Oxide-ion conductors have found applications in various electrochemical devices, such as solid-oxide fuel cells, gas sensors, and separation membranes. Dion-Jacobson phases are known for their rich magnetic and electrical properties; however, there have been no reports on oxide-ion conduction in this family of materials. Here, for the first time to the best of our knowledge, we show the observation of fast oxygen anionic conducting behavior in CsBi 2-Ti 2 NbO 10−δ. The bulk ionic conductivity of this Dion-Jacobson phase is 8.9 × 10 −2 S cm −1 at 1073 K, a level that is higher than that of the conventional yttria-stabilized zirconia. The oxygen ion transport is attributable to the large anisotropic thermal motions of oxygen atoms, the presence of oxygen vacancies, and the formation of oxide-ion conducting layers in the crystal structure. The present finding of high oxide-ion conductivity in rare-earth-free CsBi 2 Ti 2 NbO 10−δ suggests the potential of Dion-Jacobson phases as a platform to identify superior oxide-ion conductors.

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The objective of this study was to localize the actin-binding site in the smooth muscle myosin light chain kinase. Limited proteolysis by thermolysin indicated that hydrolysis of the kinase at the N-terminal end of the molecule resulted in loss of actin-binding ability. Various methods of cleavage were investigated for the generation of a discrete actin-binding peptide. The method chosen was cleavage at the cysteine residues by the 5,5'-dithiobis(2-nitrobenzoic acid)-cyanide complex. This procedure yielded an actin-binding peptide of approximate M(r) 17,000. The peptide was purified and shown to possess the actin-binding properties of the native myosin light chain kinase. The binding constant of the isolated peptide and parent enzyme to actin was estimated as 7.5 x 10(4) M-1. From the amino acid composition of the peptide and comparison with the sequence of gizzard myosin light chain kinase, it was suggested that the actin-binding site is located within the N-terminal sequence 1-114. Comparison with other actin-binding proteins shows some similarities to gizzard alpha-actinin and caldesmon.

Unlike the actomyosin paste, white croaker meat paste showed poor elastic gel when heated around 60°C. The hydrolysis of muscle protein by muscle proteinase was observed in the poor gel. There are at least four kinds of proteinases in white croaker muscle: cathepsin D, neutral proteinase, calpain and alkaline proteinase. Among them only alkaline proteinase could act at pH of meat paste and around 60°C. Above facts confirmed the previous work that the heat-stable alkaline proteinase is probably implicated in the textural degradation of fish meat gel around 60°C.