The photocatalytic activity of a nano-anatase-containing paint has been studied. It was found that after a certain period of initial UV irradiation, the photocatalytic activity of such a paint significantly increases. To understand the underlying mechanisms, the pigment volume concentrations (PVCs)were varied in different ways, e.g. by varying the content of the inorganic filler, or by adjusting the content of the polymeric binder. The results were compared with the photocatalytic activity of a commercially available paint. The formulations which exhibit a good compromise between photocatalytic activity and other essential paint properties are discussed. The effect of relative humidity on the photocatalytic activity was also measured and is commented upon. It was found that the photocatalytic activity of studied paints was not affected by PVC.
COBISS.SI-ID: 1817447
Intergranular stress-corrosion cracking (IGSCC) on a sensitised type AISI 304 stainless steel specimen was monitored simultaneously by acoustic emission, electrochemical noise, elongation measurements and a digital imaging system. Detection and characterisation of the stress-corrosion processes were investigated and discussed in details. The results confirm and generalise our previously established correlations between various parameters obtained by the implemented characterisation methods and IGSCC processes. Additionally, a reliable differentiation between crack related and crack non-related acoustic emission (AE) signals was made based on an analysis of the AE signals. The relationship between the crack lengths calculated by means of digital image correlation analysis and the electrochemical current noise and the relationship between crack opening displacement and measured elongation were also established.
COBISS.SI-ID: 11958043
The response of autoclaved aerated concrete confined masonry buildings to seismic ground motion has been studied. Three 1:4 scale models of residential buildings with the same distribution of walls in plan but different types of floors and number of stories have been tested on a uni-directional shaking table. Lightweight prefabricated slabs have been installed in the case of the three-storey model M1, whereas reinforced concrete slabs have been constructedin the case of three-storey model M2 and four-storey model M3. Model M1 was subjected to seismic excitation along the axis of symmetry, whereas models M2 and M3 were tested orthogonal to it. Typical storey mechanism, characterised by diagonal shear failure mode of walls in the groundfloor in the direction of excitation has been observed in all cases. Taking into consideration the observed behaviour, a numerical model with concentrated masses and storey hysteretic rules has been used to simulate the observed behaviour. Storey resistance curves calculated by a push-over method and hysteretic rules, which take into account damage and energy based stiffness degradation hysteretic rules, have been used to model the non-linearbehaviour of the structure. Good agreement between the experimentally observed and calculated non-linear behaviour has been obtained.
COBISS.SI-ID: 1837927