The temperature dependence of the recoilless fraction, f(T), has been measured for the ferrous proteins deoxymyoglobin, oxymyoglobin, carbonmonoxymyoglobin and rubredoxin in frozen solutions. The general pattern of f(T) is similar for all four proteins ; it deviates from the predictions of the Debye model, indicatine low temperature anharnonicity. Characteristic differences in dlnf/dT between myoglobin and its O2- and CO-adduct are observed. For T > 180 K ln f drops rapidly with temperature, and differences due to the solvent matrix become apparent. Diffusional line broadening is noticeable for T > 200 K in glycerol and for T > 230 K in frozen aqueous samples

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The hydrothermal decomposition of cobalt hydroxide is of importance in understanding corrosion in nuclear reactors, in the industrial production of cobaltous oxide, and potentially for thermal energy storage. The kinetics of decomposition in the presence of water vapor is poorly understood but nevertheless important in the above situations. The decomposition reaction has mainly been studied in air or inert environments. Here, we report data on the kinetics of the decomposition reaction at temperatures up to 270 °C in the presence of saturated water vapor. We show that CoO can be obtained as the decomposition product under a low dissolved oxygen level of <2 mg/L. The decomposition follows the Avrami Erofeev kinetics model with rate constants of 0.3 h −1 and 0.56 h −1 at 260 and 270 °C, respectively. In comparison, decomposition in N 2 and air environments showed much faster rates on the order of min −1 . Data reported here are important in the fundamental understanding of the reaction kinetics and in identifying the mechanism for the decomposition of cobalt hydroxide and other brucite-like hydroxides.

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