natural color 自然色；天然色；本色natural coke 天然焦炭natural circulation waste-heat boiler [經(jīng)濟學]自然循環(huán)廢熱鍋爐natural circulation evaporator 自然循環(huán)蒸發(fā)器natural circulation 自然循環(huán)natural childbirth n. 自然分娩；不用葯物的分娩natural centrism [哲學]自然中心主義natural calamity [環(huán)境][辳] 自然災害；天災natural building sand [土木建築工程]天然建築砂natural building natural brown kraft wrapping paper [經(jīng)濟學]本色牛皮包裝紙natural bristle 天然鬃毛natural bridge state park natural breadth [物理學]自然寬度natural boundary condition [數(shù)] 自然邊界條件natural boundary [數(shù)] 自然邊界natural blood relation [法學]自然血親natural bitumen 天然瀝青natural biotic community [能源科學技術]自然生物群落natural bile acid resources [地球科學]天然膽酸類資源