BIANCA GERALDO
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Resumo IPEN-doc 30976 Determination of Ni-63 on filters cartridges of water purification system of IPEN Research Reactor IEA-R12023 - SILVA, DEREK; GERALDO, BIANCA; VICENTE, ROBERTO; MARUMO, JULIO T.The Nuclear and Energy Research Institute (IPEN - CNEN/SP), has an open pool-type reactor that generates radioactive waste from the purification system of the cooling water, as resins, charcoal and filter cartridges. These wastes must be properly characterized before their treatment. The objective of this work is to describe one step of the characterization which is the radiochemical analysis of Ni-63 present in the filter cartridges. Ni-93 is one of the main radionuclides present. Based on the chemical recovery results obtained, it is possible to state that the method is valid for the determination of 63 Ni.Livro IPEN-doc 28394 Essays on nuclear energy and radioactive waste management2021 - TESSARO, ANA P.G.; GERALDO, BIANCA; SOUZA, DAIANE C.B. de; ROMERO, FERNANDA; BISURI, INDRANIL; MARUMO, JULIO T.; CHEBERLE, LUAN T.V.; SACHDEVA, MAHIMA; ROSA, MYCHELLE M.L.; ROLINDO, NATALIE C.; SMITH, RICARDO B.; VICENTE, ROBERTO; SALVETTI, TEREZA C.Artigo IPEN-doc 27429 Radioanalytical methods for sequential analysis of actinide isotopes in activated carbon filter‑bed waste2020 - GERALDO, BIANCA; ARAUJO, LEANDRO G. de; VICENTE, ROBERTO; TADDEI, MARIA H.T.; CHEBERLE, SANDRA M.; MARUMO, JULIO T.In this work, we compare methods for the sequential determination of U and the transuranium elements Np, Pu, Am, and Cm. The chemical yield, the time spent in the analysis, the amount of secondary waste, and the costs of each method are the aspects of interest. Two methods were compared: extraction chromatography (EC) and ion exchange plus extraction chromatography (IE + EC). The chemical yields of (EC) and (IE + EC) were similar for all radionuclides. The (EC) method is the more effective with respect to time of analysis, the amount of secondary waste and costs.Resumo IPEN-doc 27082 Radiochemical methodology applied to determination of gamma emitting radionuclides in waste samples from IEA-R1 reactor2017 - GERALDO, BIANCA; VICENTE, ROBERTO; GOES, MARCOS M.; MARUMO, JULIO T.Artigo IPEN-doc 27080 Radiochemical method for characterization of the filter cartridges from the IEA-R1 reactor2016 - GERALDO, BIANCA; VICENTE, ROBERTO; FERREIRA, ROBSON J.; MADUAR, MARCELO F.; GOES, MARCOS M.; MARUMO, JULIO T.The filter cartridges used in water purification system of the IEA-R1 research reactor become radioactive waste after the end of their useful life. The characterization of this waste is one step in their management, which aims at identifying and quantifying the radionuclides present, including those known as "difficult to measure" (DTM) radionuclides. Wastes from nuclear reactors contain fission and activation products and transuranic elements, only few of them emitting gamma radiation measurable by simple gamma spectrometry methods. In routine waste management activities, the concentrations of the DTM can only be estimated by indirect methods such as scaling factors. The method of the scaling factors uses empirically determined proportions between the concentrations of DTM radionuclides and that of easily measurable gamma emitters called key nuclides (KN), to calculate DTM concentrations. Determining the scaling factors for the filter cartridges is a hard task when the number of samples is large, not only because the preparation of samples is difficult but also because the number of radionuclides to analyze is large. If it can be demonstrated that DTM and KN are both distributed evenly in the filters, less samples from each filter are necessary, reducing lab work. The aim of this paper is to present the results of the assessment of homogeneity along the filter cartridges by gamma spectrometry of chemically reduced samples. Five thin slices of five filters were burnt and the ashes quantitatively dissolved and the activity concentration of the solutions determined by gamma spectrometry.Artigo IPEN-doc 26681 Radiochemical characterization