DALTON GIOVANNI NOGUEIRA DA SILVA

DALTON GIOVANNI NOGUEIRA DA SILVA

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Tecnologias analíticas instrumentais para a investigação de madeira
2024 - ZAMBONI, CIBELE B.; GIOVANNI, DALTON; SILVA, PAULO S.C. da; MOREIRA, EDSON G.; LOBOS, CRISTIAN M.V.; SARRIES, GABRIEL A.; NOGUEIRA, ANA R. de A.; BACCHI, MARCIO A.; MARTINELLI, LUIZ A.; FERNANDES, ELISABETE A. de N.
A madeira é uma commodity produzida no Brasil que tem relevância no cenário econômico entretanto o impacto ambiental, devido à expansão das áreas de exploração, tem gerado preocupação com o desmatamento e consequente alterações ambientais, principalmente na região amazônica. Na presente investigação foram testadas três metodologias analíticas instrumentais para autenticação da madeira nativa da Amazônia com base em sua caracterização físico-química. O emprego combinado das técnicas espectrométricas como Fluorescência de Raios X (FRX), bem como análise de compostos orgânicos por Espectroscopia Raman (ER) e Infravermelho (IR) mostraram-se eficiente para uso em metrologia forense, disponibilizando dados que podem ser usados na identificação de madeira nativa, compondo metodologia alternativa para monitoração dos problemas enfrentados na região amazônica (desmatamento, queimadas e invasões ilegais). Além disso, a metodologia estabelecida no presente estudo pode ser aplicada a outras regiões do Brasil, que também produz esse tipo de commodity e enfrentam os mesmos problemas.
X- ray experimental set-up for in-vitro nail test
2023 - ZAMBONI, C.B.; GIOVANNI, D.N.S.; ALMEIDA, M.R.; TODO, A.S.; SABARA, F.; RODRIGUES JUNIOR, O.
In this investigation, the elements Ca and S were evaluated in a single nail clipping using compact and portable X-ray spectrometer model X-123 SDD with Ag target. Experimental conditions for current, voltage and excitation time were investigated. These analyses can be useful for a variety of applications, including nutritional and medical diagnosis, such as, the evaluation of bone dysfunctions by measurement of Ca (bone decalcification) and S for nutrition evaluations (collagen production). This analysis offers some benefits comparatively to blood and serum analyses, such as, non-invasive collection, fast analyses (minutes) and low cost. In addition, nail clippings are simple to obtain, easy to store, and easy to transport. This pilot study show a positive expectation for clinical application using in-vitro nail test.
Young Scientist Project presents Neutron Life
2023 - ZAMBONI, CIBELE B.; GIOVANNI, DALTON N.S.; KOKA, ANA C.; STANOJEV, MARCO
The Young Scientist Project was created in 2019, by the team of the Spectroscopy and Spectrometry of Radiation Laboratory (LEER/IPEN), with the proposal to implement nuclear knowledge in academia and for the general public. The objective is to develop alternative proposals for knowledge, application and dissemination of nuclear physics using social networks. The website www.jovemcientista.com.br design involves four menus: REPORTS where researchers talk about their career and perspectives in the field; NUCLEAR MINUTE: where nuclear physics concepts are covered in one-minute videos; CURIOSITIES: a space where various themes are presented, including several nuclear applications; INTERVIEWS: conducted by students to discuss its work and a COMMUNICATION CHANNEL with the entire team. All activities involve the participation of students from scientific initiation to post-doc and the content produced is available on social networks YouTube (Jovem Cientista), Instagram (@jovemcientista.com.br) associated with a Facebook page Facebook (@jovemcientista.com.br), TikTok (@jovemcientista.com.br) and by LinkedIn and Twitter in the editors’; profile. Now, we are present a new menu NEUTRON LIFE whose content is produced mainly for graduate students. The idea is to present topics related to neutron physics in a relaxed way, through the elaboration of videos and comic strips. Since the implementation of the Young Scientist Project, interaction with students and the public has been positive, helping to demystify and disseminate nuclear physics.
