The first day of school in the China falls on 1 September, or the first Monday following if September 1 is a Friday, Saturday, or Sunday. In northeastern China, schools open on Monday in mid-August after summer vacation.
3) Improper heating profiles setting lead to unbalanced heating zones temperature inside heating furnace, which causes uneven glass temperature on both different parts of the glass sheet and between the top and bottom glass surfaces, thus may brings irregular white haze on glass surfaces.
Haze is traditionally an atmospheric phenomenon where dust, smoke and other dry particles obscure the clarity of the sky. The World Meteorological Organization manual of codes includes a classification of horizontal obscuration into categories of fog, ice fog, steam fog, mist, haze, smoke, volcanic ash, dust, sand and snow. Sources for haze particles include farming (ploughing in dry weather), traffic, industry, and wildfires.