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- The Development of Loran-C Navigation and Timing
- 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."
- The Divergent Beam (Kossel) X-Ray Method and Its Uses in Measuring Strain Contours in an Individual Grain of Fe-3 Weight Percent Si Transformer Sheet
- From Abstract: "The results showed that a variable strain distribution existed in the alloy sheet at the time it was ready for insertion into a transformer core. Small applied comprehensive and tensile loads tended to rearrange this variable strain distribution but not appreciably alter the total stored elastic energy."
- The Dynamics of Fields of Higher Spin
- 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.
- Effect of Exposure Site on Weather Resistance of Porcelain Enamels Exposed for Three Years
- From Introduction: "The present report describes the condition of all of the porcelain enamels after exposure for 3 yr."
- Effect of Mortar Properties on Strength of Masonry
- Report issued by the National Bureau of Standards over studies conducted on the effects of mortar on the strength of masonry. Materials, methods, and results are presented and discussed. This report includes tables, illustrations, and photographs.
- The Effect of Time Ordering on the Lyman α Profile
- Report investigating the effects of time-ordering over the complete line profile using a unified theory of spectral line broadening previously developed. The behavior of the time-ordered thermal average and un-time-ordered thermal average are compared. The Fourier transform of the thermal average is obtained analytically. Calculations for the line profile of the Lyman-[functional symbol alpha] line of hydrogen are presented and are representative in that the full thermal average is replaced by the thermal average with the electron velocity distribution approximated by f(v)=[functional symbol alpha] (v-vav) where vav is the thermal velocity for the plasma in question.
- Effects of Finite Lattice Heat Capacity on Spin Lattice Relaxation: Theory and Numerical Analysis
- Report discussing the transient magnetic behavior of a paramagnetic substance, after an initial disturbance, considered theoretically for a variety of situations in which the lattice temperature rises as a result of energy flow from the magnetic (electron spin) system. Next, the opposite extreme is considered - that in which the resonant and remaining modes are totally uncoupled. Finally, there is a consideration of the case of spins coupled only to the resonant phonons, which in turn are coupled to a constant temperature bath, whether this be the helium or the remaining modes.
- Effects of Thermal Shrinkage on Built-up Roofing
- From Introduction: "The object of this research was to identify and study some of the factors involved in premature failures and to relate the pertinent factors to roof performance."
- Electrical Parameters of Precision, Coaxial, Air-dielectric Transmission Lines
- From Introduction: "Following the guidelines established by this committee, several commercially developed precision connectors have appeared on the market which have led to the wide use of the precision coaxial lines as immittance standards. This paper has been prepared to alleviate this situation by providing graphs from which the electrical parameters of the lines may be determined rapidly and accurately."
- Electromagnetic Boundary-Value Problems Based Upon a Modification of Residue Calculus and Function Theoretic Techniques
- 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."
- Electron Optical Studies of Low-Pressure Gases
- From Abstract: "This document is the final report of research carried on in the Electron Physics Section of the National Bureau of Standards during the period from February 1, 1955 to March 1962 in developing an electron optical method for the visualization of low-pressure gas flow."
- Energy Dissipation by Fast Electrons
- Report discussing the energy dissipated by fast electrons at different distances from monoenergetic electron sources, for plane perpendicular and point isotropic sources including tabulations and a summary of the theoretical methods and data utilized, and a table of spatial moments.
- An Engineering Method for Calculating Protection Afforded by Structures Against Fallout Radiation
- From Introduction: "The purpose of the paper is to discuss the assumptions and the reasoning by which the calculations described in the Engineering Manual were derived from the data in [1]. The relevant curves from [1] are given in Appendix A and the technical charts from the Engineering Manual are given in appendix B."
- Evaluating the Impact of Securities Regulation on Venture Capital Markets
- Report providing a detailed and analytical assessment of the economic techniques used by researchers to evaluate the efficiency of capital markets. The application of these techniques to that portion of the capital market which supplies venture funds to small, technology-based firms is emphasized. The primary elements of such analysis are the "efficient market ' hypothesis" and the "capital asset pricing model." The empirical analogue of the latter is commonly referred to as the market model."
