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Fullerene C70 thins films of thickness ~150 nm are prepared on quartz and glass substrates with thermal deposition technique. The films are irradiated with different ions (Au, Ag, Ni, Si) having different energies in order to vary the electronic energy loss (Se). The samples are also irradiated with range of fluence i.e. 1×1012 ions/cm² to 3×1013 ions/cm² for each energetic ion beam. The damage cross sections due to ion beam irradiation with different energetic ions (120 MeV Ag, 120 MeV Au, 90 MeV Ni, 55 MeV Si and 55 MeV Ni) are determined with Raman spectroscopy. A curve is plotted between electronic energy loss (Se) and damage cross section (σ) that is helpful to determine the damage cross section in fullerene C70 for any electronic energy loss. In addition, radius (r) of ion track can be approximated for any Se value from the constructed curve between r and Se. [ABSTRACT FROM AUTHOR]

Fabrication of a 2 × 4 multiple sensor array based on SnO2 thin films was demonstrated. SnO2 thin films were deposited on Al2O3 substrates and modified selectively using Au and CuO by sputtering. The sensor array was tested for its gas sensing characteristics towards H2S. The maximum sensor response (S=52) was observed in case of Au modified SnO2 thin films. By the surface modification using Au there is increase in the sensor response at all temperature. With the increase in temperature, sensor response decreases. [ABSTRACT FROM AUTHOR]

A 2 × 3 sensor array based on pure, Au and CuO modified (two of each kind) WO3 films was fabricated for e-nose application. Effect of surface modification has been investigated and correlated with the observed sensor response values. The sensor array was able to detect H2S,NH3 and NO selectively based on the sensor response pattern exhibited by the sensor array. WO3 sensor film modified with CuO exhibited a maximum sensitivity towards H2S (S = 92, 10 ppm, 250°C) while pure WO3 films exhibited better sensing characteristics towards NO (S=2.3, 10 ppm, 300°C) and NH3 (S=4.5, 50 ppm, 300°C). The shape of the curve remains unaltered by the change in the concentration of the gas. The shape and position of the combined response curve could be used to determine an unknown gas both qualitatively and quantitatively. [ABSTRACT FROM AUTHOR]