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a b s t r a c t Nanostructured TiO 2 thin films were deposited on AISI 304 austenitic stainless steel by sol-gel process, dip coating technique. Influence of the number of layers, addition of polyethylene glycol (PEG) in initial sol, morphology and the surface roughness parameters of titania films on corrosion resistance of coated stainless steel were examined. Prepared films were characterized by SEM-EDS and AFM analysis. Electrochemical corrosion behavior of the coated stainless steel substrates was evaluated in simulated marine environment in 3 wt.% aqueous NaCl solution by electrochemical impedance spectroscopy (EIS) and in 0.5 M aqueous HCl solution by potentiodynamic polarization.

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The structure-property relationship in alginate microparticles (microspheres and microcapsules prepared with or without Trichoderma viride spores (Tv) was investigated. Surface morphology, structure and release behavior from alginate microparticles strongly depend on calcium concentration and presence of Tv and chitosan layer. All microparticles exhibited a granular surface structure with substructures consisting of abundant smaller particles. In vitro active agents release study revealed that the increase in calcium cation concentration reduced the release rate of Tv (˜84% for microspheres;˜57% for microcapsules) and calcium cations (˜20% for microspheres;˜23% for microcapsules). The average decrease in k values due to chitosan layer addition is 41% for Tv and 93% for calcium ions, respectively. The underlying Tv release mechanism from microspheres is anomalous transport kinetics, whereas from microcapsules is controlled by Type II transport. The differences in microparticle surface properties did not affect the mechanism controlling calcium ions release detected as diffusion through microparticles.