EN ISO 6974-4-2001 天然气.用气相色谱法测定规定的不确定度的组分.第4部分:用两柱测定实验室和在线测量系统用的氮,二氧化碳和C1至C5和C6+的烃类
Natural Gas - Determination of Composition with Defined Uncertainty by Gas Chromatography - Part 4: Determination of Nitrogen, Carbon Dioxide and C1 to C5 and C6+ Hydrocarbons for a Laboratory and On-Line Measuring System Using Two Columns