Sorption unsymmetrical

If Q Qa are the amounts of penetrant sorbed at time t and at equilibrium respectively for unsymmetrical sorption 144 I50> (membrane exposed to penetrant at X = 0, blocked at X = 1) we have... 

The detailed study of Ref.150,151 indicates that the information about H(y) conveyed by different kinetic regimes is in part similar and in part different. The similarity between late time permeation and symmetrical sorption kinetics has already been pointed out above. Symmetrical sorption kinetics at both short and long times are shown to reflect primarily the properties of d2H/dy2 whereas short time unsymmetrical sorption is mainly sensitive to dH/dy. For more detailed information the original papers150,15l) should be consulted. 

Zundel reports on the hydration of thin polyelectrolyte ion-exchange membranes subject to progressive increases in water sorption. Spectroscopic observations of these systems reflect the hydration of polyion charge centers in the membranes but in the presence of associated counterions, which in turn are progressively hydrated. Zundel worked with polysulfonates and found the spectra of unhydrated polymer salts the cation is attached unsymmetrically to the SOj groups. This mode of attachment leads to a loss of degeneracy in the antisymmetric vibrations. 

Talipov, S.A. Manakov. A. Ibragimov, B.T. Lipkowski. J. Tiljakov, Z.G. Sorption of ammonia, methylamine and methanol by the P3 polymorph of gossypol. Synthesis of unsymmetric monoamine derivatives of gossypol by a solid-state reaction. J. Incl. Phenom. Mol. Recognit. Chem. 1997. 29. 33-39. 

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