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Papers by solange souza
Electrochemical and Solid State Letters, 2001
Coating strategies for corrosion protection considering intrinsically electronic conducting polym... more Coating strategies for corrosion protection considering intrinsically electronic conducting polymers have become important mainly because of restrictions on the use of heavy metals due to their environmental problems. This work presents the electrochemical behavior of an acrylic blend formed by sulfonate-doped polyaniline and poly͑methyl methacrylate͒ used for corrosion protection of iron in chloride solutions. The results would indicate that these blends have a dual protection mechanism; forming a passivating complex with the dopant anion ͑camphorsulfonate͒ and simultaneously acting as a physical barrier to avoid chloride anion penetration.
Electrochimica Acta, 2005
Coating strategies for corrosion protection based on intrinsically electronic conducting polymers... more Coating strategies for corrosion protection based on intrinsically electronic conducting polymers, become an important research field mainly due to restrictions to the use of heavy metals, which are related to environmental problems. This work presents the corrosion protection behavior of different metals by using coatings based on acrylic blends formed by polyaniline and poly(methyl methacrylate). Raman spectroscopy revealed that the oxidation state of the PANI component of the blend at undamaged films, depends on the metal surface used as substrate. Results indicate that the degree of redox conversion of polyaniline, from emeraldine to leucoemeraldine state, strongly depends on the reducing power of metals showing a galvanic coupling between the substrate and polyaniline. On the other way, results reveal that PANI acts as an anion reservoir, which can release anions in a smart way when damage is produced on the surface of the coating forming a second physical barrier to avoid penetration of aggressive ions. This phenomenon was observed for all metal studied in this work.
Quimica Nova, 2008
Few articles deal with lead and strontium isotopic analysis of water samples. The aim of this stu... more Few articles deal with lead and strontium isotopic analysis of water samples. The aim of this study was to define the chemical procedures for Pb and Sr isotopic analyses of groundwater samples from an urban sedimentary aquifer. Thirty lead and fourteen strontium isotopic analyses were performed to test different analytical procedures. Pb and Sr isotopic ratios as well as Sr concentration did not vary using different chemical procedures. However, the Pb concentrations were very dependent on the different procedures. Therefore, the choice of the best analytical procedure was based on the Pb results, which indicated a higher reproducibility from samples that had been filtered and acidified before the evaporation, had their residues totally dissolved, and were purified by ion chromatography using the Biorad® column. Our results showed no changes in Pb ratios with the storage time.
Electrochemical and Solid State Letters, 2001
Coating strategies for corrosion protection considering intrinsically electronic conducting polym... more Coating strategies for corrosion protection considering intrinsically electronic conducting polymers have become important mainly because of restrictions on the use of heavy metals due to their environmental problems. This work presents the electrochemical behavior of an acrylic blend formed by sulfonate-doped polyaniline and poly͑methyl methacrylate͒ used for corrosion protection of iron in chloride solutions. The results would indicate that these blends have a dual protection mechanism; forming a passivating complex with the dopant anion ͑camphorsulfonate͒ and simultaneously acting as a physical barrier to avoid chloride anion penetration.
Electrochimica Acta, 2005
Coating strategies for corrosion protection based on intrinsically electronic conducting polymers... more Coating strategies for corrosion protection based on intrinsically electronic conducting polymers, become an important research field mainly due to restrictions to the use of heavy metals, which are related to environmental problems. This work presents the corrosion protection behavior of different metals by using coatings based on acrylic blends formed by polyaniline and poly(methyl methacrylate). Raman spectroscopy revealed that the oxidation state of the PANI component of the blend at undamaged films, depends on the metal surface used as substrate. Results indicate that the degree of redox conversion of polyaniline, from emeraldine to leucoemeraldine state, strongly depends on the reducing power of metals showing a galvanic coupling between the substrate and polyaniline. On the other way, results reveal that PANI acts as an anion reservoir, which can release anions in a smart way when damage is produced on the surface of the coating forming a second physical barrier to avoid penetration of aggressive ions. This phenomenon was observed for all metal studied in this work.
Quimica Nova, 2008
Few articles deal with lead and strontium isotopic analysis of water samples. The aim of this stu... more Few articles deal with lead and strontium isotopic analysis of water samples. The aim of this study was to define the chemical procedures for Pb and Sr isotopic analyses of groundwater samples from an urban sedimentary aquifer. Thirty lead and fourteen strontium isotopic analyses were performed to test different analytical procedures. Pb and Sr isotopic ratios as well as Sr concentration did not vary using different chemical procedures. However, the Pb concentrations were very dependent on the different procedures. Therefore, the choice of the best analytical procedure was based on the Pb results, which indicated a higher reproducibility from samples that had been filtered and acidified before the evaporation, had their residues totally dissolved, and were purified by ion chromatography using the Biorad® column. Our results showed no changes in Pb ratios with the storage time.