De Bièvre P, Valkiers S, Peiser H S
Institute for Reference Materials and Measurements, Commission of the European Communities, Joint Research Centre, B-2440, Geel, Belgium.
National Institute of Standards and Technology, Gaithersburg, MD 20899-0001.
J Res Natl Inst Stand Technol. 1994 Mar-Apr;99(2):201-202. doi: 10.6028/jres.099.016.
New isotope abundance and relative atomic mass (atomic weight) values - with low, hitherto unattained uncertainty - are reported for two previously described silicon reference materials using a well-known method with an improved isotope-ratio mass spectrometer. These new values are directly traceable to the SI, more specifically to the unit for amount of substance, the mole, and independent of the SI unit of mass and of the Avogadro constant. Besides the residual mass-spectrometric uncertainties, these new values depend in effect only on a recently published direct comparison of the cyclotron frequency in a Penning trap of Si with that of C.
使用一台经过改进的同位素比率质谱仪，采用一种知名方法，报告了两种先前描述的硅参考物质的新同位素丰度和相对原子质量（原子量）值，其不确定性低，此前尚未达到。这些新值可直接溯源至国际单位制（SI），更具体地说是物质的量单位摩尔，并且独立于SI质量单位和阿伏伽德罗常数。除了残留的质谱不确定性外，这些新值实际上仅取决于最近发表的硅在潘宁阱中的回旋频率与碳的回旋频率的直接比较。
