JOAO PEDRO DE OLIVEIRA FLORES
3 resultados
Resultados de Busca
Agora exibindo 1 - 3 de 3
Artigo IPEN-doc 30602 Re-characterization of pneumatic station irradiation position of IEA-R1 reactor for use in k0 - INAA method2024 - FLORES, J.P.O.; SEMMLER, R.; DIAS, M.S.; KOSKINAS, M.F.; MOREIRA, D.S.; YAMAZAKI, I.M.; SILVA, P.S.C.; MAIHARA, V.A.Artigo IPEN-doc 26150 Calibration of the short irradiation facility for K0 − NAA implementation at the IEA-R1 Reactor2019 - OLIVEIRA, J.P.; SILVA, P.S.C.; SEMMLER, R.The short irradiation facility of the IEA-R1 nuclear research reactor at IPEN, S~ao Paulo, Brazil, has been used for short irradiation of samples for the purpose of determining the concentration of elements of these samples through the use of the instrumental neutron activation analysis technique. With the aim of implementing the k0-NAA method at the Neutron Activation Analysis Laboratory (LAN), the reactor parameters and f were obtained using the bare triple method. In this method, a set of three neutron ux monitors were irradiated without Cd-cover. The e ciency curve of the gamma-ray spectrometer used were determined by measuring calibrated radioactive sources at the usually utilized counting geometries. The results obtained for the parameters and f were respectively 0:0384 0:0016 and 35:67 0:26. The obtained value of f shows that the neutrons in the irradiation position are well thermalized, in other words, the value of f, means that thermal neutron ux is 35 times higher than epithermal neutron ux. It means that this irradiation position is well thermalized. The variation of these parameters was studied with time and the reproducibility was veri ed.Artigo IPEN-doc 25002 Preparación de muestras del médio ambiente para análisis por médio de técnicas cromatograficas2017 - VEGA, O.; LOPES, P.R.; AMARAL, P.O.; GONSCHOROWSKI, G.; OLIVEIRA, J.P.; FABBRO, R.; MESQUITA, K.A.; GIMENEZ, M.P.; REDIGOLO, M.Este artículo explora la ciencia de la preparación de muestras para matrices sólidas, líquidos y gases, utilizados en el laboratorio del Centro de Química y Medio Ambiente del IPEN. Extracción de neonicotinoides del agua por LLE (Liquid-Liquid Extraction), extracción de hidrocarburos aromáticos policíclicos (PAHs) del agua atraves de DLLME (Dispersive liquid - liquid micro extraction) y el uso de extracción en fase sólida SPE (Solid Phase Extraction) para el análisis de hormonas en agua son descritos. Limites de detección que utilizan estas técnicas son descritas en este trabajo.