Multi-analytical X-ray study of the honorary decoration of the Order of Christ
2023 - ZAMBONI, CIBELE B.; SILVA, DALTON G.N. da; BOGNAR, MARTA L.; SILVA NETO, GALDINO V. da
The analysis of cultural heritage objects can generate information about techniques of minting of the time, giving information not only on chronology but also regarding preparation methodology, and provenance. In this investigation, three honorable mentions (metal artifacts) of the order of Christ (cross, lady's and gentlemen's medal) were performed using Energy Dispersive X-ray Fluorescence (EDXRF) technique. This analysis were performed with a portable Amptek assemble of Si-drift XR-100SSD (25 mm2 × 500 μm) detector, equipped with a 12.5 μm Be entrance window, pre-amplifier and digital pulse multichannel processor and Ag target. Analytical parameters were 5 μA and 30 kV for 180 s at 2 mm distance to the target. Points distributed in distinct parts were analyzed in each of the metal artifact. The WinQxas software was employed for spectral analyses. These data provide to curators and historians knowledge for cataloging and subsidies for correct storage. In addition, they can be used to identify forgeries (heritage appreciation).
Multielemental characterization of the pollen produced by Scaptotrigona aff postica bee from Brazil using EDXRF technique
2023 - SILVA, DALTON G.N. da; ZAMBONI, CIBELE B.; PECEQUILO, BRIGITTE R.S.; ESPOSITO, SELENE E.; PIMENTA, DANIEL C.; SIMONS, SIMONE M.
The objective of this investigation was to perform a multielemental characterization of the pollen produced by Scaptotrigona aff Postiça Bee (popularly known as “tubi”). In recent years, the demand for natural and healthy products has grown significantly and products from Meliponiculture (creation of stingless bees) have started to be consumed on a larger scale in Brazil. Specifically, pollen has gained prominence in the nutritional field for being a protein source and rich in carbohydrates, lipids, mineral trace elements, fibers, hormones and vitamins, but scientific research is still scarce, especially regarding studies of its specific composition. The aim of this investigation was to evaluate the content of inorganic elements (multielemental analysis) in pollen from “tubi” bees. Pollen samples were collected during a one year, in a meliponary of Barra do Corda city, in the state of Maranhão. The EDXRF analyzes were carried out using an X-Ray Fluorescence spectrometer (X-123SDD, Amptek), constituted by a Silicon detector coupled a mini X-ray tube (Ag). These data are the first estimates of mineral trace elements in this natural product and provide benefits to beekeepers regarding their characteristic specifications. In addition contributes with relevant data in the nutritional field.
Application of the X-ray fluorescence analysis to determine the elemental composition of Brazilian Olympic coins
2023 - SILVA, ANA C.K. de S.; ZAMBONI, CIBELE B.; ALMEIDA, MATEUS R. de; SILVA, DALTON G.N. da
In this investigation, the elemental composition of Brazilian Olympic coins was investigated using Energy Dispersive X-ray Fluorescence (EDXRF) analytic technique. From the release of Olympic albums (2014, 2015, and 2016) the demand for these coins has increased and some can be worth up to 7000% more than their normal value. The analysis was performed using a compact X-ray spectrometer model X-123 SDD with Ag target. The characteristic X-ray fluorescent intensity of Ka lines were measured with a Si Drift detector (25 mm² x 500 μm) with Be window (12.5 μm). For the spectrometer calibration, certified standard solutions from Z = 14 to Z = 51 were evaluated. The results were compared with coins in current circulation. All the spectral analysis was performed using WinQxas software. The spectral analysis of Olympic coins shows Cr, Mn, Fe and Cu as majorities and peaks of various elements as traces. The 2014 and 2015 Olympic coins groups exhibited similar surface compositions for majorities and trace elements (V, Ni, Mo, Ag, In, Sn, Ce, Nd, Ir and Pb), while the 2016 group coins exhibited Nb presence as a trace element. Some differences were also identified when the comparison was made with current coins. These data provide curators with information for cataloging as well as being used to identify forgeries (heritage appreciation), important for collectors.
