Matrices
Mostrando 1-12 de 1311 artigos, teses e dissertações.
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1. ON A NEW APPROACH TO PEIRCE’S THREE-VALUE PROPOSITIONAL LOGIC
Abstract In 1909, Peirce recorded in a few pages of his logic notebook some experiments with matrices for three-valued propositional logic. These notes are today recognized as one of the first attempts to create non-classical formal systems. However, besides the articles published by Turquette in the 1970s and 1980s, very little progress has been made toward
Manuscrito. Publicado em: 2022
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2. Microplastics in Latin America Ecosystems: A Critical Review of the Current Stage and Research Needs
The ubiquity of microplastics ecosystems has gained global attention. In this context, Latin America, which is responsible for 8% of the world’s consumption of plastic material and has a small recycling rate (4.5%), does not have enough data on microplastics contamination in its environmental matrices. This systematic review analyzed 196 studies from 16 te
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. ANALYSIS OF BENZODIAZEPINES IN PLASMA SAMPLES BY DLLME AND LC-DAD: CRITICAL ASPECTS, FLAWS AND ISSUES ENCOUNTERED - A DISCUSSION
Dispersive liquid-liquid microextraction (DLLME) is a fast and simple technique and applicable procedure for the analysis of xenobiotics in different biological matrices. We have developed a DLLME method for the determination of benzodiazepines in plasma samples using liquid chromatography-diode-array detection (LC-DAD). During method validation, relative st
Química Nova. Publicado em: 2022
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4. The BigFLUX Magnetic Matrix Technology
Abstract The Magnetic separation of ultra-fine ore particles has always posed a challenge to the JONES/WHIMS process. Despite many advances in this technology, no effective improvement has been made to its core component: The Magnetic Matrix. The current approach to separate ultra-fine particles teaches that the gap of the matrix and its teeth size must be s
REM - International Engineering Journal. Publicado em: 2022
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5. A Rational Procedure to Increase Selectivity in the Determination of an Elicitor as Salicylic Acid in Polygala Extracts Using Capillary Electrophoresis
Considering the economic potential of secondary metabolites, researches have been focusing several strategies in order to explore and enhance the accumulation of these metabolites in plant matrices in a broad context. One of those strategies is the development of suitable methodologies for the determination of some elicitors, such as salicylic acid (SA). Sin
Journal of the Brazilian Chemical Society. Publicado em: 2022
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6. Development and application of a test mixture for untargeted liquid chromatography-mass spectrometry analysis of urine samples
Metabolic profiling of complex biological matrices based on liquid chromatography-mass spectrometry (LC-MS) allows detecting a wide range of metabolites with distinct concentrations and physicochemical properties. Given the complexity of samples and the necessity of a comprehensive approach in untargeted metabolomics, quality control strategies are mandatory
Química Nova. Publicado em: 2022
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7. Epistemological Possibilities of Public Administration Theories: from Paradigms to Epistemic Matrices
Resumo O objetivo deste trabalho é contribuir com a literatura sobre administração pública ao realizar um estudo epistemológico das principais correntes do campo, atualizando-as com o Círculo das Matrizes Epistêmicas proposto por Paes de Paula (2016) . Para isso, (a) parte-se do ensaio realizado por Andion (2012) , que realiza um estudo crítico sobre
Organizações & Sociedade. Publicado em: 2022
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8. Cascade Modeling of the Measuring System Used to Assess S-Parameters of Anchor Rods on Power Transmission Lines Guyed Towers
Abstract The structural condition of the cable-stayed towers anchorage on power transmission lines requires constant monitoring. Maintenance routines must be able to identify faulty anchor rods and substitute them to avoid tower collapses and power delivery interruptions. Modern statistical diagnostic systems based on machine learning requires the generation
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
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9. Development of a TD-NMR Method to Monitor Brazil Nuts Oil Content: A Green and Low-Cost Based Approach
Growth in the international popularity of Brazil nuts oil (Bertholletia excelsa, Bonpl.) has demanded a closer look at quality aspects of the nuts. In this context, time-domain 1H nuclear magnetic resonance spectroscopy (TD-NMR) can be a useful tool for assessing the lipid portion of such matrices. In this work, a TD-NMR method was developed and validated to
J. Braz. Chem. Soc.. Publicado em: 2021-07
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10. Acid matrix production from treated natural vermiculite-hydrobiotite
Abstract Given the potential of acid-activated clays in adsorptive and catalytic processes, several studies focusing on acid matrices have grown over the years, making it possible to study vermiculite, a mineral composed of a type 2:1 unit cell with tetrahedral and octahedral sheets. Therefore, this work aimed to study vermiculite treated with acids for the
Cerâmica. Publicado em: 2021-06
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11. 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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12. Study of Crystallization and Composition on Silicon Oxycarbide (SiOC) and Silicon Boron Oxycarbide (SiBOC) Ceramics Obtained from Alkoxysilanes Precursors
This work deals on the preparation of silicon oxycarbide (SiOC) and silicon boron oxycarbide (SiBOC) ceramics from pyrolysis involving alkoxysilanes with different organic groups. Boron content, organic substituent and annealing time were evaluated on crystallization and composition of resulting ceramics. B-free precursors composed of methyltriethoxysilane (
J. Braz. Chem. Soc.. Publicado em: 2021-06