OSVALDO LUIZ DA COSTA

OSVALDO LUIZ DA COSTA

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Design and development of a device for the opening of irradiated aluminum capsules in the IPEN IEA-R1 nuclear reactor
2019 - CASTANHO, FABIO G.; COSTA, OSVALDO L. da
The production of radionuclides in nuclear research reactors is an important activity of national nuclear energy programs. Numerous radionuclides produced include molybdenum-99, iodine-131 and phosphorus-32, widely used in medical procedures. Radionuclides are produced by exposing the target material to a neutron flux in one of the irradiation positions in the core of the nuclear reactor. Before irradiation, the target materials must be contained in sealed capsules, preventing the release of radionuclides that contaminate the nuclear reactor installation. The capsules used in the Nuclear and Energy Research Institute (IPEN) IEA-R1 nuclear reactor are made of aluminum, taking advantage of the following characteristics: low cross section for neutron absorption, radionuclide production from the aluminum alloy of short half-life, good thermal conductivity and possibility of cold sealing of the capsule. This work proposes a new device for opening irradiated aluminum capsules (rabbits), with implement of a better procedure, focusing on operator safety. Ensuring safety during all stages and processes is a preponderant factor when it comes to radioactive materials. The following main deficiencies are identified about the current opening procedure: a) radioactive debris generated by the cutting contaminate the environment of manipulation, increasing the risks of exposure to radiation and the care with the collect and disposal of these debris; b) rotation movement of the capsule during opening may cause damage to the target material and its casing, leading release of radioactive target materials. The new opening device: a) uses the least possible electronic components based on integrated semiconductor circuits, susceptible to radiation; b) contemplates that the insertion and removal of the capsules will be done by telemanipulators; c) modifies the type of cutting performed, from abrasive to cutting wheel blade, allowing minimal generation of small size radioactive debris; d) replaces the rotation of the capsule by a movement in the cutting head, keeping the capsule still, thus reducing the risk of damage to the samples; e) provides greater control, process accuracy and emergency stop, through improved remote operating system. Results of comparative tests showed that the current system produces average 0.3(2) mg of debris per cut, while the proposed system of cutting wheel blade presented a reduction of more than 99 % in the generation of debris. In addition, the immobilization of capsule during the open prevents damage to the radioactive target materials.
Gamma spectrometry of iodine-125 produced in IEA-R1 nuclear reator, using HPGe detector and fixation into epoxy matrix disc
2019 - COSTA, OSVALDO L. da; SOUZA, DAIANE C.B. de; CASTANHO, FABIO G.; FEHER, ANSELMO; MOURA, JOÃO A.; SOUZA, CARLA D. de; OLIVEIRA, HENRIQUE B. de; MADUAR, MARCELO F.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
Few places in the world produce iodine-125. In Brazil, the first production happened in nuclear reactor IEA-R1 located at Nuclear and Energy Research Institute – IPEN. To verify the quality of iodine-125 produced, because contaminants as iodine-126, caesium-134 and caesium-137 among others, may be produced in irradiation process, iodine-125 samples were immobilized into epoxy matrix disc, with the same geometry of a barium-133 reference radioactive source, used to calibrate an HPGe detector. The HPGe detector has a thin carbon composite window, which allows measure the iodine-125 photopeaks, between 27.1 and 35.4 keV.
Análise da região soldada por processo laser em microtubos de titânio por meio de ensaio metalográfico e microdureza
2018 - FEHER, A.; ROSTELATO, M.E.C.M.; ZEITUNI, C.A.; MOURA, J.A.; COSTA, O.L.; SOUZA, C.D.
Um dos materiais utilizados como invólucro de fontes radioativas seladas para aplicações na área da saúde é o titânio. Na construção de fontes radioativas seladas, o radioisótopo é confinado em uma cápsula de metal garantindo que não ocorra sua dispersão no meio externo. O processo de construção desse tipo de fonte requer muitas vezes a soldagem da cápsula, causando alterações das estruturas cristalinas do metal. Essas alterações podem resultar na fragilização da região de solda, ocasionando trincas e consequentemente a inutilização do conjunto. Este trabalho avaliou a possível existência de defeitos de soldagem por meio de ensaio metalográfico e de dureza. Foram realizados ensaios por microscopia óptica e MEV para avaliar a existência de trincas, poros, inclusões, falta de penetração e mordeduras. Foram realizados também ensaios de microdureza Vickers com a finalidade de verificar a variação da dureza entre o metal de base, zona termicamente afetada e zona fundida.
