Cathodic cage discharge was developed recently in order to eliminate phenomena as edge effect and overheating, which occurs during conventional processes. In this study, the effect of cage configuration in active species during the deposition process and optical properties of TiN film were studied. TiN compound was chosen because its optical properties are very sensitive to slight variations in microstructure and film thickness, becoming a good monitoring tool in fabrication process control. Cages were made of titanium and have different holes numbers and holes diameter. Electrical efficiency of the system and optical properties of TiN films were strongly influenced by experimental conditions. It was found that with more holes at the top of cage, deposition rate and crystallinity were higher, if compared to cages with a small number of holes at the top. On the other hand, the opposite behavior was observed when more holes were located at the sidewall of cage.

The use of polymeric medical devices has stimulated the development of new sterilization methods. The traditional techniques rely on ethylene oxide, but there are many questions concerning the carcinogenic properties of the ethylene oxide residues adsorbed on the materials after processing. Another common technique is the gamma irradiation process, but it is costly, its safe operation requires an isolated site, and it also affects the bulk properties of the polymers. The use of gas plasma is an elegant alternative sterilization technique. The plasma promotes efficient inactivation of the microorganisms, minimizes damage to the materials, and presents very little danger for personnel and the environment. In this study we used plasma for microbial inhibition of chitosan membranes. The membranes were treated with oxygen, methane, or argon plasma for different time periods (15, 30, 45, or 60 min). For inhibition of microbial growth with oxygen plasma, the time needed was 60 min. For the methane plasma, samples were successfully treated after 30, 45, and 60 min. For argon plasma, all treatment periods were effective.

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The treatment of effluents requires new methodologies for the treatment of the tailings. One option is the use of natural coagulants. Chitosan has amino groups in the polymeric chains that allow it to act as a cationic polyelectrolyte and present a high density of charges, which are easily adsorbed on negatively charged surfaces, which is the case for most colloidal impurities present in water. Thus, this work used chitosan in the coagulation/flocculation process to remove color, turbidity and suspension of solids, as a strategy in the treatment of effluents. For that, samples of effluents from the textile industry in the of State of Rio Grande do Norte and samples of effluents from stabilization Lagoons in the municipalities of Touros and Santa Cruz were used in the coagulation/flocculation tests using jar-test. The results proved to be efficient for the removal of color, turbidity and suspension of solids from the samples. The best dosages were 22.5 mg/L and 37.5 mg/L for textile industry effluents, 52.5 mg/L and 60 mg/L for Santa Cruz lagoon effluent; 30 mg/L and 37.5 mg/L for effluent from Touros lagoon. It was observed in this work that chitosan presented in an optimal proportion, that is, the addition of more chitosan did not provide greater removal and that it can be used as a coagulant/flocculant in the treatment of effluents from both the textile industry and domestic effluents, replacing the synthetic coagulants or being used together with them.

The skin is the organ that protects the internal organism against pathogenic agents from the external environment. Therefore, rapid wound healing becomes an important target against exposure of the organism to pathogens. Thus, the use of biopolymers as dressings has been gaining prominence, among them, chitosan. Chitosan is a biomaterial that has high biological compatibility, biodegradability, low toxicity and healing effect. The objective of this research was to produce a chitosan-based biomaterial, incorporated with a hydroalcoholic extract from the bark of Anacardium microcarpum Ducke. The membranes were characterized in terms of color, homogeneity, flexibility, thickness, wettability and degree of swelling. The membranes were transparent, homogeneous and flexible with an average thickness of 5 micrometers. In swelling, there was absorption of 50%, mass loss below 6% and durability greater than 21 days. As for wettability, the membranes were moderately hydrophilic. The membranes showed promising chemical and physical characteristics to be a curative biomaterial.