Publications by authors named "P H Hirel"

Unlabelled: Five different interatomic potentials designed for modelling forsterite Mg SiO are compared to and experimental data. The set of tested properties include lattice constants, material density, elastic wave velocity, elastic stiffness tensor, free surface energies, generalized stacking faults, neutral Frenkel and Schottky defects, in the pressure range  GPa relevant to the Earth's upper mantle. We conclude that all interatomic potentials are reliable and applicable to the study of point defects.

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At high pressure prevailing in the lower mantle, lattice friction opposed to dislocation glide becomes very high, as reported in recent experimental and theoretical studies. We examine the consequences of this high resistance to plastic shear exhibited by ringwoodite and bridgmanite on creep mechanisms under mantle conditions. To evaluate the consequences of this effect, we model dislocation creep by dislocation dynamics.

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We use rigorous group-theoretic techniques and molecular dynamics to investigate the connection between structural symmetry and ionic conductivity in the garnet family of solid Li-ion electrolytes. We identify new ordered phases and order-disorder phase transitions that are relevant for conductivity optimization. Ionic transport in this materials family is controlled by the frustration of the Li sublattice caused by incommensurability with the host structure at noninteger Li concentrations, while ordered phases explain regions of sharply lower conductivity.

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Monoclonal antibodies (MAbs) were generated against human CD16 (Fc gamma RIII) by fusion of NS1 myeloma cells with spleen cells from BALB/c mice immunized with synthetic peptide sequences derived from the CD16 genes. After screening, four hybridomas secreting MAbs (2 IgM and 2 IgG) were selected, cloned and characterized for their activity against CD16 by ELISA test, flow cytometry, rosette inhibition and immuno-blotting. MAbs reacted strongly in ELISA with a soluble form of CD16 (sCD16) present in human serum and to a lesser degree with soluble recombinant CD16 (srCD16).

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The crystal structure of the aspartyl protease encoded by the gene pol of the human immunodeficiency virus (HIV-1, isolate BRU) has been determined to 2.7 A resolution. The enzyme, expressed as an insoluble denatured polypeptide in inclusion bodies of Escherichia coli has been renatured and crystallized.

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