- An Experimental Study of Phase Variations in Line-of-Sight Microwave Transmissions
- From Introduction: "The purpose of this report is to present an analysis of time variations in: (1) the phase (relative to a stable phase reference) if a 9414 Mc/s signal transmitted over this path, referred to hereafter as single-path phase data; (2) the phase observed at one receiving antenna relative to that observed at an adjacent antenna, referred to as phase difference data; (3) atmospheric refractivity as recorded by a microwave refractometer located at the Haleakala terminal; (4) the wind velocity at both ends of the path, and (5) surface atmospheric refractivity measured at 5 stations located on or near the path."
- Experimental Transition Probabilities for Spectral Lines of Seventy Elements: Derived from the NBS Tables of Spectral-line Intensities
- From introduction: "The goal of the work was to provide lists of the principal lines of the elements generally observed under ordinary conditions in arc spectra, together with their relative intensities on a true scale of relative energy."
- Fire Tests of Precast Cellular Concrete Floors and Roofs
- From Abstract: "The results of an investigation of lightweight, precast cellular concrete planks are given. Fire tests were made of two floor and five roof specimens made up of these planks. Variables, included density of the cellular concrete, thickness and span of the planks, reinforcement, and cover for the latter."
- The First Spectrum of Hafnium (HF I)
- 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 Sundials to Atomic Clocks: Understanding Time and Frequency
- 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.
- A Gage Block Measurement Process Using Single Wavelength Interferometry
- Report describing the interferometric measurement process using a laser light source and a Kosters type gage block interferometer. Continuous evaluation and refinement of the process is aided by statistical treatment and control chart techniques. All error sources, both random and systematic, are evaluated and the process is maintained in a state of statistical control.
- Geometrical Considerations and Nomenclature for Reflectance
- 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.
- Geometrical Considerations and Nomenclature for Reflectance
- 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.
- Graphical Recoupling of Angular Momenta
- 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.
- Hearing Aids
- From Abstract: "This publication contains information, useful to the hard of hearing, on several topics relating to hearing and hearing aids. This publication represents an extensive revision of NBS Circular 534, Hearing Aids. It includes new material based upon research conducted at the National Bureau of Standards during the intervening years."
- Heat Treatment and Properties of Iron and Steel
- From Abstract: "This Monograph has been prepared to give an understanding of heat treatment principally to those unacquainted with this subject. This Monograph has been prepared to answer such inquiries and to give in simplified form a working knowledge of the basic theoretical and practical principles involved in the heat treatment of iron and steel."
- Heat Treatment and Properties of Iron and Steel
- From Abstract: "This Monograph is a revision of the previous NBS Monograph 18. Its purpose is to provide an understanding of the heat treatment of iron and steels, principally to those unacquainted with this subject. The basic principles involved in the heat treatment of these materials are presented in simple form." From Introduction: "This Monograph has been prepared to answer such inquires and to give in simplified form a working knowledge of the basic theoretical and practical principles involved in the heat treatment of iron and steel."
- A High-Dispersion Spectral Analysis of the Ba II Star HD 204075 (ζ Capricorni)
- Report discussing a double differential curve of growth analysis for the Ba II star S Capricorni. Both the sun and � Virginis (G9 II-III) were used as comparison stars. The observational material consists of equivalent widths, central depths, and half-widths for 1100 spectral lines measured on direct-intensity tracings of plates obtained by J. L. Greenstein at the coude focus of the 200-in telescope. The plates cover the spectral regions 3880-4825 A and 5100-6720 A at reciprocal dispersions of 2.3 and 3.4 A/mm, respectively. Atmospheric abundances have been derived for 37 elements.
- Hydrogen Stark Broadening Calculations With the Unified Classical Path Theory
- Report discussing the case of upper and lower state interaction introduced by a unified theory using a more compact tetradic notation. The general result is then applied to the Stark broadening of hydrogen. The thermal average of the time development operator for upper and lower state interaction is presented. A simple technique for evaluating the Fourier transform of the thermal average has been developed. The final calculations based on the unified theory and on the one-electron theory are compared with measurements in the high and low electron density regime.
