Heterogeneous aggregation in binary colloidal alloys

Molecular dynamics (MD) simulation has been employed to study the nonequilibrium structure formation of two types of particles in a colloidal suspension, driven by type-dependent forces. We examined the time evolution of structure formation as well as the structural properties of the resulting aggregation by studying the radial distribution function (RDF). The resulting aggregation is well described by a binary colloidal gelation. We compared the structural properties to those for one type of particles. From the MD results, it is evident that there are significant differences between the RDF's of the two cases. Moreover, we found that the average coordination number is generally larger in the monodisperse case for all area fractions considered. Thus, by means of heterogeneous aggregation, it is possible to obtain a wide variety of structures while more close-packed structures are formed for monodisperse colloidal aggregation.Comment: 15 pages, 5 eps figures; preliminary results have been reported at the APS March Meeting 2002; accepted by Physica

Binary Colloidal Alloy Test-5: Aspheres

The Binary Colloidal Alloy Test - 5: Aspheres (BCAT-5-Aspheres) experiment photographs initially randomized colloidal samples (tiny nanoscale spheres suspended in liquid) in microgravity to determine their resulting structure over time. BCAT-5-Aspheres will study the properties of concentrated systems of small particles when they are identical, but not spherical in microgravity.

Space

256 hal : il. ; 36 c

The new solar system

240 p. : il.; 27 cm

A positron named Priscilla: scientific discovery at the frontier

This volume reports on some of the most exciting recent discoveries and advances in fields from astronomy to molecular biology. Each chapter is authored by a popular science writer who offers historical perspectives, explanations of current scientific thinking and previews of future developments

The new solar system

+224hlm.;28c