A series of biodegradable polymeric nanocomposite films based on poly(lactic acid) (PLA) and magnesium-aluminum layered double hydroxide (Mg-Al LDH) nano-particles was prepared by solution casting method. Two different Mg-Al LDH nano-fillers at Mg:Al mol ratios of 2:1 and 3:1 were synthesized by co-precipitation technique and to improve the interfacial interaction, the nanoparticles were modified by intercalating sodium dodecyl sulfate (SDS) surfactant into the LDH galleries. The PLA nanocomposite films, prepared using unmodified (Mg-Al LDH) and modified (SDS-Mg-Al LDH) nano fillers. Both XRD and TEM analyses showed an increasing dispersion and improved exfoliation of SDS-Mg-Al LDH into the PLA matrix. DMA analysis indicated that, at each composition, filler modification resulted in higher storage modulus and T g . The composite films showed increasing oxygen barrier property up to 23.5 %, compared to PLA. The films containing 5 % of SDSMg-Al LDH at Mg:Al ratio of 3:1 exhibited significant increase in oxygen barrier property.

The aim of the present study was to evaluate responses of potential indicator bacteria (i.e. Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis) to the ultraviolet (UV) radiation and the UV/hydrogen peroxide (H 2 O 2 ) disinfection processes of surface waters with different qualities in terms of humic content. The UV and the UV/H 2 O 2 processes were applied to waters containing various concentrations

Polylactic acid/layered silicate nanocomposite films were prepared by solution casting technique. Four types of organo modified montmorillonite and an unmodified bentonite were used as inorganic fillers. The structural characterizations were done by FTIR/ATR and dispersion of the layered silicates was deter mined by XRD. XRD results showed that the prepared nanocomposites showed flocculated, intercalated and exfoliated structure. The highest crystallinity degree obtained was 28. Overall migration tests were studied with food simulants included distilled water, 3% acetic acid, 95% ethanol. The migration values of all the pre pared films were found to be below the allowed limit (10 mg/dm 2 ). The best result in oxygen gas transmission and water vapor transmission rates were 233.4 cm 3 mm/m 2 day MPa and 98.3 g/m 2 day, respectively. Conse quently the oxygen barrier property has increased by 34% and water vapor barrier property increment was 65% when compared to pure PLA film.

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The aim of the present study was to evaluate and compare the effectiveness of two solar-based processes (solar/H 2 O 2 and solar photo-fenton) for the inactivation of E. coli in simulated domestic wastewater. Different H 2 O 2 concentrations were applied for solar/ H 2 O 2 process (5, 10, 50 and 150 mg/L) and for solar photo-fenton process (10, 30 and 50 mg/L) at different light intensities (200 W/m 2 and 500 W/m 2 ) in glass beakers under solar simulator. The application of light at 200 W/m 2 and 500 W/m 2 showed no difference on the removal time in the absence of hydrogen peroxide. However, in the presence of H 2 O 2 , removal times decreased significantly with the elevation of light intensity. When H 2 O 2 concentration was increased, the removal times decreased consistently for solar photofenton process and solar/H 2 O 2 process both at 200 W/m 2 and 500 W/m 2 , except for the process with solar/50 mg/L H 2 O 2 at 500 W/ m 2 . These results imply that solar/H 2 O 2 and solar photo-fenton processes may be a good alternative for disinfection of domestic wastewaters which contains high amounts of organic and inorganic materials.