57 documents found, page 1 of 6
Alumina applied in bone regeneration: Porous α-alumina and transition alumina
Silva,J. R. S.; Santos,L. N. R. M.; Farias,R. M. C.; Sousa,B. V.; Neves,G. A.; Menezes,R. R.Abstract Alumina is a polymorphic bioceramic that has been extensively investigated for application in bone regeneration. Dense α-alumina has been considered a suitable biomaterial for dental and orthopedic implants due to its superior mechanical properties. However, its use is limited due to its high inertia in a biological environment. Recent investigations have focused on its distinct phases and surface char...
Freeze-casting applied to ceramic materials: a short review of the influence of...
Santos,L. N. R. M.; Silva,J. R. S.; Cartaxo,J. M.; Rodrigues,A. M.; Neves,G. A.; Menezes,R. R.Abstract In recent years there is a high interest in the freeze-casting process because it is a simple, economical, and environmentally friendly method for obtaining highly porous materials. Most of the materials obtained by this technique have directional pore structure and anisotropic properties. However, a wide range of pore size and morphology can be obtained by the control of processing parameters, such as...
Use of nanostructured and modified TiO2 as a gas sensing agent
Alves Junior,R.; Alves,H. P. A.; Cartaxo,J. M.; Rodrigues,A. M.; Neves,G. A.; Menezes,R. R.Abstract Titanium dioxide (TiO2) has attracted interest for sensory applications due to its high surface area and the high density of active adsorption sites. This review shows the effect of the nanostructure, synthesis technique, operating temperature, target gas, and the impact of incorporating metallic elements on the detection properties of TiO2. The studies showed that the TiO2 gas detection process is clo...
Influence of MgO and CaCl2 on the rheological properties of bentonitic clays fr...
Buriti,B. M. A. B.; Araújo,M. E. B.; Bastos,P. M.; Cartaxo,J. M.; Neves,G. A.; Ferreira,H. S.Abstract New deposits of bentonite clays have been discovered in the Brazilian State of Paraíba; the most recent was at the municipality of Olivedos. Recent studies have discovered the presence of high levels of non-clay minerals that can produce unsatisfactory results when attempting to use these clays in drilling fluids. In order to make them suitable for this purpose, the MgO and CaCl2 as chemical additives ...
Influence of the additivation process on cation exchange capacity and viscosity...
Morais,I. C. G.; Silva,I. A.; Buriti,B. M. A. B.; Fernandes,J. V.; Silva,D. S.; Neves,G. A.; Ferreira,H. S.Abstract In Brazil, bentonite clays are not naturally sodic and it is an industrial practice the sodium additivation, since sodium ion expands their lamellae allowing a larger amount of water to penetrate. The objective was to analyze the influences of the use of sodium carbonate on the clay during the additivation process, the moisture content and the cure time on cation exchange and viscosity of bentonite cla...
Nanostructured titanium dioxide for use in bone implants: a short review
Neta,I. A. Bezerra; Mota,M. F.; Lira,H. L.; Neves,G. A.; Menezes,R. R.Abstract Titanium dioxide (TiO2) based nanostructured materials have shown great potential for use in implants thanks to their excellent physicochemical properties, such as high specific surface area, ability to elicit positive cell response, and stability in body fluids. However, there are few studies in the literature that focus on the use of nanostructured TiO2 to support cell growth and bone regeneration. T...
CaFe2O4 ferrite nanofibers via solution blow spinning (SBS)
Araujo,R. N.; Nascimento,E. P.; Sales,H. B.; Silva,M. R.; Neves,G. A.; Menezes,R. R.Abstract CaFe2O4 nanofibers were successfully synthesized via solution blow spinning (SBS), and the influences of heat-treatment on morphological, microstructural, magnetic, and optical properties of the nanofibers were evaluated. In the synthesis process, stoichiometric amounts of iron and calcium nitrates were dissolved in an aqueous solution containing polyvinylpyrrolidone (PVP) and, after that, hybrid nanof...
Uso de diopsídio em massas cerâmicas para grés sanitários
Silva,R. H. L.; Neves,G. A.; Ferreira,H. C.; Santana,L. N. L.; Nóbrega,A. C. V.; Menezes,R. R.Resumo Atualmente, há uma severa escassez de jazimentos de feldspato de boa qualidade. Por outro lado, o diopsídio vem se mostrando um fundente alternativo para a indústria cerâmica, mas ainda pouco estudado. Assim, este trabalho avaliou o efeito da substituição parcial do feldspato pelo diopsídio em formulações para grés sanitário. Substituiu-se de 2 a 20% da massa total de feldspato por diopsídio. As matérias...
Characterization of clays from the State of Paraíba, Brazil for aesthetic and m...
Buriti,B. M. A. B.; Buriti,J. S.; Silva,I. A.; Cartaxo,J. M.; Neves,G. A.; Ferreira,H. C.Abstract This study aimed to evaluate the potential of clays from the State of Paraíba to be used for medicinal, therapeutic and aesthetic treatments. The samples were characterized by X-ray diffraction, X-ray fluorescence chemical composition, thermogravimetry, differential thermal analysis, laser diffraction granulometric analysis, cation exchange capacity, and antimicrobial activity. Based on the study, it w...
Cinza de biomassa rica em calcário como material carbonático em sistemas ciment...
Nascimento,J. E. F.; Nóbrega,A. C. V.; Ferreira,H. C.; Neves,G. A.; Santana,L. N. L.Resumo O uso de materiais alternativos, em substituição ao clínquer, tem sido amplamente estudado, a fim de reduzir custos e minimizar os danos ambientais causados pela produção do cimento Portland. Investigou-se a influência do uso da cinza de algaroba (Prosopis juliflora), material rico em carbonato de cálcio, nos mecanismos de hidratação e formação das principais fases hidratadas do cimento Portland. As cara...