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The influence of N plasma on the antibacterial properties of polystyrene/fullerene (C/PS) nanocomposite films with two concentrations is investigated. A comparison is made between the surface characteristics of the films before and after plasma irradiation for different time intervals. The alterations induced on the surface of the films after treatment are analyzed by contact angle and surface energy measurements, FTIR spectroscopy, and atomic force microscopy. The antibacterial properties, growth, biofilm formation, and adhesion of the nanocomposite films against two multidrug-resistant bacterial strains, Staphylococcus aureus KT337489 and Pseudomonas aeruginosa KT337488, are investigated before and after plasma irradiation. The results indicate that P. aeruginosa is more sensitive to treatment than S. aureus as well as an enhancement of the anti-adhesion of both strains to treated surfaces through exposure.

The spectroscopic properties of 1,4,170 and 750 oxazine dyes doped in polymethyl methacrylate (PMMA) were measured and studied. The photostability of these samples were outdoor tested during the four seasons. The optical efficiency of luminescent solar concentrator (LSC) of 750 oxazine dye was measured and calculated hourly for one year (1995)(1996) considering day 21 as a reference day for each month. The performance of LSC has been tested at three different positions using, X-Y tracker.

The aim of this study is to analyze the relation between the reaction rate coefficients, hence the production of active species, and the gas mixing ratio in a comparative way between Ar/N 2 and He/N 2 gaseous mixtures. The Ar and He contributions ranged from 0 to 100 % at a total gas pressure of 0.4 Torr and a reduced electric field E/N of 610 Td. Langmuir probe is employed to measure electron temperature. The results showed that adding Ar to N 2 plasma reduced both the discharge operating voltage and the electron temperature. However, an opposite action is obtained on Adding He. Also, Ar can induce the dissociation of molecular nitrogen and increase the production of nitrogen atoms, however it has an insignificant effect on the nitrogen ionization mechanism. On the other hand, He addition enhances the production of , N + and N-atoms through ionization, ionization dissociation and dissociative reaction, however it has a decreasing effect on the dissociative recombination mechanism