REGINA BECK TICIANELLI

REGINA BECK TICIANELLI

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Análise dos radionuclídeos encontrados na água do reator IEA-R1
2022 - ZAHN, GUILHERME S.; TICIANELLI, REGINA B.; SILVA, PAULO S.C. da; GENEZINI, FREDERICO A.
O reator IEA-R1 é do tipo piscina aberta, construído nos anos 1950. Nos últimos anos, ele opera a 4,5MW por oito horas às segundas, terças e quartas. Em todo dia de operação, duas amostras da água do reator são retiradas, uma antes de o reator ser ligado pela manhã e outra em torno das 16h, próximo ao final as operação. Essas amostras são contadas em um detector HPGe por 1500 s para verificar possíveis problemas com os elementos combustíveis, entre outros. Neste trabalho, os resultados obtidos nessas análises ao longo de alguns meses de 2019 são discutidos em termos dos radionuclídeos encontrados, bem como da dependência da sua atividade com o tempo.
Multi-element contamination in soils from major mining areas in Northeastern of Brazil
2021 - MONTALVAN-OLIVARES, D.M.; SANTANA, C.S.; VELASCO, F.G.; LUZARDO, F.H.M.; ANDRADE, S.F.R.; TICIANELLI, R.B.; ARMELIN, M.J.A.; GENEZINI, F.A.
Mining has become one of the main factors in the global biogeochemical cycle of potentially toxic elements. Therefore, it is considered one of the anthropogenic activities with the greatest negative impact on the environment. These impacts are maximized in semiarid regions, where mining activities can lead to soil degradation and decrease in land productivity. This study aimed to assess the level of contamination in natural, urban, and agricultural soils of three important mining areas, where approximately 80,000 people live, and pollution levels have never been determined before. For this purpose, soil samples were collected around iron, uranium, and vanadium mines, as well as in the main human settlements of the region. The concentrations of 34 elements were determined by instrumental neutron analysis activation (INAA) and inductively coupled plasma optical emission spectrometry (ICP OES) techniques. Pollution indices (CF, EF, mCd, PLI, and REEP) revealed that there is a moderate to heavy level of pollution for 89% of the analyzed elements. Additionally, an extreme contamination level was observed in 78% of the samples, for at least one element. Statistical analyses were performed to identify patterns in the distribution and common sources of pollution. The results suggest that the concentrations for Al, Ba, Hf, Na, Pb, Rb, REE, Ta, Th, U, Zn, and Zr are associated with geogenic causes. However, the influence of anthropogenic sources such as agriculture and mining on the accumulation of these elements in soils should not be disregarded. In contrast, the contents of As, Br, Cd, Co, Cr, Cs, Cu, Fe, K, Mn, Ni, Sc, Ti, and V reflect the direct impact of anthropogenic sources.
Radionuclide analysis of the IEA-R1 pool water
2019 - TICIANELLI, REGINA B.; ZAHN, GUILHERME S.; SILVA, PAULO S.C. da; GENEZINI, FREDERICO A.
IEA-R1 is a 5MW pool-type research reactor built in the late 1950's. In the last years, it operates at 4.5MW for 8h on Mondays, Tuesdays and Wednesdays. In every day of operation, a sample is taken from the pool water both before starting the reactor and at the end of the day and analyzed in an HPGe detector, in order to verify for possible problems with the fuel elements or other issues. In this work, the results obtained in these analyses spanning for some months are discussed regarding the radionuclides frequently identi ed and the dependence of their activities with time.
Evaluation of the uncertainty associated with sample holders in NAA measurements in LAN/IPEN
2019 - ZAHN, G.S.; TICIANELLI, R.B.; SAIKI, M.; GENEZINI, F.A.
In IPEN’s Neutron Activation Laboratory (LAN/IPEN), thin stainless steel sample holders are used for gamma spec-trometry in NAA measurements. This material is very practical, but its chemical composition may be troublesome, as it presents large amounts of elements with intermediate atomic number, with attenuation factors for low-energy gamma-rays that must not be neglected. In this study, count rates obtained using different sample holders were compared. To accomplish that, an Am-241 source, with 59-keV gamma emission, was used so that low-energy gamma attenuation differences can be determined. Moreover, in order to study the energy dependence of these differences, a Ho-166m source was also used. From these results, it was possible to analyze the experimental error associated to the variations between sample holders, with the aim of introducing an addictive term to the uncertainty analysis of comparative Neu-tron Activation Analysis results.
