单项选择题
A.甲烷B.乙烷C.丙烷D.乙烯
A.0.9999B.0.9991C.0.999D.0.998
A.石英柱B.填充柱C.分配柱D.毛细管色谱柱
A.GB/T3394-2009B.GB/T3394-2005C.GB/T3394-2007D.GB/T3392-2009
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