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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 indices and densities of invert sugar solutions containing 1 to 85 percent of sugar are given for each percentage of invert sugar at the four temperatures.
Date: June 7, 1963
Creator: Snyder, Carl F. & Hattenburg, Albert T.

Causes of Variation in Chemical Analyses and Physical Tests of Portland Cement

Description: Report discussing variations in comparative tests of portland cements that could lead to the rejection of a material fully conforming to specification requirements, or the acceptance of a material with undesirable chemical or physical properties. Many of the causes for variation in chemical analyses and physical test results are listed in this discussion, and remedies for some of the more frequently encountered deficiencies in apparatus and methods are suggested.
Date: April 27, 1961
Creator: Bean, B. Leonard & Dise, John R.

Thermal Expansion of Technical Solids at Low Temperatures: A Compilation From the Literature

Description: Report giving tables of the linear contraction relative to 293 ºK, (L293ºLT)/L293, and the linear expansion coefficient, dL/L293dT, of thirty elements, forty-five alloys, twenty-two other inorganic substances and twenty plastics and elastomers in the temperature range, 0 to 300 ºK.
Date: May 19, 1961
Creator: Corruccini, Robert J. & Gniewek, John J.

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 and half-integral angular momenta of the free ion are tabulated. Text includes tabulations, equations, and matrices using Wigner and Racah coefficients.
Date: February 24, 1961
Creator: Prather, John L.

Corrected Optical Pyrometer Readings

Description: Report presenting a table of corrected optical pyrometer readings which enables optical pyrometer users to convert observed temperature immediately to the true temperature, if the effective emissivity of the material being observed is known. The table gives observed temperatures from 1,000 to 3,000ºK in increments of 5 degrees, from 3,000 to 5,000ºK in increments of 10 degrees, from 5,000 to 10,000ºK in increments of 50 degrees, and from 10,000 to 39,900ºK in increments of 100 degrees. For these, true temperatures are tabulated for 49 emissivities ranging from 0.02 to 0.98 in increments of 0.02.
Date: April 21, 1961
Creator: Poland, D. E.; Green, J. W. & Margrave, J. L.

Bibliography of Temperature Measurement: July 1960 to December 1965

Description: Report combining National Bureau of Standards Monograph 27 with the references given in Supplement 1 (May 13, 1963) and issued as a single publication to assist users of this material. References concern the field of temperature measurement. These references were collected from two general sources: Scientific and technical literature and government reports. References are divided into a number of categories based on the type of instrument used. Some references to calibration of instruments and to scientific theories upon which temperature measurement is based are also presented.
Date: April 28, 1967
Creator: Olsen, Lief O. & Halpern, Carl

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.

Standard X-ray Diffraction Powder Patterns: Section 1. Data for 46 Substances

Description: Report discussing forty-six standard X-ray diffraction powder patterns. Fourteen are to replace twelve patterns already given in the X-ray Powder Data File, and thirty-four are for substances not previously included. The X-ray Powder Data File is a compilation of diffraction patterns from many sources and is used for the identification of unknown crystalline materials by matching spacing and intensity measurements. The patterns were made with a Geiger counter X-ray diffractometer, using samples of high purity.
Date: March 9, 1962
Creator: Swanson, Howard E.; Morris, M. C.; Stinchfield, Roger P. & Evans, Eloise H.

Microwave Impedance Measurements and Standards

Description: Report presenting a survey and discussion of well-known microwave impedance measurement techniques. The discussion includes an introduction which emphasizes basic concepts and reflection coefficient-voltage standing-wave ratio relationships. Sources of error in the various measurement techniques are discussed and methods to reduce errors are presented. Methods using rotating loops and resonance lines are included and a brief discussion of microwave impedance standards is given.
Date: August 12, 1965
Creator: Beatty, Robert W.

A Study of Lunar Surface Radio Communication

Description: Report discussing the problem of point-to-point radio communication on the moon. Equations and curves are presented to estimate power requirements in lunar communication systems. Consideration is given to ground wave attenuation over both layered and non-layered grounds, antenna ground losses in situations where ground screens are impractical, noise level estimates in the receiving system, and the effects on propagation of possible lunar ionospheres. An example of the calculation of required power for a particular communication system is given, and further studies are suggested.
Date: September 14, 1964
Creator: Vogler, L. E.

Curves of Input Impedance Change Due to Ground for Dipole Antennas

Description: Report presenting graphs of the change in input impedance of electrically short dipole antennas in the presence of an isotropic and homogeneous ground which considers four types of antennas: horizontal and vertical, electric and magnetic dipoles. Curves of the change in both the input resistance and reactance are shown for a wide range of values of the frequency, antenna height above the ground, and electromagnetic ground constants.
Date: January 31, 1964
Creator: Vogler, L. E. & Noble, J. L.

The NBS Standard Hygrometer

Description: Report describing a gravimetric hygrometer that serves as the NBS standard instrument for the measurement of the moisture content of gases on an absolute basis in terms of mixing ratio (mass water vapor/ unit mass of dry gas). The National Bureau of Standards and other laboratory reference and working instruments are compared and calibrated with this instrument. The measuring operation involves the absorption of the water vapor from a water vapor-gas mixture by a solid desiccant and the determination of the mass of this water vapor by precision weighing; it also involves the determination of the volume of the associated gas of known density by counting the fillings of two calibrated stainless steel cylinders. The construction and operation of the instrument is described. Discussions of the tests and calibrations of component parts, and of the sources of errors also are included. There is also an analysis of the random and systematic errors effecting the overall accuracy in the determination of mixing ratio.
Date: May 1, 1964
Creator: Wexler, Arnold & Hyland, Richard W.

