S K SAHU
Articles written in Bulletin of Materials Science
Volume 19 Issue 6 December 1996 pp 1125-1132 Papers Presented At The Materials Science Section Of The 82nd Indian Science Congress, Calcutta, 1995
Fast neutron activation analysis technique using 14 MeV neutrons has been applied to analyse nitrogen, chlorine and oxygen content of glycidyl azide polymers (GAP) with$$\bar M$$n around 2100. It has been found that the method is better suited for elemental analysis of GAP than infrared spectroscopy. In fact IR spectral analysis fails to detect chlorine in the polymer when the chlorine content is approximately less than 20%. Oxygen is directly measured by fast neutron activation analysis which is unique.
Volume 40 Issue 2 April 2017 pp 301-306
Microwave-absorbing materials based on reduced graphene oxide (r-GO)/ strontium titanate were prepared by embedding in epoxy matrix. R-GO and strontium titanate were synthesized and characterized before composite fabrication. Microstructures of the constituent elements were studied by scanning electron microscopy and X-ray diffraction (XRD). Microwave absorption capabilities of the composite absorbers were investigated using a Vector Network Analyser in the range 8–12 GHz. A maximum reflection loss of $−$7.5 and $−$16.4 dB was obtained at 9.3 and 12.08 GHz, respectively, for 2% (w/w) r-GO-loaded epoxy composites. A maximum attenuation of $−$12.8 dB at 9.3 GHz was obtained for the strontium titanate/epoxy composite. However, double-layer composite with r-GO/strontium titanate/epoxy composition showed the maximum reflection loss of $−$15.1 dB at 9.47 GHz and $−$9.65 dB at 12.3 GHz. All the results are discussed in terms of complex permeability and permittivity. The study revealed that intrinsic conductivity and polarization of the r-GO particles and dielectric polarization of the strontium titanate within epoxy matrix contribute to the microwave absorption.
Volume 42 | Issue 6
Click here for Editorial Note on CAP Mode