Decomposition, dependence sintering

To optimize the characteristics of the electrochemical cells with multi-layer electrode, we have carried out the investigations of rate of NOx decomposition depending of the upper layer microstructure. Our investigations has shown that the best characteristics of the cells for selective NO decomposition can be reached for the electrochemical cells with the thin upper YSZ layer (2-3 xm) sintered at temperature 145CPC. 

Trillo et al. (47,137) have reported compensation behavior in oxide-catalyzed decomposition of formic acid and the Arrhenius parameters for the same reactions on cobalt and nickel metals are close to the same line, Table V, K. Since the values of E for the dehydration of this reactant on titania and on chromia were not influenced by doping or sintering, it was concluded (47) that the rate-limiting step here was not controlled by the semiconducting properties of the oxide. In contrast, the compensation effect found for the dehydrogenation reaction was ascribed to a dependence of the Arrhenius parameters on the ease of transfer of the electrons to the solid. The possibility that the compensation behavior arises through changes in the mobility of surface intermediates is also mentioned (137). 

During the heterogeneous decomposition of formic acid on copper, the active metaUic phase undergoes sintering, sublimation and modifications of surface texture [25], By comparison with the behaviour of copper(II) formate [13], it is concluded that copper(l) formate is formed. Thus variations in the values of A and E, reported for the catalytic process may be attributed to a dependence of kinetic behaviour on the lifetime of the volatile participant, and thus upon metal mobility and reaction conditions [5], The decompositions of the copper formates and the catalytic decomposition of formic acid on copper metal thus include the participation of common intermediates, but these different reactions each consist of a sequence of several interdependent processes. 

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