Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Environ Sci Pollut Res Int ; 31(16): 24584-24598, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448772

RESUMO

Thin-film nanocomposite (TFN) forward osmosis (FO) membranes have attracted significant attention due to their potential for solving global water scarcity problems. In this study, we investigate the impact of titanium oxide (TiO2) and titanium oxide/reduced graphene (TiO2/rGO) additions on the performance of TFN-FO membranes, specifically focusing on water flux and reverse salt diffusion. Membranes with varying concentrations of TiO2 and TiO2/rGO were fabricated as interfacial polymerizing M-phenylenediamine (MPD) and benzenetricarbonyl tricholoride (TMC) monomers with TiO2 and its reduced graphene composites (TiO2/rGO). The TMC solution was supplemented with TiO2 and its reduced graphene composites (TiO2/rGO) to enhance FO performance and reverse solute flux. All MPD/TMC polyamide membranes are characterized using various techniques such as scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle measurements. The results demonstrate that incorporating TiO2/rGO into the membrane thin layer improves water flux and reduces reverse salt diffusion. In contrast to the TFC membrane (10.24 L m-2h-1 and 6.53 g/m2 h), higher water flux and higher reverse solute flux were detected in the case of TiO2and TiO2/rGO-merged TFC skin membranes (18.81 and 24.52 L m-2h-1 and 2.74 and 2.15 g/m2 h, respectively). The effects of TiO2 and TiO2/rGO stacking on the skin membrane and the performance of TiO2 and TiO2/rGO skin membranes have been thoroughly studied. Additionally, being investigated is the impact of draw solution concentration.


Assuntos
Grafite , Nanocompostos , Titânio , Água , Membranas Artificiais , Osmose , Cloreto de Sódio , Cloreto de Sódio na Dieta
2.
Sci Rep ; 13(1): 12863, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553364

RESUMO

The resulting antibiotic residue and organic chemicals from continuous climatic change, urbanization and increasing food demand have a detrimental impact on environmental and human health protection. So, we created a unique B, N-CQDs (Boron, Nitrogen doping carbon quantum dots) based fluorescent nanosensor to investigate novel sensing methodologies for the precise and concentrated identification of antibiotics and phenol derivatives substances to ensure that they are included in the permitted percentages. The as-prepared highly fluorescent B, N-CQDs had a limited range of sizes between 1 and 6 nm and average sizes of 2.5 nm in our study. The novel B, N-CQDs showed high sensitivity and selectivity for phenolic derivatives such as hydroquinone, resorcinol, and para aminophenol, as well as organic solvents such as hexane, with low detection limits of 0.05, 0.024, 0.032 and 0.013 µM respectively in an aqueous medium. The high fluorescence B, N-CQDs probes were examined using transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and UV/VIS spectroscopy. The outcomes were compared to carbon quantum dots (CQDs) previously generated from Urea.


Assuntos
Corantes Fluorescentes , Pontos Quânticos , Humanos , Corantes Fluorescentes/química , Carbono/química , Pontos Quânticos/química , Fenóis , Espectroscopia de Infravermelho com Transformada de Fourier , Nitrogênio/química
3.
ACS Omega ; 3(2): 1801-1814, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31458494

RESUMO

The synthesis of nitrogen, boron, and nitrogen-boron-codoped graphenes was attained via mixing solutions of GO with urea, boric acid, and a mixture of both, respectively, followed by drying in vacuum and annealing at 900 °C for 10 h. These materials were thoroughly characterized employing XRD, TEM, FTIR, Raman, UV-vis, XPS, IPCE%, and electrical conductivity measurements. The nitrogen-doped graphene (NG) showed an excellent supercapacitor performance with a higher specific capacitance (388 F·g-1 at 1 A·g-1), superior stability, and a higher power density of 0.260 kW kg-1. This was mainly due to the designated N types of doping and most importantly N-O bonds and to lowering charge transfer and equivalent series resistances. The NG also indicated the highest photocatalytic performance for methylene blue (MB 20 ppm, power = 160 W, λ > 420 nm) and phenol (5 ppm) degradation under visible light illumination with rate constants equal 0.013 min-1 and 0.04 min-1, respectively. The photodegradation mechanism was proposed via determining the energy band potentials using the Mott-Schottky measurements. This determined that photoactivity enhancement of the NG is accounted for by acquisition of nitrogen-oxy-carbide phases that shared in inducing a higher IPCE% (60%) and a lower band gap value (1.68 eV) compared to boron and nitrogen-boron-codoped graphenes. The achieved photodegradation mechanism relied on scavengers performance suggesting that •OH and electrons were the main reactive species responsible for the MB photodegradation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...