Carbon Analysis
Mostrando 1-12 de 2205 artigos, teses e dissertações.
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1. Study of nanocomposites with carbon nanotubes and their tendency for carbon organization
Abstract The carbon derived from the thermal treatment of modified phenolic resins (PR) tends to organize into graphitic lamellae or turbostratic carbon and is commonly considered non-graphitizable. In this study, nanocomposites were synthesized with modified phenolic resin (Novolac) used as the matrix and oxidized multi-walled carbon nanotubes (NTox) in amo
Cerâmica. Publicado em: 2022
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2. Spectrofluorimetric Determination of Hydrochlorothiazide by a Carbon Dots-Based Probe via Inner Filtering Effect and Resonance Rayleigh Scattering
Synthesis of carbon dots (CDs) from natural resources not only enables green synthesis and production of environmentally friendly materials, but also provides a cost-effective probe as a fluorescence nanosensor. The proposed sensor introduces a unique one-pot hydrothermal CDs synthesis from alfalfa leaves, which is promising for sensing hydrochlorothiazide (
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. GRAPHEN-PHENYL-NH2 AS NANOCARRIER: A DENSITY FUNCTIONAL THEORY STUDY
Recently, graphene and modified graphene as one of the most suitable and the most important carbon nanomaterials have been introduced for drug delivery. In this paper, we have studied the binding characteristics of the EDC-NHS cross-linking process of graphene-phenyl-NH2 and 5-aminolevulinic acid (ALA) drug in both gas and solvent phases by density functiona
Química Nova. Publicado em: 2022
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4. An alternative energy generation from charcoal produced from Brazilian pine (Araucaria angustifolia (Bert.) O. Ktze) seed residues
The perspective is that the energy demand will grow in the coming decades worldwide. The search for renewable energy sources is urgent and necessary. Residual biomass may be a promising source of raw material for obtaining bioenergy. Thus, this research sought to evaluate the energetic and physicochemical properties of residues from the seeds of Brazilian pi
Química Nova. Publicado em: 2022
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5. Spectroscopic techniques combined with chemometrics to study organic matter in tropical soils with different degrees of pedogenetic evolution
Understanding of the organomineral interactions in soil can elucidate the humic substances (HS) formation and the humification process. This study aimed to structurally characterize the humic acids (HA) formed in tropical soils with different pedogenesis degrees. The HA fraction was extracted from soil samples in the superficial horizons of an Inceptisol and
Química Nova. Publicado em: 2022
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6. Additive Manufacturing towards the Fabrication of Greener Electrochemical Sensors for Antioxidants
Additive manufacturing is an emerging tool that has contributed to the sustainable fabrication of devices in several areas based on the concept of “zero waste”. Considering extrusion-based manufacturing (or 3D printing), polylactic acid (PLA) has been highlighted due to its biodegradability, obtention from renewable sources, and compatibility for 3D prin
Journal of the Brazilian Chemical Society. Publicado em: 2022
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7. A novel fluorescence sensor for the detection of chloride ion in artificial sweat and environmental water with nitrogen-doped graphene quantum dots
A new fluorescent detection route for chloride ion was designed with Nitrogen-doped graphene quantum dots (N-GQDs), which were prepared by a traditional hydrothermal method with citric acid as carbon source and urea as nitrogen source. The prepared N-GQDs solution was light yellow, and the freeze-dried solid was black. It emitted blue light under ultraviolet
Química Nova. Publicado em: 2022
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8. Multifractal and joint multifractal analysis of soil invertebrate fauna, altitude, and organic carbon
RESUMO Os objetivos deste estudo foram avaliar o grau de multifractalidade da distribuição espacial da altitude, concentração de carbono orgânico e diversidade da fauna de invertebrados, e caracterizar o grau de associação joint multifractal dessas variáveis. A amostragem do solo foi realizada a cada 20 m em um transecto de 2.540 m, totalizando 128 p
Revista Brasileira de Engenharia Agrícola e Ambiental. Publicado em: 2022
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9. Prone ventilation in intubated COVID-19 patients: a systematic review and meta-analysis
Abstract Background The efficacy and safety profiles of prone ventilation among intubated Coronavirus Disease 2019 (COVID-19) patients remain unclear. The primary objective was to examine the effect of prone ventilation on the ratio of arterial partial pressure of oxygen to fraction of inspired oxygen (PaO2/FiO2) in intubated COVID-19 patients. Methods Dat
Brazilian Journal of Anesthesiology. Publicado em: 2022
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10. Photo-Fenton-Based Degradation of Methylene Blue Dye Using Hydroxyapatite Nanoparticles Doped with Fe3O4/γ-Fe2O3
In this study, we evaluated the catalytic properties of hydroxyapatite (HA) nanoparticles (NPs) doped with Fe3O4/γ-Fe2O3 for the degradation of methylene blue (MB) dye using a photo-Fenton process at pH 2.5, 7.0, and 9.0. The HA NPs were characterized using X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectrometry, Raman spect
Journal of the Brazilian Chemical Society. Publicado em: 2022
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11. Fundamental bioflotation aspects of hematite using an extracted Rhodococcus opacus by-product
Abstract The aim of this study is to assess the floatability of hematite using a crude biosurfactant (BS) extracted from Rhodococcus opacus. Throughout high-pressure ethanol extraction, unrefined surfactant was extracted from the bacteria with a yield of 0.3 g/L. An FTIR analysis on this extract, shows the presence of alcohol (–OH) and ketone (C=O) groups,
REM, Int. Eng. J.. Publicado em: 2021-09
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12. Synergy between Experimental and Theoretical Investigations Reveals the Anti‑Corrosion Efficiency of Imine-Chalcones
The inhibitory action of three imine-chalcones on carbon steel corrosion in HCl was investigated by theoretical and experimental methods. Quantum descriptors were calculated at the conductor-like polarizable continuum model (CPCM)-Becke-3 Parameter-Lee-Yang-Parr (B3LYP)-D3/def2-TZVPP level allowing the prediction of efficiency inhibition ranking. Electrochem
J. Braz. Chem. Soc.. Publicado em: 2021-08