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open access

A Complete Mode Sum for LF, VLF, ELF Terrestrial Radio Wave Fields

Description: Report discussing the VLF, ELF propagation in the earth-ionosphere waveguide emphasizing the total field found by summing all modes which contribute appreciably. Solutions are given and calculations are made for a homogeneous isotropic ionosphere, a homogeneous ionosphere with a constant radial magnetic field imposed, and an ionosphere with a magnetic field of arbitrary dip angle.
Date: October 1, 1964
Creator: Johler, J. Ralph & Berry, Leslie A.
open access

On the Statistical Theory of Electromagnetic Waves in a Fluctuating Medium (II): Mathematical Basis of the Analogies to Quantum Field Theory

Description: Report discussing the relationship between quantum field theory and the the statistical theory of waves. Basic equations exist in the latter theory which correspond closely to the fundamental equations of the former theory; i.e., to the commutation relations and the Heisenberg equation of motion. A probability density function of waves is introduced here which corresponds to the probability amplitude function in quantum mechanics. The theory of the statistical Green's functions and their relati… more
Date: December 7, 1964
Creator: Furutsu, K.
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Refractive Indices and Densities of Aqueous Solutions of Invert Sugar

Description: Report of the refractive indices and densities of aqueous solutions of invert sugar at temperatures of 15, 20, 25, and 30º C, for concentrations up to about 82 percent of invert sugar (by weight). From the results, equations have been derived which relate the refractive index and percent of invert sugar (weight in air) at each temperature. Other equations relate the absolute density and percent of invert sugar (weight in vacuum) at each temperature. Five-decimal tables giving the refractive ind… more
Date: June 7, 1963
Creator: Snyder, Carl F. & Hattenburg, Albert T.
open access

Reduction of Data for Piston Gage Pressure Measurements

Description: Report discussing pressure measurements made with piston gages that are affected by gravity, temperature, pressure, and several other variables. For accurate determinations of pressure the calculations must take these variables into account. A general equation is developed and simplified procedures for calculating pressure are illustrated.
Date: June 17, 1963
Creator: Cross, J. L.
open access

Compilation of the Melting Points of the Metal Oxides

Description: Report compiling the melting points of 70 metal oxides published prior to January 1963. Both the original melting point and the equivalent value based on the International Practical Temperature Scale of 1948 are presented. Included in the survey is information on pertinent experimental details such as the method of temperature measurement, purity, furnace type, and environmental conditions.
Date: October 10, 1963
Creator: Schneider, Samuel J.
open access

Measurement Assurance for Gage Blocks

Description: 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.
Date: February 1979
Creator: Croarkin, Carroll; Beers, John & Tucker, Clyde
open access

Evaluating the Impact of Securities Regulation on Venture Capital Markets

Description: 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."
Date: June 1980
Creator: Barth, James R.; Cordes, Joseph J. & Tassey, Gregory
open access

New Description of Thorium Spectra

Description: Report discussing wavelengths and estimated intensities in electrodeless lamp and spark sources presented for 15121 lines of ThI, ThII, ThIII, and ThIV in the spectral range from 2000 to 11550 A. Also contains tables of previously published interferometric values.
Date: June 21, 1960
Creator: Zalubas, Romuald
open access

Atomic Energy Levels in Crystals

Description: Report discussing discrete energy levels observed within certain crystals which are due to perturbations of energy levels of the free ion by an electrostatic field arising from the crystal lattice. The analytic procedures for determining the field from the charge configuration are given, and the resulting fields are classified according to their symmetry. After a general survey of group-theoretical ideas, the applicable groups are analyzed in detail, and characters appropriate for both integral… more
Date: February 24, 1961
Creator: Prather, John L.
open access

The First Spectrum of Hafnium (HF I)

Description: 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 th… more
Date: July 1976
Creator: Meggers, William F. & Moore, Charlotte E.
open access

The Dynamics of Fields of Higher Spin

Description: 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.
Date: August 1976
Creator: Hayward, Raymond W.
open access

Temperature-Induced Stresses in Solids of Elementary Shape

Description: Report discussing how solids subjected to non-uniform temperature change develop internal stresses determined by, (1) the temperature distribution within the solid, and (2) certain physical constants of the material. For two varieties of heating, the equations determining stress have been put in convenient form for practical use, and tables of certain temperature functions show how to determine stresses in a slab, in a cylinder, or in a sphere subjected to either of two modes of heating. The te… more
Date: June 21, 1960
Creator: Adams, Leason H. & Waxler, Roy M.
open access

