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1.
Environ Res ; 244: 117964, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38135102

RESUMO

In this study, we evaluate the efficiency of two novel nanostructured adsorbents - chitosan-graphitic carbon nitride@magnetite (CS-g-CN@Fe3O4) and graphitic carbon nitride@copper/zinc nanocomposite (g-CN@Cu/Zn NC) - for the rapid removal of methylparaben (MPB) from water. Our characterization methods, aimed at understanding the adsorbents' structures and surface areas, informed our systematic examination of influential parameters including sonication time, adsorbent dosage, initial MPB concentration, and temperature. We applied advanced modeling techniques, such as response surface methodology (RSM), generalized regression neural network (GRNN), and radial basis function neural network (RBFNN), to evaluate the adsorption process. The adsorbents proved highly effective, achieving maximum adsorption capacities of 255 mg g-1 for CS-g-CN@Fe3O4 and 218 mg g-1 for g-CN@Cu/Zn NC. Through genetic algorithm (GA) optimization, we identified the optimal conditions for the highest MPB removal efficiency: a sonication period of 12.00 min and an adsorbent dose of 0.010 g for CS-g-CN@Fe3O4 NC, with an MPB concentration of 17.20 mg L-1 at 42.85 °C; and a sonication time of 10.25 min and a 0.011 g dose for g-CN@Cu/Zn NC, with an MPB concentration of 13.45 mg L-1 at 36.50 °C. The predictive accuracy of the RBFNN and GRNN models was confirmed to be satisfactory. Our findings demonstrate the significant capabilities of these synthesized adsorbents in effectively removing MPB from water, paving the way for optimized applications in water purification.


Assuntos
Grafite , Compostos de Nitrogênio , Parabenos , Poluentes Químicos da Água , Purificação da Água , Cobre/química , Temperatura , Água/química , Adsorção , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio , Purificação da Água/métodos
2.
Phys Chem Chem Phys ; 24(11): 6639-6654, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35234754

RESUMO

The competitive aggregated adsorption and molecular interactions between paclitaxel (PX) and mitomycin C (MMC) molecules on the surface of boron nitride nanosheets (BNNSs) were investigated using a molecular dynamics method. The potential capability of BNNSs to immobilize PX and MMC molecules was examined in detail. Structural parameters such as the radius of gyration of the drugs on the considered surface were calculated. The results indicate rapid and efficient adsorption of PX and MMC ligands onto BNNSs. The electrostatic contribution confirms the efficient self-aggregation of each drug onto the BNNS surface during the adsorption process in 100 ns simulation trajectories. The radial distribution function and dipole moments of water molecules have been considered to estimate the effect of water molecules on the adsorption of PX and MMC ligands onto BNNSs. The aggregation of MMC molecules onto BNNSs does not affect the aggregated adsorption of PX molecules. The maximum values of interaction energies and hydrogen bonds for PX molecules indicate that PX molecules overtake MMC molecules via competitive aggregation. The efficient and favorable delivery capability of boron nitride nanosheets to adsorb and deliver self-aggregated PX and MMC molecules has been revealed by molecular dynamics simulation results.


Assuntos
Antineoplásicos , Nanopartículas , Adsorção , Compostos de Boro/química , Mitomicina , Simulação de Dinâmica Molecular , Nanopartículas/química , Paclitaxel
3.
J Mol Model ; 29(11): 333, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37807012

RESUMO

CONTEXT: The aggregation and adsorption of amantadine and sodium dodecyl sulfate on the boron nitride nanotubes in aqueous system were investigated, employing the classical molecular dynamics method. The aqueous system containing amantadine and sodium dodecyl sulfate was investigated by self-diffusion of the molecules, with particular emphasis on their center of mass mean square displacement. The radial distribution function and dipole moment measurement were used to analyze the water effect on the aggregation and molecular interaction between amantadine and sodium dodecyl sulfate in the complex. In turn, the amantadine molecules are able to develop water monolayers at the aqueous solution but show no noticeable aggregated adsorption in the fluid. In contrast, sodium dodecyl sulfate self-aggregation on the boron nitride nanotube efficiently occurs, and so the effect of sodium dodecyl sulfate on aggregated adsorption of amantadine was studied. Our results show that in the presence of sodium dodecyl sulfate at critical micelle concentration, its effect on the aggregation of amantadine was enhanced onto boron nitride nanotube compared to just pure sodium dodecyl sulfate or amantadine on boron nitride nanotube. Our simulations show a remarkable restructuring and enhanced orientation of the water molecules around sodium dodecyl sulfate and amantadine adsorbed on boron nitride nanotube. METHOD: All molecular dynamics simulations were done using NAMD-2.9 package with CHARMM-36 force field. The nanotube PDB file was made by VMD with (12, 12) indexes. The nanotube atoms were considered to be fixed and periodic during the simulation process, and the ends did not cap with hydrogens. The initial PDB file of components was saved from ChemOffice software, and the webservers to obtain the charge and topology files were Reddb and Swiss Param webservers. The VMD software was used for structural visualizations and graphical analysis.

4.
J Mol Graph Model ; 85: 84-90, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30125780

RESUMO

In this study, the structural and redox properties of a novel ferrocene derivative in dichlomethane solvent were investigated. For this aim, various exchange-correlation functionals and basis sets in gas phase with different continuum solvation models and cavities in liquid phase were applied. The results indicated that UM06/6-31++G(d,p)/SDD level of theory successfully calculated bond lengths and angles with MADs = 0.02 Šand 0.78 deg., respectively. Also, its combination with CPCM-Pauling-UHF/6-31+G(d)/SDD level of theory in liquid phase effectively computed the redox potential with 0.06 V deviation from the experimental value. Moreover, transferability of the proposed method was studied through ferrocene molecule and its new synthesized derivative.


Assuntos
Eletroquímica , Compostos Ferrosos/química , Metalocenos/química , Modelos Moleculares , Compostos Ferrosos/metabolismo , Metalocenos/metabolismo , Conformação Molecular , Oxirredução , Transição de Fase , Solventes/química , Termodinâmica
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