Morphologies, petrographic settings and carbon and nitrogen isotopic compositions of graphites in the Acapulco meteorite, the latter determined by secondary ionization mass spectrometry, are reported. Seven different graphite morphologies were recognized, the majority of which occur enclosed exclusively in kamacite. Individual graphite grains also rarely occur in the silicate matrix. Kamacite r...

We present a report on the status of 107Pd (>r = 9.4 x 106 y) in the early solar system and the implications of its presence for protoplanet evolution. Over the last two decades we have carried out an extensive search for the evidence of presently extinct 107Pd in meteorites. From these results we conclude that: 1) 107 Ag* (excess 107 Ag) is present in a wide variety of iron and stony-iron mete...

DTA measurements with mixtures of aluminum oxide and lutetium oxide around the 1:1 perovskite composition were performed up to 1970 C. A peak with onset 1901 C was due to the melting of the eutectic Lu4Al2O9 (monoclinic phase) and LuAlO3 (perovskite). Neither peritectic melting of the perovskite nor its decomposition in the solid phase could be resolved experimentally. The maximum of the eutect...

We have studied the dewetting of thin liquid metal films (Au, Cu, Ni) on fused silica substrates which occurs after melting with a Q-switched laser pulse. Optical microscopy, scanning electron microscopy, and scanning near field acoustic microscopy reveal two distinctly different modes of the dewetting process: On one hand, we observe heterogeneous nucleation of “dry” circular patches, which gr...

The present study deals with the properties of five different metals/alloys (Al-12Si, Cu-10Sn and 316L—face centered cubic structure, CoCrMo and commercially pure Ti (CP-Ti)—hexagonal closed packed structure) fabricated by selective laser melting. The room temperature tensile properties of Al-12Si samples show good consistency in results within the experimental errors. Similar reproducible resu...

Temperature-dependent dynamics of monolayer-protected Au and Ag nanoclusters and silver thiolates have been investigated with quasielastic neutron scattering. The simplest motion in these systems is the uniaxial rotation of the chain, which evolves slowly with temperature. While longer chain monolayers (above C8) on Au clusters are rotationally frozen at room temperature, dynamic freedom exists...

Terrestrial oceanic and continental basalts are enriched by approximately þ0.1% in Fe/Fe ratio relative to primitive, undifferentiated meteorites (chondrites). The dFe values of terrestrial basalts are also distinct from those of basalts from Mars and asteroid Vesta, which have chondritic Fe isotopic compositions. The processes responsible for the isotopic enrichment of terrestrial basalts are ...