Evaluation of Exhaust System for Gaseous Waste from the Source Production Laboratory for Radiotherapy – IPEN
2017 - SOUZA, D.C.B. de; COSTA, O.L.; FEHER, A.; GERALDO, B.; CARVALHO, V.S.; BARBOSA, N.K.O.; VICENTE, R.; ZEITUNI, C.A.; ROSTELATO, M.E.C.M.
Exhaust systems in fume hood for chemicals and hazardous materials as radioactive substances are of great importance for the protection of the Occupationally Exposed Individual and the environment. They protect against external contam-inations by particulate matter, volatile and against inhalation of radioactive gases. This work intends to evaluate the exhaustion system of the Laboratory of Production of Radioactive Sources at the Nuclear and Energy Research Institute (IPEN).
Brazilian demand for iodine-125 seeds in cancer treatment after a decade of medical procedures
2017 - COSTA, OSVALDO L. da; SOUZA, DAIANE C.B. de; FEHER, ANSELMO; MOURA, JOAO A.; SOUZA, CARLA D.; OLIVEIRA, HENRIQUE B. de; PELEIAS JUNIOR, FERNANDO S.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
A simple and powerful XY-type current monitor for 30 MeV IPEN/CNEN-SP cyclotron
2017 - BARCELLOS, HENRIQUE; MATSUDA, HYLTON; SUMIYA, LUIZ C. do A.; JUNQUEIRA, FERNANDO de C.; COSTA, OSVALDO L. da
A water-cooled XY-type current monitor was designed and built in the Cyclotrons Laboratory of the Nuclear and Energy Research Institute (IPEN). It is a very simple design and easily adaptable to the cyclotron beam lines. Tests were done demonstrating to be an instrument of great assistance in proton beam position along beam transport line and target port. Nowadays the XY-type current monitor has been widely used in 18F-FDG routine productions, employing irradiation system which were originally designed for productions on 18 MeV cyclotron accelerator only, however, applying the XY-type current monitor the target port may be exchanged between the 30 MeV and 18 MeV cyclotrons and the observed results are in perfect agreement with expected.
Surface coating and study of metallic cores for radioactive sources production used in cancer treatment
2016 - ROSTELATO, M.E.C.M.; SOUZA, C.D.; ZEITUNI, C.A.; MATTOS, F.R.; MARQUES, J.R.O.; MOURA, J.A.; FEHER, A.; COSTA, O.L.; SOUZA, D.C.B.; TIEZZI, R.; RODRIGUES, B.T.; KARAM JUNIOR, D.
Developing new and innovative treatments for cancer is an urgent matter. The National Institute of Cancer estimates that Brazil will have 576,000 new cases of the disease in 2015. Our research group is developing new radioactive seeds to be use in radiotherapy procedures since the early 2000’s. We present the surface study and research for two of our major projects: iodine-125 seeds for prostate, brain and eye cancer treatment and iridium-192 for eyecancer treatment.
Proposal for radioactive liquid waste management in brachytherapy sealed sources development laboratory
2014 - SOUZA, C.D.; PELLEIAS JUNIOR, F.S.; ROSTELATO, M.E.C.M.; ZEITUNI, C.A.; BENEGA, M.A.G.; TIEZZI, R.; MATOS, F.R.; RODRIGUES, B.T.; OLIVEIRA, T.B.; FEHER, A.; MOURA, J.A.; COSTA, O.L.
Development and characterization of iridium-192 seeds for brachytherapy treatment of ocular tumors
2014 - PELLEIAS JUNIOR, F.S.; ZEITUNI, C.A.; SOUZA, C.D.; ROSTELATO, M.E.C.M.; MATTOS, F.R.; BENEGA, M.A.G.; RODRIGUES, B.T.; TIEZZI, R.; OLIVEIRA, T.B.; FEHER, A.; MOURA, J.A.; COSTA, O.L.
Evaluation of different reaction methods resulting in the formation of Agl125 for use brachytherapy sources
2014 - SOUZA, C.D.; PELLEIAS JUNIOR, F.S.; ROSTELATO, M.E.C.M.; ZEITUNI, C.A.; BENEGA, M.A.G.; TIEZZI, R.; MATTOS, F.R.; RODRIGUES, B.T.; OLIVEIRA, T.B.; FEHER, A.; MOURA, J.A.; COSTA, O.L.