Optical Emission
Mostrando 1-12 de 396 artigos, teses e dissertações.
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1. Synthesis and characterization of α-SnWO4 powders obtained by microwave-assisted hydrothermal method
Abstract The structural, morphological, and optical properties of α-SnWO4 synthesized by microwave-assisted hydrothermal method at 150 °C for different times were investigated. XRD revealed the formation of the orthorhombic phase, without the presence of a secondary phase. The sample processed for 64 min showed a reduction in unit cell volume, suggesting a
Cerâmica. Publicado em: 2022
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2. Quantification of Carbon Dioxide (CO2), Methane (CH4), and Nitrous Oxide (N2O) Using Near Infrared Spectroscopy and Multivariate Calibration in High Humidity Levels
In this work we developed a promising analytical method combining Fourier transform near-infrared (FT-NIR) spectroscopic technique and first-order multivariate calibration using partial least-squares (PLS) model to simultaneously quantify the main greenhouse gases (GHG’s): methane (CH4), carbon dioxide (CO2), nitrous oxide (N2O) and water vapor (H2O). The
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. AVALIAÇÃO DE METAIS POTENCIALMENTE TÓXICOS EM CHORUME PROVENIENTE DE ÁREA DE DEPOSIÇÃO DE RESÍDUOS SÓLIDOS EM BELÉM - PARÁ
The formation of solid waste is a global challenge regarding environmental preservation. Due to the lifestyle of modern society, which aims to improve practicality, new products are constantly being released in the market and increasing the formation of waste. The decomposition of waste from various origins produces a dark liquid named leachate, which presen
Química Nova. Publicado em: 2022
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4. Preparation of SAPO-34-Based Catalyst for Conversion of Fructose to 5-Hydroxymethylfurfural
Solid acid-catalyzed dehydration of fructose to produce 5-hydroxymethylfurfural (5-HMF) has been a hotspot in biomass conversion research in recent years. In this study, a novel SAPO-34-based catalyst was prepared by consecutive steps of titanium doping, sulfuric acid impregnation, and sulfonic acid functionalization. Characterization of the catalyst with X-
J. Braz. Chem. Soc.. Publicado em: 2021-08
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5. Development of Analytical Method for Determination of Inorganic Constituents in Powder Refreshment Using Dilute Mineral Acids and Detection by ICP OES
An analytical method for multi-elementary determination in powder refreshment, based on sample digestion using dilute mineral acids and detection by inductively plasma coupled optical emission spectrometry (ICP OES) is proposed. Chemometric tools, such as fractional factorial design and principal component analysis (PCA) and hierarchical cluster analysis (HC
J. Braz. Chem. Soc.. Publicado em: 2021-07
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6. Development of a Simple and Fast Procedure Based on Acid Dilution for Determination of Macro and Microelements in Guarana-Based Beverages by ICP OES
A simple analytical procedure is proposed for the direct analysis of guarana-based beverages in order to determine nutrient elements by inductively coupled plasma optical emission spectrometry (ICP OES). A Box-Behnken design, combined with Derringer’s desirability function, was applied to the simultaneous optimization of the ICP OES radiofrequency (RF), sa
J. Braz. Chem. Soc.. Publicado em: 2021-07
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7. Oral Use of Phenytoin to Reduce Calcification in Bovine Pericardium and Porcine Aortic Leaflets Implants in Rats
Abstract Introduction: This study aims to test the effect of phenytoin as an inhibitor of the process of dystrophic calcification in bovine pericardium and porcine leaflets implanted in the subcutaneous tissue of rats. Methods: Isolated segments of biomaterials were implanted subcutaneously in young rats. The study groups received 500 mg phenytoin per kilo
Braz. J. Cardiovasc. Surg.. Publicado em: 2021-06
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8. 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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9. Alternative Approaches Applied to Inductively Coupled Plasma Techniques: Multi-Flow and Two-Flow Calibration
Multi-flow calibration (MFC) is based on monitoring the analytical signal from a single calibration standard solution at several different nebulization gas flow rates (Q), which normalizes plasma conditions and minimizes matrix effects. In the present study, MFC was evaluated, for the first time, applied to inductively coupled plasma optical emission spectro
J. Braz. Chem. Soc.. Publicado em: 2021-04
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10. Sample Preparation Using TMAH and Nitric Acid for Multielement Determination in Crustacean Samples by MIP OES
This study proposes a simple sample preparation procedure using tetramethylammonium hydroxide (TMAH) and nitric acid (HNO3) to determine Cr, Cu, Fe, K, Mg, Mn, and Zn concentrations in shrimp (Macrobrachium amazonicum) and crab (Ucides cordatus) samples from the Amazon region by microwave-induced plasma optical emission spectrometry (MIP OES). The sample sol
J. Braz. Chem. Soc.. Publicado em: 2021-03
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11. Impact of Continuing Education on the Quality of Blood Pressure Measurement
The properties of lanthanides allow them to be used as contrast agents for magnetic resonance imaging, thereby helping to differentiate between tissues, organs, and pathologies more efficiently. Lanthanides contain thermosensitive energy levels that aid identification of cancer and healthy cells. This work investigates the GdVO4 matrix obtained by the non-hy
Int. J. Cardiovasc. Sci.. Publicado em: 2021-02
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12. Er3+/Yb3+-Doped GdVO4 Obtained by the Non-Hydrolytic Sol-Gel Route and Potential Application as Up-Conversion Thermometer
The properties of lanthanides allow them to be used as contrast agents for magnetic resonance imaging, thereby helping to differentiate between tissues, organs, and pathologies more efficiently. Lanthanides contain thermosensitive energy levels that aid identification of cancer and healthy cells. This work investigates the GdVO4 matrix obtained by the non-hy
J. Braz. Chem. Soc.. Publicado em: 2021-02