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Aromatic compounds in trifluoroacetic acid were readily carboxylated with CO in the presence of a catalytic amount of palladium(II) acetate under mild conditions to give aromatic carboxylic acids in good yields.

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Synopsis : Viscosity of CaO-SiO 2 -R 2 O system at elevated temperature has been systematically evaluated with a rotating-crucible viscometer over the wide range of temperature, which includes the region of solid-liquid coexistence, so called "multi-phase". It was found that the viscosities of CaO-SiO 2 -R 2 O melts increased with temperature decrease, and were described with Arrehnius type temperature dependence between 20-100°C range of temperature below the liquidus. The rheological characterization of CaO-SiO 2 -R 2 O melts had a transition from Newtonian to non-Newtonian fluid at a given temperature, which was classified as Bingham fluid according to the relationship between the shear rate and the shear stress calculated based on the experimental condition and the viscosity data. It was unveiled that the crystallization behavior controlled the changes in the Bingham yield stress t B of CaO-SiO 2 -K 2 O multi-phase fluxes with temperature decrease. The gradual increase of t B was attributed to the crystallization of the super-cooled melt with the dispersed fine grains. The devitrification with the course dentritic crystals caused the steep increase of t B .

Synopsis : Viscosity of multi-phases fluids, suspensions of spherical polyethylene beads dispersed in silicone oils, has been measured by rotating cylinder method. Results were obtained as functions of the volume fraction and the average particle size of dispersed beads, the viscosity of silicone oil and shear rate at the surface of rotating spindle. In addition, the rheological characterization of the multi-phase fluids was examined from the relationship between the shear rate and the shear stress calculated on the basis of experimental conditions and the viscosity data. The apparent viscosities of the multi-phases fluids were found to increase exponentially with increasing the volume fraction of polyethylene beads. Moreover, in the case of the volume fraction of beads were higher than 0.3, the viscosity of these fluids decreased with increasing the shear rate. The relationships between shear stress and shear rate indicated that the highly concentrated fluids with the beads (the volume fraction of the beads were higher than 0.3) behaved as non-Newtonian fluids that were categorized as Bingham fluid.