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Chemistry of Cement: Proceedings of the Fourth International Symposium, Volume 1, 1960

Description: Document containing principle and supplementary papers presented at the Fourth International Symposium on the Chemistry of Cement, as well as discussions of those papers by members of the Symposium. Index begins on page 551.
Date: August 31, 1962
Creator: United States. National Bureau of Standards.
Partner: UNT Libraries Government Documents Department

Systems of Electrical Units

Description: Report issued by the U.S. National Bureau of Standards discussing different systems of electrical units. As stated in the introduction, "the various systems of measurement, with their respective sets of units, used in the literature on electricity and magnetism are described in detail" (p. 1). This report includes tables.
Date: August 1963
Creator: Silsbee, Francis B.
Partner: UNT Libraries Government Documents Department

Reduction of Data for Piston Gage Pressure Measurements

Description: Report issued by the U.S. National Bureau of Standards discussing piston gage pressure and reducing errors of measurement. Sources of error are described and evaluated in order to "reduce the magnitude of overall error of measurement" (p. 1). This report includes tables, and illustrations.
Date: June 17, 1963
Creator: Cross, J. L.
Partner: UNT Libraries Government Documents Department

Bibliography on Molecular and Crystal Structure Models

Description: Report that briefly describes many of the models of crystal and molecular structures which have appeared in the literature, and presents a bibliography of the publications, grouped according to model types, which describe the models in more detail.
Date: May 20, 1960
Creator: Smith, Deane K.
Partner: UNT Libraries Government Documents Department

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 using either a precisely graduated grating circle or standard atomic lines with the fringe system formed by a Fabry-Perot interferometer. Characteristic features of the individual bands are discussed briefly and references to other publications are given. The substances used for calibration include H2O, CO2, CO, HCl, HBr, NH3, C2H2, CH4, N2O, and polystyrene film.
Date: June 21, 1960
Creator: Plyler, Earle K.; Danti, Alfred; Blaine, L. R. & Tidwell, E. D.
Partner: UNT Libraries Government Documents Department

Effects of Finite Lattice Heat Capacity on Spin Lattice Relaxation: Theory and Numerical Analysis

Description: 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.
Date: August 1, 1967
Creator: Peterson, Robert L.
Partner: UNT Libraries Government Documents Department

Oscillator Strengths and Transition Probabilities fro 3288 Lines of Fe I

Description: Report of a homogeneous set of intensity-related data calculated for 3288 spectral lines of Fe I in the region from 2100 to 9900 angstroms. The quantities tabulated in the present monograph include log (g__), log (gf), gf,f,gA, and A. Since recent investigations do not support excitations corrections in the case of Fe I and certain other spectra, the present tabulation incorporates a removal of that normalization function. This recalculation affects the values for all lines whose upper energy levels lie above 46000 cm -1 and should significantly improve the internal consistency of the present data.
Date: March 1968
Creator: Corliss, C. H. & Tech, J. L
Partner: UNT Libraries Government Documents Department

Infrared Spectroscopy of Carbohydrates: A Review of the Literature

Description: 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.
Date: June 1968
Creator: Tipson, R. Stuart
Partner: UNT Libraries Government Documents Department

An Introduction to the Description and Evaluation of Microwave Systems Using Terminal Invariant Parameters

Description: 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.
Date: October 1969
Creator: Engren, Glenn F.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 2. Data for 37 Substances

Description: Report discussing standard X-ray diffraction powder patterns for thirty-seven substances. Eleven are to replace patterns already given in the X-ray Powder Data File issued by the American Society for Testing and Materials, and twenty-six patterns indicated by asterisks 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: May 3, 1963
Creator: Swanson, Howard E.; Morris, M. C.; Stinchfield, Roger P. & Evans, Eloise H.
Partner: UNT Libraries Government Documents Department

Influence of a Sector Ground Screen on the Field of a Vertical Antenna

Description: 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.
Date: April 15, 1963
Creator: Wait, James R. & Walters, Lillie C.
Partner: UNT Libraries Government Documents Department

Tensile and Impact Properties of Selected Materials From 20 to 300 ºK

Description: Report giving the tensile and impact properties of structural materials that were experimentally determined at temperatures from 20 to 300 ºK. Tensile properties of a few materials were also determined at 4 ºK. The properties experimentally determined were the yield strength, tensile strength, elongation, and reduction of area, the stress versus strain curve, and the impact energy. The test equipment and procedures are described. The individual data are presented in tables, and the average results are displayed in graphs.
Date: June 28, 1963
Creator: Warren, K. A. & Reed, R. P.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department

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.
Partner: UNT Libraries Government Documents Department