A Spectrophotometric Atlas of the Spectrum of CH from 3000A to 5000A

Description: Report of the near ultraviolet and visible emission spectrum of CH presented in the form of a spectrophotometric atlas. The spectrum was recorded photoelectrically from an acetylene-oxygen flame in the region 4900 to 3000 A by use of a high-resolution grating monochromator. Each of the lines in the CH spectrum is identified.
Date: February 14, 1961
Creator: Bass, Arnold M. & Broida, H. P.
open access

Vibration-Rotation Structure in Absorption Bands for the Calibration of Spectrometers From 2 to 16 Microns

Description: Reports discussing bands of common gases that have been tabulated and remeasured wherever necessary from 2 to 16 microns to obtain an accuracy of about 0.03 cm-1 throughout the region and to provide good calibrating points at frequent intervals. Some 600 rotation-vibration lines are illustrated in 20 spectrograms and wavenumbers are listed in companion tables with considerable intercomparison with worthy data obtained in other laboratories. The absorption bands were remeasured or calibrated by … more
Date: June 21, 1960
Creator: Plyler, Earle K.; Danti, Alfred; Blaine, L. R. & Tidwell, E. D.
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Geometrical Considerations and Nomenclature for Reflectance

Description: 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… more
Date: October 1977
Creator: Nicodemus, F. E.; Richmond, J. C.; Hsia, J. J.; Ginsberg, I. W. & Limperis, T.
open access

Analysis of Optically Excited Mercury Molecules

Description: Report presenting new measurement techniques used to obtain potential curves, f-values, and kinetic behavior for Hg2. The Hg2 molecule is representative of a class of molecules which have dissociative ground states and bound excited states. It can therefore be used as a prototype of this class of molecules which are of interest as potential new laser candidates. Because of the non-bound ground state, standard absorption spectroscopic techniques cannot be used to obtain the necessary information… more
Date: January 1975
Creator: Drullinger, R. E.; Hessel, M. M. & Smith, E. W.
open access

The Theory of the Optical Wedge Beam Splitter

Description: Report discussing optical wedge beam splitters and the basic theory for computing the ratio of the intensity of the incident beam to the intensity of any selected emerging beam and also for computing the direction of the emerging beam, assuming that the wedge angle, index of refraction, angle of incidence, and number of reflections are known.
Date: October 1974
Creator: Beers, Yardley
open access

Relativistic Many-Body Bound Systems: Electromagnetic Properties

Description: Report presenting the formulae for the calculation of the electron scattering form factors, and of the static magnetic dipole and electric quadrupole moments, of relativistic many-body bound systems. The framework, given in NBS Monograph 147, is relativistic quantum field theory in the Schrodinger picture ; the physical particles, i.e. the solutions of the interacting fields, are given as linear combinations of the solutions of the free fields, called the parton fields. The parton-photon intera… more
Date: April 1977
Creator: Danos, Michael & Gillet, Vincent
open access

The Role of Standard Reference Materials in Measurement Systems

Description: Report is a guide to Standard Reference Materials (SRM's) and should be useful to all users of SRM's particularly those in countries developing national measurement systems. It is not intended to be an exhaustive description of the NBS-SRM program, but rather a review of the role SRM's play in the measurement system, how SRM's are certified, and what the certification means. To illustrate the use of SRM's, several selected industries are described in which SRM's have made significant contributi… more
Date: January 1975
Creator: Cali, J. P.; Mears, T. W.; Michaelis, R. E.; Reed, W. P.; Seward, R. W.; Stanley, C., L. et al.
open access

Liquid-in-Glass Thermometry

Description: 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 incl… more
Date: January 1976
Creator: Wise, Jacquelyn A.
open access

A Gage Block Measurement Process Using Single Wavelength Interferometry

Description: 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.
Date: December 1975
Creator: Beers, John S.
open access

Properties of Glasses in Some Ternary Systems Containing BaO and SiO2

Description: Report discussing the glass forming regions in six ternary oxide systems containing BaO, Si02, and a third oxide. The properties of the resulting glasses were measured and the results reported. The data on refractive indices, dispersions, and specific volumes were evaluated by computer methods in an attempt to identify "substructures" containing the cations present in the glasses.
Date: September 1973
Creator: Cleek, Given W. & Babcock, C. L.
open access

Graphical Recoupling of Angular Momenta

Description: 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.
Date: October 1973
Creator: Lehman, D. R. & O'Connell, J. S.
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