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Several syntheses have been performed to allow the growth of zeolite crystals on α-silicon carbide supports (α-SiC). Silicon-carbide foams exhibit a duplex macroporous structure. MFI and ANA zeolites have been successfully coated on this relatively inert material. While the synthesis of MFI/SiC required the presence of an additional Si-containing source, in contrast, ANA/SiC composites have been unexpectedly obtained through the self-recrystallization of the silicon contained in the α-SiC substrate. In addition, the size of icositetrahedral ANA crystals was controlled to nearly 35 μm, thanks to SiC open cells templating effect. The different composite materials were thoroughly characterized by SEM, complete textural analysis and XRD. The amount of zeolite coating as well as the coverage by ANA zeolite crystals on SiC surface were determined by both SEM observations and adsorption measurements.

Fatigue strength and life of weldment at high temperatures are important for the materials in power plants. The fatigue crack growth rate is accelerated by oxidation. Similarly, the high-temperature fatigue life is influenced by oxidation. The base metal, the weld metal and the heat-affected zone (HAZ) of the P122 (Cr–Mo steel) weldment were oxidized between 600 °C and 700 °C for up to 500 h in air, and their oxidation behavior was examined. The oxidation resistance increased in the order of HAZ, base metal and weld metal. The scales were mainly Fe 2 O 3 . Fatigue tests were performed to measure the fatigue crack growth rate in the range of low stress intensity factor, and the results are discussed from the viewpoint of different microstructures and oxidation.

Starting from elemental bismuth, tellurium and selenium powders, n-type Bi 2 Te 2.85 Se 0.15 solid solution with fine microstructure was prepared by mechanical alloying (MA) and plasma activated sintering (PAS) in the present work. The effect of PAS process on microstructure and thermoelectric properties of the sintered samples was investigated. The sintering temperature of PAS process (683 K) was 80–100 K lower than that of conventional hot pressing and the whole PAS process was also greatly shortened to about 30 min. A preferentially orientated microstructure with the basal planes (0 0 l ) perpendicular to pressing direction was formed in the PASed sample and the maximum figure of merit ( Z ) at room temperature was 1.80 × 10 −3 K −1 .

A method by which the three-dimensional displacements and strains (stresses) of a vibrating clamped rectangular cantilever plate can be calculated from three interferograms is presented. The three-dimensional displacements and strains obtained by the time-averaged holographic interferometry are compared with those calculated by the finite element method. There is good agreement between the two.

For 3 minute umbral oscillations we have considered a two-mode resonant model with the resonance of each mode occurring separately in cavities of the photosphere and chromosphere. The model has been investigated by calculating the transmissions of the waves propagating through the cavities of the umbral photosphere and chromosphere of 3 different model atmospheres (Staude, 1982; Beebe et al. 1982; Avrett 1981). The computed resonant periods, transmission spectra and kinetic energy density of the waves associated with the oscillations are presented for comparison with observations.