Abstract: This publication collects and summarizes the specialized information needed to operate the ac-dc difference laboratory and calibration service at NIST (Gaithersburg). It also serves as a convenient reference source for the users of this calibration service and other interested people by documenting the service and its underlying background in considerable detail. It contains the following: an annotated table of contents, a topical index, and a glossary of common ac-dc acronyms; an overview of the service; selected published papers; instructions for the operation of the comparator systems; a schedule for the recalibration and periodic checks of the NIST thermal converters; and a sample report of calibration.

Abstract: The NIST calibration service for standard masses is described. Weights which are accepted for calibration range in nominal values from 1 mg to 13,600 kg (30,000 pounds). We also accept weights used to generate standard pressures in piston gages. Cleaning procedures used on weights prior to calibration are described. The measurement algorithms (including density determinations of single-piece kilogram weights) and the uncertainties assigned to calibrated weights are discussed. We also describe the system now in place to monitor the quality of calibrations. Finally, we assess the limitations of the present controls on measurement quality and outline improvements which are underway.

Abstract: The National Institute of Standards and Technology's Standard Reference Data Program manages a network of data centers that prepare evaluated databases of physical and chemical properties of substances. Databases are available in printed form, on magnetic tapes, diskettes, and through on-line computer networks. This document provides a comprehensive list of the products available from the National Standard Reference Data System (NSRDS) for the years 1987-1989, including indexes qualified by author, material, and property terms. Ordering information and current prices can be found at the end of this document.

From page 2: The National Institute of Standards and Technology research reactor is a national center for the application of reactor radiation to a variety of problems of national concern. Major program areas at the reactor include the application of neutron scattering methods to research in materials science, trace analysis by neutron activation, nondestructive evaluation (via neutron radiography and scattering), neutron standards and dosimetry , and isotope production and radiation effects.