Pacemakers used to have but a single lead, going to one of the heart’s four chambers.
以往的起搏器通常只有一根导线接入心脏四个房室中的一个。
2
The research of modeling and experiment of single droplet could reveal the fundamental mechanisms, combustion characteristics and enhance design level of combustion chambers.
单滴燃烧研究的主要应用在于揭示燃料的燃烧机理，分析燃料的燃烧特性，提高燃烧装置的设计水平。
3
Pacemakers used to have but a single lead, going to one of the heart's four chambers.