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Three new phenyl ether derivatives, 3-hydroxy-5-(3-hydroxy-5-methylphenoxy)benzoic acid (1), 3,4-dihydroxy-5-(3-hydroxy-5-methylphenoxy)benzoic acid (2), 3-[3-hydroxy-5-(hydroxymethyl)phenoxy]-5-methylphenol (3), and three known compounds 4–6 were obtained from the fermentation broth of Aspergillus carneus HQ889708, which was isolated from sea water from South China Sea. The structures of compounds 1–3 were established on the basis of spectroscopic methods including ESI-MS and NMR. Compounds 4–6 were reported before as synthesized products, herein, they are reported from nature for the first time.

The oxygen transport in the nickel-zirconia composite was investigated using the oxygen permeation method. A disk-shaped sample made of nickel (40 vol%) and yttria-stabilized zirconia (YSZ) was used to construct a permeation cell. By exposing one side of the sample to a CO2 gas stream and the other side to a CO stream at elevated temperatures, oxide ions were extracted from CO2 and transported to the other side to oxidize CO. The oxygen permeation flux through the composite was determined by analyzing the effluent from the permeation cell, and the oxygen ionic conductivity of the composite was derived from the permeation data and the oxygen partial pressures. It was shown that the oxygen ionic conductivity of the composite YSZ fraction was about one third of that for the single-phase zirconia ceramic, and the activation energy associated with the transport of oxide ions in the composite is somewhat greater than that of the single-phase zirconia.

A method based on the X-ray diffraction intensity ratio was developed to determine the maximum deficiency that the perovskite-structured La1−xMnO3±δ can accommodate at the A-site. Computer simulation predicts that the intensity ratio of (024) and (012) reflections for La1−xMnO3±δ in hexagonal setting increases with increasing the La deficiency x. XRD analysis shows that with increasing x until 0.09, the ratio increases as predicted, then levels off with further increase in x. An abrupt change in electrical conductivity is also observed at x of ∼0.10. It is concluded that the maximum deficiency lies in between 0.09 and 0.10 for La1−xMnO3±δ. The methodology presented in this paper in principle can be applied to other perovskite-structured materials.