母离子扫描模式是扫描共同（指定）子离子的所有母体（母离子），通常也用于结构解析。 This resulted in the measurement of the foot different amongst 250 mm and 335 mm before when compared to The present definition of 304.8 mm. Though The usa is among the handful of, if not simply, nations by which the foot is still extensively utilised, several countries utilized their https://charlesn788spk5.wikicorrespondent.com/user