Papers by Author: J. Kumar

Abstract: Hydroxyapatite is a bioceramic which has a wide range of medical application for bone diseases. To enhance its usage, we have prepared ciprofloxacin loaded nanohydroxyapatite (HA) composite with a natural polymer, alginate, using wet chemical method at low temperature. The prepared composites were analyzed by various physicochemical methods. The results show that the nanoHA crystallites are well intact with the alginate macromolecules. For the composite system FT-IR study is done. The drug is pre-adsorbed onto the ceramic particle before the formation of composite. The thermal behavior of composite has been studied using thermo gravimetric analysis (TGA). This paper communicated the Influence of Polymer concentration on the Controlled drug release from hydroxyapatite Nanocomposites

Abstract: We report on the growth mechanism, structural and optical characterstics of Gallium nitride nanowires prepared on sapphire substrates (0001) by reacting metal gallium with Gallium nitride powder and ammonia in the temperature range of 800 to 1050°C. GaN nanowires samples were characterized by using X-ray diffraction technique which shows wurtzite structure of GaN nanowires and the lattice parameters are calculated. Scanning electron microscopy images reveals that the dimension of the nanowires are around 60 – 80 nm and the length of 1 - 2 millimeters. Three Raman modes of GaN have been observed at frequencies 530, 554 and 564 cm-1. Photoluminescence spectrum reveals the band edge at 3.4 eV and gives yellow luminescence.