Articles written in Bulletin of Materials Science

    • Electrical and magnetic properties of polyvinyl alcohol–cobalt ferrite nanocomposite films


      More Details Abstract Fulltext PDF

      Polyvinyl alcohol (PVA)–cobalt ferrite (CFO) nanocomposite films were synthesized by wet chemical method. The synthesized CFO nanomaterial was characterized by X-ray diffraction (XRD) and transmission electron microscopy(TEM), which confirm the formation of pure phase nanoparticles with cuboid shape. The variation in AC conductivity is measured as a function of frequency (within the range of 100 Hz$^{–1} MHz) and temperature (from 303 to 403 K). It was observed that the frequency exponent, $S$, decreases with increasing temperature, which is explained by correlated barrier hopping (CBH) conduction mechanism. Frequency dependence of real and imaginary parts of the dielectric permittivity of PVA–CFO nanocomposite films for different temperatures is studied on the basis of the modified Cole–Cole model. The dielectric permittivity of the samples reveals an increasing tendency with the concentration of CFO filler in PVA matrix. A high value of 89 emu g$^{−1}$ saturation magnetization and 652 Oe coercivity are observed in CFO nanoparticle.The coercivity increased in PVA–CFO nanocomposite when compared to CFO nanoparticle, which is expected due to inverse magnetostrictive effect. The increasing tendency of dielectric constant and magnetization of the nanocomposites with the increasing CFO concentration enhances the potential of applications in miniaturization of the antenna system and electromagnetic shielding materials.

    • Synthesis and evaluation of antibacterial properties of magnesium oxide nanoparticles


      More Details Abstract Fulltext PDF

      In this paper we studied the efficiency of magnesium oxide (MgO) nanoparticles with an average size of 27 nm synthesized by a simple soft chemical method, in killing both Gram negative and Gram positive pathogenic bacteria. The antibacterial activity was determined by a minimum inhibitory concentration technique, agar cup method and live count technique. These nanoparticles show the maximum antibacterial activity towards Bacillus sp. in comparison with Escherichia coli. Transmission electron microscopy analyses of the treated-bacterial strains showed a morphological deformation with increased cell wall disruption. From the analysis of the antibacterial activity of MgO nanoparticles it is revealed that6 $\mu$g ml$^{−1}$ of dose is sufficient for killing Bacillus sp. whereas it is 7.5 $\mu$g ml$^{−1}$ for E. coli. These doses may be used in medical application. MgO nanoparticles could be used as antibacterial agents after completion of successful in vivo trials.

  • Bulletin of Materials Science | News

    • Dr Shanti Swarup Bhatnagar for Science and Technology

      Posted on October 12, 2020

      Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
      Chemical Sciences 2020

      Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
      Physical Sciences 2020

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.