中央: centre; middle频率: frequency; rate标准: standard; criterion; benchma ...副频率标准: secondary frequency standard频率标准: fs frequency standard原频率标准: primary frequency standard铷频率标准: rubidium freqnency standard基本频率标准: primary frequency standard精确频率标准: precision frequency standard量子频率标准: quantum frequency standard美国频率标准: united states frequency standards一级频率标准: primary frequency standard原子频率标准: atomic frequency standard氨分子频率标准: ammonia molecular frequency standard国内主振频率标准: national master frequency standard晶体管化频率标准: transistorized frequency standard气体池频率标准: gas-cell frequency standard时间和频率标准: time and frequency standard实验室的频率标准: laboratory standard of frequency实验室频率标准: laboratory frequency standard; laboratory standard of frequency无源原子频率标准: passive atomic frequency standard原子束频率标准: atomic beam frequency standard原子谐振频率标准: atomic resonance frequency reference铯射束频率标准: caesium beam frequency standard铵分子束频率标准: ammonium molecular beam frequency standard
