Detector
Mostrando 1-12 de 1623 artigos, teses e dissertações.
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1. Carbon Dots from Pilosocereus gounellei for Fluorimetric Determination of Tannin in Tea Using a Flow-Batch System
In this study, xiquexique (Pilosocereus gounellei) native endemic cactus from the Brazilian semiarid was used for the first time as a natural carbon source (“green precursor”) for the synthesis of highly fluorescent carbon dots (CDs). These CDs were successfully used to develop a fast, low-cost, eco-friendly fluorescence method for the determination of t
Journal of the Brazilian Chemical Society. Publicado em: 2023
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2. 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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3. Innovative gas chromatographic determination of formaldehyde by miniaturized extraction and on-fiber derivatization, via SPME and SPME Arrow
Formaldehyde (FA) is a carbonyl compound, ubiquitous in the environment and among the most widespread pollutants: it has exhibited toxic properties and is classified as a human carcinogen. FA is released from several sources, both temporary (e.g., combustion processes) and permanent (e.g., building products). This work proposes an innovative fully-automated
Química Nova. Publicado em: 2022
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4. A Physical Study to Explain Response Differences between the BID and FID Detectors for PAHs and Pesticides
The dielectric barrier discharge ionization detector (BID) is one of the most modern detectors commercially available for gas chromatography (GC). Its technology based on the sample ionization through the energy released from the helium plasma generation process gives it the ability to act as a universal detector and a greater response to various types of co
Journal of the Brazilian Chemical Society. Publicado em: 2022
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5. Response Factor in GC-FID Methyl Ester Analysis in Several Biodiesels: A Comparative Study of the EN 14103:2011 and ABNT 15764:2015 Methods versus a Proposed GC-FID Procedure for Individual Ester Determination
A gas chromatography method with a flame ionization detector enabled by relative response factor was developed to determine the individual and the total content of esters in biodiesel. This method accounts for different response factors of the detector for a homologous series of esters that may be present in biodiesel. In this way, the determination of the t
Journal of the Brazilian Chemical Society. Publicado em: 2022
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6. TANINOS E FLAVONOIDES DAS FLORES DE EUGENIA UNIFLORA (MYRTACEAE)
Eugenia uniflora, popularly known as pitanga, is a native species of the Brazilian flora, widely used in folk medicine for the treatment of various diseases and which has several bioactive chemical constituents. The aim of this work was to analyze the chemical composition of flowers visited by bees from Eugenia uniflora by Ultra-Performance Liquid Chromatogr
Química Nova. Publicado em: 2022
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7. 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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8. CARDIOVASCULAR RESPONSE IN MID AND LONG-DISTANCE RUNNERS UNDER TRAINING
RESUMO Introdução: A pesquisa dos efeitos do exercício sobre o sistema cardiovascular tem uma longa história que recentemente foi expandida com o uso da ecocardiografia. Pesquisas utilizando a ecocardiografia por doppler têm crescido devido ao método de exame apresentar-se seguro e não-invasivo para estudo de morfologia e função cardíaca. Porém a
Revista Brasileira de Medicina do Esporte. Publicado em: 2022
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9. AN ADAPTED UNMANNED AERIAL VEHICLE FOR ENVIRONMENTAL WATER SAMPLING
In this work an unmanned aerial vehicle (UAV) was adapted to be used as an environmental tool to collect water samples of sea, estuary, and mangrove for further analysis by gas chromatography with a mass detector (GC-MS). The sampling automated system was based on a microcontroller, a solenoid valve, and a peristaltic mini-pump that was coupled to a quadcopt
Química Nova. Publicado em: 2022
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10. Subclinical Systolic Dysfunction during Chemotherapy for Breast Cancer
Abstract Background Cardiotoxicity is the main complication related to cancer therapy. Studies indicate that global longitudinal strain is an early detector of subclinical dysfunction of the left ventricle, preceding the decline in ejection fraction (EF). However, the reproducibility of such methodology has not been tested outside specialized centers. Obj
International Journal of Cardiovascular Sciences. Publicado em: 2022
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11. Bioacumulação comparativa de HAP e BTEX em Malapterurus electricus (Siluriformes: Malapteruridae) e seu parasita entérico, Electrotaenia malopteruri, coletado na lagoa Lekki, Lagos, Nigéria
Resumo A contaminação da lagoa Lekki por produtos químicos petrogênicos, como hidrocarbonetos aromáticos policíclicos (HAP) e benzeno, tolueno, etilbenzeno e xileno (BTEX), foi amplamente relatada. O estudo teve como objetivo investigar a bioacumulação de HAP e BTEX em Malapterurus electricus, coletados na lagoa Lekki, em Lagos, Nigéria. O BTEX foi
Braz. J. Biol.. Publicado em: 2021-12
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12. Bioacumulação de pesticidas organoclorados, infecções por Procamallanus sp. (Baylis, 1923) e colonização microbiana em peixes africanos Snakehead coletados na lagoa Lekki, Lagos, Nigéria
Resumo O aumento exponencial da população nigeriana exigiu o uso de agroquímicos para aumentar a produção agrícola e, assim, atender à crescente demanda por alimentos. No entanto, agroquímicos como pesticidas organoclorados (OCPs) causaram vários problemas de saúde e ecológicos. Portanto, o estudo teve como objetivo avaliar a bioacumulação de OC
Braz. J. Biol.. Publicado em: 2021-12