The effects of dissolved atmospheric gases on the density of water are investigated by hydrostatic pycnometry, and subsequently the effect of air dissolved in water is estimated according to the contributions of the respective gases and the air composition. The calculated result agrees with the experimentally-obtained decrease of the density with a systematic deviation of less than 0.16 x kg/m3 (0.16 ppm) in the temperature range between 0 "C and 40 "C. In addition, the partial molar volumes of nitrogen, oxygen, argon, and carbon dioxide under atmospheric pressure are calculated.

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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It is shown that temperature acts to disrupt the magnetization of Peierls distorted quasi-one-dimensional materials (Q1DM). The mean-field finite temperature phase diagram for the field theory model employed is obtained by considering both homogeneous and inhomogeneous condensates. The tricritical points of the second-order transition lines of the gap parameter and magnetization are explicitly calculated. It is also shown that in the absence of an external static magnetic field the magnetization is always zero, at any temperature. As expected, temperature does not induce any magnetization effect on Peierls distorted Q1DM.

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