SABINE NEUSATZ GUILHEN

SABINE NEUSATZ GUILHEN

(Fonte: Lattes)

Resumo

Possui graduação em Química com atribuições Tecnológicas e Biotecnológicas pelo Instituto de Química da Universidade de São Paulo (2005), mestrado (2009) e doutorado (2018) em Tecnologia Nuclear (Materiais) pelo Instituto de Pesquisas Energéticas e Nucleares (IPEN), Universidade de São Paulo. Tem experiência em Química Analítica com ênfase em Análise de Traços, atuando principalmente no desenvolvimento de métodos analíticos empregando técnicas espectrofotométricas (AAS, ICP OES e ICP-MS) para caracterização de amostras ambientais, arqueológicas, biológicas, forenses e nucleares. Atualmente, ocupa o cargo de Tecnologista em "Caracterização Química" no Centro de Química e Meio Ambiente (CQMA) do IPEN (CNEN/SP), onde desempenha atividades de pesquisa e desenvolvimento tecnológico em atendimento às demandas institucionais ligadas ao Ciclo do Combustível Nuclear e aos Programas de Pesquisa de caráter multidisciplinar, em apoio a projetos de Inovação Tecnológica e ao Programa de Pós-Graduação do IPEN/USP. Além disso, atua na geração de produtos tecnológicos e no desenvolvimento de materiais adsorventes de baixo custo e alto valor agregado visando o aproveitamento de materiais e resíduos naturais e/ou renováveis no tratamento de efluentes e rejeitos. (Texto extraído do Currículo Lattes em 4 maio 2023)

