Mettler Dictionary Of Weighing Terms

This Dictionary of Weighing Terms is a comprehensive practical guide to the terminology of weighing for all users of weighing instruments in industry and science. It explains more than 1000 terms of weighing technology and related areas; numerous illustrations assist understanding. The Dictionary of Weighing Terms is a joint work of the German Federal Institute of Physics and Metrology (PTB) and METTLER TOLEDO, the weighing instruments manufacturer. Special thanks go to Peter Brandes, Michael Denzel, and Dr. Oliver Mack of PTB, and to Richard Davis of BIPM, who with their technical knowledge have contributed to the success of this work. The Dictionary contains terms from the following fields: fundamentals of weighing, application and use of weighing instruments, international standards, legal requirements for weighing instruments, weighing accuracy. An index facilitates rapid location of the required term. The authors welcome suggestions and corrections at www.mt.com/w eighing-terms. Braunschweig (DE) and Greifensee (CH), The Authors Summer 2009 Foreword Since its founding in 1875, the International Bureau of Weights and Measures (BIPM) has had a unique role in mass metrology. The definition of the kilogram depends on an artefact conserved and used within our laboratories. The mass embodied in this - tefact defines the kilogram, and this information is disseminated throughout the world to promote uniformity of measurements. Although the definition of the kilogram may change in the re- tively near future, reflecting the success of new technologies and new requirements, the task of ensuring world-wide uniformity of mass measurements will remain.

This second edition of Mass Metrology: The Newly Defined Kilogram has been thoroughly revised to reflect the recent redefinition of the kilogram in terms of Planck’s constant. The necessity of defining the kilogram in terms of physical constants was already underscored in the first edition. However, the kilogram can also be defined in terms of Avogadro’s number, using a collection of ions of heavy elements, by the levitation method, or using voltage and watt balances. The book also addresses the concepts of gravitational, inertial and conventional mass, and describes in detail the variation of acceleration due to gravity. Further topics covered in this second edition include: the effect of gravity variations on the reading of electronic balances derived with respect to latitude, altitude and earth topography; the classification of weights by the OIML; and maximum permissible error in different categories of weights prescribed by national and international organizations. The book also discusses group weighing techniques and the use of nanotechnology for the detection of mass differences as small as 10-24 g. Last but not least, readers will find details on the XRCD method for defining the kilogram in terms of Planck’s constant.

The book deals mainly with direct mass determination by means of a conventional balances. It covers the history of the balance from the beginnings in Egypt earlier than 3000 BC to recent developments. All balance types are described with emphasis on scientific balances. Methods of indirect mass determination, which are applied to very light objects like molecules and the basic particles of matter and celestial bodies, are included. As additional guidance, today’s manufacturers are listed and the profile of important companies is reviewed. Several hundred photographs, reproductions and drawings show instruments and their uses. This book includes commercial weighing instruments for merchandise and raw materials in workshops as well as symbolic weighing in the ancient Egyptian’s ceremony of ‘Weighing of the Heart’, the Greek fate balance, the Roman Justitia, Juno Moneta and Middle Ages scenes of the Last Judgement with Jesus or St. Michael and of modern balances. The photographs are selected from the slide-archives of the late Richard Vieweg (1896-1972) (former President of the Physikalisch-Technische Bundesanstalt, Braunschweig, Germany), of the late Hans R. Jenemann (1920-1966) (former head of the Analytical Laboratory of Schott & Gen., Mainz, Germany) and of his wife Irene (1933-2008) and of Erich Robens.