Corrosion-related defects in pure Al and AA 2037 Al alloy have been investigated by positron beam-based Doppler broadening energy spectroscopy. Defect profiles have been analyzed by measuring the S parameter as a function of incident positron energy up to 30 keV. When pure Al samples are immersed in 1M NaOH for various times, a significant increase in the S parameter near the surface is observed. This implies that the corrosion process involves the creation of defects and nanometer voids. In contrast, a significant decrease in the S parameter is observed after the corrosion of water-quenched Al alloy by the same method, which is interpreted as being a result of Cu enrichment near the metal-oxide interface layer.

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ChemInform Abstract The o-phosphinoylphenolates (I) are coupled with the tosylates (II) and (IV) or the bis(chloromethyl)phosphine oxide (VI) to give the dipodands (III), (V), and (VII). The monopodands (IX) and (XI) are prepared from (Ib) and the bromohydrin (VIII).

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