Using a pair bond type model for the interatomic interactions. we determine surface scgregation on clean, H, 0 and CO covered surfaces of various alloys. Furthermore, we study surface segregation caused by bulk hydrogen absorption. Numerical results are presented for Pd ,Zr, ~ H, We find, that strong surface segregation may result from chemisorption of 0 and CO and from absorption of H in the b...

Surface segregation in alloys can be influenced by the presence of adsorbed species. In this work, the effect of adsorbed sulfur on surface segregation in a Pd70Cu30 alloy was studied for sulfur coverages from zero through saturation and for temperatures from 400 to 1000 K. X-ray photoemission spectroscopy (XPS) was used to determine the alloy composition in the near-surface region ( 7 atomic l...

A widespread view is that most texture segregation can be accounted for by differences in the spatial frequency content of texture regions. Evidence from both psychophysical and physiological studies indicate, however, that beyond these early filtering stages, there are stages of 3-D boundary segmentation and surface representation that are used to segregate textures. Chromatic segregation of e...

The shock scaffold is a hierarchical organization of the medial axis ( ) in 3D consisting of special medial points, and curves connecting these points, thereby forming a geometric directed graph [7]. We will describe a new method for segregating the shock scaffold ( ) for an unorganized cloud of points in 3D in two sub-groups, one of which is used to mesh the point generators into a surface int...

Visual input is segregated in the brain into subsystems that process different attributes such as motion and color. At the same time, visual information is perceptually segregated into objects and surfaces. Here we demonstrate that perceptual segregation of visual entities based on a transparency cue precedes and affects perceptual binding of attributes. Adding an irrelevant transparency cue pa...

The surface segregation of phosphorus in relaxed Si0.7Ge0.3 epitaxial films grown on Si (100) substrates by rapid thermal chemical vapor deposition was investigated in this letter. The effect of the growth temperature on phosphorus segregation was studied experimentally and examined using a two-state model. As the growth temperature is reduced, phosphorus segregation is greatly suppressed, and ...

Erbium surface segregation is observed during growth of Er-doped Si by molecular beam epitaxy on Si~100! at 600 °C. Once a critical Er surface areal density of 2310 Er/cm is reached, enhanced Er trapping is observed, possibly due to the formation of silicide precipitates. Er segregation on Si~100! is fully avoided when growth is performed in an oxygen background pressure of ; 10 mbar, due to th...

A simple model based on the concept of a layered structure near the interface has been used to investigate the surface tension and surface segregation of SnPb and SnZn molten alloys. With increasing concentration of Sn, the surface tension (a) of SnPb alloys has been found to increase, while a of SnZn alloys decreases, a of both systems is smaller than the ideal value ZC, a,. Our study reveals ...