- Ideal Gas Thermodynamic Functions and Isotope Exchange Functions for the Diatomic Hydrides, Deuterides, and Tritides
- From Abstract: "This Monograph contains a consistent set of tables of thermodynamic properties of a large number of diatomic hydrides, deuterides, and tritides, for the ideal gas state at one atmosphere pressure. In addition to the thermodynamic properties of the molecular gases, the tables also include thermodynamic properties for chemical reactions involving the isotopic exchange of hydrogen."
- Influence of a Sector Ground Screen on the Field of a Vertical Antenna
- Report show the field of a short vertical antenna on a homogeneous ground is modified by the presence of a metallic screen. The screen is taken in the form of a circular disk and a concentric sector. The modification of the field is expressed in the form of surface integrals over the disk and the sector. Extensive numerical results for these basic integrals are given and a number of applications are illustrated.
- Infrared Spectroscopy of Carbohydrates: A Review of the Literature
- Report presenting of survey of the literature on the infrared spectroscopy of carbohydrates in order to assemble and systematize information in this field. Discusses principles and instrumentation, sampling techniques, comparison of samples, and the interpretation of the spectra. In addition, examples are discussed of the use of infrared spectra for qualitative and quantitative purposes and in the determination of structure. Special techniques are briefly described.
- An Institutional Plan for Developing National Standards: With Special Reference to Environment, Safety, and Health
- From Abstract: "This plan was commissioned to provide a framework for the development of all essential non-nuclear energy-related, environmental, safety, and health (ES&H) standards for the private sector to coincide with the commercialization of energy technologies."
- Interactions of High Energy Particles With Nuclei
- Report discussing elastic scattering and diffractive production processes induced in nuclear targets by high energy projectiles. Special attention is paid to the interaction of high energy hadrons and photons. The common features of all these processes are emphasized throughout the article: The multiple scattering and shadowing processes inside of the target nuclei. An effort is made to develop a unified way of treating nuclear interactions of particles which are either hadrons or exhibit some hadronic components in such interactions.
- International Practical Temperature Scale of 1948: Text Revision of 1960
- Report is a text revision of the International Temperature Scale of 1948; the numerical values of temperatures remain the same. The adjective "Practical" was added to the name by the International Committee on Weights and Measures. The scale continues to be based upon six fixed and reproducible equilibrium temperatures to which values have been assigned, and upon the same interpolation formulas relating temperatures to the indications of specified measuring instruments. Some changes have been made in the text to make the scale more reproducible than its predecessor. The triple point of water, with the value 0.01 ºC replaces the former ice point as a defining fixed point of the scale. It is also recommended that the zinc point, with the value 419.505 ºC, be used instead of the sulfur point. The recommendations include new information that has become available since 1948.
- An Introduction to the Description and Evaluation of Microwave Systems Using Terminal Invariant Parameters
- Report presenting the technical background and basis for a new method of evaluating certain performance parameters which are common to all microwave systems. A unique feature of the new measurement concept is its elimination of the precision waveguide and connector requirements for an important class of measurement problems.
- Investigation of the Exploding Wire Process as a Source for High Temperature Studies
- From Introduction: "It is the purpose of this monograph to bring together and report the results of numerous exploding wire experiments performed at the National Bureau of Standards over the past five years."
- Investigation of the Hydraulics of Horizontal Drains in Plumbing Systems
- From introduction: "In this paper, data obtained by Hunter and by the author are reported from laboratory investigations of (1) surge flow introduced into empty simply drains, (2) attenuation of surges in simple drains, (3) continuous full-section flow in simple drains under substantially steady, uniform conditions, (4) steady flow in compound drains, and (5) surge flow introduced through a branch drain into the side or top of a main drain carrying steady flow."
- Ionospheric Radio Propagation
- From Preface: "The purpose of this book is to replace, in part, a previous publication of the National Bureau of Standards (Circular 462) with the same title. The scope of the present work has therefore been broadened to include aspects of ionospheric radio propagation which were not treated in earlier publication."
