MARCIA PIRES DE CAMPOS

MARCIA PIRES DE CAMPOS

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Radiological evaluation of bricks made with NORM residue
2019 - CAMPOS, MARCIA P. de; NISTI, MARCELO B.; PASCHOALIN FILHO, JOAO A.; MAZZILLI, BARBARA P.
Radon concentrations on the nuclear and radioactive instalations of nuclear reactor center – CRPQ/IPEN
2019 - SILVA, PAULO S.C. da; CAMPOS, MARCIA P. de; REIS, GUILHERME de L.
Nuclear and radioactive workers are normally exposed to dose resulting from their day by day activities. Besides that, the ubiquitous radon distribution can also contribute for the exposure rates. The radionuclide 222Rn is a noble gas belonging to the uranium series and its indoor concentration in the air depend on exhalation from surrounding soil and on exhalation from building materials. Radon emanating from porous building materials may achieve large relevance in areas with high uranium concentrations and areas with limited ventilation. The objective of this study was to evaluate the 222Rn concentrations in the radiochemistry and radiometric laboratories and in the reactor nuclear building of the Nuclear Reactor Center (CERPq) located in the Nuclear and Energy Research Institute (IPEN). Measurements were done by using a Radon Gas Monitor, model RAD7, produced by Durridge Company equipped with a solid state alpha detector and a passive method, with SSNTDs placed within small diffusion chambers, as detectors square pieces (2.5 cm × 2.5 cm) of CR 39 foils were used. The CR 39 detectors were etched in KOH 30% solution at 80 °C for 5.5 h in a constant temperature bath. After etching, the detectors were washed, dried, and scanned under a Carl Zeiss microscope to obtain the track density measurements. The activity concentrations varied from 52 to 103 Bq m 3 for the measured areas in CERPq. These values are in accordance with what is stablished by the World Health Organization for safe environments of 100 Bq m 3.
A comparison of analytical methods for screening gross alpha and beta radioactivity in water by liquid scintillation counting and gas flow proportional counting
2015 - NISTI, M.B.; FERREIRA, A.O.; CAMPOS, M.P.; SAUEIA, C.H.R.; MAZZILLI, B.P.
Radon exposure at a radioactive waste storage facility
2014 - MANOCCHI, F.H.; CAMPOS, M.P.; DELLAMANO, J.C.; SILVA, G.S.
The Waste Management Department of Nuclear and Energy Research Institute (IPEN) is responsible for the safety management of the waste generated at all internal research centers and that of other waste producers such as industry, medical facilities, and universities in Brazil. These waste materials, after treatment, are placed in an interim storage facility. Among them are 226Ra needles used in radiotherapy, siliceous cake arising from conversion processes, and several other classes of waste from the nuclear fuel cycle, which contain Ra-226 producing 222Rn gas daughter. In order to estimate the effective dose for workers due to radon inhalation, the radon concentration at the storage facility has been assessed within this study. Radon measurements have been carried out through the passive method with solid-state nuclear track detectors (CR-39) over a period of nine months, changing detectors every month in order to determine the long-term average levels of indoor radon concentrations. The radon concentration results, covering the period from June 2012 to March 2013, varied from 0.55 ± 0.05 to 5.19 ± 0.45 kBq m−3 . The effective dose due to 222Rn inhalation was further assessed following ICRP Publication 65.
High strength phosphogypsum and its use as a building material
2007 - KANNO, WELLINGTON M.; ROSSETTO, HEBERT L.; SOUZA, MILTON F. de; MADUAR, MARCELO F.; CAMPOS, MARCIA P. de; MAZZILLI, BARBARA P.
A new process (patent applied) that works equally well with both plaster of mineral gypsum and phosphogypsum for the preparation of gypsum components, UCOS, has been developed. The process consists of the following steps: humidification of plaster by fine water droplets, uni-axial compression, hydration reaction and drying. Strong hydrogen bonds develop among the crystals together with adhesion provided by confined water that accounts for nearly 70% of the adhesion forces. By reducing the plaster to water ratio to close the minimum necessary, new features are generated. An experimental house has been constructed, in which walls and ceilings have been built of gypsum and phosphogypsum. Since phosphogypsum potentially contain radioactive elements, the application of an activity concentration index to the phosphogypsum employed in the building was carried out.
Radiological impact of the application of phosphogypsum in civil construction: an overview of Brazilian studies
2013 - CAMPOS, MARCIA P.; NISTI, MARCELO B.; MADUAR, MARCELO F.; MAZZILLI, BARBARA
Estudo da exalação de Rn-222 em fosfogesso por meio da técnica de adsorção em carvão ativado
2011 - NISTI, MARCELO B.; CAMPOS, MARCIA P. de
Toronio no ar .Avaliacao da dose ocupacional
1999 - CAMPOS, MARCIA P. de