CELIA MARINA NAPOLITANO

CELIA MARINA NAPOLITANO

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Online electron beam monitoring with a diode-based dosimetry system in routine quality control
2023 - GONCALVES, JOSEMARY A.C.; MANGIAROTTI, ALESSIO; SOMESSARI, ELIZABETH S.R.; NAPOLITANO, CELIA M.; BUENO, CARMEN C.
Development of an irradiation system for production of gaseous radioisotopes and of a tomographic 2-D gamma scanning for industrial process troubleshooting in Brazil
2022 - CARDOZO, NELSON X.; HARAGUCHI, MARCIO I.; KIM, HAE Y.; SOMESSARI, SAMIR L.; FEHER, ANSELMO; NAPOLITANO, CELIA M.; CALVO, WILSON A.P.
Radioisotopes as radiotracers are used in analytical procedures to obtain qualitative and quantitative data systems, in physical and physicochemical studies transfers, and troubleshooting of industrial process plants in chemical and petrochemical companies. In the production of gaseous radioisotopes used as tracers in industrial process measurements, argon-41 (41Ar) and krypton-79 (79Kr) stand out because each has low reactivity with other chemical elements. 41Ar is a transmitter range with high-energy (1.29 MeV) and a high percentage of this energy transformation (99.1%), resulting in relatively small quantities required in relation to the other, for an efficient detection, even in large thicknesses components. In this sense, the aim of this study is to develop an irradiation system for gaseous radioisotope production in continuous scale, applied in industrial applications of emission tomography and flow measurement. The irradiation system may produce 41Ar with activity of 7.4×1011 Bq (20 Ci) per irradiation cycle, through the Reactor IEA-R1 with 4.5 MW and average thermal neutron flux of 4.71×1013 ncm−2s−1 to meet an existing demand in NDT and inspections companies, and even needed by the Radiation Technology Centre, at IPEN/CNEN. The irradiation system consists of an aluminium irradiation capsule, transfer lines, needle valves, ringed connections, quick connectors, manometer, vacuum system, dewar, lead shielding, storage and transport cylinders, among other components. The irradiation system was approved in the leakage and stability tests (bubble test, pressurization, evacuation and with leak detector equipment. In the experimental production obtaining 1.07×1011 Bq (2.9 Ci) of 41Ar, alanine dosimeters were distributed into various components of the irradiation system. In addition, exposure rates were determined in the lead shielding wall, in which the liquefied radioactive gas was concentrated, and in the storage and transport cylinders after 41Ar was transferred by the portable radiation meter. However, gamma scanning is a nuclear inspection technique widely used to troubleshoot industrial equipment in refineries and petrochemicals plants such as distillation columns and reactors. A sealed radiation source and detector move along the equipment, and the intensity readouts generate the density profile of the equipment. The result of gamma scan still consists of a simple 1-D density plot. In this work, we also present the tomographic gamma scanning that, using image reconstruction techniques, shows the result as a 2-D image of density distribution. Clearly, an image reveals more features of the equipment than a 1-D graph and many problems that could not be troubleshooted using the conventional technique can now be solved with this imaging technique. We use ART (Algebraic Reconstruction Technique) intercalated with total variation minimization filter. The use of total variation minimization leads to compressive sensing tomography, allowing to obtain good quality reconstruction from few irradiation data. We simulated the reconstruction of different density distributions. We applied the new technique to data obtained by irradiating with gamma rays phantoms that emulate industrial equipment. Finally, we present the result obtained by applying the innovative technique to real operating distillation column.
Transit dose measurements using alanine and diode-based dosimeters
2021 - GONCALVES, J.A.C.; SOMESSARI, E.S.R.; NAPOLITANO, C.M.; SOMESSARI, S.L.; BUENO, C.C.
Development of a shielding device for radiotherapy of breast cancer-bearing mice
2020 - SILVA, C.R.; PEREIRA, S.T.; NAPOLITANO, C.M.; SOMESSARI, E.S.R.; RIBEIRO, M.S.
Breast cancer is the fifth most common cause of death worldwide. Currently, one of the standard treatments for breast cancer is radiation therapy (RT). On the other hand, mouse models have been used in pre-clinical studies for breast cancer RT, requiring dedicated shielding to exposure the breast region. In this work, we considered the values of the lead attenuation coefficient and the material tenth reducing layer for 60Co gamma radiation and developed a lead shielding device for breast cancer-bearing mice to be exposed to localized breast RT. Five-kg of lead were heated to of 340ºC and inserted into an aluminum mold previously adjusted to the dimensions of the device. After solidification, the device was shaped into a cylinder with dimension of 14 x 15 x 7 cm (height x width x thickness, respectively). A round cut-out for breast exposure of 1 cm in diameter was made at 5 cm from the basis of the device. For shielding device validation, we performed calibrations to establish a dose of 10 Gy to the target volume. Fifteen CaSO4:Dy thermoluminescent dosimeters were distributed inside the conical tube to mimic the mouse position inside the shielding. The shielding device was placed at a fixed distance of 10 cm from the target for optimal exposure time. After irradiation, the dosimeters were read using a thermoluminescent reader. According to our results, we were able to develop a body-shielding device that assured the required dose for RT of breast cancer in mice.
