Chromatograph
Mostrando 1-12 de 145 artigos, teses e dissertações.
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1. Lipid Profile of Human Milk in Different Lactation Stages Submitted to Pasteurization, Lyophilization and Spray-Drying Processes
The objective of this study was to evaluate the effect of pasteurization, lyophilization and spray-drying on the lipid profile of donated human milk (DHM) at different lactation stages. Nine frozen samples of colostrum, transitional and raw mature human milk (HM) were collected from the Human Milk Bank (HMB) of the Hospital Universitário de Maringá (HUM).
Journal of the Brazilian Chemical Society. Publicado em: 2023
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2. Fast Catalytic Pyrolysis of Tetradecanoic Acid: Formation of Ketones as Intermediate Compounds in the Production of Hydrocarbons
This work aimed to compare two different catalysts in the production of a long chain ketone, intermediate in the production of hydrocarbons, during pyrolysis of tetradecanoic acid as a model fatty acid. The studied variables were the temperature, 450 and 600 ºC, and catalysts, γ-Al2O3 and Nb2O5, the latter has never been studied under such conditions. Pyro
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Identifying olive oil fraud and adulteration using machine learning algorithms
As olive oil (OO) is more expensive than other vegetable oils, it is usually adulterated by blending it with more economic edible oils such as cottonseed oil (CSO), canola oil (CO), and soybean oil (SO). This research aimed to determine the fatty acid compositions obtained as a result of blending different proportions of CSO, CO and SO with OO using a gas ch
Química Nova. Publicado em: 2022
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4. Thermal and Catalytic Fast Pyrolysis of Oily Extracts of Microalgae: Production of Biokerosene
Three different microalgae species, Desmodesmus sp., Nannochloropsis oculata and Halamphora coffeaeformis were grown under controlled conditions. The resulting dry biomass was characterized by TG-DTA (thermogravimetry-differential thermal analysis) and extracted with three solvents having different polarities. The extracts gross mass yields varied from 2% us
J. Braz. Chem. Soc.. Publicado em: 2021-04
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5. Method for Cleaning Back-Produced Water from Polymer Flooding Operations to Determine Polymer Molar Mass Using Size-Exclusion Chromatography
One of the methods used by the oil industry to increase production is to inject water, containing polymer, into the reservoir. The viscosity of the aqueous solution is primarily responsible for the efficiency of this method, and is achieved using polymers with high molar mass. However, polymer degradation can occur during pumping and fluid displacement in th
J. Braz. Chem. Soc.. Publicado em: 2020-12
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6. OTIMIZAÇÃO DO PROCESSO NÃO INVASIVO E NÃO DESTRUTIVO DE EXTRAÇÃO E ANÁLISE DE METABÓLITOS VOLÁTEIS DE MAMÃO PAPAIA POR SPME-GC-MS
The analysis of volatiles is an alternative in the routine of quality control of fruits, since the volatile metabolites can change in the presence of microorganisms. A well-established method for extracting volatiles is the solid phase microextraction (SPME). This work aims to define some parameters (fiber coating, conditioning time and fiber exposure time)
Quím. Nova. Publicado em: 2020-09
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7. 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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8. Preference of Neoseiulus californicus (Acari: Phytoseiidae) for volatiles of Bt maize induced by multiple herbivory
ABSTRACT Plant indirect induced defenses against herbivores are characterized by the production of plant volatiles that to attract natural enemies. The objective of this study was to evaluate whether the attack of the two-spotted spider mite Tetranychus urticae or the multiple herbivory of T. urticae together with the fall armyworm Spodoptera frugiperda are
Rev. Bras. entomol.. Publicado em: 13/01/2020
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9. Composition in fatty acids of mature milk of nursing mothers
Resumo Objetivos: determinar a composição em ácidos graxos do leite maduro de nutrizes e sua distribuição segundo algumas variáveis maternas. Métodos: trata-se de um estudo epidemiológico observacional, transversal realizado a partir da avaliação do perfil de ácidos graxos do leite humano maduro. Amostras de leite materno maduro foram obtidas de
Rev. Bras. Saude Mater. Infant.. Publicado em: 13/01/2020
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10. Optimization of extraction process for efficient imino acids recovery and purification from low-value sea cucumber
Abstract For high recoveries and purities of L-proline (L-Pro) and L-hydroxyproline (L-Hyp) from the low-value sea cucumber Acaudina leucoprocta, the extraction process was systematically investigated and optimized. The results indicated that, in decoloration of A. leucoprocta hydrolysate, activated carbon powdered W660 was more suitable due to the low addit
Food Sci. Technol. Publicado em: 06/06/2019
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11. Zinc Ferrite Nanoparticles via Coprecipitation Modified Method: Glycerol as Structure Directing and Stabilizing Agent
Coprecipitation is one of the most practical methods used to synthesize ferrite nanoparticles. Fine characteristics of these materials can be improved by means of a series of modifications in the synthesis method. In this paper we present a study of influence of glycerol as structure directing and stabilizing agent in the synthesis of zinc ferrite nanopartic
J. Braz. Chem. Soc.. Publicado em: 2019-04
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12. Mimicking Ketonuria in the Ketogenesis Defect 3-Hydroxy-3-MethylglutarylCoenzyme A Lyase Deficiency: An Artefact in the Analysis of Urinary Organic Acids
Abstract 3-Hydroxy-3-methylglutaryl-coenzyme A lyase (HMGCL, HMGCL) deficiency is a rare inborn error of ketogenesis. Even if the ketogenic enzyme is fully disrupted, an elevated signal for the ketone body acetoacetic acid is a frequent observation in the analysis of urinary organic acids, at least if derivatization is performed by methylation. We provide an
J. inborn errors metab. screen.. Publicado em: 28/02/2019