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In this paper Multi-walled carbon nanotubes are synthesized by arc-discharge and chemical vapor decomposition methods. Multi-walled carbon nanotubes are synthesized on thin film of nickel sputtered on silicon substrate by thermal chemical vapor deposition of acetylene at a temperature of 750°C. The flow of current in arc-discharge method varies in the range 50-200 Amps. Further arc-synthesized carbon nanotubes are characterized by X-Ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and the results are compared with nanotubes grown by chemical vapor deposition method. XRD result shows a characteristic peak (002) at 26.54° corresponding to presence of carbon nanotubes. SEM and TEM results give morphology of as-synthesized multiwalled nanotubes. TEM results indicate synthesis of well graphitized carbon nanotubes by arc-discharge method. Dispersion of arc synthesized nanotubes in SDS solution under the effect of different sonication time is studied. Dispersion of nanotubes in SDS solution is analyzed by using UV-vis-NIRspectroscopy and it shows an absorption peak at 260 nm. It was found that with the increase in sonication time, the absorption peak in UV-vis-NIR spectra will increase and optimum sonication time was 2 hour. Functionalization of synthesized carbon nanotubes by H 2 SO 4 and HNO 3 acids has been studied and analysis of functionalized groups has been done by using FT-IR spectroscopy and compared and the results are reported in this paper. FT-IR spectroscopy verifies the presence of carboxylic groups attached to carbon nanotubes. These functional groups may change properties of carbon nanotubes and may be used in vast applications of carbon nanotubes.Index Terms-Electron microscopy, FT-IR spectrsocopy, multi-walled carbon nanotube, X-ray diffraction.

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Cloud computing is a leading edge computing paradigm in which massively

In the present study we explored metal enhanced bioluminescence in luciferase enzymes for the first time. For this purpose a simple and reproducible one pot synthesis of gold-silver alloy nanoparticles was developed. By changing the molar ratio of tri-sodium citrate and silver nitrate we could synthesize spherical Au-Ag colloids of sizes ranging from 10 to 50 nm with a wide range of localized surface plasmon resonance (LSPR) peaks (450-550 nm). The optical tunability of the Au-Ag colloids enabled their effective use in enhancement of bioluminescence in a luminescent bacterium Photobacterium leiognathi and in luciferase enzyme systems from fireflies and bacteria. Enhancement of bioluminescence was 250% for bacterial cells, 95% for bacterial luciferase and 52% for firefly luciferase enzyme. The enhancement may be a result of energy transfer or plasmon induced enhancement. Such an increase can lead to higher sensitivity in detection of bioluminescent signals with potential applications in bio-analysis.