FABIO GURIAN CASTANHO
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Dissertação IPEN-doc 28772 Projeto e desenvolvimento de um dispositivo para abertura de cápsulas de alumínio irradiadas no reator IEA-R1 do IPEN2021 - CASTANHO, FABIO G.Este trabalho propõe um novo dispositivo para abertura de cápsulas de alumínio irradiadas em reator nuclear, implementando melhorias ao procedimento de abertura, com foco na segurança do operador. As principais deficiências identificadas no dispositivo de abertura atual são: a) os detritos radioativos gerados pelo corte contaminam o ambiente de operação; b) o movimento de rotação da cápsula durante a abertura pode causar danos ao material alvo e ao seu invólucro, levando à liberação de materiais radioativos. O novo dispositivo de abertura foi projetado com as seguintes características: a) facilidade na inserção e remoção das cápsulas por meio de telemanipuladores; b) o tipo de corte foi modificado de abrasivo para lâmina tipo disco de corte, reduzindo a geração de pequenos detritos radioativos; c) a rotação da cápsula foi substituída por um movimento na cabeça de corte, mantendo a cápsula fixa; d) aperfeiçoamento de controle, precisão do processo e, parada de emergência, por meio de sistemas melhorados de operação do dispositivo, com comando remoto em painel de controle. Os testes comparativos mostraram que o sistema atual produz em média 0,3(2) mg de detritos por corte, enquanto o sistema proposto de lâmina tipo disco de corte apresentou uma redução de mais de 99 % na geração de detritos. Além disso, a imobilização da cápsula durante a abertura evita danos aos materiais alvo radioativos.Artigo IPEN-doc 27743 Gamma spectrometry of iodine-125 produced in IEA-R1 nuclear reactor, using HPGe detector and fixation into epoxy matrix disc2021 - COSTA, OSVALDO L. da; SOUZA, DAIANE C.B. de; CASTANHO, FABIO G.; FEHER, ANSELMO; MOURA, JOÃO A.; SOUZA, CARLA D.; OLIVEIRA, HENRIQUE B.; MADUAR, MARCELO F.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.Few places in the world produce iodine-125. In Brazil, the first production was achieved by using the IEA-R1 nuclear reactor located at Nuclear and Energy Research Institute – IPEN. To verify the quality of iodine-125 produced, and the amount of contaminants such as iodine-126, cesium-134 and caesium-137 among others, 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. The method employed here was successful in producing and measurement of iodine-125.Artigo IPEN-doc 26279 Design and development of a device for the opening of irradiated aluminum capsules in the IPEN IEA-R1 nuclear reactor2019 - CASTANHO, FABIO G.; COSTA, OSVALDO L. daThe 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.Artigo IPEN-doc 26206 Gamma spectrometry of iodine-125 produced in IEA-R1 nuclear reator, using HPGe detector and fixation into epoxy matrix disc2019 - 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.