Publications by authors named "Dolores R R Lazar"

In this study, we present a novel approach for the exfoliation of titanium nitride (TiN) powders utilizing a rapid, facile, and environmentally friendly non-thermal plasma method. This method involves the use of an electric arc and nitrogen as the ambient gas at room temperature to generate ionized particles. These ionized species interact with the ceramic crystal of TiN, resulting in a pronounced structural expansion.

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Objectives: This study aimed to evaluate the effect of microwave sintering temperature and cooling rate (MS) on 3Y-TZP ceramics and its influence on the ceramic microstructure and mechanical properties. Specifically, to optimize the sintering process, reducing the total sintering time compared to conventional sintering.

Materials And Methods: Eighty-four pre-sintered Y-TZP discs (Vipi block Zirconn, VIPI) (ISO 6872) were divided into seven groups (n = 12) according to the sintering conditions: conventional sintering (CS) at 1530 °C for 120 min and microwave sintering at 1400 °C (MS1400) and 1450 °C (MS1450) for 15 min followed by different cooling conditions: rapid cooling (RC), cooling at 400 °C (C400) and 25 °C (C25).

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Y-TZP/MWCNT-SiO nanocomposite was synthesized by co-precipitation and hydrothermal treatment methods. After the characterization of the MWCNT-SiO powder, specimens were obtained from the synthesized material Y-TZP/MWCNT-SiO by uniaxial pressing for a second characterization and later comparison of its optical and mechanical properties with the conventional Y-TZP. The MWCNT-SiO was presented in bundles of carbon nanotubes coated by silica (mean length: 5.

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The aim of this study was to synthesize hydroxyapatite (HAP) powder from fish waste. The powder was characterized through X-ray diffraction, Fourier transform infrared spectroscopy, ion exchange chromatography, scanning electron microscopy and plasma emission spectrometry. The cyto- and genotoxicity was carried out to demonstrate biocompatibility in vivo by means of rat subcutaneous tissue test.

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Objective: To investigate the effect of titania addition (0, 10 and 30mol%) on the microstructure, relative density, Young's modulus (E), Poisson's ratio (υ), mechanical properties (flexural strength, σ, and Weibull modulus, m) of a Y-TZP/TiO composite. The effect of the presence of a biomimetic coating on the microstructure and mechanical properties was also evaluated.

Methods: Y-TZP (3mol% of yttria) and Y-TZP/TiO composite (10 or 30mol% of titania) were synthesized by co-precipitation.

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Objectives: To investigate the crystalline phases, morphological features and functional groups on the surface of sintered Y:TZP/TiO2 composite ceramics before and after the application of a biomimetic bone-like apatite layer. The effect of TiO2 content on the composite's characteristics was also evaluated.

Methods: Samples of Y:TZP containing 0-30mol% TiO2 were synthesized by co-precipitation, followed by filtration, drying and calcination.

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Objectives: (1) To synthesize 3mol% yttria-stabilized zirconia (3Y-TZP) powders via coprecipitation route, (2) to obtain zirconia ceramic specimens, analyze surface characteristics, and mechanical properties, and (3) to compare the processed material with three reinforced dental ceramics.

Methods: A coprecipitation route was used to synthesize a 3mol% yttria-stabilized zirconia ceramic processed by uniaxial compaction and pressureless sintering. Commercially available alumina or alumina/zirconia ceramics, namely Procera AllCeram (PA), In-Ceram Zirconia Block (CAZ) and In-Ceram Zirconia (IZ) were chosen for comparison.

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