Browsing by Author "Altaf, Mohammad"

Now showing 1 - 3 of 3
  • Thumbnail Image
    PublicationOpen Access
    Characterization of Triangular Gold Nanoparticles Using Aloe arborescens Leaf Extract: A Green Synthesis Approach
    (Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry, 2016-04-14) Altaf, Mohammad; Jaganyi, Deogratius
    Herein, the authors show the use of the Aloe arborescens leaf extract for green synthesis of gold nanoparticles in water at room temperature under very mild conditions. The synthesis of the gold nanoparticles was complete in several minutes, and no extra stabilizing or capping agents were necessary. The size of the nanoparticles could be controlled by varying the concentration of the leaf extract. The silver nanoparticles and reaction process were characterized by UV-vis spectrometer, Fourier transform infrared spectroscopy, and transmission electron microscopy. The UV-visible spectra of synthesized nanoparticles showed absorption maxima at 540 nm. Transmission electron microscopy images confirm that the nanoparticles are spherical and triangular in shape.
  • Thumbnail Image
    PublicationOpen Access
    Characterization of Triangular Gold Nanoparticles Using Aloe arborescens Leaf Extract: A Green Synthesis Approach
    (Journal of coordination chemistry, 2016-04-14) Jaganyi, Deogratius; Altaf, Mohammad
    Herein, the authors show the use of the Aloe arborescens leaf extract for green synthesis of gold nanoparticles in water at room temperature under very mild conditions. The synthesis of the gold nanoparticles was complete in several minutes, and no extra stabilizing or capping agents were necessary. The size of the nanoparticles could be controlled by varying the concentration of the leaf extract. The silver nanoparticles and reaction process were characterized by UV-vis spectrometer, Fourier transform infrared spectroscopy, and transmission electron microscopy. The UV-visible spectra of synthesized nanoparticles showed absorption maxima at 540 nm. Transmission electron microscopy images confirm that the nanoparticles are spherical and triangular in shape.
  • No Thumbnail Available
    PublicationMetadata only
    Oxidative degradation of l-histidine by manganese dioxide (MnO2) nano-colloid in HClO4 medium with/without using TX-100 catalyst: a kinetic approach
    (Royal society of Chemistry, 2016-10-24) Jaganyi, Deogratius; Altaf, Mohammad
    The kinetics of the oxidative degradation of L-histidine (His) in perchloric acid medium by freshly prepared manganese dioxide (MnO2) nano-colloid have been investigated with and without using TX-100 catalyst at a constant temperature of 35 °C. The progress of the oxidation reaction was checked by monitoring the decrease in absorbance of MnO2 spectrophotometrically at 360 nm. The reaction was observed to be first order with respect to [MnO2] and fractional with respect to [His] and [HClO4] in both uncatalysed and TX-100-catalysed paths. The catalytic effect of TX-100 on the oxidation reaction has been explained by the Tuncay model. Protonated L-histidine is bound to TX-100 and forms a [TX-100–His] intermediate complex which further reacts with MnO2 and decomposes into the oxidation products: 2-imidazole acetaldehyde, Mn(II), NH4+ and CO2. On the basis of the kinetics results, a possible reaction mechanism is proposed.