- Line Parameters and Computed Spectra for Water Vapor Bands at 2.7 mu
- From Foreword: "This Monograph is one of a series intended to provide fundamental information required for the estimation and interpretation of atmospheric transmittance at infrared frequencies. Part I of this Monograph presents the fundamental properties of the 2.7m water vapor band in terms of line absorptions and the integrated transmittance at any frequency for infinite resolution. Part II presents examples of the "degraded" transmittance for finite resolution, as a function of the spectral slit width, concentration, and pressure with which direct observations may be compared."
- Liquid-in-Glass Thermometry
- Report containing information of general interest to manufacturers and users of liquid-in-glass thermometers. This report supersedes Monograph 90. Instructions explaining how to submit a thermometer to the National Bureau of Standards for calibration are provided, and the techniques and equipment, such as stirred liquid comparison baths, used in the calibration procedures are described. A discussion of important principles of acceptable thermometer design and factors affecting their use is included. Listed are tables of tolerances reflecting good manufacturing practices and reasonably attainable accuracies expected with liquid-in-glass thermometers. The calculation of corrections for the temperature of the emergent stem is given in detail for various types of thermometers and conditions of use.
- Low Temperature Mechanical Properties Of Copper and Selected Copper Alloys: A Compilation From the Literature
- From Abstract: "In the past 60 years considerable data have been accumulated concerning the mechanical properties of copper and its alloys.It was felt that there was great need to adequately document these results in one publication. Therefore a unique type of compilation is presented. The compilation is divided into four parts. The first section is intended for quick reference use for those who are interested in average values. The second section includes data from most of the investigators who have published results on the mechanical properties of copper and its alloys. The third section is composed of tables classifying the investigations which were not in section two. The fourth section section lists, in alphabetical order, all references used."
- Mass and Mass Values
- 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.
- Measurement Assurance for Gage Blocks
- Report discussing the philosophy of measurement assurance and the three levels of measurement assurance programs. The measurement assurance programs are outlined to show how control over the measurement process can be maintained and how the offset (or systematic error) from the unit of length maintained by the National Bureau of Standards ban be made negligible. This monograph is intended for those who need to know on a continuing basis the uncertainty of their gage block calibration procedure.
- Measurement Assurance Program - A Case Study: Length Measurements. Part 1. Long Gage Blocks (5 in to 20 in)
- 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."
- The Measurement of Lumped Parameter Impedance: A Metrology Guide
- 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."
- The Measurement of Noise Performance Factors: A Metrology Guide
- From Introduction: "The purpose of this guide is to describe, discuss, and analyze methods of measuring the average noise factor and average effective input noise temperature of an electronic transducer."
- Mechanical Behavior of Crystalline Solids: Proceedings of a Symposium, April 28-29, 1962
- From Introduction: "These first three chapters from a background of introduction and general ideas about dislocations. The next two chapters are concerned specifically with properties of ceramic materials, with emphasis on single crystals."
- Mechanical Properties of Structural Materials at Low Temperatures: A Compilation From the Literature
- From Introduction: "The data are presented with the idea that an engineer who is making initial calculations on equipment for operation at cryogenic temperatures is more interested in obtaining quickly a definite figure that he in evaluating the experimental data given in several detailed reports on the same material. The graphs and tables presented here, consequently, represent an attempt by the authors to perform evaluation of data which have appeared in the literature and to present the design engineer with the result."
- The Mechanics of Pneumatic Tires
- From Abstract: "This treatise is an attempt to provide a rational descriptive and analytical basis for tire mechanics. Chapters of this book are contributed by active research workers in the fields of rubber and textile properties, friction, material properties, tire stress problems, tire design and construction, vehicle skid and handling, and tire mechanical properties."
- Mercury Barometers and Manometers
- From Abstract: "Sources of error in measuring pressures are described in considerable detail, particularly for portable instruments including scale, temperature , gravity, capillarity, vacuum errors and return gas column. Methods of minimizing those errors and of making the corrections, including extensive tables, are presented."