Extraction Separation
Mostrando 1-12 de 356 artigos, teses e dissertações.
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1. What is new in non-chromatographic flavonoid purification?
Flavonoids are metabolites occurring in all plant tissues and present different biological activities. They occur in a mixture of similar polarity with laborious separation and purification processes, usually furnishing low yields. Semi-preparative chromatographic methods are universally employed procedures for their isolation. This paper discusses the state
Química Nova. Publicado em: 2022
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2. Phytocomponents, Evaluation of Anticholinesterase Activity and Toxicity of Hydroethanolic Extracts of Parkia platycephala Benth.
This study evaluated the chemical composition, antioxidant and anticholinesterase activities, and the toxicity of hydroethanolic extracts of the Parkia platycephala Benth. Hot extraction with 70% hydroethanolic solution was used to obtain crude extracts of the leaf (LE), bark (BE), flower (FE), and seed (SE). Separation and identification of the compounds we
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. 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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4. Zeolite-SPION Nanocomposite for Ammonium and Heavy Metals Removal from Wastewater
Minimizing the emission of industrial effluents and realizing the recovery/extraction of key elements such as the rare earths from low concentration solutions, or during water decontamination processes, are some of the biggest challenges of modern society. Accordingly, the preparation and characterization of a low cost recyclable and reusable superparamagnet
J. Braz. Chem. Soc.. Publicado em: 2020-11
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5. A SALTING-OUT ASSISTED LIQUID-LIQUID EXTRACTION FOR THE DETERMINATION OF TEBUCONAZOLE, CARBOFURAN AND IMIDACLOPRID IN WHITE AND ROSÉ WINES
Food safety is a constant and necessary concern due to the worldwide increase of the food demand. The monitoring of quality parameters demands the development of accurate, easy and fast procedures. The aim of this work was to develop a cheap, miniaturized and trustworthy salting-out assisted liquid-liquid extraction (SALLE) procedure for the determination of
Quím. Nova. Publicado em: 20/07/2020
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6. PROCESSING OF A METAL CONCENTRATE FROM GROUND WASTE PRINTED CIRCUIT BOARDS IN ACIDIC MEDIA USING HYDROGEN PEROXIDE AS OXIDANT
The recovery of precious and base metals of a metal concentrate from ground waste printed circuit boards (PCBs) is described in detail. Samples were treated with NaOHaq. to remove the soldering mask. Experiments were performed in acidic medium (HF, H2SO4, CH3COOH or H3PO4) using H2O2 as oxidant. Base metals were leached in high yields (>99 wt.%) at ~40 ºC a
Quím. Nova. Publicado em: 20/07/2020
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7. A Choline Chloride-Ethylene Glycol Deep Eutectic Solvent Based on Magnetic Polydopamine with Preconcentration and Determination for Sulfonylurea Herbicides in Water Samples
In this study, a novel deep eutectic solvent (DES) containing choline chloride and ethylene glycol was synthesized, and the magnetic polydopamine (PDA) was modified with this deep eutectic solvent to form Fe3O4@PDA-DES. Fourier transformed infrared spectroscopy, scanning electron microscopy, and vibrating sample magnetometer were used to characterize the pro
J. Braz. Chem. Soc.. Publicado em: 2020-07
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8. SEQUÊNCIA DIDÁTICA PARA A PROMOÇÃO DE ESTUDO PRÁTICO E MULTIDISCIPLINAR COM MATERIAIS ACESSÍVEIS
Innovation and multidisciplinarity are the way to accelerate improvements in education, as well as the search for contextualized content. The multidisciplinarity between chemistry and Biology, allows to explore various contents, one of them is the environment. Works that offer alternatives to simpler experiments are of great help professors. In this context,
Quím. Nova. Publicado em: 2020-05
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9. Fast and Ecological Liquid-Liquid Separation Method for Preparing Quinones Enriched Extract from Nigella sativa Oil
A fast, inexpensive, and ecological method based on liquid-liquid extraction principle has been developed for preparation of extract with high content of Nigella sativa (N. sativa) quinones. The gas chromatography-mass spectrometry (GC-MS) analysis showed that oil extraction using 70% ethanol for 6 h yielded extract containing 50% of thymoquinone (TQ) and 13
J. Braz. Chem. Soc.. Publicado em: 2020-04
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10. Determinação de docetaxel e metabólitos em plasma por UPLC-MS/MS: desenvolvimento de metodologia analítica e aplicação clínica
A highly sensitive ultra-performance liquid chromatography tandem mass spectrometry method for the determination of Docetaxel and metabolites (M1+M3) in human plasma samples was developed and validated. The method employs a liquid-liquid extraction and a reversed phase separation Acquity® C18 column BEH C18 (150 x 2.1 mm, 1.7 µm). Mobile phase was a mixtur
Quím. Nova. Publicado em: 2020-04
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11. Separation of gadolinium and europium from chloride media by the solvent extraction technique
Abstract Obtaining rare earth elements (REE) is a complicated task, due mainly to the difficulty of separating and purifying them. Solvent extraction is the most widely used technique for separating REE, and the most common extractants used are organophosphorus acids. The low selectivity of this technique leads to the need for a high number of extraction cel
REM, Int. Eng. J.. Publicado em: 2020-03
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12. COMPARISON OF ARROWROOT (Maranta arundinacea) AND CASSAVA STARCH EXTRACTION IN SEPARATION, CONCENTRATION, AND PURIFICATION USING A ROTATING SIEVE UNDER WATER
ABSTRACT Brazil is home to several plant species that exhibit potential for starch extraction. The arrowroot plant stands out owing to its South American origin. Arrowroot starch is especially important for fine confectionery, which is a high-value niche market. Thus, a small producer could benefit from the high prices of arrowroot starch. However, to have c
Eng. Agríc.. Publicado em: 2020-02