Silica yttria-modified

We compared Pt/silica-alumina, yttria-modified silica-alumina, and fluorided alumina for n-Ci2 isomerization. Not surprisingly, increasing yttria content lowers catalyst activity at a fixed space velocity (Fig. 10). The 9% Y203/Si-Al catalyst compares closely to the 1%F/Al203 catalyst in activity. Of the catalysts evaluated here, the 9%Y203-loaded Si-Al had higher isomerization selectivity at equal conversion (Fig. 11). 

Fig. 10. n-Ci2 conversion over 0.3% Pt on silica-alumina, yttria-modified silica-alumina and F-AI2O3 at 100 psi, 12 1 H2/n-Ci2, 350°C. 

Figure 1. Isoelectric Point and Strong Hydrogen Chemisorption of. 3%Ih/Yttria Modified-Silica Alumina.

The effects of the SB in colloidal photonic crystals composed of silica spheres containing Eu - and Tb -doped yttria nanoparticles were analyzed in Ref. [64]. The profile of the emission spectra and lifetimes were modified by the presence of the SB, depending on the angle of measurement. The interesting behavior was discussed in terms of the penetration of the excitation beam into the sample volume being modulated by the SB. 

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