Through the international cooperation the metrologists are striving to redefine the mass standard depending on unchanging properties of nature based on the concept of Avogadro constant and planck's constant. 近年来,计量学家通过国际合作,试图基于自然的不变性质、阿佛加德罗常数和普朗克常数的概念重新定义质量基准。