Titanium and its alloys are widely used in aircraft, rocket production, shipbuilding, machine industry, chemical and food industry, medicine due to their high specific strength, good corrosion resistance and biological passivity. However, titanium has properties which limit its application as construction material. Particularly, tendency to surface adhesion and galling at friction results in it...

The fundamentals of catalyst deactivation are presented in this review. The chemico-physical aspects concerning the various deactivation causes (i.e. poisoning, sintering, coking, solid-state transformation, masking, etc.) have been analyzed and discussed, along with the mathematical description of the deactivation phenomena. # 1999 Elsevier Science B.V. All rights

The present study reports seasonal data about chemico-physical trends, macrobenthic invertebrates, and Phragmites australis decomposition rates within a karstic freshwater system in the western classic Karst. Results presented herein were compared with those obtained from same five years ago. Chemico-physical showed higher temperatures lower levels of pH conductivity than past. invertebrate com...

this study investigates the vertical replacement of salts, variability of electrical conductivity (ec) and soil acidity (ph) due to direct electrical current. a plexiglas cylinder 100 cm in depth with a 14 cm radius was used as a soil container and filled with uniform moist soil to 90 cm. during the experiments, the bottom 10 cm of soil in the cylinder was kept saturated. a steel bar was used a...