High surface area tungsten oxynitride has been prepared by the temperature programmed reaction (TPR) of WO3 with NH3. All samples were characterized by x-ray diffraction (XRD), nitrogen physisorption, CO chemisorption, and elemental analysis. Samples were prepared at different heating rates (β), and a Redhead analysis yielded an activation energy for nitridation of 109 kJ mol−1. A heating rate of 0.016 K s−1 gave optimal synthesis conditions. Solid state intermediates were studied by interrupting the temperature program at various stages. No distinct suboxide phases were found using XRD. The nitridation step was determined to be a continuous transformation from oxide to oxynitride. Surface area, CO uptake, and nitrogen weight % were all found to increase as the reaction progressed. Reactivity experiments showed reasonable hydrodeoxygenation (HDO) and hydrodenitrogenation (HDN) activity, but little hydrogenation (HYD) or hydrodesulfurization (HDS) activity.

Semiconducting Bi1−xPbxBaO3−δ (or BPB) glasses with x = 0 to 0.8 have been prepared by fast quenching from the melt. Interesting anomalies in the temperature-dependent polaronic conductivity and dielectric constant have been observed in all these glass compositions at temperatures, Tp, varying from 310 to 330 K (depending on Pb concentration). This nonlinear behavior is considered to be associated with the local ordering or the displacements of the BiO3 type pyramidal structural units present in the glass matrix (observed from the infrared spectra of these glasses). This type of ordering/displacement gives rise to a local instability in the glass network structure which is also supported by the observed heat capacity anomaly around the same temperatures Tp.

The densification behavior of cordierite glass-ceramic films constrained on a rigid silicon substrate was studied in the temperature range from 900 °C to 1000 °C. An optical setup was used to obtain the thickness versus time profiles and in-plane stresses of the constrained glass-ceramic during isothermal sintering. The thickness profiles showed a rapid shrinkage due to sintering followed by an expansion corresponding to crystallization of the glass-ceramic. Measurements of in-plane stresses in constrained-sintering films showed a rapidly rising tensile stress during densification followed by a slight drop during crystallization. In films sintered above 950 °C, the tensile stress rose rapidly again near the end of crystallization, suggesting a further densification in a mostly crystallized film. Scanning electron microscope (SEM) micrographs of the film cross sections revealed the formation and growth of large pores along the interface between the glass-ceramic and silicon substrate that may have contributed to the observed film expansion. These pores are substantially larger than the initial pore size in the films, indicating that they were formed during sintering. We believe that poor wetting of the glass-ceramic on silicon may have contributed to the formation of the porous structure at the interface.

Pure vapor-grown carbon nanofibers (VGCNF's) with controllable diameters of 10–200 nm were prepared by an improved floating catalyst method. Through transmission electron microscopy (TEM) observation, it was found that VGCNF's have a duplex structure, a hollow and high-crystallinity graphite filament called primary carbon fiber surrounded by a pyrocarbon layer with low graphite crystallinity. It was observed using high-resolution TEM that VGCNF's have excellent graphitic crystallinity with graphite layers stacked neatly parallel to fiber axis. Moreover, x-ray diffraction results showed that the graphitic crystallinity of carbon fibers became higher with decreasing diameter of carbon fibers.