14 documents found, page 1 of 2
Structural, Morphological and Dielectric Characterization of BiFeO3 Fibers Grow...
Peixoto, Marina Vieira; Costa, Florinda Mendes; Devesa, Susana; Graça, Manuel Pedro FernandesBiFeO3 fibers were prepared by the Laser Floating Zone (LFZ) technique using different growth speeds. The structural characterization of the samples was undertaken using X-ray diffraction (XRD) and Raman spectroscopy, the morphological characterization by scanning electron microscopy (SEM), and the electrical characterization by impedance spectroscopy. The XRD patterns showed that BiFeO3 was the major phase in ...
Influence of Polymeric Blends on Bioceramics of Hydroxyapatite
Gomes, Eduardo da Silva; Lima, Antônia Millena de Oliveira; Gavinho, Sílvia Rodrigues; Graça, Manuel Pedro Fernandes; Devesa, SusanaBioceramics are used to repair, rebuild, and replace parts of the human body, e.g., bones, joints and teeth, in the form of powder, coatings or prostheses. The synthetic hydroxyapatite [Ca10(PO4)6(OH)2 (HAP)] based on calcium phosphate has been widely used in the medical and dental areas due to the chemical similarity with the inorganic component of human bone tissue. In this work, hydroxyapatite nanocrystallin...
Influence of the Particle Size on the Electrical, Magnetic and Biological Prope...
Regadas, Joana Soares; Gavinho, Sílvia Rodrigues; Teixeira, Sílvia Soreto; de Jesus, Juliana Vieira; Pádua, Ana Sofia; Silva, Jorge CarvalhoBioglasses have been used throughout the past century as a biomaterial in the bone regeneration field. However, recent studies have attempted to use them as a therapeutic material as well, mainly in the treatment of osteosarcomas. The most widely recognized bioglass is the 45S5 Bioglass, invented by Larry Hench et al., which presents higher bioactivity. A possible application of this bioglass in the treatment o...
Extensive Investigation on the Effect of Niobium Insertion on the Physical and ...
Hammami, Imen; Gavinho, Sílvia Rodrigues; Pádua, Ana Sofia; Lança, Maria do Carmo; Borges, João Paulo; Silva, Jorge Carvalho; Sá-Nogueira, IsabelDental implants have emerged as one of the most consistent and predictable treatments in the oral surgery field. However, the placement of the implant is sometimes associated with bacterial infection leading to its loss. In this work, we intend to solve this problem through the development of a biomaterial for implant coatings based on 45S5 Bioglass® modified with different amounts of niobium pentoxide (Nb2O5)....
An Eco-Friendly Process to Extract Hydroxyapatite from Sheep Bones for Regenera...
Gavinho, Sílvia Rodrigues; Bozdag, Mehmet; Kalkandelen, Cevriye; Regadas, Joana Soares; Jakka, Suresh Kumar; Gunduz, Oguzhan; Oktar, Faik NuzhetHydroxyapatite (HA) promotes excellent bone regeneration in bone-tissue engineering, due to its similarity to bone mineral and its ability to connect to living tissues. These factors promote the osteointegration process. This process can be enhanced by the presence of electrical charges, stored in the HA. Furthermore, several ions can be added to the HA structure to promote specific biological responses, such a...
Antibacterial Biomaterial Based on Bioglass Modified with Copper for Implants C...
Hammami, Imen; Gavinho, Sílvia Rodrigues; Jakka, Suresh Kumar; Valente, Manuel Almeida; Graça, Manuel Pedro Fernandes; Pádua, Ana SofiaBiofilm-related implant infections pose a substantial threat to patients, leading to inflammation in the surrounding tissue, and often resulting in implant loss and the necessity for additional surgeries. Overcoming this implantology challenge is crucial to ensure the success and durability of implants. This study shows the development of antibacterial materials for implant coatings by incorporating copper into...
Análises bibliométricas aplicadas ao estudo da secagem solar de alimentos
Menezes, Victor Augusto Cavalcante Bezerra; Graça, Manuel Pedro Fernandes; Freire, Francisco Nivaldo Aguiar; Maia Júnior, Paulo Herbert FrançaAnálises bibliométricas são bastante úteis quando se deseja evidenciarrelações existentes entre diversas publicações que tratamde umdeterminado assunto(do mais abrangente ao mais específico).As análises podem ser de diversos tipos, tais como de citação e co-citação, easrelaçõespodem ser estabelecidas tendo como base unidades de análisetais comoautores, organizações (centros de pesquisa e universidades), países ...
Photoelectrodes with titanate nanotubes sensitized by mesoporphyrin derivative ...
Souza, Antonio Paulo Santos; Almeida, Ana Fabíola Leite; Conegero, Leila de Souza; Viana, Bartolomeu Cruz; Ferreira, Odair PastorTitanate nanotubes (TiNTs) with the chemical composition Na2Ti3O7.nH2O (NaTiNT) were obtained through a hydrothermal method in highly alkaline medium. Protonated titanates nanotubes (H-TiNTs), with the composition H2Ti3O7.nH2O, were prepared by ion exchange reaction through a suspension of Na2Ti3O7nH2O nanotubes in HCl medium, promoting the exchange of Na+ ions by H+. Both Na2Ti3O7.nH2O and H2Ti3O7.nH2O produc...
Multiferroic interfaces in bismuth ferrite composite fibers grown by laser floa...
Figueiras, Fábio Gabriel; Dutta, Dikabar; Ferreira, N. M.; Costa, Florinda Mendes da; Graça, Manuel Pedro Fernandes; Valente, Manuel AlmeidaIn this work we explore the formation of enhanced multiferroic interfaces in bismuth ferrite crystalline fibers grown by laser floating zone technique. An underlying mechanism of self-segregation during the fibers growth process enables to establish a textured microstructure of a dominant BiFeO3 phase bordered by the presence of Bi25FeO40 secondary phase. The crystallites c axis of the BiFeO3 phase shows a pref...
Electrical and dielectric analysis of phosphate based glasses doped with alkali...
Graça, Manuel Pedro Fernandes; Melo, Bruno Miguel Gonçalves; Prezas, Pedro Rafael dos Santos; Valente, Manuel Almeida; Freire, Francisco Nivaldo AguiarIn this work, new phosphate glasses with the molar composition 20.7P2O5–17.2Nb2O5–13.8WO3–34.5A2O– 13.8B2O3 where A = Li, Na and K were prepared using the melt quenching technique. These types of glasses have potential to absorb hydrogen in its structure, whichmakes thempromisingmaterials to be used as electrolytes in intermediate temperature fuel cells. Additionally, niobium phosphate glasses can also have app...