Colors of Signal Lights: Their Selection, Definition, Measurement, Production, and Use

Description: Report discussing the selection, specifications, and use of signal-light colors. It discusses the nature of the problem, and the mathematical representation, recognition, production, control, and use of such colors. The characteristics of different types of chromaticity boundaries and the purpose and effect of the requirement for similarity of chromaticity characteristics are given special consideration. The treatment is varied according to the intended use. The discussion of the control of colors and the section on the use of colors are nontechnical, whereas the section on the production of signal colors is designed for the colorimetrist who is faced with the problem of selecting limit filters or drafting a specification.
Date: April 3, 1967
Creator: Breckenridge, F. C.

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.

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 relationships to the expectation values of the physical variables is also extensively developed. It is found that there exists a one-to-one correspondence between the formalism of Green's functions presented here and that used in field theory.
Date: December 7, 1964
Creator: Furutsu, K.

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.

NBS Viscometer Calibrating Liquids and Capillary Tube Viscometers

Description: Report discussing measurements of viscosity made with relative viscometers. These instruments must be calibrated with liquids whose viscosities are known. NBS provides a series of 10 oils for this purpose. Their viscosities range from 0.02 to 450 poises and their temperature coefficients of viscosity range from 2.1 to 9.4 percent per degree C. The less viscous oils are more stable. Correction formulas for errors or conditions are presented.
Date: December 26, 1962
Creator: Hardy, R. C.

Systems of Electrical Units

Description: Report describing the various systems of measurement used in the literature on electricity and magnetism, with respect to their units. Their historical development is summarized. The manner in which each is derived from either of the two alternative points of view of the experimentalist and the theoretician is compared and contrasted. Tables are included for the conversion of equations and numerical values from one system to another.
Date: September 20, 1962
Creator: Silsbee, Francis B.

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.

Shielding Against Gamma Rays, Neutrons, and Electrons From Nuclear Weapons: A Review and Bibliography

Description: Report discussing the problem of predicting dose rates and of estimating the effectiveness of shielding from radiations resulting from nuclear explosions. A number of calculations and supporting experiments regarding the penetration and diffusion of gamma rays, neutrons, and electrons through air and bulk materials are summarized. Indications are given of gaps in such input information. A selection of 485 references from the unclassified literature is presented, of which 388 are cataloged as to source geometry and energy, absorber material and configuration, type of data presented, and method of calculation or experimental technique. These cataloged references include radiation field studies ranging from the point-source infinite-medium situation up through such complicated geometries as foxholes, shelters, and conventional structures. The other references are of a general or review nature or contain input spectral data.
Date: February 24, 1964
Creator: Hubbell, J. H. & Spencer, L. V.

Radio Meteorology

Description: Report compiling the work done in radio meteorology over the past ten years at the National Bureau of Standards' Central Radio Propagation Laboratory (CRPL). There is an emphasis upon the effects of the lower atmosphere on the propagation of radio waves. The CRPL group has concentrated upon the refraction of radio waves as well as the refractive index structure of the lower atmosphere on both synoptic and climatic scales. Additional chapters on radio-meteorological parameters and the absorption of radio waves by the various constituents of the lower atmosphere.
Date: March 1, 1966
Creator: Bean, B. R. & Dutton, E. J.

Microwave Attenuation Standards and Measurements

Description: Report discussing microwave attenuation measurement methods and standards. In addition, a relatively new and more precise way of representing and analyzing an attenuation measurement is presented. This in turn permits more rigorous definitions and error analyses than were previously possible. The referral of microwave attenuation measurements to standards operating at lower frequencies is discussed with particular attention to the errors in the referral processes as well as the errors in the standards themselves. Desirable characteristics are listed for attenuators which are suitable for calibration. Measurement methods are classified and described. Comments are made on the accuracy and convenience of various methods, and references are given which cover most of the basic and important research in this field. Key words: Microwave, attenuation, measurements, standards, tutorial.
Date: April 3, 1967
Creator: Beatty, Robert W.

Abscissas and Weights for Guassian Quadrature For N=2 to 100, and N-125, 150, 175, 200

Description: The abscissas and weights for Gaussian Quadrature of order N = 2 to 100,and N = 125, 150, 175, and 200 are given. The abscissas are given to twenty-four places and the error is estimated to be no more than 1 unit in the last place. The weights are given to twenty-three places and the error is estimated to be no more than 1 unit in the last place.
Date: December 28, 1966
Creator: Love, Carl H.

Oxidation of Polycyclic, Aromatic, Hydrocarbons: A Review of the Literature

Description: Report discussing the literature on the oxidation of polycyclic, aromatic hydrocarbons. Information has been assembled on (1) the oxidants effective in the oxidation of such hydrocarbons, (2) the relative reactivity of the hydrocarbons, (3) the conditions under which oxidation proceeds, (4) the chemical mechanisms involved when such oxidations occur, and (5) the products formed.
Date: September 17, 1965
Creator: Tipson, R. Stuart