the use of fe-al intermetallic compound coatings has been investigated in order to improve the tribological behaviour of carbon tool steel. the coatings were formed by a pack cementation process and subsequently diffusion annealing at 900˚c in an argon controlled atmosphere. the optimum diffusion time was selected on the basis of optimum thickness and tribological behaviour. the microstructure ...

The sedimentation of an isolated, charged polyelectrolyte (PE) subjected to an applied field is modeled theoretically, taking into account the variation of its shape. In particular, the effects of double-layer relaxation, effective charge density, and strength of the induced relaxation electric field are examined. We show that the interaction of these effects yields complex and interesting sedi...

Presence of salts in water has been one of the biggest problems of industrial equipment such as evaporators, boilers, and pipes. These salts gradually form scales on evaporators and boilers tubes and reduce their efficiency. Pretreatment processes are conducted to remove these salts; with sedimentation tanks being one of the essential equipment used in these processes. This study numerically si...

-Flotation coefficients are usually determined from data obtained under high pressure (cell bottom) conditions. A power series expansion is proposed for correction to atmospheric pressure (meniscus) conditions. The same expansion may be applied to the concentration correction of flotation coefficients. From sedimentation experiments with polymer solutions in the analytical ultracentrifuge, we c...

This paper presents the directed sedimentation of suspension particles in a thin layer of liquid ( 1 mm) onto a featureless glass substrate by Marangoni flows. A programmable 16 × 8 array of surface mount resistors suspended 0.1–2 mm above the liquid provides dynamic millimeter-sized heat sources to locally heat the liquid surface to temperatures from approximately 28.5 to 36.5 ◦C. The heaters ...

Abstract Erosion and sedimentation are the most complicated problems in hydrodynamic which are very important in water-related projects of arid and semi-arid basins. For this reason, the presence of suitable methods for good estimation of suspended sediment load of rivers is very valuable. Solving hydrodynamic equations related to these phenomenons and access to a mathematical-conceptual mode...