Abstract: Titanium dioxide coatings were deposited by utilizing
atmospheric plasma spraying (APS) system. The agglomerated nanopowder
and different spraying parameters were used to determine
their influences on the microstructure surface feature and photoabsorption
of the coatings. The microstructure of as-sprayed TiO2
coatings were characterized by scanning electron microscope (SEM).
Surface characteristics were investigated by Fourier Transform
Infrared (FT-IR). The photo absorption was determined by UV-VIS
spectrophotometer. It is found that the spray parameters have an
influence on the microstructure, surface feature and photo-absorption
of the TiO2 coatings.
Abstract: The presence of cold air with the convergent
topography of the Lut valley over the valley-s sloping terrain can
generate Low Level Jets (LLJ). Moreover, the valley-parallel
pressure gradients and northerly LLJ are produced as a result of the
large-scale processes. In the numerical study the regional MM5
model was run leading to achieve an appropriate dynamical analysis
of flows in the region for summer and winter. The results of this
study show the presence of summer synoptical systems cause the
formation of north-south pressure gradients in the valley which could
be led to the blowing of winds with the velocity more than 14 ms-1
and vulnerable dust and wind storms lasting more than 120 days.
Whereas the presence of cold air masses in the region in winter,
cause the average speed of LLJs decrease. In this time downslope
flows are noticeable in creating the night LLJs.