MARINA BEATRIZ AGOSTINI VASCONCELLOS

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  • Artigo IPEN-doc 25077
    Stability assessment of a bovine kidney reference-material candidate
    2018 - CASTRO, LILIANA; MOREIRA, EDSON G.; VASCONCELLOS, MARINA B.A.; LANGE, CAMILA N.; PEDRON, TATIANA; BATISTA, BRUNO L.
    Reference materials are used worldwide and necessary for quality control purposes during analytical determinations. The present study describes the stability evaluation of a bovine kidney reference-material candidate. An isochronous layout was performed, in which the flasks involved are exposed at different temperatures for different time periods and then are analyzed at the same time at the end of the study. The mass fractions of ten inorganic constituents were determined using instrumental neutron activation analysis and inductively coupled plasma mass spectrometry. Statistical analysis, univariate and multivariate, showed no significant differences in composition between units exposed to the different temperatures and times. The reference material may be transported under normal transportation conditions and the certified values and uncertainties will continue to be valid for a period of 2 years.
  • Artigo IPEN-doc 24355
    Interlaboratory comparison for the characterization of a brazilian mussel reference material
    2018 - MOREIRA, EDSON G.; VASCONCELLOS, MARINA B.A.; MAIHARA, VERA A.; CATHARINO, MARILIA G.M.; SAIKI, MITIKO
    Bivalve mollusks have long been used in biomonitoring studies to assess seawater environmental status. The use of suitable certified reference materials is a straightforward means to attain quality assurance in such studies as they allow the traceability of measurement results, making it possible the comparison of data obtained at different places and periods of time. This paper describes the certification of element mass fractions for a Perna perna mussel reference material produced in Brazil. After homogeneity and stability studies, an interlaboratory comparison was performed for element characterization. Robust means were taken as assigned values and contributions due to element characterization and from homogeneity and stability studies were taken into account to yield expanded uncertainties. From the adopted certification criteria, informative values for 20 elements were obtained and it was possible to assign certified values for the following 16 elements: Al, As, Ca, Cd, Cl, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Se, Th and Zn.
  • Artigo IPEN-doc 24336
    Use of INAA in the homogeneity evaluation of a bovine kidney candidate reference material
    2017 - CASTRO, LILIANA; MOREIRA, EDSON G.; VASCONCELLOS, MARINA B.A.
    Instrumental neutron activation analysis was used to evaluate the between bottle homogeneity and the minimum sample intake of a bovine kidney candidate reference material. The mass fractions of ten inorganic constituents were determined, obtaining satisfactory homogeneity results for all of them. Statistical analysis of the results was performed using a one way analysis of variance and multivariate techniques were applied as complementary techniques, confirming the usefulness of these techniques for homogeneity assessment.
  • Artigo IPEN-doc 22766
    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.
  • Artigo IPEN-doc 22400
    Contribution to food safety assurance of fish consumed at São Paulo city by means of trace element determination
    2016 - FABIANO, KAREN C.; LIMA, ANA P.S.; VASCONCELLOS, MARINA B.A.; MOREIRA, EDSON G.
  • Artigo IPEN-doc 20722
    Passive biomonitoring study and effect biomarker in oysters Crassostrea brasiliana (Lamark, 1819: Mollusca, Bivalvia) in Santos and Cananéia Estuaries in São Paulo State, Brazil
    2015 - CATHARINO, M.G.M.; VASCONCELLOS, M.B.A.; KIRSCHBAUM, A.A.; GASPARO, M.R.; SOUSA, E.C.P.M. de; MINEI, C.C.; MOREIRA, E.G.
    This study assessed the exposure and effects of trace elements in sentinel organisms, using the bivalve Crassostrea brasiliana in two estuarine areas in Sa˜o Paulo State, Brazil: Santos Estuary and Canane´ia Estuary, site of oyster farms, which was used as reference site. Oysters were evaluated for bioaccumulation of As, Co, Cr, Fe, Se and Zn by INAA and Cd, Pb and Hg by AAS. Effect biomarker was assessed by evaluation of lysosomal membrane stability. In the study of bioaccumulation of trace elements it was verified that Santos Channel presented the largest concentrations of elements studied in most cases. From the study of the cellular biomarker, it was verified that Santos Channel and winter showed higher stress to organisms in the present study.
  • Artigo IPEN-doc 20261
    Element content and particle size characterization of a mussel candidate reference material
    2015 - MOREIRA, E.G.; VASCONCELLOS, M.B.A.; SANTOS, R.G.; MARTINELLI, J.R.