Powder technology, clusters

A more detailed analysis of these fluctuations shows, however, that there often exist some periodicities in this behaviour which in some cases can be understood as shell closings, geometric [63] or electronic [64], with the appearance of so-called magic numbers . Studies of clusters composed of a few hundred or up to thousands of atoms [65,66] also showed that the periodicity could be extended with the existence of a new type of shells known as supershells representing a transition from pure quantum phenomena towards the limit of large quantum numbers, where a correspondence should exist between classical and quantum motion [71,72]. We will also see how there will be connections to powder technology [50,57,58] and to the mesoscopic world of nanotechnology with a two-dimensioned electron gas [73-75]. In addition to these clusters characterized by shell structure also very unique species of carbon have been... 

Cocco, R., Shaffer, E, Hays, R. et al. (2010) Particle clusters in and above fluidized beds. Powder Technology, 203, 3-11. 

Shuyan, W., Lijie, Y., Huilin, L., Long, Y., Bouillard, J., Zhenhua, H. (2009). Numerical analysis of interphase heat and mass transfer of cluster in a circulating fluidized bed. Powder Technology, 189(1), SI-96. 

Hagiwara, Y., Murata, T., Tanaka, M., Fukawa, T. (2002). Turbulence modification by the clusters of settling particles in turbulent water flow in a horizontal duct. Powder Technology, 125(2-2), 158-167. 

The research field of metal-oxide interfaces is very active, partly because of their important technological applications. For example, in heterogeneous catalysis, oxide powders or porous compounds, such as zeolites, are used as supports for transition metal clusters, because they provide a large - external or internal - specific area of contact with the metal. In many cases, it is also recognized that they modify the cluster reactivity (Dufour and Perdereau, 1988). Oxide surfaces, such as those of MgO or SrTiOs, whose quality and planarity are well controlled, have been used as substrates for the deposition of thin superconductor films. This has been particularly important since the discovery that some copper oxide based compounds remain superconductors above liquid nitrogen temperature. Thin metallic films are also deposited on various oxides in the fabrication of optical devices, or on glass in the fabrication of mirrors. 

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