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Composites of polyethylene oxide and carbon nanotubes were produced by first deagglomerating highly agglomerated multi-walled carbon nanotubes in water, using a high-intensity ultrasonic probe, and then mixing with a solution of the polymer using a high-speed mixer. The deagglomeration of the nanotubes was carried out at different amplitudes of the vibrating ultrasonic probe. Differential scanning calorimetry results show an increase in melting temperature with increase in amplitude of sonication. Also, tensile test results show improved mechanical properties, with increased degree of deagglomeration of the nanotubes. SEM images show that the extent of nanotubes dispersion in the polymer matrix correlates with the extent of deagglomeration.

Polymer based composites have received high interest due to their unusual combination of stiffness and toughness that are difficult to attain from individual components. For this reason, they have been widely used in areas of transportation, construction, electronics and consumer products. Nanocomposites exhibiting a change in composition and structure over a nanometer length scale have been shown over the last few years to afford remarkable property enhancements relative to conventional composites. Organically modified clays can be effective reinforcing agents in manufactured polymer–clay nanocomposites. Polyacrylonitrile (PAN)/clay nanocomposites were prepared by the emulsifier free emulsion polymerization with variable power and frequency of ultrasound. The ultrasound waves of powers of 80 watt and 120 watt at frequencies of 60 KHz and 80 KHz were applied to assist the dispersion of organically modified clay with polymer matrix. The structure and morphology of nanocomposites were studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The oxygen permeability of the samples was measured by gas permeameter. A substantial reduction in oxygen permeability was observed by increasing clay loading and through sonication.

The application of count techniques in thermophilic-dry anaerobic reactor of Organic Fraction of Municipal Solid Waste (OFMSW) requires an adequate pre-treatment due to high content in solids present in the effluent. Therefore, an experiment was designed to select the best conditions of pre-treatment. Four conditions were assayed: without pre-treatment, shaking (60 seconds), addition of tensioactive agent (20µL of Tween 80 with a concentration [5µg/µL]) and sonication (5 seconds). The technique of quantification used to determine the best pre-treatment was the DAPI epifluorescence microscopy method. All quantitative data were checked for normality before Paired-Samples T Test and an analysis of variance (ANOVA) with Spss v11.5 program. It can be concluded that the most appropriate pre-treatment applied for microbiological count of high solids content samples was the addition of Tween 80 and 120 seconds of shaking.

Sonication is powerful agitation. Deposited films and electrochemical kinetics parameters were affected. The effects of micro-jet on the deposition rate and shock wave pressure on the smooth of deposited film had been studied. The bath was 0.095 mol/dm³NiSO₄6H₂O, 0.005 mol/dm³Na₂MoO₄, 0.3 mol/dm³NaH₂PO₂, 0.06 mol/dm³Na₃C₆H₅O₇2H₂O, and pH 8.5. The temperature was 353 ± 3 K. The plating rate in sonication had a little faster compared with that in stationary state with micro-jet effects. The thickness of plated film was affected with bath temperature and bath composite. When the concentration ratio of Ni and Mo increased and ratio of Mo was decreased, thickness was thicker. The plated film was an amorphous. Plating rate was faster with micro-jet. The surface was smoothed with shock wave pressures.