Dynamics at Surfaces : Probing the Dynamics of Polar and A-Polar Liquids at Silica and Vapour Surfaces
نویسندگان
چکیده
Recent studies by Nuclear Magnetic Resonance and Neutron Scattering of the dynamics and phase-fractions of water/ice systems in templated porous silicas (SBA-15) indicate that what was believed to be a non-frozen surface water layer is actually plastic ice, the quantity varying (continuously and reversibly) with temperature, and converting to a brittle (mainly cubic) ice at lower temperatures. Current research relates to the study the dynamics of polar water/ice and a-polar organics at both solid and vapour interfaces. The polar results are significant for water/ice systems in the environment, where snow-packs, glaciers and icebergs are common examples of water/ice systems with extensive air/vapour interfaces. This research also points the way forward for wide-range cryoporometric metrology in ’difficult’ systems such as high iron content clays and rocks, as well as aged concrete. Results are presented for cryoporometric measurements on meteorite samples with a significant metallic content, exhibiting T ∗ 2 relaxation times down to 2.5ms.
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