Topically, 1 pound of steam can be used to generate a little less than 1 pound of vapor through evaporation. 總體來說一磅的水通過蒸發可以產生不到一磅的蒸汽。
They manipulate the water in the xylem under negative pressure -- what's called a metastable liquid state -- right on the verge of becoming a vapor. 但木質部通道的兩端都結合有帶微孔的膜,這些孔能夠阻礙通道中的水超越其表面張力,發生蒸發。