Zobrazeno 1 - 10
of 35
pro vyhledávání: '"Sônia Regina Giancoli Barreto"'
Autor:
Wagner José Barreto, Herica Aparecida Magosso, Miriam Fátima Soares, Bruno Marco Oliveira Silveira, Ieda Spacino Scarminio, Dílson Norio Ishikawa, Sônia Regina Giancoli Barreto
Publikováno v:
Eclética Química, Vol 36, Iss 3, Pp 15-20 (2018)
A simple and sensitive UV-Vis spectrophotometric method was developed using a new chromogenic reagent, L-dopasemiquinone, for the quantification of Ni(II) in metallic alloys: Inox, Co-Cr, and Ni-Ti. The complex [Ni(II)(L1-)3]1- presents an intense ba
Externí odkaz:
https://doaj.org/article/4cf8d4288eae43d5a0697c00496483bb
Autor:
Bruna Fabrin Somera, Fernanda Midori de Oliveira, Wagner José Barreto, Sônia Regina Giancoli Barreto, César Ricardo Teixeira Tarley
Publikováno v:
Química Nova, Vol 35, Iss 8, Pp 1600-1605 (2012)
The present study proposes a method for cloud point preconcentration of copper ions at pH 2.0 based on complexes formed with [4,5-dimercapto-1,3-dithyol-2-thionate] and subsequent determination by flame atomic absorption spectrometry (FAAS). Under op
Externí odkaz:
https://doaj.org/article/525dec0331e643d59cf21f079c754d0c
Autor:
Dílson Norio Ishikawa, Renata Zacarias Noale, Thiago Hideyuki Kobe Ohe, Eloana Benassi Ribeiro de Souza, Ieda Spacino Scarmínio, Wagner José Barreto, Sônia Regina Giancoli Barreto
Publikováno v:
Química Nova, Vol 32, Iss 7, Pp 1744-1749 (2009)
The proposal of this study was to obtain the profile of these metals distribution Al, Co, Cu, Pb, Cr, Ni, Co and Zn in sediments from lakes in the city of Londrina-PR and evaluate the environmental risk resulting from such distribution. The parameter
Externí odkaz:
https://doaj.org/article/4bce4f2709f24292bcf77df4067529c9
Publikováno v:
Química Nova, Vol 29, Iss 6, Pp 1255-1258 (2006)
The reaction of 1,2-dihydroxy-benzene (pyrocatechol) (C6H6O2) with iron oxide (Fe2O3) and sodium thiosulfate (Na2S2O3) in aqueous medium (pH 7) was investigated. Pyrocatechol suffers autoxidation and coordinates with Fe3+ in solution. The presence of
Externí odkaz:
https://doaj.org/article/c798d14c11ec4ada8d74fa3a70496866
Publikováno v:
Semina: Ciências Exatas e Tecnológicas. 32:181-190
In this study, we used the reports of classroom observation as a research tool, serving as a tool for research on initial teacher training in chemistry. The study analyzed 12 reports prepared by students of Degree in Chemistry and to discuss through
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d8b29b5547fbf02a6f4a92e25058234f
https://doi.org/10.5433/1679-0375.2011v32n2p181
https://doi.org/10.5433/1679-0375.2011v32n2p181
Publikováno v:
CLEAN - Soil, Air, Water. 39:362-367
The values for the partition coefficient (K d ) were calculated for Ca, Mg, Cd, Cr, Cu, Fe, Mn, Pb, Ni, and Zn at 19 sites in the Capivara hydroelectric reservoir in Brazil. It was found that the relative values of K d follow the order: Cr > Mn > Fe
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d2619ab97e2cbef1fed74aab3c207d7b
https://doi.org/10.1002/clen.201000271
https://doi.org/10.1002/clen.201000271
Publikováno v:
Analytical Letters. 43:814-822
UV-Vis spectrophotometry and multivariate calibration model, Principal Components Regression (PCR), were used for individual and simultaneous quantification of ternary mixtures of reactive dyes (Yellow Procion HE4R, Navy Blue Procion HER, and Blue Pr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::fd22231ffdad27a3f3cb171f14695a01
https://doi.org/10.1080/00032710903486278
https://doi.org/10.1080/00032710903486278
Autor:
Marcus Vinícius Brás de Proença, Dílson Norio Ishikawa, Ieda Spacino Scarminio, Miriam de Fatima Soares, Sônia Regina Giancoli Barreto, Wagner José Barreto
Publikováno v:
Química Nova, Vol 33, Iss 1, Pp 109-113 (2010)
Química Nova, Volume: 33, Issue: 1, Pages: 109-113, Published: 2010
Química Nova v.33 n.1 2010
Química Nova
Sociedade Brasileira de Química (SBQ)
instacron:SBQ
Química Nova, Volume: 33, Issue: 1, Pages: 109-113, Published: 2010
Química Nova v.33 n.1 2010
Química Nova
Sociedade Brasileira de Química (SBQ)
instacron:SBQ
A spectrophotometric method was proposed for Ni(II) determination in alloys using a dopa-semiquinone (L-1) to form [Ni(II)(L1-)3]1-, ε = 9.3 x 10³ L mol-1 cm-1. The optimal conditions for the determination were: wavelength 590 nm, temperature 25 °
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3b63404d81be2d5279af33a9f7009077
https://doi.org/10.1590/s0100-40422010000100020
https://doi.org/10.1590/s0100-40422010000100020
Publikováno v:
Transition Metal Chemistry. 34:677-681
The reaction between Fe(III) and dopamine in aqueous solution in the presence of Na2S2O3 was followed through UV–Vis spectroscopy, pH and oxy-reduction potential (Eh) measurements. The formation and quick disappearing of the complex [Fe(III)HL1−]
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b171f909fe9433e258a74259c0112a25
https://doi.org/10.1007/s11243-009-9247-3
https://doi.org/10.1007/s11243-009-9247-3
Autor:
Thiago Hideyuki Kobe Ohe, Sônia Regina Giancoli Barreto, Dílson Norio Ishikawa, Ieda Spacino Scarminio, Wagner José Barreto, Eloana Benassi Ribeiro de Souza, Renata Zacarias Noale
Publikováno v:
Química Nova, Volume: 32, Issue: 7, Pages: 1744-1749, Published: 2009
Química Nova v.32 n.7 2009
Química Nova
Sociedade Brasileira de Química (SBQ)
instacron:SBQ
Química Nova v.32 n.7 2009
Química Nova
Sociedade Brasileira de Química (SBQ)
instacron:SBQ
The proposal of this study was to obtain the profile of these metals distribution Al, Co, Cu, Pb, Cr, Ni, Co and Zn in sediments from lakes in the city of Londrina-PR and evaluate the environmental risk resulting from such distribution. The parameter
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b7930ebc42ebbe72c376d4efa8fba044
https://doi.org/10.1590/s0100-40422009000700012
https://doi.org/10.1590/s0100-40422009000700012