DALTON GIOVANNI NOGUEIRA DA SILVA

DALTON GIOVANNI NOGUEIRA DA SILVA

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X-ray investigation of graphic art
2023 - SILVA, ANA C.K. de S.; ZAMBONI, CIBELE B.; SILVA, DALTON G.N. da
X-rays produced by electron ionization provide an analytical tool that can assist investigations in the field of Artistic and Cultural Heritage. In this study, the technique of Energy Dispersive X-ray Fluorescence (EDXF) was employed to investigate collections of postcards from the 1960s produced in Brazil, London and Uruguay. The collections belong to private collections and were made available for analysis at the Radiation Spectroscopy and Spectrometry Laboratory of the Institute for Nuclear and Energy Research (IPEN). This technique is non-destructive and allows the identification of chemical elements present in the different chemical formulations used in the printing industries of each country in the process of preparing postcards. This information allows tracing their origin and identifying copies/fakes, which enables their cataloging and registration for exhibition, as well as providing subsidies for conservators and restorers regarding the preservation and storage of these artistic materials.
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.
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.
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.
Young Scientist Project
2022 - GIOVANNI, D.N.S.; KOKA, A.C.S.S.; ALMEIDA, M.R.; ZAMBONI, C.B.
The use of Information and Communication Technologies (ICT) has facilitated the dissemination of nuclear knowledge and, at the same time, improved relations between specialists working in different areas of science. The growing number of initiatives, on the part of Research Centers, Universities, and even on an individual basis has been positive through social networks, websites, and blogs. The Young Scientist Project was created in 2019, by the team of the Spectroscopy and Spectrometry of Radiation Laboratory at IPEN, with the proposal to implement nuclear knowledge. The aim is to present alternative proposals for knowledge, application, and dissemination of science, with an emphasis on demystifying the nuclear sciences. The website (www.jovemcientista.com.br) design involves four menus: REPORTS where researchers talk about their career, challenges, and perspectives in the field; NUCLEAR MINUTE: where nuclear physics concepts are covered in one-minute videos; CURIOSITIES: a space where various topics are presented, whose objective is to dialogue between the various areas of scientific knowledge. In addition, within this menu, scientific content from other media is available in GARIMPO, and the menu INTERVIEWS: conducted by students to discuss its work. All the content produced on this website is available in various social media, such as, the YouTube channel (Jovem Cientista), the profile on Instagram (@jovemcientista.com.br) associated with a Facebook page (@jovemcientista.com.br), the profile on TikTok (@jovemcientista.com.br) and by Linkedin and Twiter in the editors' profile. In addition, the site provides a communication channel with the entire team. Since its creation, content has been developed in the nuclear area from basic concepts to applications of radiation in different areas, such as, the environment, dosimetry, and health, among others. The possibility of using ICT has been positive, helping to demystify and disseminate nuclear physics.
Analysis of XX century gold-silver coins by X-ray fluorescence and neutron tomography
2022 - ZAMBONI, C.B.; STANOJEV, M.; KOKA, A.C.S.S.; GIOVANNI, D.N.S.; REDÍGOLO, M.M.
X-ray fluorescence (XRF) is a technique capable of analyzing chemical elements on metallic surfaces, providing fast, sensitive, and reliable results while neutron tomography (NT) allows to investigate its internal structure by three-dimensional images. Both techniques are powerful tools for non-destructive analysis of artistic and historical objects. In this study, we explored the combined use of these techniques to investigate a set of Brazilian gold-silver coins dating from the early 20th century (1913-1938). This set of coins was select due to the lack of data related to their composition and origin. These data provide information to museologists for better cataloging / registration of fundamental information. Moreover, this information is vital for collectors and marchands in authentication processes. The X-Ray Fluorescence analysis was performed using X-Ray Spectrometer with gold (Au) and silver (Ag) targets. The excitation conditions were optimized in 30 kV and 5 μA and counting time of 200 s. A NT facility is installed at the beam-hole (BH-14) of the 4.5 MW pool-type IEA-R1 nuclear research reactor at IPEN (SP, Brazil). It consists of a 6LiF (ZnS) scintillator screen, a glass-based plane mirror, a video camera (16bit, 1024 x1024 pixels, cooled CCD) and a collimator to reduce the neutron beam size in the BH-14. The experimental conditions established were: 8 x106 ns-1 cm-2 (neutron flux), irradiation time/image of 1s, spatial resolution of 263 ± 35 μ and time tomography of 400s. The three-dimensional images were treated using dedicated software (OctopusV8.0 and VG studio Max2.2). The combined results bring information of elemental composition and 3D images highlight the conservation state of the pieces, being of great aid to conservators and museologists.
Propostas alternativas para o conhecimento e uso da Energia Nuclear
2022 - ZAMBONI, C.B.; GIOVANNI, D.N.S.; KOKA, A.C.; ALMEIDA, M.R.; MEDEIROS, I.M.M.A.; LEAO, A.R.