Search Results - "Ferreira, Sérgio Luís Costa"

Recent developments in the application of cloud point extraction as procedure for speciation of trace elements by Bezerra, Marcos Almeida, Ferreira da Mata Cerqueira, Uillian Mozart, Ferreira, Sérgio Luís Costa, Novaes, Cleber Galvão, Novais, Franciele Castro, Valasques, Gisseli Souza, Novaes da Silva, Bruno

“…This review addresses the use of cloud point extraction as a separation and pre-concentration method aiming at the speciation of metals and metalloids by…”
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Chemometric tools in electroanalytical chemistry: Methods for optimization based on factorial design and response surface methodology by Tarley, César Ricardo Teixeira, Silveira, Gustavo, dos Santos, Walter Nei Lopes, Matos, Geraldo Domingues, da Silva, Erik Galvão Paranhos, Bezerra, Marcos Almeida, Miró, Manuel, Ferreira, Sérgio Luis Costa

“…The aim of this paper is to give a brief overview of chemometric techniques based on factorial designs and response surface methodologies used in the…”
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A Method Based on Digital Image Colorimetry for Determination of Total Phenolic Content in Fruits by Costa, Rafael Conceição, Leite, Jéssica Costa, Brandão, Geovani Cardoso, Ferreira, Sérgio Luis Costa, dos Santos, Walter Nei Lopes

“…In this study, a method based on digital image colorimetry was developed for the determination of the total phenolic content in fruits, using the Folin-Denis…”
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Organic Sulfur Markers as Proxies of Depositional Paleoeenvironments Related to Recôncavo and Amazon Basins, Brazil by Nery do Amaral, Diego, Miranda, Flávia Lima e Cima, de Oliveira, Lua Morena Leôncio, Cerqueira, José Roberto, Ribeiro, Hélio Jorge Portugal Severiano, Oliveira, Olívia Maria Cordeiro, Queiroz, Antônio Fernando de Souza, Ferreira, Sérgio Luís Costa, Machado, Maria Elisabete

“…This study employed organic sulfur markers (S-markers) associated with geochemistry parameters to evaluate the paleoenvironment of different depositional…”
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Cloud Point Extraction as a Procedure of Separation and Pre-Concentration for Metal Determination Using Spectroanalytical Techniques: A Review by Bezerra, Marcos de Almeida, Arruda, Marco Aurélio Zezzi, Ferreira, Sérgio Luis Costa

“…Cloud point extraction is a separation and preconcentration procedure that has been extensively applied for trace metal determination in several different…”
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Optimization of microwave assisted digestion procedure for the determination of zinc, copper and nickel in tea samples employing flame atomic absorption spectrometry by Soylak, Mustafa, Tuzen, Mustafa, Souza, Anderson Santos, Korn, Maria das Graças Andrade, Ferreira, Sérgio Luis Costa

“…The present paper describes the development of a microwave assisted digestion procedure for the determination of zinc, copper and nickel in tea samples…”
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Multivariate optimization of a solid phase microextraction-headspace procedure for the determination of benzene, toluene, ethylbenzene and xylenes in effluent samples from a waste treatment plant by Gaujac, Alain, Emídio, Elissandro Soares, Navickiene, Sandro, Ferreira, Sérgio Luis Costa, Dórea, Haroldo Silveira

“…A method based on solid-phase microextraction (SPME) and gas chromatography with flame ionization detection (GC-FID) has been optimized for the determination…”
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A Pre-Concentration Procedure Using Cloud Point Extraction for the Determination of Uranium in Natural Water by Ferreira, Hadla Sousa, Bezerra, Marcos de Almeida, Costa Ferreira, Sérgio Luis

“…A pre-concentration procedure using cloud point extraction is presented for the determination of uranium in natural water using molecular absorption…”
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Extraction induced by emulsion breaking for As, Se and Hg determination in crude palm oil by vapor generation-AFS by Souza Valasques, Gisseli, Maria Pinto dos Santos, Ana, Levi França da Silva, Daniel, Mozart Ferreira da Mata Cerqueira, Uillian, Luis Costa Ferreira, Sérgio, Nei Lopes dos Santos, Walter, Almeida Bezerra, Marcos

“…•As, Se and Hg were determined using AFS after extraction induced by emulsion breaking.•Multivariate optimization was employed to optimize the extraction…”
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Assessment of toxicity of metals in river sediments for human supply: Distribution, evaluation of pollution and sources identification by Almeida, Lucas Cintra, da Silva Júnior, Jucelino Balbino, dos Santos, Ivanice Ferreira, de Carvalho, Vanessa Sales, de Santana Santos, Adilson, Hadlich, Gisele Mara, Ferreira, Sérgio Luís Costa

