No abstract

A facile and ecofriendly method for synthesis of nano size iron oxide (Fe 2 O 3 ) decorated graphene (GINC) hybrid by the use of ultrasonication via microwave irradiation has been developed. During this process, nano size Fe 2 O 3 particles with a size of approximately 20-30 nm were decorated uniformly over graphene sheet. The nano hybrid was characterized by XRD, HRTEM and Raman spectroscopy 10 and mapping. To study the enhancement of catalytic activity of iron oxide by making GINC, several AP based compositions containing 1-5 weight % GINC were made and characterized through simultaneous thermal analysis (STA). Along with this, formulations with other catalyst with 1-5 weight % concentrations were also prepared and evaluated. Experimental results showed that GINC with 5 weight % concentration was much more effective as compared to other compositions. To extend this application further as a burn rate enhancer in composite propellant, several formulations of composite propellant containing 1 part of different burn rate enhancers like Fe 2 O 3, nano 15 size Fe 2 O 3 and GINC were made and evaluated by means of theoretical prediction, viscosity, ballistic properties, sensitivity parameter and thermophysical properties. To quantify the burn rate enhancement in the presence of GINC, burn rate measurement, STA, DSC and activation energy calculation were performed. The results show that burn rate of propellant increases from micron size Fe 2 O 3 (30% increases) to nano Fe 2 O 3 (37% increase). In the presence of GINC, a significant increase (52%) in burn rate is achieved. In GINC, effective iron content is about 50% as compared to nano and micron size Fe 2 O 3 . Hence GINC was found to be excellent burn rate 20 modifier for advance AP based propellant system. 65 and environmentally benign techniques.The metal/metal oxide particles have got much attention due to their distinctive optical, electronic and catalytic

Hydroxyapatite has been widely used for a variety of bone filling and augmentation applications. But the poorly resolved X-ray image of certain hydroxyapatite (HA) based implants such as porous blocks and self setting HA cements is a radiological problem to surgeons for monitoring of the implant and early diagnosis complications. In the present work the practical difficulty related to the reduced X-ray opacity was overcome by exploiting the contrast enhancement property of iron oxide nano particles. Sintered nano iron oxide-HA composite ceramics were prepared from powders produced through a co-precipitation route. The phase purity and bioactivity of the composites were analyzed as a function of percentage iron oxide in the composite. The X-ray attenuation of dense and porous composites was compared with pure HA using a C-arm X-ray imaging system and micro computed tomography. In all the prepared composites, HA retains its phase identity and high X-ray opacity as obtained for a composition containing 40 wt% iron oxide. The increased cell viability and cell adhesion nature depicted by the prepared composite offers considerable interest for the material in bone tissue engineering applications.