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

G

Galvani Potential

See Inner Potential.

Gangue

In mineral processing, the gangue is the unwanted portion of a raw mineral ore. In classical froth flotation, for example, the feed ore is separated into hydrophobic (valuable) particles that are floated, skimmed off in a froth, and collected. The hydrophilic (unwanted) particles that are not floated represent the gangue.

Gardner Viscometer

See Falling Ball Viscometer and Table 13.

Gas Aphrons

See Microgas Emulsions.

Gas-Atomizing Spray Scrubber

See Venturi Scrubber.

Gas Black

See Carbon Black.

Gas Coal

An obsolete term for oil shale. See Oil Shale.

Gas Dispersion

See Foam, Solid Foam, and Gas Emulsion.

Gas Emulsion

“Wet” foams in which the liquid lamellae have thicknesses on the same scale or larger than the bubble sizes. Typically in these cases, the gas bubbles have spherical rather than polyhedral shape. Other synonyms include “gas dispersion” and “kugelschaum.” If the bubbles are very small and have a significant lifetime, the term “microfoam” is sometimes used. In petroleum production, the term is used to specify crude oil that contains a small volume fraction of dispersed gas. See also Foam.

Gas-Phase Synthesis Method

Any of several fine-particle preparation methods in which one or more of the feedstock materials goes through a gas phase, nucleation, and then growth through condensation, coagulation, and/or coalescence. Examples include physical vapour deposition, chemical vapour deposition, furnace-flow ...