Determinação de impurezas inorgânicas em henna para sobrancelhas para aplicação cosmética
2017 - MARINHEIRO, THAMIRES S.; LANGE, CAMILA N.; FIGUEIREDO, ANA M.G.; TICIANELLI, REGINA B.; JESUS, TATIANE A. de
Alguns cosméticos podem conter impurezas inorgânicas que, dependendo do nível de fração em massa das mesmas na composição do produto, podem causar efeitos nocivos à saúde humana. A henna (Lawsonia inermis) é uma planta, e o pó, obtido de suas folhas secas e maceradas, é comercializado para coloração de cabelos e sobrancelhas. É comum o uso de henna como alternativa às colorações sintéticas, especialmente para os consumidores que preferem produtos cosméticos naturais ou orgânicos, pois estes são tidos como seguros. Entretanto, algumas hennas comerciais são dopadas com materiais que intensificam a cor e diminuem o tempo de aplicação do produto, estes podem ser de origem mineral ou sais iônicos. Estudos do conteúdo de elementos inorgânicos em hennas comercializadas no Brasil são escassos, apesar de o Brasil ser um dos maiores mercados consumidores de cosméticos do mundo e a aplicação de hennas em sobrancelhas ter aumentado nos últimos anos. O objetivo deste estudo foi avaliar a fração em massa de Ba, Cd, Co, Cr, Fe, Ni e Zn em hennas para coloração de sobrancelhas. Hennas de diferentes cores e marcas comercializadas no mercado e aplicadas em salões de cabelereiro foram analisadas. Quatro das 11 amostras analisadas apresentaram valores de fração em massa de bário cerca de 250 vezes maior que o valor preconizado pela agência nacional de vigilância sanitária (ANVISA), fato que pode representar um potencial risco aos usuários deste tipo de produto. As frações em massa de Cd, Co, Cr, Fe, Ni e Zn apresentaram valores abaixo dos limites regulamentados para cosméticos.
Determination of REEs in agricultural soils of pernambuco by the neutron activation technique
2017 - FRANÇA, FERNANDA C.S.S.; TICIANELLI, REGINA B.; MOREIRA, EDSON G.; GENEZINI, FREDERICO A.; ALBUQUERQUE, ADRIANA M. de A.; SILVEIRA, PATRICIA B. da; BARBOSA, JONNAS T. de L.; ALMEIDA, AMANDA C. de; HONORATO, ELIANE V.; HAZIN, CLOVIS A.
The indiscriminate use of phosphate fertilizers causes adverse effects on biota, mainly due to the contaminants present in the rocks used in their manufacture. Among these contaminants, stand out the Rare Earth Elements (REEs) because of the significant increase in the use in several technological areas, such as in vehicle catalysts and also in fertilizer enrichment. In order to evaluate the levels of La, Sm, Nd, Yb and Lu by the Instrumental Neutron Activation Analysis (INAA), the present study aims to survey the ETRs in agricultural soils in Pernambuco/Brazil. For this study, 120 soil samples with a depth of 20 cm were collected in the main vegetable producing regions of the Metropolitan Region of Recife (RMR), evaluating organic and conventional crops with and without influenced by automotive vehicles. The results obtained when compared to the Netherlands reference values defined by the National Institute of Health and Environment (RIVM). The results were higher in all points for La (35 mg.kg-¹ at 85 mg.kg-¹) Yb, (4 mg.kg-¹ at 11 mg.kg-¹) and Lu (0.3 mg.kg-¹ at 0.7 mg.kg-¹ at 4 mg.kg-¹). For Nd (9 mg.kg-¹ at 137 mg.kg-¹) the concentrations were above the values reported by RIVM in 4 points. Comparing the types of crops evaluated with the literature, the results are found was above for all elements analyzed. It may be related to the increase in the use of phosphate fertilizers. However, in environments using smaller amounts of additives, the results were also significant and the more detailed studies are needed to evaluate other possible contamination pathways.
