Experimental procedure aging condition

All experimental and surgical procedures were approved by the Animal Care and Ethics Committee of Kanazawa University. The subjects of our investigations were female Japanese macaque monkeys (Macaca fuscata). These were kept in air-conditioned cages sized approximately 1 m on a side. The monkeys were allowed free access to water and were daily fed with artificial animal food, and fruits or vegetables. In total, tissues from 29 monkeys were included in the present study one monkey was neonatal (14 days old, sacrificed on postnatal day 14 P14), while the rest of the monkeys were sexually mature (age of 5-13 years). 

These line shifts suggest the presence of Pt/Rli alloyed particles in the samples. According to Darling [6], application of Vegard s law [7] allows to evaluate the atomic rhodium concentration in alloyed phases. For cycle 1, cycle 2 and cycle 3-based procedures, these concentrations are 8%, 17% and 19% respectively. Since tlie nominal Rli/Pt+Rh atomic ratio of samples is 27%, these results indicate that whereas these two noble metals are completely miscible [6], some rhodium remains unalloyed in catalysts after ageing in the present experimental conditions. Moreover, no significant modification of the rhodium concentration in alloyed phases is detected after ageing under cycle 2 and cycle 3 conditions (17% and 19% respectively). 

The procedure of preparation by deposition-precipitation by direct addition of a base has been altered with the preparation of supported noble metals. The corresponding papers still refer to deposition-precipitation, but the procedure of preparation is different. The base is added either slowly, dropwise, or it is unspecified, so as to reach a final pH. The support can be added before or after pH adjustment. Then, the suspension ages for a given time at this pH. In other word, it turns out that the preparation is performed at a fixed pH. The supported phase is assumed to be a hydroxide of the corresponding metal (Table 14.4), which would exclusively precipitate on the oxide surface, but no characterization has been performed. Moreover, most often the experimental conditions do not allow us to know whether all the metal complex in solution is deposited onto the support. Such kind of modified procedure has also been used for the preparation of oxide supported on oxide, such as Cu on CeOj (Cuo iCeo., ), with the goal of modifying the redox properties of ceria (with NaHCOj at pH 8.5 for 2 h, probably at room temperature) (24). 

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