DALTON GIOVANNI NOGUEIRA DA SILVA

DALTON GIOVANNI NOGUEIRA DA SILVA

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Study on the radiation exposure of Portable X-ray Fluorescence
2023 - DIAS, F.S.; GIOVANNI, D.N.S.; POTIENS JUNIOR, A.J.; RODRIGUES JUNIOR, O.; POTIENS, M.P.A.; ZAMBONI, C.B.
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.
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.
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.
Traceability of the propolis produced by Scaptotrigona Aff Postica bee from Brazil using NAA technique
2022 - ZAMBONI, C.B.; GIOVANNI, D.N.S.; PECEQUILO, B.R.S.; ESPOSITO, S.E.; PIMENTA, D.C.; SIMONS, S.M.
In the Northeast, meliponiculture presents itself as one of the zootechnical activities that has grown the most in recent years, due to its low implementation and maintenance cost, as well as a quick financial return. Meliponiculture is the creation of stingless bees (Meliponines) for the production and commercialization of beehives, honey, propolis, pollen and resins, in addition to these bees being the main agents of pollination and conservation of local biodiversity. The propolis produced by the Scaptotrigona Aff Postica bee (popularly known as the tubi bee) have several medical applications (bactericidal, fungicidal and virucidal), in addition to its use in the nutritional field. This species is found in the mainly in the Barra do Corda County (Maranhão) and it is the major source of income in the northeast region. Nowadays, food authentication has been a concern of producers and consumers around the world. For this reason, there is a growing need for reliable analytical techniques to provide an answer about food authenticity. With the goal for determining chemical descriptors for geographic origin (standardization), nuclear techniques are useful analytical tools with a highlight for Neutron Activation Analysis (NAA). The NAA measurement was performed in the nuclear reactor (IEA-R1, 3-4 MW, at IPEN). Propolis samples were collected monthly during a one year, directly from beehives of Scaptotrigona Aff Postica in a meliponary of Barra do Corda city (5° 30' 21'' S and 45° 14' 6'' W). The results were compared with two other species from south region. The database will aid in fraud detection of the propolis from the northeast region in Brazil.
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.