Abstract
Within the IMGC project for the redetermination of the Avogadro constant (NA) through the measurement of mean molar mass, lattice spacing and density of a silicon single crystal, progress in the latter field has been achieved by establishing Solid Density Standards (SDS). A contactless interferometer was adopted to measure diameters of glass ceramic spheres. This measurement is then associated with roundness profiles to obtain the mean diameter. Mass and volume of the standards are thus traceable to mass and length standards. SDS allow measurements of about 1 ppm uncertainty, confirmed by many comparisons with standards of other laboratories. Work is in progress on absolute mass and volume measurements of silicon artifacts.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
