Doehlert Design
Mostrando 1-12 de 19 artigos, teses e dissertações.
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1. Development of Analytical Method for Determination of Inorganic Constituents in Powder Refreshment Using Dilute Mineral Acids and Detection by ICP OES
An analytical method for multi-elementary determination in powder refreshment, based on sample digestion using dilute mineral acids and detection by inductively plasma coupled optical emission spectrometry (ICP OES) is proposed. Chemometric tools, such as fractional factorial design and principal component analysis (PCA) and hierarchical cluster analysis (HC
J. Braz. Chem. Soc.. Publicado em: 2021-07
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2. Development of a Methodology Based on Extraction Induced by Emulsion Breaking for Copper Determination in Gasohol by Graphite Furnace Atomic Absorption Spectrometry
The development of a method based on extraction induced by emulsion breaking (EIEB) aiming copper determination in gasohol using graphite furnace atomic absorption spectrometry (GF AAS) is reported. Emulsification of the gasohol samples was carried out using nitric acid solution, (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol surfactant (Triton X-114),
J. Braz. Chem. Soc.. Publicado em: 2021-02
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3. Multivariate Analysis: Use of Doehlert Design (DD) for Optimization of a Simple Sample Preparation Procedure for the Determination of Inorganic Constituents in Cocoa Beans Employing Microwave Acid Digestion and ICP OES
This study presents a microwave-assisted procedure for sample preparation of cocoa beans using diluted HNO3 with H2O2 for the determination of Ba, Ca, Cu, K, Mg, Mn, P, S, Sr and Zn by inductively coupled plasma optical emission spectrometry (ICP OES). Doehlert modified design was used for optimization of experimental condition, and the volume of H2O2 (0, 0.
J. Braz. Chem. Soc.. Publicado em: 2020-10
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4. The paths of Graves’ disease in the 21st century: precision medicine is closer
This study presents a microwave-assisted procedure for sample preparation of cocoa beans using diluted HNO3 with H2O2 for the determination of Ba, Ca, Cu, K, Mg, Mn, P, S, Sr and Zn by inductively coupled plasma optical emission spectrometry (ICP OES). Doehlert modified design was used for optimization of experimental condition, and the volume of H2O2 (0, 0.
Arch. Endocrinol. Metab.. Publicado em: 2020-10
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5. Performance of Avocado Seed Activated Carbon as Adsorbent for Highly Sensitive Determination of Cd Using a Flow Injection System Online Coupled to TS-FF-AAS
A flow-injection preconcentration system using detection by the thermospray flame furnace atomic absorption spectrometry (FIA-TS-FF-AAS) is proposed. Cd2+ are adsorbed on avocado seed activated carbon (ASAC) packed into a cylindrical mini-column and eluted using HCl solutions for the detection system. A 25–1 fractional factorial and Doehlert matrix design
J. Braz. Chem. Soc.. Publicado em: 2020-01
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6. Analytical Strategies for Determination and Environmental Impact Assessment of Inorganic Antimony Species in Natural Waters Using Hydride Generation Atomic Fluorescence Spectrometry (HG AFS)
This study proposes an optimized procedure for the determination of inorganic antimony species in natural waters using hydride generation atomic fluorescence spectrometry (HG AFS) and continuous flow system. The variables of the hydride generation system, such as pre-reduction time, hydrochloric acid concentration and sodium tetrahydroborate concentration, w
J. Braz. Chem. Soc.. Publicado em: 2018-01
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7. Evaluation of volatile profiles obtained for minimally-processed pineapple fruit samples during storage by headspace-solid phase microextraction gas chromatography-mass spectrometry
Abstract This paper describes the application of the solid-phase microextraction (SPME) technique for the determination and monitoring of the volatile profile of minimally-processed pineapple fruit stored at various temperatures (-12 °C, 4 °C and 25 °C) for different periods (1, 4 and 10 days). The SPME fiber coating composed of Car/PDMS presented the bes
Food Sci. Technol. Publicado em: 09/03/2017
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8. Multivariate optimization of a method for antimony determination by hydride generation atomic fluorescence spectrometry in hair samples of patients undergoing chemotherapy against Leishmaniasis
ABSTRACT A method was developed for determination of total antimony in hair samples from patients undergoing chemotherapy against Leishmaniasis based on the administration of pentavalent antimonial drugs. The method is based on microwave assisted digestion of the samples in a pressurized system, reduction of Sb5+ to Sb3+ with KI solution (10% w/v) in ascorbi
An. Acad. Bras. Ciênc.. Publicado em: 25/08/2016
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9. OTIMIZAÇÃO DO PROCESSO DE TRANSESTERIFICAÇÃO EM DUAS ETAPAS PARA PRODUÇÃO DE BIODIESEL ATRAVÉS DO PLANEJAMENTO EXPERIMENTAL DOEHLERT
In this work, Doehlert experimental design was used to optimize the Transesterification Double Step Process (TDSP) method of methyl soybean oil biodiesel production which starts with a basic catalysis followed by an acidic catalysis. The conversion values were calculated from NMR spectra. Response surface was used to show the results of the interactions betw
Quím. Nova. Publicado em: 2016-04
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10. Multivariate Optimization of a Simultaneous Cloud Point Extraction Procedure of Cd, Cu and Ni from Sediments Samples and Determination by ICP OES
A simultaneous preconcentration method for cadmium, copper and nickel in samples of sediments and determination by inductively coupled plasma optical emission spectrometry was developed. The method is based on the extraction of the metals as complexes formed with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (5-Br-PADAP) at cloud point of the nonionic sur
J. Braz. Chem. Soc.. Publicado em: 2016-04
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11. Determinação de anti-inflamatórios em efluente urbano na região de Porto Alegre-RS por SPE, derivatização e GC-MS
In this work the development of an analytic methodology was studied to determine and quantify seven non-steroidal anti-inflammatory drugs, widely used in human treatment, and caffeine considered an anthropogenic marker. The compounds studied were acetaminophen (AC), salicylic acid (AS), caffeine (CA), ketoprofen (CE), diclofenac (DC), dipyrone (DP), ibuprofe
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2012
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12. Extração induzida por quebra de emulsão: uma nova estratégia para determinação de metais traços em amostras de óleo / Extração induzida por quebra de emulsão: uma nova estratégia para determinação de metais traços em amostras de óleo / Extraction induced by emulsion breaking: a new strategy for the trace metals determination oil sample / Extraction induced by emulsion breaking: a new strategy for the trace metals determination oil sample
The present work reports the development of a novel methodology for the determination of trace metals in organic liquids. The method is based on the extraction induced by emulsion breaking, which is carried out with the formation of a stable emulsion between the oil (10 mL) and an aqueous phase (2 mL) containing a surfactant and acid. After that, the emulsio
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 19/07/2011