Phase ternary oxide

Thus, it seems to be possible to involve calcium nitride as a nitrogen source in different types of SSM reactions where ternary rare-earth nitrides would be synthesized either from appropriate mixtures of binary compounds such as oxides or chlorides, or, in some favorable cases, directly from single-phase ternary oxide (or chloride) compositions. 

ArV is not necessarily positive, and to compare the relative stability of the different modifications of a ternary compound like AGSiOs the volume of formation of the ternary oxide from the binary constituent oxides is considered for convenience. The pressure dependence of the Gibbs energies of formation from the binary constituent oxides of kyanite, sillimanite and andalusite polymorphs of A SiOs are shown in Figure 1.10. Whereas sillimanite and andalusite have positive volumes of formation and are destabilized by pressure relative to the binary oxides, kyanite has a negative volume of formation and becomes the stable high-pressure phase. The thermodynamic data used in the calculations are given in Table 1.7 [3].1... 

A number of theoretical approaches can account for the fact that an enthalpy of formation of such a binary oxide or a ternary oxide is large and negative. The stability of a ternary oxide relative to the binary constituent oxides is, however, often small, as demonstrated in Table 7.1 using Mg2SiC>4 as an example [1], The enthalpy differences between the three different polymorphs of Mg2Si04 - olivine, /3-phase and spinel - are less than 2% of the enthalpy of formation of the polymorphs. These enthalpy differences are comparable in magnitude to the enthalpy... 

Application of the phase rule to the binary (M-O) and ternary oxide system (M1-M2-O) in a closed system ... 

To conclude, we present an application of the reaction path concept and investigate the evolution of the phase boundaries in the ternary oxide system Fe-Mn-0 [Y. Ueshima, et al. (1989)]. Let us start with the a-crystal (Fe, Mn)0 which then is... 

Th02—ternary oxides or oxide phases with tetravalent americium are stabilized. The solid-state reaction of Am02 with most group V elements yields compounds with trivalent americium which are isostructural with the analogous rare earth compounds. In the last types of reactions americium exhibits a typical actinide behavior. 

Table 6. Thermodynamics at 298 K of ternary oxide, hydroxide, and carbonate mixed phases from binary components.

Propene oxidation to acrolein is carried out commercially over a range of bismuth molybdate catalysts to which are added 3-4 additional metal oxides to boost the activity. The final catalysts are mixtures of binary and ternary oxides and some solid solutions. One feature is the ability of lattice oxygen to transfer readily at the reaction temperature between the multiple phases that make up this catalyst and to the reacting propene. Another key feature is that the initial point of activation of the propene is one of the methyl C-H bonds with the production of a surface allyl intermediate, hence the term allylic oxidation. 

We have recently identified and characterized several new ternary oxides (Ce,Mo,Te)0( 3), after studying over 100 different compositions calcined in air at temperatures between 400 and 600 C. Combined with the knowledge of the (Te,Mo)0, (Ce,Mo)0, and (Ce,Te)0 chemistry, which was developed in the last decade, it is now possible to describe the complex solid-state relations of the ternary (Ce,Mo,Te)0 system. The results culminated in the identification of the active phase composition of a typical (Ce,Mo,Te)0 acrylonitrile catalyst. 

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