Browsing by Author "Parida, L."

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    Antibacterial studies of vitamin E encapsulated lemongrass oil nanoemulsions against gram-negative and gram-positive bacteria
    (John Wiley and Sons Inc, 2025) Prakash, V.; Nair, V.; Parida, L.
    The current study assessed the antibacterial properties of vitamin E nanoemulsions, synthesized using a low-energy phase inversion emulsification method. The nanoemulsions were characterized through particle size analysis, and their antimicrobial efficacy was assessed against the bacteria Staphylococcus aureus and Escherichia coli by disc diffusion method. The mechanisms underlying the antibacterial activity were investigated through scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The vitamin E nanoemulsions demonstrated significant antibacterial activity against both bacterial strains. Specifically, the zone inhibition diameters for S. aureus and E. coli increased by 5.68 times and 2.61 times, respectively, compared to the pure vitamin E component. The incorporation of Tween 80 as a surfactant resulted in a reduction of the antibacterial properties of the nanoemulsions. Furthermore, the study found that the vitamin E encapsulated lemongrass oil nanoemulsion demonstrated higher antibacterial activity to S. aureus and E. coli when compared to other nanoemulsions. The nanoemulsions exhibited significantly greater resistance to S. Aureus as compared to E. coli. SEM and FTIR analyses revealed that the nanoemulsions induced alterations in bacterial cell membrane permeability and surface characteristics. These results confirmed the mechanism of vitamin E nanoemulsions antibacterial activity and established a crucial base for their potential use in food matrices. © 2025 Canadian Society for Chemical Engineering.
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    Experimental analysis, modelling, and optimisation of alkaline leaching in coal fly ash treatment
    (Taylor and Francis Ltd., 2025) Murmu, A.K.; Sankar Rao, C.S.; Parida, L.; Senapati, P.K.
    The present study introduces a novel integration of Gaussian Process Regression (GPR) modelling and Particle Swarm Optimisation (PSO) to improve the efficiency of alkaline leaching of coal fly ash (CFA). The selected operating variables for the alkali leaching process include temperature, leaching time, concentration of the alkalis (NaOH and KOH), and the liquid-to-solid ratio. A GPR model was employed for data fitting of the leaching process, yielding high predictive accuracy with R2 values of 0.9978 for SiO2 dissolution, 0.9742 for Al2O3 dissolution, and 0.9945 for Al/Si ratio in the NaOH-treated CFA process. In the KOH-treated CFA process, the GPR model achieved R2 values of 0.9645 for SiO2 dissolution, 0.9873 for Al2O3 dissolution, and 0.9960 for Al/Si ratio. Under optimised conditions, both NaOH- and KOH-treated leaching processes demonstrated an effective desilication of CFA, with NaOH showing higher silica dissolution and KOH yielding greater alumina recovery. The resulting Al/Si ratios further confirmed the efficiency of treatment, with the higher ratio in the NaOH process reflecting more effective silica removal. These findings demonstrate the efficacy of using PSO in conjunction with GPR models to optimise leaching processes, offering a significant advancement in the efficient processing of CFA through precise control of operational parameters. © 2025 Canadian Institute of Mining, Metallurgy and Petroleum.