Encontrados 80 documentos, a visualizar página 1 de 8
Tribological properties of antimicrobial surfaces for orthopaedics and oral reh...
Veloso, J.; Borges, J.; Vaz, F.; Carvalho, O.; Souza, J. C. M.; Gomes, J. R.Inflammatory reactions around implants and prosthetics can occur due to the accumulation of pathogenic bacteria species. The long-term success of implants and prostheses depends on the healthy state of surrounding mucosa, bone, and connective tissues, that can be controlled by manufacturing surfaces with specific physical-chemical aspects to prevent the accumulation of bacteria. Among several properties, the fr...
Conventional and recent advances of vegetable oils as Metalworking Fluids (MWFs...
Afonso, Inês S.; Nobrega, Glauco; Lima, Rui Alberto Madeira Macedo; Gomes, J. R.; Ribeiro, João E.Vegetable oils have been used as metalworking fluids (MWFs) for many years, particularly in small-scale metalworking operations and in industries where environmental regulations are strict. Before the development of modern MWFs, vegetable oils were one of the most common lubricants used for metalworking tools. The use of vegetable oils can be traced back to ancient civilizations such as Egypt, Greece, and Rome,...
Wear behavior of a new composite formulation, with TEOS addition, for abrasive ...
Capela, Paulina Araújo; Costa, Sharlane Maria; Souza, M. S.; Carvalho, Sérgio Manuel Freitas; Pereira, Mário; Carvalho, L.; Gomes, J. R.; Soares, DelfimVitrified grinding wheels are used in many manufacturing industries to shape and finish metals and other materials in an efficient way. This work addresses a new approach with the use of tetraethyl orthosilicate solution (TEOS solution or silica sol), as an additive, in vitrified abrasive composites for grinding wheels. Different types of composite were produced using always the same materials and processing me...
Comparative toothbrush abrasion resistance and surface analysis of different de...
Pinto, P.; Carvalho, A.; Silva, Filipe Samuel; Gomes, J. R.; Carvalho, Óscar Samuel Novais; Madeira, Sara Cristina SoaresDifferent materials have been used for dental restorations, and, like a natural tooth, they are subject to wear due to abrasion produced by toothbrushing during oral hygiene routine. The purpose of the present study was to evaluate the toothbrush abrasion resistance of four restorative dental CAD/CAM materials available on the market: an acrylic polymer -PMMA (DD TempMED HI, Dental Direkt), a composite resin (B...
Effect of grooves and their geometry on the wear behavior of structured grindin...
Capela, Paulina Araújo; Costa, Sharlane Maria; Souza, M. S.; Carvalho, Sérgio Manuel Freitas; Carvalho, L.; Pereira, M.; Gomes, J. R.; Soares, DelfimThe dry and wet wear behavior of different structured abrasive grinding wheels, with different grooves geometry, were investigated and compared with an unstructured abrasive composite. It was found that the grooves, as well as their geometry, play a decisive role in the wear behavior of abrasive composites.; This work is within the scope of the Sharlane Costa Ph.D. degree in progress, financially supported by t...
Rheology and soft tribology characterization of yoghurt with curcumin-loaded so...
Gonçalves R. F. S.; Abreu C. S.; Gomes, J. R.; Vicente, A. A.; Pinheiro, A. C.; Vieira, J. M.Consistency and mouthfeel arising from the consumption of yoghurts are crucial factors for the consumers’ acceptability. The aim of this work was to identify potential differences in sensory perceptions of yoghurts with curcumin-loaded solid lipid nanoparticles (SLN) incorporation. Rheology coupled with tribology were considered to simulate the dynamic aspects of oral processing. The friction behaviour showed s...
Dynamic aspects of oral processing of curcumin-loaded solid lipid nanoparticles...
Gonçalves, Raquel Filipa Silva; Abreu, C. S.; Gomes, J. R.; Vicente, A. A.; Pinheiro, A. C.; Vieira J. M.Mouthfeel and consistency originating from the consumption of yoghurts represent decisive factors for the consumers’ acceptability. The present work aims to identify potential differences in the sensory perceptions of yoghurts with curcumin-loaded solid lipid nanoparticles (SLN) incorporation. Thus, rheology coupled with tribology were considered to simulate the dynamic aspects of oral processing. Similar value...
Effect of carbon nanotubes on the biotribological behavior of hotpressed PEEK-b...
Pigosso, T.; Richhariya, Vipin; Binder, C.; Silva, Filipe Samuel; Carvalho, Óscar Samuel Novais; Gomes, J. R.This study aims to evaluate the influence of carbon nanotubes (CNTs) content (0.1, 0.5, 1, and, 5 wt%) on the poly-ether-ether-ketone (PEEK) composites based on a veneering concept and produced by the hot-pressing technique. Biotribological tests were performed in a ball-on-plate geometry using an alumina ball as the counter body under a phosphate-buffered saline solution at 37 degrees C, assessing the coeffici...
Effect of distance between grooves on the wear of structured grinding wheels
Costa, Sharlane Maria; Capela, Paulina Araújo; Souza, Maria Sabrina Veira Miranda Palva; Carvalho, Sérgio Manuel Freitas; Pereira, Mário; Carvalho L.During roughing and surface finishing operations a lot of heat is generated in the grinding wheel/workpiece contact zone. The surface structuring/texturing of abrasive wheels has been a proposal to reduce the operating temperature. In this work, three spiral grooved abrasive discs were produced, with different distances between grooves. The wear behavior of structured grinding wheels was evaluated by lubricated...
Wear behavior of dental glass-ceramics: a scoping review on the damage of oppos...
Souza, Júlio C. M.; Silva, Cristina S.; Caramês, João; Henriques, Bruno; Oliveira, António P. Novaes de; Silva, Filipe Samuel; Gomes, J. R.The main aim of this study was to perform a scoping review on the wear behaviour of recent dental glassceramics and its influence on the damage of opposing tooth enamel surfaces. Relevant in vivo and in vitro studies reported significant damage on enamel surfaces after friction against current glass-ceramics and therefore different parameters have been studied such as the glass-ceramic type, wear set up, enviro...