Nano- and Microtechnology from A - Z: From Nanosystems to Colloids and Interfaces

P

Packed-Bed Scrubber

A separation device used to remove fine aerosol particles, and/or aerosol droplets, from a gas stream. Somewhat similar to an impingement-plate-tower scrubber, a packed-bed scrubber involves impaction of the droplets or particles on liquid-coated packing materials of various kinds, such as porous plates or mesh screens. The gas stream is usually made to flow upward through the packed bed. The scrubbing liquid is usually a solvent liquid and is usually made to flow downward, countercurrent to the rising gas stream. Such devices are widely used in industry. Packed-bed scrubbers are sometimes referred to as Acid-Gas Scrubbers, or Packed-Tower Scrubbers. See also Impingement-Plate-Tower Scrubber, Mist Eliminator, and Wet Scrubber.

Packed-Tower Scrubber

See Packed-Bed Scrubber.

Pad Layer Emulsion

See Interface Emulsion.

Palisade Layer

In a micelle, the region of water molecules of hydration postulated to lie between relatively water-free hydrocarbon chains at the center of the micelle and the exposed, fully hydrated polar groups at the micelle surface.

Pallmann Effect

See Suspension Effect.

PALM

Photoactivated Localization Microscopy. See Super-Resolution Microscopy and Table 14.

Palm Wax

See Carnauba Wax.

Paracasein

See Casein.

Parachor

An empirical parameter used in the estimation of the surface tension of liquids. The parachor, P = Mγ^¼/Δρ, where γ is the surface or interfacial tension, Δρ is the density difference between the phases, and ...