The surface segregation of indium atoms during the growth of InGaAs/GaAs heterostructures has been investigated in situ by re ection high-energy electron di raction (RHEED). We pointed out that the strong damping of the RHEED oscillations during the deposition of InGaAs on GaAs was related to the segregation strength of indium atoms in the InGaAs layer. A simple model shows that the decay const...

We examine the level of substructure and mass segregation in the massive, young cluster Westerlund 1. We find that it is relatively smooth, with little or no mass segregation, but with the massive stars in regions of significantly higher than average surface density. While an expanding or bouncing-back scenario for the evolution of Westerlund 1 cannot be ruled out, we argue that the most natura...

We report an experimental study of a binary sand bed under an oscillating water flow. The formation and evolution of ripples is observed. The appearance of a granular segregation is shown to strongly depend on the sand bed preparation. The initial wavelength of the mixture is measured. In the final steady state, a segregation in volume is observed instead of a segregation at the surface as repo...

Segregation and mixing of dissimilar grains is a problem in many industrial and pharmaceutical processes, as well as in hazardous geophysical flows, where the sizedistribution can have a major impact on the local rheology and the overall run-out. In this paper, a simple binary mixture theory is used to formulate a model for particlesize segregation and diffusive remixing of large and small part...

We investigated the functional role of large-scale molecular segregation at the T cell-APC contact site during T lymphocyte Ag recognition. Inhibition of CD2-CD58 interaction markedly affected segregation of CD2 and CD2AP from CD45. Under these conditions, Ag-induced calcium mobilization, PKC theta; clustering at the immunological synapse, and IFN-gamma production also were inhibited. However, ...

We consider the effect of mass segregation on the observable integrated properties of star clusters. The measurable properties depend on a combination of the dynamical age of the cluster and the physical age of the stars in the cluster. To investigate all possible combinations of these two quantities, we propose an analytical model for the mass function of segregated star clusters that agrees w...

High-density polymer brushes on substrates exhibit unique properties and functions stemming from the extended conformations due to the surface constraint. To date, such chain organizations have been mostly attained by synthetic strategies of surface-initiated living polymerization. We show herein a new method to prepare a high-density polymer brush architecture using surface segregation and sel...

The macrosegregation behaviors of Al-Sn-Cu ternary immiscible alloy castings and their effects on mechanical tribological properties were investigated. results demonstrate that Sn Cu segregate in the casting simultaneously, mass fraction two elements has a “U” shaped distribution. Significantly, positive negative segregation occur casting, with appearing top lower surfaces remaining surfaces, 1...