Lattes

Página do item completo

Resultados de Busca

Agora exibindo 1 - 7 de 7

Direct determination of aluminum in low-enriched UAlx targets (UAlx-Al) by ICP OES
2021 - GUILHEN, S.N.; SOUZA, A.L.; COTRIM, M.E.B.; PIRES, M.A.F.
The production of molybdenum-99 (99Mo) using low-enriched uranium targets (< 20% 235U) dispersed in aluminum (UAlx) is a very promising strategy towards the independence in 99Mo local production. A thorough control must be performed to ensure that these targets meet the regulatory requirements to achieve the expected efficiency in the reactor. The determination of the targets’ composition is of high interest, because the distribution of Al in different phases may have an impact on the U concentration. Among the techniques used for this purpose, inductively coupled plasma optical emission spectrometry (ICP OES) stands out because of its high sensitivity and precision, allowing for simultaneous determination of several elements in a variety of samples and matrices. However, because U exhibits a complex emission spectrum, spectral interferences are prone to affect the analysis of Al, calling for time consuming preparation steps to remove the U from the matrix. This study proposes a method of direct determination of Al in UAlx targets through the selection of specific emission lines enabled by the evaluation of the associated interferences on the recovery values.
Mercury exposure among dental staff in the Legal Amazon
2019 - VILLIBOR, FERNANDA F.; GUILHEN, SABINE N.; DANTAS, ELIZABETH S.K.; PIRES, MARIA A.F.
Elemental mercury is highly toxic and may be absorbed by dental professionals through direct skin contact or inhalation. The use of mercury in dental amalgam has been a concern of the academic community for years, for its incorporation is likely to affect vital organ systems. Several studies have been conducted to address the possible risks of occupational exposure to mercury vapor in dental offices. The present study aimed to present evidences that mercury is assimilated by exposed workers through the determination of urinary mercury (HgU) from dental professionals (n = 91) of public offices in Araguaína (Tocantins, Brazil). This uptake was verified against samples from unexposed individuals (n = 43), which activities are not dentistry related. Cold vapor atomic absorption spectrometry (CV-AAS) technique enabled the subjects’ biological monitoring. Approximately 44.8% (n = 60) of the 134 participants were aged between 21 and 30 years and were at the beginning of their professional lives; 9.7% (13) of the study participants were men and 90.3% (121) were women. Hg concentrations in all samples analyzed were within the maximum biological limit set by the World Health Organization (WHO) (<50 μgHg·L−1). HgU concentrations in dental professionals were within the limits proposed by the Brazilian regulatory standard, Regulatory Norm-7 (RN-7) (≤35 μgHg·g−1 creatinine). Nevertheless, the average concentration of HgU was approximately 8 times higher in the potentially exposed group (5.61 μgHg·g−1 creatinine) than in the unexposed group (0.65 μgHg·g−1 creatinine), highlighting the potential risk of occupational exposure to mercury.
Mercury exposure among dental staff in the legal Amazon
2019 - VILLIBOR, FERNANDA F.; GUILHEN, SABINE N.; DANTAS, ELIZABETH S.K.; PIRES, MARIA A.F.
Elemental mercury is highly toxic and may be absorbed by dental professionals through direct skin contact or inhalation. The use of mercury in dental amalgam has been a concern of the academic community for years, for its incorporation is likely to affect vital organ systems. Several studies have been conducted to address the possible risks of occupational exposure to mercury vapor in dental offices. The present study aimed to present evidences that mercury is assimilated by exposed workers through the determination of urinary mercury (HgU) from dental professionals (n = 91) of public offices in Araguaína (Tocantins, Brazil). This uptake was verified against samples from unexposed individuals (n = 43), which activities are not dentistry related. Cold vapor atomic absorption spectrometry (CV-AAS) technique enabled the subjects’ biological monitoring. Approximately 44.8% (n = 60) of the 134 participants were aged between 21 and 30 years and were at the beginning of their professional lives; 9.7% (13) of the study participants were men and 90.3% (121) were women. Hg concentrations in all samples analyzed were within the maximum biological limit set by the World Health Organization (WHO) (<50 μgHg·L−1). HgU concentrations in dental professionals were within the limits proposed by the Brazilian regulatory standard, Regulatory Norm-7 (RN-7) (≤35 μgHg·g−1 creatinine). Nevertheless, the average concentration of HgU was approximately 8 times higher in the potentially exposed group (5.61 μgHg·g−1 creatinine) than in the unexposed group (0.65 μgHg·g−1 creatinine), highlighting the potential risk of occupational exposure to mercury.
Application of bias correction methods to improve U3Si2 sample preparation for quantitative analysis by WDXRF
2019 - SCAPIN, M.A.; GUILHEN, S.N.; AZEVEDO, L.C.; COTRIN, M.E.B.; PIRES, M.A.F.
The determination of silicon (Si), total uranium (U) and impurities in uranium-silicide (U3Si2) samples by wavelength dispersion X-ray fluorescence technique (WDXRF) has been already validated and is currently implemented at IPEN’s X-Ray Fluorescence Laboratory (IPEN-CNEN/SP) in São Paulo, Brazil. Sample preparation requires the use of approx-imately 3 g of H3BO3 as sample holder and 1.8 g of U3Si2. However, because boron is a neutron absorber, this proce-dure precludes the recovery of U3Si2 from the samples, preventing its use as nuclear fuel. Consequently, a significant amount of uranium is wasted in this process. An estimated average of 15 samples per month is expected to be analyzed by WDXRF, resulting in approx. 320 g of U3Si2 that wouldn’t return to the nuclear fuel cycle. The purpose of this paper is to present a new preparation method, replacing H3BO3 by cellulose acetate {[C6H7O2(OH)3-m(OOCCH3)m], m = 0~3}, thus enabling the recovery of the boron-free U3Si2 from the samples. The results demonstrate that the suggested sample preparation approach is statistically satisfactory, allowing the optimization of the procedure.
Method development and validation for simultaneous determination of IEAR1 reactor's pool water U and Si content by ICP OES
2017 - ULRICH, JOAO C.; GUILHEN, SABINE N.; COTRIM, MARYCEL E.B.; PIRES, MARIA A.F.
Metodologia de liofilização de urina para determinação de mercúrio inorgânico
2015 - VILLIBOR, FERNANDA F.; GUILHEN, SABINE N.; DANTAS, ELIZABETH S.K.; PIRES, MARIA A.F.
Metodologia de liofilização de urina para determinação de mercúrio inorgânico
VILLIBOR, FERNANDA F.; GUILHEN, SABINE N.; DANTAS, ELIZABETH S.K.; PIRES, MARIA A.F.