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The thermal conductivity of the transition metals is examined with an account of the features of their electronic structure. It is shown that the thermal conductivity is governed by the form of the stable d-electron configuration, their statistical weights, their energetic stability, and by the number of collectivized electrons.

1. We have considered data available in the literature on the melting points and thermal stability of transition metal oxides (with different degrees of oxidation) in comparison with the features of the electronic structure of the transition metals and oxygen. 2. It is demonstrated that the melting points and thermal stability of the oxides are determined by the nature of the distribution of valent electrons from the components over localized and nonlocalized ones and by the probability of the formation of stable electron configurations of transition metal and oxygen atoms. The drop in statistical weight of stable configurations and increase in proportion of nonlocalized electrons results in a drop in melting point and thermal stability of the oxides.

1. The breakdown voltages of the rocks studied are comparatively low and do not exceed 270 kV for a 1 cm thickness. This means that electrical methods based on technically available energy sources can be used for rock breaking. 2. With voltage durations of 2·10−7 to 2·10−6sec, the breakdown voltages of wet rocks do not exceed those of dry rocks by more than 25%. 3. Impregnating rocks with an insulating liquid (transformer oil) increases their breakdown voltages. The relative increase in breakdown voltage depends mainly on the structure and porosity of the rock.