Evaluation of the uncertainty associated with sample holders in NAA measurements in LAN/IPEN
2017 - ZAHN, GUILHERME S.; TICIANELLI, REGINA B.; SAIKI, MITIKO; GENEZINI, FREDERICO A.
In IPEN’s Neutron Activation Laboratory (LAN/IPEN), thin stainless steel sample holders are used for gamma spectrometry in NAA measurements. This material is very practical, but its chemical composition may be troublesome, as it presents large amounts of elements with intermediate atomic number, with attenuation factors for low-energy gamma-rays that must not be neglected. In this study, count rates obtained using different sample holders were compared. To accomplish that, an Am-241 source, with 59-keV gamma emission, was used so that low-energy gamma attenuation differences can be determined. Moreover, in order to study the energy dependence of these differences, a Ho-166m source was also used. From these results, it was possible to analyze the experimental error associated to the variations between sample holders, with the aim of introducing an addictive term to the uncertainty analysis of comparative Neutron Activation Analysis results.
Long-term performance assessment of hpge detectors used in the neutron activation analysis (LAN) of IPEN-CNEN/SP (Brazil)
2016 - ZAHN, GUILHERME S.; GENEZINI, FREDERICO A.; TICIANELLI, REGINA B.; SAIKI, MITIKO
In nuclear spectroscopy measurements, the performance of the radiation detectors employed is a key issue in the final results; moreover, in comparative measurements, the results depend on the stability of the detector between measurements, so that the detector’s efficiency can be effectively ruled out of the equation. Due to the relevance of the detectors' performances, LAN-IPEN have been performing daily verification measurements in its operational detectors since 1999; this verification consists in the measurement of composite 57+60Co sources, in which the position, resolution and CPS (counts per second) for the 122 keV peak of 57Co and the 1332 keV peak of 60Co are registered, along with the date and time of the measurement. In this work, verification data for 11 HPGe detectors from two different makers and three different intrinsic configurations were analyzed in respect to the efficiency stability (determined by the arbitrary efficiency calculated by correcting the CPS for the isotope's decay) and resolution for both peaks, as well as the ratio between the efficiencies for 122 keV and 1332 keV. The results allow a discussion about the stability of these parameters over time (in some cases, more than 15 years), their sensitivity to imminent detector failures and their performance after a failure has been corrected; moreover, the results show a clear correlation between the maker or configuration and the long-term performance of the detector.
Long-term performance assessment of HPGE detectors used in the neutron activation analysis laboratory of IPEN-CNEN/SP (Brazil)
2017 - ZAHN, G.S.; GENEZINI, F.A.; TICIANELLI, R.B.; SAIKI, M.
In this work, verification data for 11 HPGe detectors from two different manufacturers and three different intrinsic configurations were analyzed in respect to the stability of both the efficiency and resolution for the 122 keV peak from 57Co and the 1332 keV peak from 60Co. The results allow a discussion about the stability of these parameters over time (in some cases, almost 15 years), their sensitivity to imminent detector failures and their performance after a failure has been corrected; moreover, the results show a clear correlation between the manufacturer or configuration and the long-term performance of the detector.
A Brazilian coal fly ash as a potential source of rare earth elements
2017 - LANGE, CAMILA N.; CAMARGO, IARA M.C.; FIGUEIREDO, ANA MARIA G.M.; CASTRO, LILIANA; VASCONCELLOS, MARINA B.A.; TICIANELLI, REGINA B.
Rare earth elements (REEs) have several applications and their market demands have increased. Recently, coal fly ash (CFA) has been considered as a source of these elements. The purpose of this study was to evaluate the REEs content in a CFA from a Brazilian coal power plant by instrumental neutron analysis, to classify it according to commercial purposes and to assess the weathering impact in the REEs content, since it is held in fields nearby the power plant. The results pointed no significant REEs leachability and indicated this CFA as a promising REEs source.