This work involved the synthesis and characterization of Cu0.5Zn0.5Fe2O4ferrite powders prepared by combustion reaction for use as soft magnetic materials. The powders were characterized by nitrogen adsorption (BET), XRD, Rietveld refinement, SEM, TEM and magnetic measures. The results indicate that the combustion reaction yielded crystalline powders containing spinel ferrite as the primary phase and traces of Fe2O3as secondary phase. The crystallite size and lattice microdeformation calculated from Rietveld refinements were 36 and 0.24 nm, respectively. The micrographic analysis revealed particles smaller than 100 nm and fine particle agglomerates. The particles were approximately spherical and their size, calculated by TEM, was 29 nm. The magnetic parameters indicated that the Cu-Zn ferrite powders presented closed hysteresis loops and soft magnetic properties.

This work aims to conduct a study of development and characterization of a new endodontic biociment, the MTA/HAp. To this was used MTA Angelus ® and a HAp synthesized in the laboratory in the proportions by weight 99% MTA/1% HAp (BIOC 1) and 95% MTA/5% HAp (BIOC 5), where the hydroxyapatite was added in order to introduce MTA to the characteristic of osteoconduction. The tests for the characterization of new cement were: X-ray diffraction, scanning electron microscopy and radiographic appearance. The results showed that the new developed biociments were obtained efficiently, since they showed the same crystalline phases of its starting materials (mineral trioxide aggregate and hydroxyapatite), with a morphology consisting of agglomerates of homogeneous distribution of irregular size and shape particles pre-sintered spherical and radiopacity feasible to be used in endodontics.Keywords:biomaterial,sealer,mineraltrioxideaggregate,hydroxyapatite.

The aim of this work is to prepare and characterize Al2O3-ZrO2 powders by Pechine method and to evaluate them as supports for palladium catalysts in the selective reduction of NO with CH4. The effect of aluminum ion on the final characteristics of the zirconia powder is also investigated. The catalytic supports were characterized by X-ray diffraction (XDR), scanning electron microscopy (SEM) and catalytic activity. The XRD data showed the formation of tetragonal zirconia phase, with crystallite size of 6.3 and 6.1 nm for the supports prepared with 0.1 and 0.5 moles of Al3+, respectively. Both supports showed porous and homogeneous agglomerates. Pd/Al2O3-ZrO2 catalysts were active NO reduction by CH4.