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Item Crystalline structure, morphology, and adherence of thick TiO2 films grown on 304 and 316L stainless steels by atomic layer deposition(MDPI) Marques, Vagner Eduardo Caetano; Manfroi, Lucas Augusto; Vieira, Angela Aparecida; Pereira, André Luis de Jesús; Marques, Francisco das Chagas; Vieira, LúciaTitanium dioxide (TiO2) thin films are widely used in transparent optoelectronic devices due to their excellent properties, as well as in photocatalysis, cosmetics, and many other biomedical applications. In this work, TiO2 thin films were deposited onto AISI 304 and AISI 316L stainless steel substrates by atomic layer deposition, followed by comparative evaluation of the mixture of anatase and rutile phase by X-ray diffraction, Raman maps, morphology by SEM-FEG-AFM, and adhesion of the films on the two substrates, aiming to evaluate the scratch resistance. Raman spectroscopy mapping and X-ray diffraction with Rietveld refinement showed that the films were composed of anatase and rutile phases, in different percentages. Scratch testing using a diamond tip on the TiO2 film was employed to evaluate the film adherence and to determine the friction coefficient, with the results showing satisfactory adherence of the films on both substrates.Item Molhabilidade de Não Tecido Eletrofiado Contendo Nanopartículas de Prata para Uso em Filtros(2023) Shimada, Yoshio Manoel Nunes; Silva, Daniele Cristina da; Bustamante, Gabriel Costa; Vieira, Angela Aparecida; Vieira, LúciaItem Scratch and wear behaviour of Co-Cr-Mo alloy in ringer’s lactate solution(MDPI) Silva, Raimundo; Santos, Marcos Dantas dos; Madureira, Rui; Soares, Rui; Neto, Rui; Vieira, Angela Aparecida; Gonçalves, Polyana Alves Radi; Leite, Priscila Maria Sarmeiro Corrêa Marciano; Vieira, Lúcia; Viana, FilomenaCobalt–chromium–molybdenum (Co-Cr-Mo) alloy is a material recommended for biomedical implants; however, to be suitable for this application, it should have good tribological properties, which are related to grain size. This paper investigates the tribological behaviour of a Co-Cr-Mo alloy produced using investment casting, together with electromagnetic stirring, to reduce its grain size. The samples were subjected to wear and scratch tests in simulated body fluid (Ringer’s lactate solution). Since a reduction in grain size can influence the behaviour of the material, in terms of resistance and tribological response, four samples with different grain sizes were produced for use in our investigation of the behaviour of the alloy, in which we considered the friction coefficient, wear, and scratch resistance. The experiments were performed using a tribometer, with mean values for the friction coefficient, normal load, and tangential force acquired and recorded by the software. Spheres of Ti-6Al-4V and 316L steel were used as counterface materials. In addition, to elucidate the influence of grain size on the mechanical properties of the alloy, observations were conducted via scanning electron microscopy (SEM) with electron backscatter diffraction (EBSD). The results showed changes in the structure, with a reduction in grain size from 5.51 to 0.79 mm. Using both spheres, the best results for the friction coefficient and wear volume corresponded to the sample with the smallest grain size of 0.79 mm. The friction coefficients obtained were 0.37 and 0.45, using the Ti-6Al-4V and 316L spheres, respectively. These results confirm that the best surface finish for Co-Cr-Mo alloy used as a biomedical implant is one with a smaller grain size, since this results in a lower friction coefficient and low wear.Item Wear Rate, Tribo-Corrosion, and Plastic Deformation Values of Co-Cr-Mo Alloy in Ringer Lactate Solution(MDPI) Silva, Raimundo Nonato Alves; Neto, Rui; Vieira, Angela Aparecida; Leite, Priscila Maria Sarmeiro Corrêa Marciano; Radi, Polyana Alves; Silveira, Carolina Hahn da; Santos, Marcos Dantas dos; Viana, Filomena; Vieira, LúciaThis study investigates the tribocorrosion performance of a cast Co-Cr-Mo alloy prepared using casting and electromagnetic stirring (EMS) at specific frequencies. The tribocorrosion behaviour of the alloy was evaluated when exposed to Ringer’s lactate solution to optimize the EMS parameters and improve its properties. The research focuses on biomedical implant applications and explores how EMS affects alloy wear and corrosion resistance. As did the friction coefficient and wear volume, the wear rate of samples produced with EMS frequencies of 75 Hz and 150 Hz decreased. These improvements are attributed to the ability of EMS to refine grain size and homogenize the microstructure, thereby increasing the resistance to tribocorrosion. Techniques such as scanning electron microscopy (SEM) and profilometry were used for surface and wear analysis, while mechanical properties were evaluated through instrumented indentation tests. The findings confirm that EMS improves the alloy’s durability and tribocorrosion resistance, making it highly suitable for demanding biomedical applications such as joint replacements. This highlights the importance of advanced manufacturing techniques in optimizing biomedical alloys for simulated body conditions.Item Plano de Desenvolvimento Institucional da Univap 2021-2025(2021) ; Beltrame Junior, Milton; Bicudo, Silene Fernandes; Solano, Edgar; Vieira, Lúcia; Aquino, Luiz Carlos Andrade de; Peixoto, Manoel Otelino da Cunha; Paula, Maria Tereza Dejuste de; Camargo, Rafaella Guimarães Moraes; Costa, Sandra Maria Fonseca da; Canhoto, Alberto Eugênio; São José dos CamposO Plano de Desenvolvimento Institucional (PDI) é um instrumento dinâmico de reflexão, planejamento e consulta para