The Influence of Impurity upon Diffusion Constants

The role of the oxygen or oxide may be to fix the nitrogen atoms as oxides of nitrogen, which prevents the formation and subsequent evolution of molecular nitrogen. These two 

The last of this series of experiments was a study of the phosphorisation of steels. Phosphorisation occurred on heating the steel sample in a hydrogen-phosphine mixture, and concentration gradients of phosphorus into the metal were established. It was found on analysing the cpncentration-distance curves that carbon retarded the diffusion of phosphorus very strongly, and that phosphorus entering the metal swept the carbon in front of it. 

Bramley, A. and Beeby, G. Carnegie Schol. Mem, Iron and Steel Institute, 15, 71 (1926). 

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