DANIEL VILLANI
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Artigo IPEN-doc 28208 Development of a 3D printed anthropomorphic skull phantom for clinical photons beam dosimetry2021 - ALMEIDA, S.B.; VILLANI, D.; CAMPOS, L.L.Artigo IPEN-doc 26749 Study on electronic equilibrium of 137Cs gamma radiation for 3D printed phantoms using OSL dosimetry2019 - VILLANI, D.; RODRIGUES JUNIOR, O.; CAMPOS, L.L.With the popularization of 3D printing technologies, it is now possible to develop patient specific simulators and various other accessories using this technology in medical physics and dosimetry. This work aims to evaluate the electronic equilibrium of 3D printed phantoms using PLA and ABS filaments compared to PMMA for 137Cs gamma rays using OSL dosimetry. A Landauer microStar ii commercial OSL system were commissioned and it was used nanoDot dosimeters. Phantom plates with 2.5, 3.0 and 5.0 mm thickness were used to obtain electronic equilibrium for 137Cs gamma rays. Measurements were compared with PMMA measurements at standard conditions. Results show that measurements with ABS and PLA thicknesses of 2.5 and 3.0 mm presents dosimetry results within irradiation uncertainty. More accuracy is obtained using 3.0 mm for both PLA and ABS phantoms, with differences in less than 0.5%. It can be concluded that PLA and ABS 3D phantom plates has similar properties of PMMA for 137Cs gamma rays dosimetry and can be used for developing dosimetry accessories for this energy photon beam.Artigo IPEN-doc 26746 Dosimetric characterization of 3D printed for 137Cs gamma rays2019 - ALMEIDA, J.S.; VILLANI, D.; POTIENS, M.P.A.; WILLEGAIGON, J.The aim this paper is characterize materials for 3D printed with different infill percentages for 137Cs gamma rays. The RAISE 3D PRO2 printer was used to print PLA and ABS plates. Using a 137Cs source, the attenuation coefficient was obtained by the transmission method and results compared with PMMA. The readings were performed by a Radcal ionization chamber, model 10X6-6. The results of attenuation coefficients show that the PLA filament demonstrated a equivalent behavior to PMMA. The PLA plates exhibits an increase in radiation transmission when reduces the infilling, and ABS printing achieved same results for all infills.Artigo IPEN-doc 26744 Characterization of ABS + W and ABS + Bi 3D printing filaments attenuation for different photon beams2019 - VILLANI, D.; SAVI, M.; ANDRADE, M.A.B.; CAMPOS, L.L.; POTIENS, M.P.A.3D printing techniques and materials have become widely available in the last couple of decades and remains a hot topic of study as new materials can lead to new applications. This study aims to evaluate the attenuation behaviour of GMASS over photon beams ranging from 29.7 up to 661.7keV, comparing with pure ABS and using theoretical data of pure lead as reference. It was used the transmission method to obtain experimental attenuation coefficients to all materials and theoretical data. HVL and TVL calculations were also performed. Results show that ABS+W has higher attenuation than ABS+Bi and pure ABS. Using the lead theoretical reference data it can be concluded that although ABS+Bi and ABS+W attenuates less than pure lead, the 3D printing filaments can be used to create shielding tolls depending on radiation energy and application.Artigo IPEN-doc 23835 Estudo comparativo de sensibilidade entre os dosímetros fricke xilenol gel e alanina gel2016 - BRESSANE, R.O.; VILLANI, D.; RODRIGUES JUNIOR, O.; CAMPOS, L.L.Fricke Xilenol Gel (FXG) é um dosímetro químico bem conhecido e caracterizado. Neste trabalho, foi adicionada alanina ao FXG a fim de obter melhora na sensibilidade. A comparação entre os dois dosímetros permitiu verificar maior estabilidade no gel devido à presença da alanina e aumento do intervalo de linearidade da resposta óptica: de 1 a 30 Gy para 5 a 50 Gy. Foi possível verificar, também, que a variação de cor das amostras após a irradiação é característica de cada tipo de dosímetro e que a sensibilidade do dosímetro com alanina é maior utilizando-se 0,2 mM de alaranjado de xilenol.Artigo IPEN-doc 22882 Resposta de Microcubos de TLD-100TM a dois feixes de qualidade RQR32016 - NUNES, M.G.; VILLANI, D.; ALMEIDA, S.B.; VIVOLO, V.; YORIYAZ, H.; LOUIS, G.M.J.A resposta de microcubos de TLD-100TM a dois feixes de qualidade RQR 3, definida pela norma IEC-61267, é comparada para que a dependência da resposta do TLD-100TM com a energia efetiva do feixe de radiação X reportada na literatura seja avaliada nessas condições. A reprodutibilidade dos microcubos de TLD-100TM é avaliada através da resposta de um segundo conjunto de dosímetros, obtida em uma segunda leitora, ao feixe implementado no Laboratório de Calibração de Instrumentos do IPEN. A dependência da resposta com a energia efetiva ou o espectro do feixe não foi detectada e a reprodutibilidade das medidas é de 90,2%.Artigo IPEN-doc 23751 Caracterização de dosímetros de Al2O3:C para dosimetria de fótons utilizando a técnica OSL2016 - VILLANI, D.; ALMEIDA, S.B.; CAMPOS, L.L.A dosimetria opticamente estimulada (OSL) tem ganhado destaque em aplicações clínicas e acadêmicas no Brasil. Nesse trabalho, são apresentados resultados da caracterização OSL dos dosímetros de Al2O3:C (TLD-500) fabricados pela Rexon™ Components and TLD Systems em uma leitora RISØ, modelo TL/OSL-DA-20 para dosimetria de feixes de fótons de energias altas. Todos os parâmetros da leitora, e suas variações foram avaliados.Artigo IPEN-doc 23731 Comparative study of different Al2O3:C dosimeters using OSL technique for dosimetry on Volumetric Modulated Arc Radiotherapy Treatment (VMAT)2016 - VILLANI, DANIEL; MANCINI, ANSELMO; HADDAD, CECILIA M.K.; CAMPOS, LETICIA L.In modern radiotherapy, the VMAT technique has become a successful treatment alternative. Due to its complexity, a quality assurance program must be established by evaluating, among other items, the dosimetric factors. This paper aims to compare the performance between the OSL aluminum oxide (Al2O3:C) nanoDot™ dosimeters (Inlight™ system) manufactured by Landauer Inc. and TLD-500 Al2O3:C dosimeters manufactured by Rexon™ for VMAT dosimetry using an anthropomorphic phantom. The results showed that both type of Al2O3:C dosimeters presented good repeatability and agreement between the doses measured and calculated by planning system. However, the need of sophisticated readers to OSL analysis of the TLD-500, turns it less practical for routine usage, comparing to Inlight™ system. Keywords: OSL dosimetry; VMAT; Al2O3:C.