISH V.S.CHAUHAN School of mechanical and materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSdT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEm), and an in-house code is developed in the mATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

关键词： finite element method (FEm) nonlinear Green-Lagrange inverse hyperbolic shear deformation theory (IHSdT) bio-inspired composite plate helicoidal O322

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural regeneration research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam m.r.Groh moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.r.Wayne moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by robertson and río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus rNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

Polyethylene glycol fusion repair of severed rat sciatic nerves reestablishes axonal continuity and reorganizes sensory terminal fields in the spinal cord

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Neural regeneration research 2025年第7期20卷 2095-2107页

作者： Emily A.Hibbard Liwen Zhou Cathy Z.Yang Karthik Venkudusamy Yessenia montoya Alexa Olivarez George d.Bittner dale r.Sengelaub Program in Neuroscience Indiana UniversityBloomingtonINUSA department of Neuroscience University of Texas at AustinAustinTXUSA

Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions;behavioral recovery is typically *** used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic *** have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration,and PEG-fused animals exhibit rapid(within 2–6 weeks)and extensive locomotor ***,our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific,i.e.,spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target *** this study,we examined the consequences of PEG-fusion for sensory axons of the sciatic *** adult male and female rats(Sprague–dawley)received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without(Negative Control)the application of *** action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury *** success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days *** 2–42 days postoperatively,we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish ***-fusion repair reestablished axonal *** to unoperated animals,labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn,as well as inappropriate mediolateral and rostrocaudal ***,despite having intact peripheral nerves,similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repa

关键词： axotomy dorsal horn peripheral nerve injury plasticity polyethylene glycol(PEG) sciatic nerve sensory terminals wheat germ agglutinin horseradish peroxidase

Coarse to Fine: The role of Severe Plastic deformation in Advancing Titanium-Based medical Implants - A Comprehensive review

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Journal of Wuhan University of Technology(materials Science) 2025年第1期40卷 295-306页

作者： dragana r mihajlović Bojan I međo Ivana Lj Cvijović-Alagić Veljko r djokić Faculty of Technology and metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča Institute of Nuclear Sci-ences-National Institute of the republic of Serbia University of Belgrade11001BeogradSerbia Innovation Centre of the Faculty of Technology and metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPd)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPd process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPd techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPd process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

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Neural regeneration research 2025年第4期20卷 1092-1093页

作者： danko Jeremic Lydia Jiménez-díaz 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 disease(Ad)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding 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 evidence about the role of both proteins in Ad,being able to precede 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 independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

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： diogo Tomé ramiro d.Almeida iBimEd-Institute of Biomedicine Department of Medical SciencesUniversity of AveiroAveiroPortugal CNC-Center for Neuroscience and Cell Biology University of CoimbraCoimbraPortugal

Functional recovery from central nervous system(CNS)trauma depends 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 studies have successfully promoted long-distance axonal regeneration in distinct CNS injury models,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 discuss how our understanding of the mechanisms that instruct synapse formation in the injured nervous system may contribute to the design of new strategies to promote functional restoration in traumatic CNS disorders.

关键词： viable injury instru