of spent filter cartridges from the primary circuit of a research reactor2019 - GERALDO, BIANCA; ARAUJO, LEANDRO G. de; TADDEI, MARIA H.T.; FERREIRA, MARCELO T.; MADUAR, MARCELO F.; VICENTE, ROBERTO; MARUMO, JULIO T.Radiochemical-based analyses have been used for the characterization of radioactive waste. Nevertheless, the determination of alpha, beta and gamma emitters by radiochemical analysis of spent cartridge filters from a swimming-pool type reactor has not been previously addressed. This work aims at identifying and quantifying the radionuclides present in this waste, including the difficult to measure radionuclides. The distribution of the radionuclides in the filter was investigated by the determination of gamma-emitting nuclides and the z-score of the measured activity concentrations. The results indicated that all the filters are homogeneous, meeting the homogeneity criteria recommended by the International Atomic Energy Agency.Artigo IPEN-doc 24425 Radioactive waste management Goiânia - São Paulo: 30 years later2017 - SOUZA, D.C.B. de; GERALDO, B.; TESSARO, A.P.G.; ROSTELATO, M.E.C.M.; MARUMO, J.T.; CARVALHO, V.S.; BARBOSA, N.K.O.; VICENTE, R.Considered the largest urban radiological accident in the world, the accident in Goiânia with Cesium-137 resulted in the death of four people and injuries in another 49, besides measurable levels of internal or exter-nal contamination in 129. The accident generated also environmental contamination and thousands of tons of radioactive waste that resulted from the response activities. The accident occurred as a result of the disman-tling of an equipment of radiotherapy by employees of a junkyard. Before the accident was identified, con-taminated materials were sent to recycling companies in the state of São Paulo. The objective of this work was to report the existence of waste from Goiânia accident in the state of São Paulo and to check the estimat-ed activities at the time of the waste conditioning by measuring the current dose rates in waste packages, allowing a refinement of previously applied calculations.Artigo IPEN-doc 24097 Production of a square geometry americium standard source for use with photodiodes2017 - COSTA, PRISCILA; GERALDO, BIANCA; RAELE, MARCUS P.; MARUMO, JULIO T.; VICENTE, ROBERTO; ZAHN, GUILHERME S.; GENEZINI, FREDERICO A.In the development of a thermal neutron detector using a square photodiode and a thin boron film, a radioactive calibration source with the same geometry was needed. An americium-243 standard source was produced by electrodeposition aiming at the calibration of a PIN-type silicon photodiode with a detection area of 10 x 10 mm2. To produce the samples two tests were performed. In the first test, a square stainless steel plate (10 x 10 mm2) was fixed on the surface of the conventional plate, which was removed after deposition. To reduce the loss of activity of the source, in the second test nail polish was applied on the silver plate leaving only an area of 10 x 10 mm2 without varnish coating. Once the electrodeposition process was completed, the activity concentration measurement was performed by alpha particle spectrometry. The first method presented a lower activity when compared to the total activity of Am-243 added initially. For the second method, the total activity was concetrated in the exposed square region (without nail polish).The results showed that it is possible to obtain a square geometry source; furthermore, the surrounding nail polish was not contaminated by 243Am. The comparison of these two approaches indicated that the second method was more efficient as it was possible to concentrate all the americium activity in the delimitated square area.Artigo IPEN-doc 21018 Characterization of filter cartridges from the IEA-R1 reactor by radiometric methods2015 - GERALDO, BIANCA; VICENTE, ROBERTO; FERREIRA, ROBSON J.; GOES, MARCOS M.; MARUMO, JULIO T.Artigo IPEN-doc 19261 Utilization of radioanalytical methods for the determination of isotopes of U, Pu and Am in activated charcoal from IEA-R1 reactor2013 - GERALDO, BIANCA; TADDEI, MARIA H.T.; MARUMO, JULIO T.