helium I

helium-i的词性：
n.（名词）

1. Liquid helium existing as a normal fluid between the superfluid transition point of approximately 2.2⁼K at 1 atmosphere pressure and its boiling point of 4.2⁼K.
（低温物理学用语）氦Ｉ：液体氦，以普通液体形式存在于超流体之间，一个大气压下其转变点约为2.2⁼K，沸点为4.2⁼K