SONIA REGINA HOMEM DE MELLO CASTANHO

SONIA REGINA HOMEM DE MELLO CASTANHO

(Fonte: Lattes)

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Graduada em Engenharia de Materiais (UFSCar, Universidade Federal de São Carlos), Mestre em Tecnologia Nuclear (IPEN/USP, Universidade de São Paulo) e Doutora em Ciências Químicas-Cerâmicos (UAM/ES -ICV/CSIC, Universidad Autónoma de Madrid, Espanha e Instituto de Ceramica y Vidrio/CSIC de Espanha). Ela é Pesquisadora Senior e atualmente Gestora Adjunta em Pesquisa e Desenvolvimento do Centro de Ciências e Tecnologia de Materiais (CCTM) do Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP). É Professora da Universidade de São Paulo (USP), no programa de posgraduação Tecnologia Nuclear - Materiais. Coordenadora do grupo de pesquisas (GP/CNPq) em Materiais e Meio Ambiente. Principais áreas de atuação: - Energias Renováveis (células a combustível, catalizadores e biomassa), - Ambiental (mitigação, inertização e requalificação de efluentes e subprodutos de processos extrativistas e industriais, diretivas ambientais (RhOS, WEEE)), - Cerâmicas Biocompatíveis (vidros, compósitos multifuncionais para a implantologia). Experiência em gestão de Centro de Pesquisas, gestão ambiental, gestão de projetos, planejamento composicional de materiais, processamento coloidal, reologia, vidros e vitroceramicos, compósitos multifuncionais e nanoestruturas naturais. (Texto extraído do Currículo Lattes em 27 dez. 2021)

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Processing, microstructure and thermoluminescence response of biomorphic yttrium oxide ceramics
2016 - SANTOS, S.C.; YAMAGATA, C.; CAMPOS, L.L.; MELLO-CASTANHO, S.R.H.
The present work reports a fast-direct bio-prototyping process using Luffa Cylindrica vegetable sponge to produce biomorphic yttrium oxide ceramics with reticulated-porous architecture and thermoluminescence response. Processing parameters as rheology of yttrium oxide suspensions, bio-template surface treatment and thermal decomposition of bio-template were investigated. Shear thinning suspensions of 30 vol% yttrium oxide with apparent viscosity of 243mPa.s provided a successful impregnation of samples, whereby bio-templates with smooth ceramic layer and hierarchical reticulated architecture were formed. By thermal treatment at 1600 degrees C for 2 h biomorphic yttrium oxide ceramics with porous microstructure and TL response at 150 degrees C and lambda=550 nm were produced. The proposed fast direct bio-prototyping process is suitable for the production of ceramic components with complex shape and demonstrates potential for general applicability to any bio-template. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
Strontium and cobalt doped-lanthanum chromite
2015 - SETZ, L.F.G.; SANTACRUZ, I.; LEON-REINA, L.; TORRE, A.G. De la; ARANDA, M.A.G.; MELLO CASTANHO, S.R.H.; MORENO, R.; COLOMER, M.T.
Perovskite powders prepared by combustion synthesis with a nominal composition of La0.800Sr0.200Cr0.920Co0.080O3.000 δ were obtained from the corresponding metal nitrates, and characterised in terms of in-situ phase development (crystalline structure and thermal behaviour). Synchrotron X-ray powder diffraction (SXRPD) and Rietveld analyses demonstrated that the as-prepared powder showed an orthorhombic perovskite structure with an estimated composition of La0.803Sr0.197Cr0.966Co0.034O3.000 δ. Second phases present in the as-prepared powder were m-LaCrO4, CoLa1.250Sr0.750O4.000, c-CoCr2.000O4.000 and m-SrCrO4.000. Sintering processes, including phase transition (from orthorhombic to rhombohedral) of the main phase and, melting/evaporation of second phases have been studied by DTA/TGA and dilatometric studies; the results were in full agreement with those detected by High-Temperature Synchrotron X-ray powder diffraction (HT-SXRPD). The transition temperature was determined to be 1380 1C by dilatometric studies, and between 1240 and 1405 1C by HT-SXRPD. Dye-pressed samples sintered at 1600 1C/4 h showed a density of 98.9 dth%. The phase transition is an irreversible process since the sintered perovskite, measured at room temperature after cooling, only showed the rhombohedral phase as main phase. The evaluation of the linearity of the conductivity versus the inverse of temperature and the activation energy values of the sintered material indicated that the electrical conduction occurs via the non-adiabatic small-polaron mechanism in either air or hydrogen atmosphere. In the reducing environment, the perovskite shows significantly reduced electrical conductivity compared with that in air, as it is expected for a p-type conductor. & 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.