الفهرس 
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Abstract
Interest in metal-hydrogen systems has been intensified recently by, the potential of certain intermetallic compounds as hydrogen storage materials. Most of these hydrogen storing alloys are giver. an activation pretreatment before use. The effect of two different activation procedures on the hydriding behaviour of the two compounds NiZr and NiZr, was studied. In the first activation procedure (I), each compound was subjected to cyclic hydriding by cooling in hydrogen gas from 800°C down -to.room temperature; then dehydriding the formed hydride in vacuum (b.75 Torr). In the second activation method (II), each compound was repeatedly for NiZr2).The hydriding kinetics for both compounds was studied during activation as also for active compounds.
It was observed that the activation method used influenced largely the hydriding kinetics as also the reaction mechp.nisms of the activated samples. Method (I) resulted in active samples which form the monohydride according to half (NiZr) and zero (NiZr2) order reactions These reactions were found to be controlled mainly by chemisorption (low activation energies). The following equations were found to apply:
Idw).5 x 10-3Reaction rate—J 1 e-8200IRT dt NiZr dw, 4.5 x 10-2 e-4000/RT
dt NiZr2 T