Solid Phase Preconcentration
Mostrando 13-24 de 67 artigos, teses e dissertações.
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13. Solid Phase Extraction to On-Line Preconcentrate Trace Cadmium Using Chemically Modified Nano-Carbon Black with 3-Mercaptopropyltrimethoxysilane
Carbon black (CB) grafted with 3-mercaptopropyltrimethoxysilane (3-MPTMS) was used as solid phase extractor for Cd2+ in a flow injection system coupled to flame atomic absorption spectrometry (FAAS). The influence of pH, buffer concentration, preconcentration flow rate and eluent concentration on preconcentration of Cd2+ were investigated by means of chemome
J. Braz. Chem. Soc.. Publicado em: 2016-10
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14. On-line Green Solid Phase Extraction of Trace Rare Earth Elements and Uranium in Environmental Samples and ICP OES Detection
An on-line solid phase extraction (SPE) method using mini column packed with natural sorbent based on cotton roll dyed by quinalizarin was developed for simultaneously pre-concentration of rare earth elements and uranium at trace levels in environmental samples followed by inductively coupled plasma optical emission spectrometry (ICP OES) determination. Vari
J. Braz. Chem. Soc.. Publicado em: 2016-10
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15. Validation of a liquid chromatography ultraviolet method for determination of herbicide diuron and its metabolites in soil samples
ABSTRACT Diuron is one of the most widely herbicide used worldwide, which can undergo degradation producing three primary metabolites: 3,4-dichlorophenylurea, 3-(3,4-dichlorophenyl)-1-methylurea, and 3,4-dichloroaniline. Since the persistence of diuron and its by-products in ecosystems involves risk of toxicity to environment and human health, a reliable qua
An. Acad. Bras. Ciênc.. Publicado em: 25/08/2016
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16. Synthesis and Characterization of Nanopore MoVI-Imprinted Polymer and Its Application as Solid Phase for Extraction, Separation and Preconcentration of Molybdenum Ions from Water Samples
The purpose of this study is to prepare a new ion imprinted polymer for MoVI with high selectivity. Ion-imprinted polymer (IIP) particles were synthesized by thermally copolymerization. For the synthesis of the ion imprinted polymer, the ion pair of (MoVI-thiocyanate) and NR4+ was used. The ion pair was precipitated in an aqueous phase and then dissolved in
J. Braz. Chem. Soc.. Publicado em: 2016-06
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17. Agarose Based Magnetic Solid-Phase Extraction-Magnetic Field Agitation for Determination of Trace Amounts of Molybdenum in Beans
A magnetic solid-phase extraction method based on agarose coated magnetic nanoparticles (ACMNPs) coupled to a magnetic field agitation (MFA) device was developed and used for the preconcentration and graphite furnace atomic absorption spectrometric determination of trace amounts of MoVI in beans. The formation of the nanoparticles and their encapsulation in
J. Braz. Chem. Soc.. Publicado em: 2016-04
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18. Magnetic Nanoparticles Coated with Ionic Liquid as a Sorbent for Solid Phase Extraction of Chromium(VI) Prior to Its Determination by Electrothermal Atomic Absorption Spectrometry
A simple, sensitive and reliable method for the separation, preconcentration and determination of ultra trace amounts of chromium species has been developed. Chromium(VI) in aqueous sample was reacted with 9-phenyl-2,3,7-trihydroxy-6-fluorone to produce a chelate at pH of 5.0 and extracted onto the magnetic nanoparticles coated with the ionic liquid 1-hexade
J. Braz. Chem. Soc.. Publicado em: 2016-01
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19. Separation and Preconcentration of Trace Amounts of Lead from Water Samples Using Solvent-Assisted Dispersive Solid Phase Extraction
This paper describes a new approach for the preconcentration of lead (Pb2+) by solventassisted dispersive solid phase extraction (SADSPE) prior to analyzing by flame atomic absorption spectrometry (FAAS). In this method, the dispersion of the sorbent was achieved by injecting a solution of the sorbent into the aqueous sample. Thereby, a cloudy
J. Braz. Chem. Soc.. Publicado em: 2015-08
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20. An Ion-Pair Reagent Incorporated Polystyrene Nanofiber Applied to Solid Phase Extraction of 5-Hydroxytryptamine in Human Plasma
Polystyrene (PS) nanofibers incorporated with ion-pair (IP) reagent, e.g., sodium dodecyl sulfonate (SDSn), were developed as functional adsorbents for the solid-phase extraction (SPE) of ionic neurotransmitter such as 5-hydroxytryptamine (5-HT), prior to the determination by high performance liquid chromatography-fluorescence detection (HPLC-FLD). A compreh
J. Braz. Chem. Soc.. Publicado em: 2015-03
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21. Ligand-Less in situ Surfactant-Based Solid Phase Extraction for Preconcentration of Cobalt, Nickel and Zinc from Water Samples Prior to their FAAS Determination
Uma nova e simples extração de fase sólida (LL-ISSPE), baseada em surfactante, sem ligantes e in situ foi desenvolvida para a pré-concentração de cobalto, níquel e zinco em amostras de água. Neste método, um surfactante catiônico contendo um grupo alquila (brometo de n-dodeciltrimetilamônio) é
J. Braz. Chem. Soc.. Publicado em: 2015-01
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22. Preconcentration and determination of organochlorine pesticides in seawater samples using polyaniline/polypyrrole-cellulose nanocomposite-based solid phase extraction and gas chromatography-electron capture detection
Neste trabalho, o papel de filtro quimicamente modificado com polianilina/polipirrol (PANI/PPY), denominado de nanocompósito PANI/PPY/celulose, foi preparado e usado como sorvente para extração em fase sólida (SPE) para a pré-concentração e extração de alguns pesticidas organoclorados (OCPs) em amostras de águas naturais. O sorvente proposto també
J. Braz. Chem. Soc.. Publicado em: 2014-11
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23. Preconcentration and determination of cadmium in water and food samples by in situ surfactant-based solid-phase extraction and flame atomic absorption spectrometry
A extração em fase sólida baseada em tensoativos in situ (ISS-SPE) é proposta como um procedimento de pré-concentração na determinação de cádmio em amostras de água e comida por espectrometria de absorção atômica de chama. No presente trabalho, utilizou-se brometo de cetiltrimetilamônio como um tensoativo catiônico, íon hexafluorfosfato como
J. Braz. Chem. Soc.. Publicado em: 2014-06
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24. Pre-concentration of traces of cadmium, cobalt, nickel and lead in natural honeys by solid phase extraction followed by their determination using flame atomic absorption spectrometry
Neste trabalho foi proposto um procedimento de preparo de amostra simples e rápido, para a determinação de traços de Cd, Co, Ni e Pb em méis. O procedimento consiste no preparo da amostra em meio ácido para a retenção dos elementos de interesse em uma resina de troca catiônica fortemente ácida, Dowex 50W×8-400, e a eluição com uma solução de H
J. Braz. Chem. Soc.. Publicado em: 2014-02