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Nanostructured materials consist of crystalline and grain boundary components. In the simplest case, both components are chemically identical. Here, we present the results of a study of a system consisting of a crystalline component built by A atoms (tungsten) and a grain boundary component of B atoms (gallium). Within this system, component B is in a disordered state. Most likely it exhibits an 'amorphous-like' structure, and coats the tungsten crystals uniformily with a constant thickness, thus forming a Ga skeleton structure. The non-crystalline gallium seems to undergo no first order structural phase transitions, e.g., no first order melting transition was noted when the composit was below, at or above the equilibrium melting point of Ga. The properties of gallium as grain boundary component differ significantly from those of crystalline and amorphous bulk gallium., Comment: 5 pages, 9 figures, accepted for publication in Phys.Rev.B

The project will investigate the use of radar altimetry (RA) data in the determination of the ocean circulation models. RA data will be used to verify prognostic experiments of the steady state and seasonal cycle of large-scale circulation models and the statistical steady state of eddy-resolving models. The data will serve as initial and update conditions in data assimilation experiments and as constraints in inverse calculations. The aim of the project is a better understanding of ocean physics, the determination and mapping of ocean currents, and a contribution to the establishment of ocean circulation models for climate studies. The goal of the project is to use satellite radar altimetry data for improving our knowledge of ocean circulation both in a descriptive sense and through the physics that govern the circulation state. The basic tool is a series of ocean circulation models. Depending on the model, different techniques will be applied to incorporate the RA data.