Mobility gradient

The development of the spacer technique in isotachophoresis has been associated in the first place with its application in the field of proteins as a spacing mobility gradient established with the aid of carrier ampholytes . 

Mobility Gradient of Polystyrene in Films Supported on Solid Substrates... 

Fig. 10 Possible model for depth dependence of Tg as a function of Mn, showing the mobility gradient in the surface region. Within the depth region in which chain ends are segregated, the mobility gradient should be strongly dependent on M. This would be not the case far beyond the segregated surface layer of chain ends...

Thermal molecular motion of PS at surfaces and interfaces in films was presented in this review. We clearly show that chain mobility at the surface region is more mobile than in the interior bulk phase and that chain mobility at the interfacial region is less than in the interior phase. This means that there is a mobility gradient in polymer films along the direction normal to the surface. This gradient can be experimentally detected if the ratio of the surface and interfacial areas to the total volume increases, namely in ultrathin films. 

A series of ID and 2D NMR experiments performed on nanocomposites of hectorite, a smectite clay mineral, showed new opportunities for studying large assemblies of layered minerals with polymeric materials.In particular. rotational-echo double-resonance (REDOR) experiments afforded H- Si distances with precision, and a mobility gradient of intercalated polyethyleneoxide (PEG) segments was demonstrated in H-" Si wideline separation (WISE) experiments. 

Fig. 6 Stmcture and dynamics of directing dendrons in cylindrical supramolecular macromolecules. (a) Local packing allows the formation of helices, (b) Restricted motion, as indicated by high dynamic order parameters, with a mobility gradient inside-out. Adopted from [83]...

Napolitano S, Wiibbenhorst M (2007) Deviation from bulk behaviour in the cold crystallizatirai kinetics of ultrathin films of poly(3-hydroxybutyrate). J Phys Condens Matter 19 205121 Napolitano S, Capponi S, Vanroy B (2013) Glassy dynamics of soft matter under ID confinement how irreversible adsorption affects molecular packing, mobility gradients and orientational... 

Mirigian, S., Schweizer, K.S. Communication slow relaxation, spatial mobility gradients, and vitrification in confined films. The Journal of Chemical Physics 141(16), 161103 (2014)... 

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