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Some synthetic and natural materials exhibit anisotropic features due to the way that they have been fabricated. Small-angle scattering techniques with x-rays or neutrons may be used to probe this anisotropy by observation of the azimuthal variation in scattering intensity from an oriented sample. Results will be presented for a series of materials, in either fibre or disk form, which give distinctive patterns corresponding to ordered or disordered structures with spatial characteristics in the 10-2000 Angstrom range. The possible extension of the method to other materials and further development of the technique is also considered.

Small-Angle X-Ray Scattering (SAXS) studies have been carried out over a wide range of Q-values (5 x 10(-3) - 0.5 Angstrom(-1)) permitting analysis of structural features for a spatial regime of 0.5-200 nm. Experimental and analysis procedures are described and results presented for a series of activated carbons. It is found that the pore size distribution has a complex form that varies according to the degree of activation (burn-off). Additional measurements have been made by neutron diffraction. The results demonstrate the basic graphitic structure of the carbons but show that there is considerable distortion of lattice planes.