The inhibition efficiency (IE) of an aqueous extract of garlic in controlling corrosion of carbon steel in well water in the absence and presence ofZn2+has been evaluated by mass-loss method. The formulation consisting of 2 mL of garlic extract and 25 ppmZn2+offers 70% inhibition efficiency to carbon steel immersed in well water. Polarization study reveals that this formulation controls the anodic reaction predominantly. FTIR spectra reveal that the protective film consists ofFe2+-allicin complex and Zn(OH)2.

The presence of surface active carboxylic sites and the nature of the (ordered and defective) stacking of graphite layers in the nanotubes determined the vacuum sensing characteristics.

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In the present study, the ultrasound in pulsed mode was used as a part of an advanced oxidation method. The influence of the pulsed ultrasound mode for the preparation of the zinc oxide (ZnO) wurtzite nanoparticle was investigated. The catalysts synthesized were analysed using SEM, TEM, EDAX, BET surface area, XRD, and DRS to study their morphological and structural characterizations. The ZnO nanoparticles exhibited a highly hexagonal structure from pulsed sonication synthesis route. The efficiency of the decolourization of the reactive red 4 (RR4) dye was studied under different operation parameters such as dye concentration, initial solution pH, oxidant (e.g., H2O2) concentration, and catalyst loading. The hybrid combined process of pulsed sonolysis, pH (4.0), H2O2 (17.64 mmol), and catalyst (0.35 g/L) achieved 97% degradation and 87.5% chemical oxygen demand removal in about 20 min of reaction time. The cyclic degradation studies of RR4 removal with 0.35 g/L of ZnO showed the reusability of catalyst up to the fifth removal cycle with negligible loss in the catalytic performance. GC–MS study, used for the detection of the RR4 intermediates, revealed the oxidation–reduction reaction by the reactive radicals proceeded via the reductive cleavage of the azo bonds. The studied process, based on the pulsed ultrasound, is found to be effective for the degradation of RR4 dye.

SILAR method is adopted for the deposition of titanium dioxide (TiO2) thin films. Titanium trichloride and ammonium hydroxide are used as the cationic and anionic precursors respectively. Deposition parameters such as growth rate, individual dipping and rinsing times and precursor concentration are optimized to obtain uniform, adherent films. As-deposited TiO2films are annealed at 300°C and 400° C. The crystallization behaviour of TiO2thin films is analysed by X-ray diffraction. Optical constants of the films are evaluated using UV-Vis spectrophotometry. Effect of deposition parameters on the optical properties of the films is analysed.The direct and indirect band gap values of the TiO2thin films is in the range of 3.4-3.8 eV and 2.1-3.8 eV respectively.