“…Ten surface sediments collected from Joanes River, Bahia, Brazil in rainy and drought periods in 2019 were evaluated according to the enrichment factor (EF),…”
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A New Simple and Fast Method for Determination of Cobalt in Vitamin B12 and Water Samples Using Dispersive Liquid-Liquid Microextraction and Digital Image Analysis by Lemos, Valfredo Azevedo, Junior, Ivanilson Vieira Souza, Santos, Luana Bastos, Barreto, Jeferson Alves, Ferreira, Sérgio Luís Costa

“…In this work, a simple and fast method for the determination of cobalt in vitamin B12 and water samples was developed. The procedure is based on the…”
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Solid-Phase Extraction and Detection by Digital Image Directly in the Sorbent: Determination of Nickel in Environmental Samples by Santos, Luana Bastos, Barreto, Jeferson Alves, dos Santos de Assis, Rosivan, de Souza, Cheilane Tavares, Ferreira, Sérgio Luís Costa, Novaes, Cleber Galvão, Lemos, Valfredo Azevedo

“…Recently, analytical procedures based on computer vision related to the colorimetric analysis of digital images have been described in the scientific…”
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Atomic spectrometric methods for the determination of metals and metalloids in automotive fuels – A review by Korn, Maria das Graças Andrade, Santos, Denilson Santana Sodré dos, Welz, Bernhard, Vale, Maria Goreti Rodrigues, Teixeira, Alete Paixão, Lima, Daniel de Castro, Ferreira, Sérgio Luis Costa

“…Gasoline, diesel, ethanol and more recently also biodiesel are the four types of fuel used for automobile, truck and other transportation vehicle. The presence…”
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Synthesis of a New Solid-Phase Extractor and Its Application to Preconcentration and Determination of Lead in Water Samples by GALVAO NOVAES, Cleber, SILVA SANTOS, Juracir, FERREIRA, Sérgio Luis Costa, AZEVEDO LEMOS, Valfredo

“…A procedure for preconcentration and determination of lead in water is described. The method is based on the sorption of Pb(II) in a minicolumn packed with a…”
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Factorial design in the optimization of preconcentration procedure for lead determination by FAAS by Soylak, Mustafa, Narin, Ibrahim, Bezerra, Marcos de Almeida, Ferreira, Sérgio Luís Costa

“…The present paper proposes a preconcentration procedure for lead determination using flame atomic absorption spectrometry (FAAS). It is based on lead(II) ions…”
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Spectrophotometric determination of uranium using 2-(2- Thiazolylazo)-p-Cresol (TAC) in the presence of surfactants by Teixeira, Leonardo Sena Gomes, Costa, Antonio Celso Spínola, Ferreira, Sérgio Luís Costa, Freitas, Maria de Lourdes, Carvalho, Marcelo Souza de

“…A sensitive and selective spectrophotometric method is proposed for the rapid determination of uranium using 2-(2- Thiazolylazo)-p-Cresol (TAC). The reaction…”
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Multivariate technique for optimization of digestion procedure by focussed microwave system for determination of Mn, Zn and Fe in food samples using FAAS by Santelli, Ricardo Erthal, Bezerra, Marcos de Almeida, de SantAna, Otoniel Domingos, Cassella, Ricardo Jorgensen, Ferreira, Sérgio Luis Costa

“…This article describes the development by response surface methodology (RSM) of a procedure for iron, zinc and manganese determination by flame atomic…”
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Application of pyridylazo and thiazolylazo reagents in flow injection preconcentration systems for determination of metals by Baliza, Patrícia Xavier, Ferreira, Sérgio Luis Costa, Teixeira, Leonardo Sena Gomes

“…Pyridylazo and thiazolylazo reagents are synthetic dyes widely used in analytical chemistry. These reagents are also very attractive for use in…”
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Simultaneous optimization of multiple responses and its application in Analytical Chemistry – A review by Bezerra, Marcos Almeida, Ferreira, Sérgio Luis Costa, Novaes, Cleber Galvão, dos Santos, Ana Maria Pinto, Valasques, Gisseli Souza, da Mata Cerqueira, Uillian Mozart Ferreira, dos Santos Alves, Juscelia Pereira

“…This manuscript covers the application of the main techniques for simultaneous optimization of multiple responses generated by the application of multivariate…”
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Doehlert design in the optimization of procedures aiming food analysis – A review by Cerqueira, Uillian Mozart Ferreira Mata, Bezerra, Marcos Almeida, Ferreira, Sérgio Luís Costa, de Jesus Araújo, Rodrigo, da Silva, Bruno Novaes, Novaes, Cleber Galvão

“…•Doehlert design in the optimization of food analytical methods.•Didactic approach about its main characteristics.•Critical discussion of its advantages,…”
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