A Protected And Lightweight Data Distribution Program For Mobile Cloud Computing

Because of the widespread adoption of cloud computing, mobile devices may now store and access personal data from any location at any time. As a result, the data security issue in mobile cloud is becoming increasingly serious, impeding the growth of mobile cloud. There have been several researches undertaken in order to enhance cloud security. However, because mobile devices have limited processing capabilities and power, the majority of them are not suitable for mobile cloud. Mobile cloud applications require solutions with a low computational overhead. We propose a lightweight data sharing mechanism for mobile cloud computing in this work. It provides attribute description fields to achieve lazy-revocation, which is a difficult problem in CP-ABE systems based on programs. The experimental findings suggest that when users share data in mobile cloud settings, a lightweight data sharing technique may effectively minimize the overhead on the mobile device side

Enhancement of photocatalytic degradation of an organic pollutant by WO3 nanopowders: carbon doping

The photocatalytic activity of C doped WO3 is monitored by studying the degradation of the methylene blue (MB) aqueous dye solution under visible light irradiation. The photocatalyst WO3 was synthesized by the solvothermal method and modified by doping carbon into it in the molar ratio 1:1, 1:2, 1:3 and 1:4 under hydrothermal process. The photocatalysts were characterized for structural and optical properties. XRD was taken to identify the phase and structure, also confirms the successful incorporation of carbon into WO3 lattice site. Morphology and elemental composition were analyzed using SEM and EDAX. The UV-DRS spectrum showed an increase in absorption intensity with increasing carbon content with decreases in bandgap from 3.0 eV to 2.6 eV. PL emission spectra gave blue emission (484 nm) and green emission (555 nm). Finally, the photocatalytic response graph of C doped WO3 with time showed an excellent absorption property and an enhanced visible-light photocatalytic activity compared to pristine WO3

Synthesis, characterization, luminescence and photocatalytic studies of layered perovskites NaMMgWO6 (M = La, Pr, Sm)

The synthesis, characterization, optical and photocatalytic studies of AA'BB'X6 type perovskites, NaMMgWO6 (M = La, Pr, Sm), which have an ordering of both the cation sub-lattices, is reported.  The obtained NaMMgWO6 materials have been prepared using ethylene glycol assisted gel-burning method and characterized by X-ray diffraction patterns, UV-vis diffused reflectance spectra, scanning electron microscopy, Fourier transformation infrared spectra, energy dispersive spectra and fluorescence spectra. The photocatalytic dye degradation performance of the as-synthesized perovskites has been evaluated with methylene blue and methyl violet as model water pollutants using radical quenchers

Enhancement of photocatalytic degradation of an organic pollutant by WO3 nanopowders: Carbon doping

763-771The photocatalytic activity of WO3 and C doped WO3 has been monitored by studying the degradation of the methylene blue (MB) aqueous dye solution under visible light irradiation. The photocatalyst WO3 has been synthesized by the solvothermal method and modified by doping carbon into it in the molar ratio 1:1, 1:2, 1:3 and 1:4 under hydrothermal process. The photocatalysts have been characterized for structural and optical properties. XRD has been taken to identify the phase and structure, also confirms the successful incorporation of carbon into WO3 lattice site. Morphology and elemental composition were analyzed using SEM and EDAX. The UV-DRS spectrum showed an increase in absorption intensity with increasing carbon content with decreases in band gap from 3.0 eV to 2.6 eV. PL emission spectra gave blue emission (484 nm) and green emission (555 nm). Finally, the photocatalytic response graph of C doped WO3 with time showed an excellent absorption property and an enhanced visible-light photocatalytic activity compared to pristine WO3

Synthesis, characterization, luminescence and photocatalytic studies of layered perovskites NaMMgWO₆ (M = La, Pr, Sm)

435-443The synthesis, characterization, optical and photocatalytic studies of AA'BB'X6 type perovskites, NaMMgWO6 (M = La, Pr, Sm), which have an ordering of both the cation sub-lattices, is reported.  The obtained NaMMgWO6 materials have been prepared using ethylene glycol assisted gel-burning method and characterized by X-ray diffraction patterns, UV-vis diffused reflectance spectra, scanning electron microscopy, Fourier transformation infrared spectra, energy dispersive spectra and fluorescence spectra. The photocatalytic dye degradation performance of the as-synthesized perovskites has been evaluated with methylene blue and methyl violet as model water pollutants using radical quenchers

Synthesis, characterization and photocatalytic activity studies of tellurium containing defect pyrochlores, MSn_0.5Te_1.5O₆ (M = K, Ag, Cu_0.5 and Sn_0.5)

1174-1181Four new metal tin tellurites, MSn0.5Te1.5O6 (M = K, Ag, Cu0.5 and Sn0.5), have been synthesized by standard solid-state and facile ion exchange reactions and characterized by powder X-ray diffraction, FTIR, SEM-EDS and UV-vis diffuse reflectance spectroscopic techniques. All the compositions crystallize in cubic lattice with Fdmspace group, and are isomorphous with KTi0.5Te1.5O6. The photocatalytic activity of the as prepared materials for methylene blue and methyl violet degradation has been investigated under visible light irradiation. The AgSn0.5Te1.5O6 photocatalyst exhibits higher photocatalytic activity than MSn0.5Te1.5O6 (M = K, Cu0.5 and Sn0.5) for photodegradation of methylene blue and methyl violet. The higher photocatalytic performance of AgSn0.5Te1.5O6 is ascribed to its low band gap energy, which endows it with a very strong photooxidation ability to produce OH● and O2●- radicals as active species. The catalyst stability and mechanism of photocatalysis is also discussed