The binding of phosphonic acids at aluminium oxide surfaces and correlation with passivation of aluminium flake.

Measurements of adsorption isotherms of a series of thirteen mono- and di-phosphonic acids have shown that these bind strongly to the surface of high surface area aluminium trihydroxide. The incorporation of such phosphonates into a suspension of aluminium flake in an aqueous medium, modelling the continuous phase of a water-based paint, greatly suppresses the evolution of hydrogen. Whilst strong binding of the phosphonate to aluminium oxides is an essential criterion for good passivation, other factors such as the hydrophobicity of the ligand are also important in suppressing hydrogen-evolution.

Isolated unilateral hypoglossal nerve palsy after minor head trauma.

Isolated unilateral hypoglossal nerve palsy after fracture of the occipital condyle is rare. It usually occurs after major trauma, such as high-speed deceleration injuries following road traffic accidents. We describe a case that resulted from minor trauma. An underlying skull base malformation may have been a predisposing factor.