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Artigo IPEN-doc 20314 Strontium and cobalt doped-lanthanum chromite2015 - 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.Resumo IPEN-doc 17968 Rheological study of doped lanthanum chromite aqueous suspension2011 - SETZ, L.F.G.; SANTACRUZ, I.; COLOMER, M.T.; MORENO, R.; MELLO CASTANHO, S.R.H.Resumo IPEN-doc 13348 Comportamento reologico de suspensoes aquosas de cromito de lantanio - colagem em moldes de gesso (slip casting)2008 - SETZ, L.F.G.; SANTACRUZ, I.; COLOMER, M.T.; MORENO, R.; MELLO CASTANHO, S.R.H.Resumo IPEN-doc 13309 Analise reologica de suspensoes aquosas de cromito de lantanio2008 - SETZ, L.F.G.; SANTACRUZ, I.; COLOMER, M.T.; MORENO, R.; MELLO CASTANHO, S.R.H.Artigo IPEN-doc 14248 Processamento e conformacao de fitas (tape casting) a partir de suspensoes coloidais de cromito de lantanio sintetizado por reacao de combustao2009 - SETZ, L.F.G.; MELLO CASTANHO, S.R.H.; SANTACRUZ, I.; COLOMER, M.T.; MORENO, R.Artigo IPEN-doc 13766 Surface behaviour and stability of strontium and cobalt doped-lanthanum chromite powders in water2009 - SETZ, LUIZ F.G.; MELLO CASTANHO, SONIA R.H. de; COLOMER, MARIA T.; MORENO, RODRIGOArtigo IPEN-doc 14266 Physicochemical characterization of strontium and cobalt-doped lanthanum chromite powders produced by combustion synthesis2009 - SETZ, LUIZ F.G.; MELLO CASTANHO, SONIA R.H.; MORENO, RODRIGO; COLOMER, MARIA T.Artigo IPEN-doc 14935 Tape casting of strontium and cobalt doped lanthanum chromite suspensions2010 - SETZ, LUIZ F.G.; SANTACRUZ, ISABEL; COLOMER, M.T.; MELLO CASTANHO, SONIA R.H.; MORENO, RODRIGOArtigo IPEN-doc 17675 Fabrication of Sr- and Co-doped lanthanum chromite interconnectors for SOFC2011 - SETZ, L.F.G.; SANTACRUZ, I.; COLOMER, M.T.; MELLO CASTANHO, S.R.H.; MORENO, R.Artigo IPEN-doc 17855 Comportamento reológico de suspensões aquosas de cromito de lantânio2011 - SETZ, L.F.G.; SANTACRUZ, I.; COLOMER, M.T.; MORENO, R.; MELLO CASTANHO, S.R.H.