Development of an irradiation system for radioisotope production applied to industrial process tomography
2016 - CARDOZO, NELSON X.; OMI, NELSON M.; AMBIEL, JOSE J.; FEHER, ANSELMO; NAPOLITANO, CELIA M.; SOMESSARI, SAMIR L.; CALVO, WILSON A.P.
Among the various applications of radioisotopes, the use of radiotracers is considered the most important in diagnosing operation and troubleshooting of industrial process plants in chemical and petrochemical companies. The radiotracers are used in analytical procedures to obtain qualitative and quantitative data systems, in physical and physicochemical studies transfers. In the production of gaseous radioisotopes used as tracers in industrial process measurements, argon-41 (41Ar) and krypton-79 (79Kr) have low reactivity with other chemical elements. 41Ar is a transmitter range with high-energy (1.29MeV) and a high percentage of this energy transformation (99.1%), resulting in relatively small quantities required in relation to the other, for an efficient detection, even in large thicknesses components. Nowadays, the production of gaseous radioisotopes in nuclear research reactors is performed in small quantities (batches), through quartz ampoules containing natural gas 40Ar or 78Kr. In this sense, the aim of this study is to develop an irradiation system for gaseous radioisotope production in continuous scale, applied in industrial applications of emission tomography and flow measurement. The irradiation system may produce 41Ar with activity of 7.4x1011Bq (20Ci) per irradiation cycle, through the Reactor IEA-R1 with 4.5MW and average thermal neutron flux of 4.71x1013 ncm-2s-1 to meet an existing demand in NDT and inspections companies, and even needed by the Radiation Technology Centre, at IPEN/CNEN-SP. The irradiation system consists of an aluminium irradiation capsule, transfer lines, needle valves, stripy connections, quick connectors, manometer, vacuum system, dewar, lead shielding, storage and transport cylinders, among other components. The irradiation system was approved in the leakage and stability tests (bubble test, pressurization, evacuation and with leak detector equipment SPECTRON 600 T). In the experimental production, alanine dosimeters were distributed into various components of the irradiation system, obtaining 1.07x1011Bq (2.9Ci) of 41Ar. In addition, exposure rates were determined in the lead shielding wall, in which the liquefied radioactive gas was concentrated, and in the storage and transport cylinders after 41Ar was transferred, by the portable radiation meter Teletector ® Probe 6150 AD-t/H.
Preliminary studies on the development of an automated irradiation system for production of gaseous radioisotopes applied in industrial processes
2019 - DOURADO, NELSON X.; OMI, NELSON M.; SOMESSARI, SAMIR L.; GENEZINI, FREDERICO A.; FEHER, ANSELMO; NAPOLITANO, CELIA M.; AMBIEL, JOSE J.; CALVO, WILSON A.P.
The purpose of the present study is to demonstrate how it will be enhanced an Irradiation System (IS) developed with national technology to produce gaseous radioisotopes, by means of the components automation, to avoid the radiation exposure rate to operators of the system, following the ALARA principle (As Low As Reasonably Achievable). Argon-41 (41Ar) and krypton-79 (79Kr) can be produced in continuous scale, gaseous radioisotopes used as radiotracers in industrial process measurements and it can be used in analytical procedures to obtain qualitative and quantitative data systems or in physical and physicochemical studies transfers. The production occurs into the IS, installed in the pool hall of a nuclear research reactor in which the irradiation capsule is positioned near the reactor core containing the isotope gaseous pressurized (40Ar or 78Kr), by (n,γ) reaction and generate the radioisotopes. After the irradiation, the gaseous radioisotope is transferred to the system and, posteriorly, to the storage and transport cylinders, that will be used in an industrial plant. In the first experimental production, was obtained 1.07x1011 Bq (2.9 Ci) of 41Ar distributed in two storage and transport cylinders, operating the IEA-R1 Research Reactor with 4.5 MW and average thermal neutron flux of 4.71x1013 n.cm-2.s-1. However, the system has capacity to five storage and transport cylinders and the estimated maximum activity to be obtained is 7.4x1011 Bq (20 Ci) per irradiation cycle. In this sense, the automation will be based in studies of the production process in the system and the use of Programmable Logic Controllers (PLC), and supervisory software allowing a remote control and consequently better security conditions.
