Browsing by Author "Samir, A"

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    Characterization of borate glasses doped with copper oxide for optical application
    (SPRINGER, 2019-04) Samir, A; Hassan, Moukhtar A; Abokhadra, A; Soliman, L. I; Elokr, M
    Borate glasses having the formula x CuO-(50-x)B2O3-30Na(2)O-20ZnO where x=0, 0.2, 0.5, 1, 4 and 7mol% were investigated. The samples were prepared using the conventional melt-quenching technique. Physical properties were studied such as; X-ray diffraction, FTIR spectra, and UV-visible transmission. The optical basicity, average electro negativity have been estimated. The estimated optical basicity, unlike electron negativity, exhibits an increase with increasing the CuO content. FTIR spectra show that BO4 ratio decreases with increasing CuO content leading to the formation of non-bridging oxygen's. Some optical parameters such as the optical band gap, band tail width, crystal field strength and the UV and NIR cut off were determined. The transmission spectrum revealed that the glassy samples containing high content of copper oxide behave as bandpass filters at higher content. The characterized parameters of these filters were found to be highly affected by the addition of CuO. In these glasses the broad absorption band observed at the wavelength 550nm is characterized by the existence of Cu2+ ions. The optical absorption and ESR studies suggest that, the Cu-ions exist in the Cu2+ state and act as modifiers by increasing the degree of disorder in the glass network. Hence, the present system behaves as a bandpass filter in the ultraviolet-visible region.
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    The synergistic effect of biosynthesized silver nanoparticles from a combined extract of parsley, corn silk, and gum arabic: In vivo antioxidant, anti-inflammatory and antimicrobial activities
    (nstitute of Physics Publishing, 2020) Helmy, A; El-Shazly, M; Seleem, A; Abdelmohsen, U; Salem, M.A; Samir, A; Rabeh, M; Elshamy, A; Singab, A.N.B
    View references (62) Microbial resistance, oxidative stress, and inflammatory conditions are among the leading causes of death worldwide. In the current work, silver nanoparticles (AgNPs) were biosynthesized using the aqueous extracts of parsley, corn silk (CS), gum Arabic (GA) or combination of the three extracts. The formed nanoparticles were characterized using three techniques including transmission electron microscopy (TEM), UV-visible spectrophotometer and Fourier-transform infrared spectroscopy (FTIR). The antioxidant, anti-inflammatory, and antimicrobial activities were tested for the formed nanoparticles, the aqueous extracts of each of the three plants and their combination. Oxidative stress was induced by alloxan which promoted the development of diabetes mellitus in rats. Inflammation was induced by injecting carrageenan in rats' paws. Pathogenic microorganisms causing serious urinary tract infection (UTI) were selected for the antimicrobial assay. All aqueous extracts and the biosynthesized AgNPs showed variable degrees of antioxidant, anti-inflammatory and antimicrobial activities, however, the AgNPs biosynthesized by the combination of the three aqueous extracts was the most effective one. LC/MS was done to identify the compounds present in the crude extracts that may be responsible for the observed biological activities. LC/MS resulted in the identification of 13 compounds. Docking experiments on COX-1 (cyclooxygenase-1) and COX-2 (cyclooxygenase-2) were performed to determine the compounds responsible for the anti-inflammatory activity of the extracts. The results showed that silver nanoparticles synthesized by the combination of the three aqueous extracts are considered promising candidates for the development of antioxidant, anti-inflammatory and antimicrobial agents