Rare earths lanthana-supported

In some respects the rare earths are almost like oxides of isotopes of the same metal. In other respects they differ in ways that are so subtle as almost to defy understanding. Data will be presented for extrinsic field effects at relatively high and low fields over most of the rare earths in normal (referred to here as self-supported ) form and also in lanthana-supported form. One example of a rare earth in alumina-supported form will be given. 

Fractional Rate Changes for Self-Supported and Lanthana-Supported Rare Earths at 298 K in a Field of 40 Oe... 

Excepting Gd203/La203 all lanthana-supported rare earths show a negative field effect at about 40 Oe, but this becomes more nearly positive at 10 kOe. The same is true of Tb203/Al203. 

Materials which have extremely low volatility and the potential to serve therefore as non-reactive substrates and supports include zirconia, titania, and alumina. The rare earth oxides, represented by lanthana and ceria, also show very low volatility and can be expected to resist vapor-transport-assisted sintering and corrosion. Of the alkaline earth oxides, MgO is superior to all others, although the alkaline earth aluminate complex oxides can be much more stable (e. g., by a factor of 1000 for BaO) than the alkaline earth oxides. 

On many supports, ruthenium converts synthesis gas with high selectivity into lower alkanes, notably methane.. However, when ruthenium is supported on certain basic oxides, such as lanthana and ceria, highly selective production of lower olefins has been reported (1,2). One of the aims of this research was to improve the activity and selectivity of ruthenium supported on rare earth oxides (REO). As commercially available REO are of low surface area (<15m2g"l), routes to higher surface area materials have also been developed (3). 

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