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We have used various techniques such as X-ray diffraction, Fourier transform infrared spectroscopy as well as dielectric measurements with a 4 GHz Microwave resonator to investigate the structure of uniaxially drawn a-polyamide 6 films. The influence of uniaxial drawing on several parameters such as degree of crystallinity, orientation and size of crystallites, permittivity and anisotropy was studied as a function of the drawing ratio. The main axis (baxis) of the polyamide 6 nano-crystals is aligned in the direction of drawing, while the hydrogen bonds (a-axis) are oriented transverse to the drawing direction. Increasing the drawing ratio yields a higher crystallinity, a better orientation of the crystallites, and a stronger dielectric anisotropy of the films. The good agreement of the results demonstrates that all the three experimental techniques are well suited to characterize the microstructure of polyamide films.

The authors evaluate the low-temperature susceptibilities, the Knight shifts, and the spin-lattice relaxation times of the hexagonal d transition metals Sc and Ru and give a detailed account of the individual contributions expressed through magnetic correlation functions. The results are in reasonable agreement with tabulated experimental data for Sc and very recent measurements for Ru.