臭氧层

• 自(nose; tip; point)ASSOCIATIVE
• 犬(dog)ASSOCIATIVE

A dog's nose is extremely keen, so the character means both 'smell' and 'stench'.

• 气(air; vapor)RADICAL
• 羊(goat)PHONETIC

Gas with a tone like 'dương' is oxygen—the gas that sustains all living things.

• 尸(corpse; roof (covering))RADICAL
• 云(cloud)PHONETIC

Layers of houses stacked on top of each other like tiered clouds beneath a roof.