938.    FISCHBECK, K., AN SALZER, F.  [Change of the Catalytic Effect of Metals at the Transition Point.]  Ztschr. Elektrochem., vol. 41, 1935, pp. 158-169; Chem. Abs., vol. 29, 1935, p. 3958.

      Sharp decrease of the catalytic activity with the change into the high-temperature form was shown for (1) the decomposition of NH₃ on Fe and (2) the hydrogenation of CO₂ on catalysts of Ni 5-Co 95%, and Ni 10-Co 90%.  At the demagnetization temperature of Ni and Ni-Cu alloys, no discontinuous change of the catalytic activity was observed.  They conclude that, per unit surface, the catalytic activity of 2 forms of the same substance is different.