DALTON GIOVANNI NOGUEIRA DA SILVA
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Artigo IPEN-doc 27794 Non-destructive analysis in the study of historical photographs by pXRF and ATR-FTIR spectroscopies2021 - ZAMBONI, CIBELE B.; REDÍGOLO, MARCELO M.; MIURA, VINICIUS T.; COSTA, ISOLDA; NAGAI, MARIA L.E.; SALVADOR, PABLO A.V.; SILVA, DALTON G.N. daMaterial characterization is essential to the provenance of graphic arts. Non-destructive analytical techniques are increasingly required in the authentication process of cultural heritage. This work presents a suite of portable, non-destructive, and complementary analytical techniques, energy dispersive x-ray fluorescence (EDXRF), Fourier transform infrared (FTIR) spectroscopies, and brightfield microscopy, applied to the analysis of historical photographs depicting São Paulo city architecture, whose registration date and process of fabrication are unknown. The EDXRF analysis emphasizes the use of typical POP (printing-out paper) photograph with baryta (BaSO4) coated paper substrate while the FTIR and microscopy analyses confirm the presence of collodion and a gelatin-based baryta layer. This photographic process was widely employed by professional photographers from 1889 to 1930, when it was gradually abandoned in commercial use. This time interval (1889–1930) is consistent with the information surveyed on the photographic collection. In conclusion, employing complementary techniques (elemental and molecular spectroscopies and image magnification) is essential in identifying the manufacturing materials of cultural heritage material, which is the basis of contemporary authentication procedures. These data provide to curators and historians fundamental information for cataloging, adding subsidies for the correct storage and preservation (“heritage appreciation”). Still, for professional photographers, they present information on the manufacturing processes of historical photographs. The data from the present study also emphasize its perspective of use in graphic arts to aid connoisseurship in identifying forgeries during provenance and authentication studies.Artigo IPEN-doc 26475 Multielemental analyses of Lonomia obliqua (Lepidoptera, Saturniidae) caterpillar using EDXRF and INAA techniques2019 - ZAMBONI, C.B.; GIOVANNI, D.N.S.; SALVADOR, V.L.R.; SATO, I.M.; MENDONÇA, R.Z.; WEN, F.H.; SIMONS, M.S.In this study, multielemental analysis of Lonomia obliqua (Lepidoptera, Saturniidae) caterpillar was performed using energy dispersive X‐ray fluorescence and instrumental neutron activation analysis techniques. This caterpillar is poisonous and has the ability to cause fatal hemorrhagic effects in humans after contact. The need of this study is related to morphological changes (mainly size and color) observed in some caterpillars used for preparation of antilonomic serum (antivenom). The samples were classified as healthy (caterpillars of control) and unhealthy (caterpillars visibly modified). The XRF measurements were performed in an energy dispersive X‐ray fluorescence spectrometer and the instrumental neutron activation analysis using the IEAR1 nuclear reactor at IPEN. The results show significant differences for several elements (mainly, P, Cl, Ca, Ti, Mn, Fe, Ni, and Zn) in unhealthy caterpillars that can affect the development of this species as well as the quality and yield of the antivenom. Furthermore, its elemental characterization contributes for the understanding the potential pharmacological (procoagulant and antithrombotic) in the prevention of life‐threatening blood clots.