光电管型分次收集器: photo tube type fraction collectorphototube type fractional collector
符: Ⅰ名词1.(符节) tally (with two halves, made of wood, bamboo, jade, metal, issued by a ruler to generals, envoys, etc., as credentials in ancient china)2.(标记; 记号) symbol; mark 短语和例子音符 musical no
