S Matrices
Mostrando 1-12 de 227 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. 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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3. 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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4. 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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5. 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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6. 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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7. 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
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8. 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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9. o-DGT Devices for the Determination of Emerging Contaminants in Aqueous Matrices
Samplers based on the diffusive gradients in thin films for organics (o-DGT) were developed and applied in Brazilian aqueous matrices for the determination of four emerging contaminants (EC): 4-octylphenol, 4-nonylphenol, triclosan, and bisphenol A. The OASIS HLB resin used as the binding phase presented a high sorption capacity and the extraction associated
J. Braz. Chem. Soc.. Publicado em: 2021-01
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10. BIONANOCOMPÓSITOS POLIMÉRICOS À BASE DE MONTMORILLONITA – MATERIAIS DE INTERESSE CONTÍNUO
Polymeric bionanocomposites are versatile materials that have many practical applications. The wide use of these materials is mainly due to their structure and properties, which combine at nanometric scale, the functionality of biopolymers with the excellent stability of inorganic solids, such as the clay minerals family. Montmorillonite is the most widely e
Quím. Nova. Publicado em: 2020-12
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11. Blue-Emitting MWO4:Tm3+ (M: Sr, Ba) Phosphors Prepared by Coprecipitation Method at Room Temperature
MWO4 host matrices (M: Sr, Ba) doped with different Tm3+ concentrations (0.02, 0.04, 0.06, 0.08 and 0.10 mol%) have been successfully prepared by the coprecipitation method at room temperature. The as-prepared nanophosphors were characterized by infrared spectroscopy showing intense absorption bands in the range of 700-1000 cm-1 attributed to the symmetrical
J. Braz. Chem. Soc.. Publicado em: 2020-11
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12. Matrix Effects on the Degradation of Gemfibrozil, Hydrochlorothiazide, and Naproxen by Heterogeneous Photocatalysis
The degradation of a pharmaceutical mixture (gemfibrozil, hydrochlorothiazide and naproxen) by TiO2/UV-A in different aqueous matrices was evaluated. The matrix components affected the operational conditions, rate constants, and removal efficiency of the pharmaceuticals, as well as toxicity. For sewage treatment plant effluent, a TiO2 concentration three-fol
J. Braz. Chem. Soc.. Publicado em: 2020-06