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The electrical double layer. Diffuse Layer. Bulk Solution. IHP. OHP. -. +. -. +. +. f d. -. Potential. -. +. +. -. -. -. +. +. +. +. -. f i. +. -. -. -. -. +. +. -. +. +. -. distance. z : zeta potential k : liquid conductivity m : viscosity
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The electrical double layer Diffuse Layer Bulk Solution IHP OHP - + - + + fd - Potential - + + - - - + + + + - fi + - - - - + + - + + - distance
z: zeta potential k : liquid conductivity m: viscosity e : liquid permittivity DP: pressure difference from inlet to outlet fs: measured streaming potential
z: zeta potential • k : liquid conductivity • n: kinematic viscosity • : liquid permittivity a: disk radius z: distance of reference electrode from sample • : rotation rate fs: measured streaming potential
The plane of shear Diffuse Layer Bulk Solution IHP OHP - fd + z - + + - Potential + - - + - + + + - + - - - + - - + + + - - + distance Plane of shear (possibly)
A schematic of the parallel plate capillary system. voltmeter Sample solid Liquid Reference electrode (e.g. Ag/AgCl) piston/pump receptacle
Liquid Reference electrode Sample solid Schematic of the rotating disk system voltmeter
z: zeta potential R: gas law constant T: temperature z: 1, for a 1:1 salt F: faraday’s constant l: Debye length q2:charge density of the diffuse layer e: permittivity of water