Advances in Science and Technology Vol. 66

Abstract: TaN–Cu and TaN-Ag nanocomposite films were deposited by reactive co-sputtering on Si. The films were then annealed using RTA (Rapid Thermal Annealing) at 400 °C for 2, 4, 8, 15 minutes respectively to induce the nucleation and growth of metal particles in TaN matrix and on film surface. The samples were then tested for their anti-bacterial behaviors against Gram-negative and Gram-positive bacteria. The results were compared with the solubility of Ag and Cu in a buffer solution. Under similar ion concentrations, it is concluded that Ag ion or TaN-Ag is more effective against E. Coli (Gram-negative), while Cu ion or TaN-Cu is more effective against Staphylococcus aureus (Gram-positive).

Abstract: Glass and glazes are easy-to-clean surfaces often used in everyday environments where the surface needs to repel soils and deposits. In general, these surfaces have good chemical durability in everyday environments. However, the durability is rapidly degraded in solutions of high or low pH. This kind of surface corrosion has been found to diminish the cleanability. Surface topography has also a certain influence on the soil attachment and cleanability. Self-cleaning and easy-to-clean coatings have been employed to enhance the cleanability of surfaces. In this report surface properties of three coatings reported to enhance the cleanability of glass and glazed surfaces are summarized. The properties discussed are the surface appearance, roughness, wettability, soil attachment and soil removal. Also the chemical and mechanical durability of the coatings are discussed. The coatings studied were a commercial fluoropolymer film applied at room temperature, an experimental sol-gel derived TiO2 coating calcined at 500°C, and an experimental liquid flame sprayed TiO2-Ag coating applied on the substrates at 500-800°C. The advantages of the fluoropolymer coating are easy application and soil good soil repellence, but the coating has limited chemical and mechanical durability. The manufacture of the sol-gel TiO2 coating requires several processing steps. The coated surface showed excellent cleanability, and good chemical and mechanical durability. The liquid flame sprayed coating has potential to be applied online in the material manufacture. However, the processing parameters should be optimized in order to achieve desired improvements in the cleanability.

Abstract: In the present work the mechanical properties of ZnO thin films, deposited on Si (100) substrates, were studied using the nanoindentation technique. ZnO thin films were deposited by radiofrequency sputtering from a ZnO target with different H2/Ar gas mixtures. During the deposition the plasma species were in-situ monitored using optical emission spectroscopy (OES). The results showed that the introduction of H2 in the plasma phase had a strong effect on the material’s hardness and elastic modulus. The measured elastic modulus values were then related to the material density to estimate the porosity of the ZnO films. We found an increased film porosity when H2 was added to the sputtering gas, from 6% to 18% in volume. Moreover we found that the porosity was correlated by the emission intensity ratio of atomic Argon on atomic Hydrogen.

Abstract: Paper describes the experiment on manufacturing of composite basing on silicone rubber matrix filled with silica binder and kaolin and also glassy fillers. Such material is oriented on applications connected with potential fire hazard. Investigations performed on three mixes, differentiated in proportion of components, indicate potential simply way of composition of ceramizable composite.