Irradiation system for production of gaseous radioisotopes used as tracers in industrial process measurements
2018 - CARDOZO, N.X.; OMI, N.M.; AMBIEL, J.J.; FEHER, A.; NAPOLITANO, C.M.; SOMESSARI, S.L.; CALVO, W.A.P.
The use of radioisotopes as radiotracers is considered the most important in diagnosing operation and troubleshooting of industrial process plants in chemical and petrochemical companies. They are used in analytical procedures to obtain qualitative and quantitative data systems, in physical and physicochemical studies transfers. In the production of gaseous radioisotopes used as tracers in industrial process measurements, argon-41 (41Ar) and krypton-79 (79Kr) stand out because each has low reactivity with other chemical elements. 41Ar is a transmitter range with high-energy (1.29 MeV) and a high percentage of this energy transformation (99.1%), resulting in relatively small quantities required in relation to the other, for an efficient detection, even in large thicknesses components. Nowadays, the production of gaseous radioisotopes in nuclear research reactors is performed in small quantities (batches), through quartz ampoules containing natural gas 40Ar or 78Kr. In this sense, the aim of this study is to develop an irradiation system for gaseous radioisotope production in continuous scale, applied in industrial applications of emission tomography and flow measurement. The irradiation system may produce 41Ar with activity of 7.4×1011 Bq (20 Ci) per irradiation cycle, through the Reactor IEA-R1 with 4.5MW and average thermal neutron flux of 4.71×1013 ncm−2s−1 to meet an existing demand in NDT and inspections companies, and even needed by the Radiation Technology Centre, at IPEN/CNEN-SP. The irradiation system consists of an aluminium irradiation capsule, transfer lines, needle valves, ringed connections, quick connectors, manometer, vacuum system, dewar, lead shielding, storage and transport cylinders, among other components. The irradiation system was approved in the leakage and stability tests (bubble test, pressurization, evacuation and with leak detector equipment SPECTRON 600 T). In the experimental production obtaining 1.07×1011 Bq (2.9 Ci) of 41Ar, alanine dosimeters were distributed into various components of the irradiation system. In addition, exposure rates were determined in the lead shielding wall, in which the liquefied radioactive gas was concentrated, and in the storage and transport cylinders after 41Ar was transferred by the portable radiation meter Teletector® Probe 6150 AD-t/H.
Gamma radiation effects in packaging for sterilization of health products and their constituents paper and plastic film
2018 - PORTO, KARINA M.B.G.; NAPOLITANO, CELIA M.; BORRELY, SUELI I.
The integrity of materials containing packaging (natural or synthetic polymers) is essential to keep the aseptic condition of commercialized products (health care products, food and pharmaceuticals). The objective of this paper was to study gamma radiation effects (25 kGy, 40 kGy and 50 kGy) on the main properties of paper and multilayer films (polyester and polyethylene). Paper and multilayer films are components of packaging (pouches) for radiation sterilization containing medical equipment or products. Paper was the more radiation sensitive among the studied materials and radiation effects were more pronounced at brightness, pH, tearing resistance, bursting strength and tensile strength. Concerning plastic film, no pinholes were induced by radiation and the effects on the tensile strength were not significant. Although the seal strength packaging (pouches) decreased according to increasing dose, the sealing integrity was preserved.
A dosimetric survey of the DC1500/25/04 electron beam plant installed at IPEN-CNEN/SP
2016 - SOMESSARI, SAMIR L.; KUNTZ, FLORENT; SILVEIRA, CARLOS; BUENO, CARMEN C.; NAPOLITANO, CELIA M.; CALVO, WILSON A.P.; GONÇALVES, JOSEMARY A.C.
In this work we describe a dosimetric survey of the DC1500/25/04 electron beam accelerator installed in the Intense Sources of Radiation Laboratory at IPEN/CNEN-SP. As this accelerator has been used for innumerable applications in radiation processing, product surface and internal doses must be targeted and controlled via operational qualification such as beam energy, beam current, scan width and conveyor speed. The qualification was carried out in order to observe the current performances of the irradiation plant using Alanine (ESR) and CTA (UV Spectrophotometry) dosimeters. Energy (Electron penetration in material) calculations, scanning width/length, homogeneity and irradiation uniformity were evaluated according to ISO/ASTM 51649 and ISO11137-3, as well as process uncertainty establishment.
Influência da temperatura na resposta de dosímetros de polimetilmetacrilato (PMMA)
2005 - FERREIRA, DANILO C.; NAPOLITANO, CELIA M.; TOBIAS, CARMEN C.B.