Alternative Solvent
Mostrando 1-12 de 118 artigos, teses e dissertações.
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1. Development of a Disposable Pipette Extraction Method Using Coffee Silverskin as an Adsorbent for Chromium Determination in Wastewater Samples by Solid Phase Extraction
A procedure using disposable pipette tips adapted for solid-phase extraction, known as DPX SPE, was used as an alternative way for the chromium determination in wastewater samples. DPX-SPE consists of a device which allows a dynamic contact between the sample and the solid-phase. A residue obtained from the processing of coffee beans, denominate coffee silve
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Use of Direct Aqueous Injection and Solid Phase Extraction Coupled with Hydrophilic Interaction Chromatography to Analyze Haloacetic Acids in Drinking Water Samples
In this study, two analytical methods were evaluated to determine haloacetic acids (HAAs) in drinking water samples. Direct aqueous injection (DAI) and solid phase extraction (SPE) were evaluated and determination was performed by liquid chromatography tandem mass spectrometry (LC-MS/MS) with a hydrophilic interaction chromatography (HILIC) analytical column
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Elemental Chalcogen (Se, S) in PEG-400 to the Synthesis of Seleno- and Thioflavones from 2-Chlorophenyl Ethynyl Ketone and Nucleophilic Species of Chalcogen
An alternative green method was developed for the synthesis of thio-and selenoflavones by the ring closure of 2-chlorophenyl ethynyl ketone with NaHY (Y = S, Se). These nucleophilic chalcogen species were generated in situ using NaBH4 to reduce the elemental chalcogen in the presence of polyethylene glycol-400 (PEG-400). The efficiency of this reaction is st
J. Braz. Chem. Soc.. Publicado em: 2021-08
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4. Solventes eutéticos naturais profundos (NADES) no preparo de amostras de rocha fosfática e suplemento mineral para determinação elementar por técnicas de plasma
Natural deep eutectic solvents (NADES) based on xylitol, citric acid, and malic acid were synthesized and used in ultrasound-assisted extraction (UAE) and heating-bath extraction of phosphate rock and mineral supplement samples. Arsenic, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, P and Zn were determined by inductively coupled plasma mass spectrometry (ICP-MS) and i
Quím. Nova. Publicado em: 2021-06
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5. Preparation of Poly(3-hydroxybutyrate-b-ε-caprolactone) by Reactive Extrusion and Production of Electrospun Fibrous Mats
Poly(3-hydroxybutyrate) (PHB) has been proposed to be a potential candidate to be used as biomaterial. However, its poor processability, high brittleness and rigidity have limited its applicability. Transesterification reactions with poly(ε-caprolactone) (PCL), one of the most promising biomedical materials, emerge as an attractive alternative to improve it
J. Braz. Chem. Soc.. Publicado em: 2021-02
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6. A Green Procedure Using Disposable Pipette Extraction to Determine Polycyclic Aromatic Sulfur Heterocycles in Water Samples and Solid Petrochemical Residues
A simple and efficient method using reduced amounts of solvents for the determination of polycyclic aromatic sulfur heterocycles (PASHs) in aqueous matrices from a lagoon and leachate solid waste from a petrochemical industry is proposed. The target analytes were previously concentrated using the disposable pipette extraction (DPX) technique applying gas chr
J. Braz. Chem. Soc.. Publicado em: 2021-02
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7. POLÍMERO DE IMPRESSÃO MOLECULAR PARA O TIACLOPRIDO: UMA INVESTIGAÇÃO TEÓRICA
Thiacloprid (TCP) is a synthetic insecticide, belonging to the class of neonicotinoids (NNCs), which present potential damages to the environment, biodiversity and human health, being necessary its constant monitoring. In this sense, molecularly imprinted polymers (MIPs) have been shown as an excellent alternative for the separation science, since they can r
Quím. Nova. Publicado em: 2020-12
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8. EXTRAÇÃO ASSISTIDA POR ULTRASSOM PARA DETERMINAÇÃO DE LIPÍDEOS EM ALIMENTOS: UM EXPERIMENTO DE LABORATÓRIO
The ultrasound-assisted extraction (UAE) is an alternative approach for the total lipid content determination in food samples. The high extraction efficiency, being less time-consuming and with the possibility of using less toxic solvents are the main advantages of UAE. It is, thus, an excellent alternative to be applied as a laboratory experiment for underg
Quím. Nova. Publicado em: 2020-09
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9. Tear down academic paywall during pandemic
Zinc hexacyanoferrate (ZnHCF) is a Prussian Blue analog and can be intercalated by both monovalent and divalent ions. ZnHCF/multi-walled carbon nanotube (MWCNT) film could be used as a cathode for zinc ions battery. Carbon nanotubes improved significantly the electrochemical performance of the electrode. It is described the preparation of ZnHCF/MWCNT films b
Braz. J. Biol.. Publicado em: 2020-09
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10. Zinc Hexacyanoferrate/Multi-Walled Carbon Nanotubes Films for Rechargeable Aqueous Batteries
Zinc hexacyanoferrate (ZnHCF) is a Prussian Blue analog and can be intercalated by both monovalent and divalent ions. ZnHCF/multi-walled carbon nanotube (MWCNT) film could be used as a cathode for zinc ions battery. Carbon nanotubes improved significantly the electrochemical performance of the electrode. It is described the preparation of ZnHCF/MWCNT films b
J. Braz. Chem. Soc.. Publicado em: 2020-09
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11. SEPARATION OF SULFUR-CONTAINING COMPOUNDS FROM DIESEL BY OXIDATION FOLLOWED BY SOLVENT EXTRACTION IN A SINGLE DROP COLUMN
Abstract Oxidative desulfurization (ODS) is an attractive complementary or alternative process for the hydrodesulfurization (HDS) process due to advantages such as mild operating conditions. In the ODS process, the sulfur-containing compounds are oxidized first to polar sulfoxide and sulfone products and then these polar compounds are separated using solvent
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
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12. Coupled monolithic columns as an alternative for the use of viscous ethanol–water mobile phases on chromatographic fingerprinting complex samples
ABSTRACT Concepts of sustainability have received attention from people involved in investigation of nature-derived matrices. The effects of concomitant pollutant activities are cumulative and harmful to the environment from which these matrices are obtained. High performance liquid chromatography analyses generate millions of litters of chemical waste world
Rev. bras. farmacogn.. Publicado em: 2018-06