Por favor, use este identificador para citar o enlazar este ítem:
https://repositorio.ufpe.br/handle/123456789/64775
Comparte esta pagina
Registro completo de metadatos
Campo DC | Valor | Lengua/Idioma |
---|---|---|
dc.contributor.advisor | VINHAS, Glória Maria | - |
dc.contributor.advisor | SARUBBO, Leonie Asfora | - |
dc.contributor.author | SOUZA, Thais Cavalcante de | - |
dc.date.accessioned | 2025-08-01T12:14:08Z | - |
dc.date.available | 2025-08-01T12:14:08Z | - |
dc.date.issued | 2025-02-27 | - |
dc.identifier.citation | SOUZA, Thaís Cavalcante de. Material híbrido de celulose bacteriana com magnetita: produção, otimização e aplicação. 2025.Tese (Doutorado em Ciências dos Materiais) – Universidade Federal de Pernambuco, Recife, 2025. | pt_BR |
dc.identifier.uri | https://repositorio.ufpe.br/handle/123456789/64775 | - |
dc.description.abstract | saturação de 50,38 emu/g, um valor 73,7% maior que o apresentado pelas partículas não otimizadas, um menor diâmetro de cristalito, de 6,96 nm, e os materiais de CB produzidos atingiram maiores magnetizações de saturação, entre 29,69 a 36,22 emu/g. Estes materiais foram testados para a aplicação em blindagem contra EMI, e apresentaram resultados que indicam a possibilidade de sua utilização em pastilhas multicamadas, como matriz para a adição de outros dopantes, e para bloquear a poluição secundária, gerada pela reflexão de ondas eletromagnéticas. | pt_BR |
dc.language.iso | por | pt_BR |
dc.publisher | Universidade Federal de Pernambuco | pt_BR |
dc.rights | openAccess | pt_BR |
dc.rights.uri | https://creativecommons.org/licenses/by-nc-nd/4.0/ | pt_BR |
dc.subject | Celulose Bacteriana | pt_BR |
dc.subject | Magnetismo | pt_BR |
dc.subject | Magnetita | pt_BR |
dc.title | Material híbrido de celulose bacteriana com magnetita: produção, otimização e aplicação | pt_BR |
dc.type | doctoralThesis | pt_BR |
dc.contributor.advisor-co | COSTA, Andréa Fernanda de Santana | - |
dc.contributor.authorLattes | http://lattes.cnpq.br/0084771728068291 | pt_BR |
dc.publisher.initials | UFPE | pt_BR |
dc.publisher.country | Brasil | pt_BR |
dc.degree.level | doutorado | pt_BR |
dc.contributor.advisorLattes | http://lattes.cnpq.br/6404643744960977 | pt_BR |
dc.contributor.advisorLattes | http://lattes.cnpq.br/4691045388698504 | pt_BR |
dc.publisher.program | Programa de Pos Graduacao em Ciencia de Materiais | pt_BR |
dc.description.abstractx | Bacterial cellulose (BC) is a biopolymer obtained through fermentation, possessing unique properties that make it an ideal matrix for the production of advanced hybrid materials, such as magnetic films. The production of magnetic BC biofilms typically involves the incorporation of magnetite nanoparticles through processes like in situ and ex situ coprecipitation. The parameters of each method influence the magnetic characteristics of the material, which can be applied in various fields. Among these applications, electromagnetic interference (EMI) shielding stands out as a growing area due to the increasing use of EMI-based technologies and their impacts on health and the environment. In this study, hybrid bacterial cellulose materials incorporated with magnetite nanoparticles were developed. Initially, different fermentation media were investigated for BC film production, where the culture medium enriched with corn steep liquor showed higher fiber production. Subsequently, methods for the synthesis and incorporation of magnetite nanoparticles into BC biofilms were explored, evaluating both in situ and ex situ coprecipitation methods in intact and processed biofilms. The material obtained via ex situ coprecipitation with processed BC demonstrated satisfactory results, such as high saturation magnetization and better reaction control. This methodology was optimized by adopting a higher stirring speed, altering the reagent ratios, and introducing a purification step for the obtained nanoparticles. As a result, the particles exhibited superparamagnetic behavior, with a saturation magnetization of 50.38 emu/g, 73.7% higher than the non-optimized particles, and a smaller crystallite diameter of 6.96 nm. The produced BC materials achieved higher saturation magnetizations, ranging from 29.69 to 36.22 emu/g. These materials were tested for EMI shielding applications, showing promising results indicating their potential use in multilayer pellets, as matrices for the addition of other dopants, and for blocking secondary pollution generated by electromagnetic wave reflection. | pt_BR |
dc.contributor.advisor-coLattes | http://lattes.cnpq.br/1529389745658217 | pt_BR |
Aparece en las colecciones: | Teses de Doutorado - Ciências de Materiais |
Ficheros en este ítem:
Fichero | Descripción | Tamaño | Formato | |
---|---|---|---|---|
TESE Thais Cavalcante de Souza.pdf | 5,35 MB | Adobe PDF | ![]() Visualizar/Abrir |
Este ítem está protegido por copyright original |
Este ítem está sujeto a una licencia Creative Commons Licencia Creative Commons