Report presenting a relativistic theory of motion that is free of many of the difficulties common in relativistic equations of motion. This Lagrangian theory describes fields and particles with arbitrary mass and charge and having any discrete spin, integer or half integer.

From Abstract: "This work traces the development of the Loran-C concept from its inception as a 100-kHz pulse hyperbolic navigation system to more recent times when it found a variety of applications to both timing and navigation."

Report describing procedures for making quantum mechanical calculations of rotational energy levels and rotational line intensities in diatomic molecules. The procedures are illustrated by sample calculations. A familiarity with the material of this report should enable a practicing electronic spectroscropist to carry out, though in a rather mechanical way, his own theoretical calculations for molecules under experimental investigation.

Book presenting an introduction to time, timekeeping, and the uses of time information, especially in the scientific and technical areas. Serves as introductory text for laymen.

Scope of the Guide: "This guide is not all-inclusive of the subject of impedance measurement and the reader should understand at the outset what he can or cannot expect to find. To help in establishing the bounds of subject matter included, consider the ideal impedance-measuring instrument as having the following the characteristics and capabilities: (1) unrestricted frequency range (2) unrestricted impedance range (3) unrestricted capabilities with respect to bias, ambience, applied power, etc. (4) error free (5) performs measurements instantaneously (6) zero acquisition cost (7) zero operating cost."

From Abstract: "This paper presents a comprehensive report on the measurement and the use of rotary-vane attenuator as an interlaboratory standard."

Report presenting a diagrammatic method for solving angular momentum recoupling problems. It is shown that a few graphical elements with a set of rules for their use lead to the solution of many types of recoupling problems in an intuitive and systematic way. Several examples are given together with exercises to develop the reader's facility with the method.

Report documenting standard x-ray diffraction powder patterns for various compounds, intended to replace previous data or provide information for new substances. It describes the methods and, for each substance, outlines any previous data as well as information about the sample used and structural data, with a table of diffraction patterns.

Report continuing W. K. Meggers' previous analysis in LS-coupling. This coupling is not rigorous in Hf I, and many intervals are irregular. Consequently, the levels are given also in numerical order with the even and odd levels presented in separate tables. The long line lists are given in two Appendices: Appendix A contains the observed Zeeman data for the individual lines, 531 in all; Appendix B consists of the complete line list of observed and classified lines. By far the greater part of the analysis is that of Meggers.

From Abstract: "Comparisons with other other intensity measurements in individual spectra indicate that the National Bureau of Standards spectral-line intensities may have average errors of 20 percent, but first of all they provide uniform quantitative values for the seventy chemical elements commonly determined by spectrochemists. These data are presented by element in part I, and all 39000 observed lines are given in order of wavelength in part II."

From Preface: "This new edition of the NBS Tables of Spectral-Line Intensities incorporates three improvements on the original edition of 1961. In the original edition only about 25 000 of the 39 000 lines in the tables had been classified. In the ensuing thirteen years, about 8500 more lines (chiefly rare-earths) have been classified and the new classifications are here incorporated."

From Introduction: "The first part of this monograph is concerned with the analysis of closed region wave-guide junction problems. This allows simplification of the techniques to be used since no branch cuts are involved in the spectral representation of the fields. However, the analysis can be extended to open region problems in a logical manner. This is the subject of the second part of this monograph."

Report documenting standard x-ray diffraction powder patterns for various compounds, intended to replace previous data or provide information for new substances. It describes the methods and, for each substance, outlines any previous data as well as information about the sample used and structural data, with a table of diffraction patterns.

Report documenting standard x-ray diffraction powder patterns for various compounds, intended to replace previous data or provide information for new substances. It describes the methods and, for each substance, outlines any previous data as well as information about the sample used and structural data, with a table of diffraction patterns.

Report documenting standard x-ray diffraction powder patterns for various compounds, intended to replace previous data or provide information for new substances. It describes the methods and, for each substance, outlines any previous data as well as information about the sample used and structural data, with a table of diffraction patterns.

Report documenting standard x-ray diffraction powder patterns for various compounds, intended to replace previous data or provide information for new substances. It describes the methods and, for each substance, outlines any previous data as well as information about the sample used and structural data, with a table of diffraction patterns.

Report issued by the U.S. National Bureau of Standards discussing specifications of reflectance and proposed nomenclature. As stated in the introduction, "this monograph presents a unified approach to the specification of reflectance in relation to the beam geometry of both the incident and the reflected flux in any reflectometer or in any application of measured reflectance data" (p. 1). This report includes illustrations.

Report presenting a unified approach to the specification of reflectance, in terms of both incident- and reflected- beam geometry. Nomenclature to facilitate this approach is proposed. Nomenclature for categorizing and specifying reflectance quantities for a variety of different beam configurations (both incident and reflected beams) is described, and all are defined and interrelated in terms of the bidirectional reflectance-distribution function. The conditions under which the formalism can be applied, including situations involving considerable sub-surface scattering, are carefully established. The entire treatment is limited to the domain of classical geometrical-optics radiometry and does not take into account interference and diffraction phenomena, such as are frequently encountered with highly coherent radiant flux.

Report discussing the different bases for determining mass values and instances where these differences may be crucial. The first part is a historical summary of weighing, standards, and the assignment of value; and the interfacing of mass measurements with civilization. The second part discusses in detail the methods of assigning mass values. Ways to convert from values on one basis to values on another basis are discussed.

From Abstract and Introduction: "This paper is, in essence, a report on the extension of the techniques first suggested in NBS Monograph 103 "Realistic Uncertainties and the Mass Measurement Process" to the area of length measurement. This paper covers the progress to date on the long gage blocks (from 5 to 20 in the length). The purpose of this purpose is to verify the closure between the "old" process and the "new" process, and to describe the present "points of departure" upon which some of the current assigned length values are based."

Report presenting tables as a supplement to those given in NBS Monograph 125. Tables were calculated from the power series expansions presented in that Monograph. They are based upon the absolute electrical units and the International Practical Temperature Scale of 1968 (IPTS-68). Reference tables for several thermoelements versus platinum (Pt-67) are given with values of the thermoelectric voltage as a function of temperature in degrees Fahrenheit. Only tables for standard letter-designated thermoelements are included.

From Abstract: "Revised reference data for thermocouples have been generated in a cooperative program between groups of the National Bureau of Standards in Boulder and Gaithersburg.This Monograph contains tables, analytic expressions, various approximations, and explanatory text.

From Introduction: "This monograph describes the calibration of standard platinum resistance thermometers at the NBS including the equipment, techniques, and procedures."

From Abstract: "This compilation abstracts original experimental data on the mechanical, thermal, and electrical properties of six commercially available polymers. The data are also summarized and a brief description of each polymer is included."