Hydrocarbons, molecular mobility measurement

Molecular mobility measurement, hydrocarbons in zeolites, 39 351-410 benzene... 

Molecular Mobility Measurement of Hydrocarbons in Zeolites by NMR Techniques... 

The diffusion properties of zeoUtes may be significantly influenced by their content of exchangeable cations. As an example, by both nuclear magnetic relaxation [1,143] and PEG NMR [145] measurements, the molecular mobility of aromatics in zeolite Na-X was found to be larger than in Na-Y. Since the adsorbate-adsorbent interaction of unsaturated hydrocarbons is dominated by the interaction between the n electrons of the double bonds and... 

As a byproduct of the measurements in the fully scavenged systems the sum of the mobilities of the molecular ions was determined for 10 hydrocarbon liquids varying in viscosity from 0.3 to 3 cP. As expected the values were close to linearly dependent on the viscosity of the solvent with an average value for rj[ii S ) + ld S )] of 0.75 0.25 X 10 cm /Vs with rj the viscosity in centipoise. ... 

Lindman and co-workers [21-23] demonstrated that the organisation and structure of microemulsions can be elucidated from self-diffusion measurements of all the components (using pulse-gradient or spin-echo NMR techniques). Within a micelle, the molecular motion of the hydrocarbon tails (translational, reorientation and chain flexibility) is almost as rapid as in a liquid hydrocarbon. In a reverse micelle, water molecules and counter ions are also highly mobile. 

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