The Avogadro constant determination via enriched silicon-28

被引：68

作者：

Becker, P. ^{[1
]}

Friedrich, H. ^{[1
]}

Fujii, K. ^{[2
]}

Giardini, W. ^{[3
]}

Mana, G. ^{[4
]}

Picard, A. ^{[5
]}

Pohl, H-J ^{[6
]}

Riemann, H. ^{[7
]}

Valkiers, S. ^{[8
]}

机构：

[1] PTB, D-38116 Braunschweig, Germany

[2] NMIJ, Tsukuba, Ibaraki 3058563, Japan

[3] NMI, Linfield, NSW 2070, Australia

[4] INRIM, I-10135 Turin, Italy

[5] Bur Int Poids & Mesures, F-92312 Sevres, France

[6] VITCON Projectconsult GmbH, D-07743 Jena, Germany

[7] IKZ, D-12489 Berlin, Germany

[8] Commiss European Communities, IRMM, JRC, B-2440 Geel, Belgium

来源：

MEASUREMENT SCIENCE AND TECHNOLOGY | 2009年 / 20卷 / 09期

关键词：

Avogadro constant determination; kilogram redefinition; fundamental physical constants; enriched silicon-28; mass measurements; density measurements; molar mass measurements; lattice parameter measurements; volume measurements; crystal characterization; x-ray; interferometry; optical interferometry; X-RAY INTERFEROMETRY; SYNTHETIC ISOTOPE MIXTURES; OF-FLOTATION METHOD; SILICON LATTICE-PARAMETER; AMOUNT RATIO MEASUREMENTS; MOLAR-MASS; DENSITY DETERMINATION; SINGLE-CRYSTALS; PRESENT STATE; LASER INTERFEROMETERS;

D O I：

10.1088/0957-0233/20/9/092002

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

This review describes the efforts of several national metrology institutes to replace the present definition of the kilogram by a new one based on the mass of a given number of 12C atoms. This requires the determination of the Avogadro constant with a relative uncertainty no greater than 2 x 10(-8). Since in previous attempts the most significant limiting factor has been the measurement of the average molar mass of the natural silicon, an international collaboration has been set up to produce a 5 kg single crystal with an isotope enrichment over 99.985%. The technological steps enabling the production of this high-purity Si-28 crystal are also reported.

引用

页数：20

共 108 条

[81] Mass comparisons using air buoyancy artefacts [J].