Uso de mini-espectrômetro de fluorescência de raios X como alternativa para a prática clínica de dialisados
2023 - SOUZA, CATARINA da S.; ZAMBONI, CIBELE B.; MOURA, LARISSA A.S.; METAIRON, SABRINA; SILVA, DALTON G.N. da
Neste estudo, o uso de equipamento compacto e portátil, baseado na tecnologia de Fluorescência de Raios X, foi empregado para execução de análises bioquímicas (dosagens de íons) em microamostras de fluidos corpóreos depositadas em papel. Foi realizada a análise simultânea de íons de relevância clínica e nutricional (Ca, Cl, Fe, K, P e S), em sangue total de pacientes com insuficiência renal crônica (IRC) submetidos a tratamento dialítico. Durante a investigação as concentrações obtidas em sangue total levaram a resultados que corroboram com o quadro clínico obtido pelas análises convencionais. Com os dados do presente foi possível elaborar uma discussão sobre a viabilidade de uso deste equipamento para a realização desses exames bioquímicos em Unidades Básicas de Saúde Fluviais (UBSF), gerando melhorias na qualidade de vida de populações ribeirinhas, bem como no âmbito econômico em função de sua aplicabilidade com menor custo. Descritores: Íons, Sangue, Análise Clínica.
Ions and metal dosage in human health
2022 - ZAMBONI, CIBELE B.; METAIRON, SABRINA; GIOVANNI, DALTON N.S.; MEDEIROS, JOSE A.G. de; AZEVEDO, MARIA R.
Comparação de desempenho do espectrômetro portátil de fluorescência de raios-X utilizando alvos de Au e Ag para análise de amostras na área da saúde
2022 - TASSO, ORION G.; ZAMBONI, CIBELE B.; SILVA, ANA C.K. de S.; MEDEIROS, JOSE A.G. de; SILVA, DALTON G.N. da
Este trabalho teve por objetivo avaliar o desempenho do espectrômetro portátil e compacto de Fluorescência de Raios-X (pFRX), para dosagem de íons em amostras biológicas de interesse na área da saúde (prioritariamente fluidos corpóreos como soro e urina), utilizando alvos de Prata (Ag) e Ouro (Au). O foco das comparações foi direcionado às análises quantitativas de elementos de relevância clínica e nutricional (prioritariamente a dosagem de Ca, Cl, Fe, K, P e S). Para este estudo foram avaliados (para cada alvo) os parâmetros: linearidade, reprodutibilidade, acurácia, sensibilidade e limite de detecção. Essas investigações permitiram a realização de um estudo comparativo entre os alvos, com a finalidade de fornecer subsídios que permitem a escolha adequada do alvo (Ag e/ou Au), agilizando as medidas além de fornecer resultados mais precisos. Os resultados de FRX em soro e urina formam comparados com as dosagens obtidas pela técnica de Análise por Ativação com Nêutrons e apresentaram boa concordância.
NAA and XRF techniques to investigate artistic paints
2022 - KOKA, A.C.S.S.; ZAMBONI, C.B.; GIOVANNI, D.N.S.; REDÍGOLO, M.M.
In this study, the multielemental characterization of artistic blue paints from the 90's and currently available ones in the Brazilian market was carried out using the Energy Dispersion X-Ray Fluorescence (EDXRF) and Neutron Activation Analysis techniques (NAA). These results aim to establish a reference database in the field. The EDXRF measurements was performed using portable X-ray spectrometer with Ag X-ray tube associated with a Si Drift detector (25 mm2 x 500 μm) with Be window (12.5 μm). The artistic paint samples were irradiated for 300 s using 30 kV and 5μA excitation. The quantitative analysis was performed using WinQXas software program (IAEA, version 1.3). The NAA measurements were performed in the nuclear reactor IEA-R1 (3.5- 4.5MW, pool type) at IPEN/CNEN-SP. Each sample was irradiated from minutes to hours and gamma counting was performed using HPGe detector (ORTEC-GEM 60195) coupled to an MCA (ORTEC - 919E). Concentration of all elements was obtained using the ATIVAÇÃO software. The results obtained by both techniques are in good agreement, in addition to being complementary. However, they do not correspond to the elemental content description provided by the manufacturer.