Moldover Michael R
National Institute of Standards and Technology, Gaithersburg, MD 20899-0001.
J Res Natl Inst Stand Technol. 1998 Mar-Apr;103(2):167-175. doi: 10.6028/jres.103.011. Epub 1998 Apr 1.
We consider the feasibility of basing a pressure standard on measurements of the dielectric constant and the thermodynamic temperature of helium near 0 °C. The pressure of the helium would be calculated from fundamental constants, quantum mechanics, and statistical mechanics. At present, the relative standard uncertainty of the pressure () would exceed 20 × 10, the relative uncertainty of the value of the molar polarizability of helium calculated . If the relativistic corrections to were calculated as accurately as the classical value is now known, a capacitance-based pressure standard might attain () < 6 × 10 for pressures near 1 MPa, a result of considerable interest for pressure metrology. One obtains by eliminating the density from the virial expansions for and - 1. If - 1 were measured with a very stable, 0.5 pF toroidal cross capacitor, the small capacitance and the small values of - 1 would require state-of-the-art capacitance measurements to achieve a useful pressure standard.
我们考虑了基于对接近0°C的氦的介电常数和热力学温度的测量来建立压力标准的可行性。氦的压力将根据基本常数、量子力学和统计力学来计算。目前，压力（）的相对标准不确定度将超过20×10，即氦的摩尔极化率值的相对不确定度。如果对的相对论修正能像现在已知的经典值那样精确计算，对于接近1MPa的压力，基于电容的压力标准可能达到（）<6×10，这一结果对压力计量具有相当大的意义。通过从和 - 1的维里展开式中消除密度来获得。如果用一个非常稳定的0.5 pF环形交叉电容器测量 - 1，小电容和 - 1的小值将需要最先进的电容测量技术来实现一个有用的压力标准。
