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。
