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.
Each time the moon moves into line with the earth and the sun a new month begins and this is called 'Chu Yi' or 'Shuo Ri' (the first day of a lunar month). The longest day of a year or Summer Solstice falls on the 21st or 22nd of June, and the shortest day is the Winter Solstice on either December 21, 22, or 23. Using these two annual events the year was divided into in 24 equal parts, each forming the 24 solar terms.