We study high-pressure polyamorphism of B2O3 glass using x-ray diffraction up to 10 GPa in the 300-700 K temperature range, in situ volumetric measurements up to 9 GPa, and first-principles simulations. Under pressure, glass undergoes two-stage transformations including a gradual increase of the first B-O (O-B) coordination numbers above 5 GPa. The fraction of boron atoms in the fourfold-coordinated state at P<10 GPa is smaller than was assumed from inelastic x-ray scattering spectroscopy data, but is considerably larger than was previously suggested by the classical molecular dynamics simulations. The observed transformations under both compression and decompression are broad in hydrostatic conditions. On the basis of ab initio results, we also predict one more transformation to a superdense phase, in which B atoms are sixfold coordinated.

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A collaborative environmental eScience project produces a broad range of data, notable as much for its diversity, in source and format, as its quantity. We find that extensible markup language (XML) and associated technologies are invaluable in managing this deluge of data. We describe FOX, a toolkit for allowing Fortran codes to read and write XML, thus allowing existing scientific tools to be easily re-used in an XML-centric workflow.

The problem of enabling scientist users to submit jobs to grid computing environments will eventually limit the usability of grids. The eMinerals project has tackled this problem by developing the "my_condor_submit" (MCS) tool, which provides a simple scriptable interface to Globus, a flexible interaction with the Storage Resource Broker, metascheduling with load balancing within a grid environment, and automatic metadata harvesting. This paper provides an overview of MCS together with some use cases. We also describe the use of MCS within parameter-sweep studies.

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