In materials science, quenching is the rapid cooling of a workpiece in water, oil or air to obtain certain material properties. A type of heat treating, quenching prevents undesired low-temperature processes, such as phase transformations, from occurring. It does this by reducing the window of time during which these undesired reactions are both thermodynamically favorable, and kinetically accessible; for instance, quenching can reduce the crystal grain size of both metallic and plastic material
The length of the day in Walla Walla varies significantly over the course of the year. In 2017, the shortest day is December 21, with 8 hours, 38 minutes of daylight; the longest day is June 21, with 15 hours, 46 minutes of daylight.
CBC News Posted: Dec 20, 2011 3:11 PM ET Last Updated: Dec 19, 2013 1:13 PM ET. From Stonehenge in England to the Kokino observatory in Macedonia, people gather every year to mark the winter solstice. Dec. 21 is the shortest day of the year, in terms of daylight hours, in the Northern Hemisphere. At 12:11 p.m. ET on Dec. 21, the hemisphere begins its tilt back toward the sun, marking the winter solstice in this part of the world and slowly leading to longer days.