VSS_FILE_SPEC_BACKUP_TYPE enumeration. The VSS_FILE_SPEC_BACKUP_TYPE enumeration is used by writers to indicate their support of certain backup operationsâsuch as incremental or differential backupâon the basis of file sets (a specified file or files).
Blue ice (aviation) Blue ice, in the context of aviation, is frozen sewage material that has leaked mid-flight from commercial aircraft lavatory waste systems. It is a mixture of human biowaste and liquid disinfectant that freezes at high altitude. The name comes from the blue color of the disinfectant. Airlines are not allowed to dump their waste tanks in mid-flight, and pilots have no mechanism by which to do so; however, leaks sometimes do occur.
The Blue Ice, photo by Charles Bonham. The Causes of Color answers the question: What causes the blue color that sometimes appears in snow and ice? As with water, this color is caused by the absorption of both red and yellow light (leaving light at the blue end of the visible light spectrum). The absorption spectrum of ice is similar to that of water, except that hydrogen bonding causes all peaks to shift to lower energy â making the color greener.