“…Of the various properties of thin films, a method for the determination of the density of thin metal films was proposed by Trushin et al 268 Other Russian workers 269 overcame the mutual interferences of double layer Co/Ni-Cr films on Polikor to develop a procedure for the characterisation of their structures. An Italian group 270 proposed a new compact XRF spectrometer for the determination of thickness of a coating on a substrate.…”