“national primary frequency standard”的概念、定义、翻译、参考文献-科学参考

单词	national primary frequency standard
释义	national primary frequency standard Encyclopedia 工学频率标准释 national primary frequency standard秒长国家计量基准直接复现秒定义的实验装置。输出的标准频率具有最高计量学特性，作为统一全国秒长量值（频率量值）最高依据的计量器具，全国只有一套。
随便看	hexosamine hexosan hexose hextetrahedron hexulose hexulose; ketohexose He Xun hexun.com hexyl circle hexyl triangle hexyl xanthate Hey He Yan heyang Heyang Qiachuan Scenic and Historic Area Heyang town Heyang Xian Heyd-Scuseria-Ernzerhof (HSE) hybrid functional Heyd-Scuseria-Ernzerhof hybrid functional heydyotis Heye Ping Heye storytelling to lotus leaf-shaped cymbals Heye Zhen He Yi He Yichun

科学参考收录了854744条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。