Resolução de sobreposição de picos de cristalização, pelo método de Kurajica, caso não isotérmico, em vidros teluretos e fosfatos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização de sistemas vítreos baseados no formador B2O3 e P2O5 dopados com CeO2

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento de revestimentos híbridos do sistema siloxano-PMMA com aplicações anticorrosivas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Síntese e caracterização da cerâmica 'Ti IND. x''('Sm IND. 0,2''Ce IND. 0,8') IND. (1-x)''O IND. (2-Б) para aplicação como anodo em células a combustível de óxido sólido

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análises estrutural, nanoestrutural, e quantitativa de fases em materiais cerâmicos de interesse tecnológico, utilizando difração de raios X pelo método do pó

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo dos difenilfosfinatos de lantânio ativados por cério, európio e térbio emissores luminescentes multicores

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Preparação e estudo termoanalítico dos 4-Clorobenzalpiruvatos de lantanídeos (III) e de ítrio (III) no estado sólido

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Síntese, caracterização e estudo termoanalítico dos 2-metoxibenzalpiruvatos de lantanídios (III), exceto promécio, e de ítrio (III) do estado sólido

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Complexos de lantanídeos contendo ligantes organofosforados como matrizes para materiais luminescentes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Thermal investigation and infrared evolved gas analysis of solid trivalent lanthanide and yttrium alpha-hydroxyisobutyrates in N-2 and CO2 atmospheres

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Síntese e propriedades fotoluminescentes do óxido de cério dopado com magnésio

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Propriedades estruturais e espectroscópicas de complexos de difenilfosfinatos dos sistemas ternários 'LA'-'CE'-'EU'/'LA'-CE'-'TB'

Pós-graduação em Química - IQ

Sr2CeO4: Electronic and structural properties

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo termoanalítico de complexos do fármaco Ibuprofeno com lantanídeos (III) leves no estado sólido com exceção do promécio

This Final Paper had as it main goal to make a thermoanalytical study of lighter trivalent lanthanides (Lanthanum, Cerium, Praseodymium, Neodymium, Samarium and Europium) with the Ibuprofen ligand (nonsteroidal anti-inflammatory) that have a general formula LnL3.nH2O, on solid state, where Ln are the Lanthanides, L is the Ibuprofen ligand and n = number of water molecules of hydration that went from 1,0 to all the compounds. In order to characterize this compounds, it has been used the thermoanalytical techniques TG-DTA (thermogravimetry - Diferential Thermal Analysis) and DSC (Diferential Scanning Calorimetry), Fourier transformed infrared spectroscopy (FTIR) and complexometric titration with EDTA. Through the TG-DTA technique, it has been possible to set the thermal stability of the compounds, the number of thermal decomposition steps and temperatures that ocurred that also provided stoichiometry to the synthesized compounds. The DSC technique has shown the enthalpy of dehydration of the samarium and europium compounds, it was not possible to see it in the other compounds due to a endothermic peak on the DSC curve not being formed. In the case of neodymium, a thermal event ocurred, in which it could be a oxidative decarboxylation right after the dehydration. The infrared was utilised to study the carboxilate groups streches, and so, suggest a ligand metals compound coordination, that to this present paper has been a bidentade bridged coordenation. At last, the complexometric tritation was used to very the ammount of metal present in each compound, and so, verify if the proposed stoichiometry was according to the theory

Caracterização de cerâmicas a base de nitreto de silício para aplicações estruturais

The need for development of new materials is a natural process in the companies’ technological point of view, seeking improvements in materials and processes. Specifically, among the materials, ceramic exhibit valuable properties, especially the covalent ceramics which have excellent properties for applications which requires the abrasion resistance, hardness, high temperatures, resistence, etc. being a material that has applications in several areas. Most studies are related to improvement of properties, specially fracture toughness that allows the expansion of its application. Among the most promising ceramic materials are silicon nitride (Si3N4) which has excellent properties. The goal of this work was the development and caracterization of Si3N4-based ceramics, doped with yttrium oxide (Y2O3), rar earth concentrate (CTR2O3) and cerium oxide (CeO2) in the same proportion for the evaluation of properties. The powders' mixtures were homogenized, dried and compressed under pressure uniaxial and isostatic. Sintering was carried out in 1850 ⁰C under pressure of 0,1MPa N2 for 1 h with a heating rate of 25 ⁰C / min and cooling in the furnace inertia. The characterizations were performed using Archimedes principle to relative density, weight loss by measuring before and after sintering, phase analysis by X-ray diffraction, microstructure by scanning electron microscope (SEM), hardness and fracture toughness by the method Vickers indentation. The results obtained showed relative density of 97-98%, Vickers hardness 17 to 19 GPa, fracture toughness 5.6 to 6.8 MPa.m1/2, with phases varying from α-SiAlON and β-Si3N4 depending the types of additives used. The results are promising for tribological applications and can be defined according to the types of additives to be used