nortear estrategicamente o conjunto das ações institucionais da Univap, visando realizar sua missão fundamentada em seus valores e princípios institucionais próprios. O PDI 2021-2025 projeta o esforço institucional da Univap, no atual momento de sua história, para consolidar sua identidade comunitária de instituição que busca acolher e ser acolhida pelo meio social no qual está inserida, tendo como eixo central a articulação entre ensino, pesquisa, extensão e gestão de excelência, voltados aos interesses da comunidade, com sustentabilidade de suas ações e processos.Item Chemical constituents and cytotoxic activity of Eugenia involucrata DC. infusion(Concilium) Barzotto, Ionete Lúcia Milani; Oliveira, Simone Maria Menegatti de; Silva, Newton Soares; Almeida, Rafaela Takako R.; Pilau, Eduardo J.; Delabeneta, Matheus F.; Vieira, LúciaIn this work, the chemical constituents of the infusion from the leaves of Eugenia involucrata DC. (Myrtaceae) were elucidated using ultra-high-performance liquid chromatography coupled to high resolution mass spectrometry (UHPLC-MS/MS), as well as Fourier transform infrared spectroscopy (FTIR). The toxicity of the infusion was evaluated using the brine shrimp (Artemia salina) lethality test. Nineteen chemical compounds were identified by UHPLC-MS/MS: gallic acid; quinic acid; epicatechin; gallocatechin; (epi)afzelechin-(epi)catechin; quercetin-3-O-rhamnoside (quercitrin); citric acid; tryptophan; aconitic acid; (-)-epicatechin-(4β→8)-(-)-epicatechin (procyanidin B2); rutin; quercetin-3-O-glucoside; naringenin-7-O-glucoside (prunin); coumaric acid; azelaic acid; quercetin; naringenin; kaempferol-3-O-glucoside (astragalin). FTIR analysis revealed bands attributed to phenols and alcohols, alkanes and carboxylic acids, flavonoids and polyphenols, aromatic compounds, and aliphatic amines. According to the results, the infusion of E. involucrata DC. demonstrated atoxicity and contained chemical components that could be useful in the development of new therapeutic or herbal agents.Item Processo para produção de lipídeos para uso em biocombustíveis utilizando a fração orgânica de lixo urbano(2024) Pradella, José Geraldo da Cruz; Vieira, Lúcia; Costa, Maricilia Silva; Bosso, Geisler Chbane; Jofre, Jorge Benedito Freire; Souza, Jorge Damião de; Sousa, Juçara Cristina Pereira; Sonnewend, Lais; Barboza, Maria Antonia de Mello e Albuquerque; Couto, Rafaela; Cordeiro, Thaina Barbosa de LimaItem Revestimento compósito de alumínio-grafeno para barramentos blindados de alumínio e método de produção(2024) Bosso, Geisler Chbane; Vieira, Lúcia; Morel, Renato Kogima Francesa; RM ENERGY INDÚSTRIA E COMÉRCIO DE EQUIPAMENTOS ELÉTRICOS; FUNDAÇÃO VALEPARAIBANA DE ENSINOItem Tribocorrosion studies on DLC films with silver nanoparticles for prosthesis applications(IOP Publishing) Radi, Polyana Alves; Vieira, Lúcia; Leite, Priscila Maria Sarmeiro Corrêa Marciano; Trava-Airoldi, Vladimir Jesus; Massi, Marcos; Reis, Danieli Aparecida PereiraMetals and their alloys are very important for orthopedic applications, and the basic requirements for a successful implant are chemical stability, mechanical behavior, and biocompatibility in body fluids and tissues. For prosthesis applications, the corrosion resistance of metals is one of the major prerequisites to avoid impairment of the material properties due to degradation. The combined action of corrosion and wear on the material is called tribocorrosion and DLC (Diamond-Like Carbon) films have been extensively studied to increase prosthesis biocompatibility and to protect from corrosion. Additionally, DLC coatings can prevent the prosthesis to release toxic elements due to plastic deformation and corrosion. This paper is about tribocorrosion studies on DLC and DLC-Ag (DLC containing silver nanoparticles) on Ti-6Al-4V substrates. These films were obtained by PECVD (Plasma Enhanced Chemical Vapor Deposition) using hexane as a precursor. The tribocorrosion behavior of uncoated and coated samples was investigated in the reciprocating mode in Ringer's lactate solution. From the polarization test results, the protective efficiency of the film was calculated. Silver nanoparticles improved the corrosion resistance of the films. The protective efficiency was 15 and 19% for DLC and DLC-Ag films, respectively.Item Ionizographic detector for Breast Cancer Diagnosis(CDRR Editors) Matos, Helton Gírio; Ramos, Marco Antonio Ramirez; Vieira, Lúcia; Pires, Ary OliveiraEvery day the number of cancer victims increases. In 2020 alone, 626,030 people were affected in Brazil, according to estimates by the National Cancer Institute (INCA). The only way to reduce these numbers is early diagnosis. In the present study, a invention called Ionizographic Detector is described, which performs Positron Emission Tomography (PET) producing metabolic information in breast nodules. This device enables accurate diagnosis of breast nodules regarding its malignancy. To prove its effectiveness, a comparative evaluation was made between the Ionizographic Detector and the Positron Emission Tomography/Computerized Tomography (PET-CT) for analysis of the metabolic data in breast nodules. The research is being carried out with 20 patients who have histopathologically documented breast cancer. From the results it will be possible to prove the device’s efficacy. It will thus enable an accurate and low-cost malignancy diagnosis option. The Ionizographic Detector can be hybridized with some anatomical imaging technology, such as Ultrasound (US). With this, it is possible to promote greater access to accurate diagnoses, significantly increasing the possibility of early diagnoses, enabling a cure or a better prognosis for the patient.