Hydraulic fracturing or "fracking" is a process of forcing water mixed with chemicals through deep wells to shatter and crack hard shale rocks to release the gas inside.

BBC: Hydraulic fracturing

If the star's outer layers could be mixed into the core, that would slow the process of inflation down.

ECONOMIST: Is it time for a new approach to finding extraterrestrials?

Most recycled cooking oil today is used to power diesel trucks or mixed with home heating fuel, a simpler conversion process.

BBC: Cooking oil powers transatlantic flights

She had photographed much of her work as part of her creative process, a fact that leaves her with mixed emotions.

WSJ: Pratt Fire Destroys, Inspires

Investment intentions for the year ahead were mixed, with increases in spending expected in product and process innovation but declines forecast in training and retraining and investment in buildings.

BBC: Cargo containers being unloaded

Thousands of gallons of salt water, likely mixed with minute quantities of chemicals used in the controversial but long-established fracking process have reportedly spilled out of the well and into a stream near Canton, Pa.

FORBES: Chesapeake Energy Suffers Gas Well Blowout On Anniversary Of BP Spill