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Nomograms for Obtaining the Compound Composition of Hydrated Limes from the Oxide Analysis

Description: Report with two nomograms presented for rapidly obtaining the compound composition of hydrated limes from the oxide analysis. The general nomogram can be applied to any commercial hydrated lime and gives values accurate to within 0.3 percent while the special nomogram is applicable only to regularly hydrated and highly hydrated dolomitic limes and is accurate to within 0.1 percent.
Date: December 30, 1949
Creator: Levin, Ernest M.
open access

Charts of Compressibility Factors and Charts Showing Quantities Delivered by Commercial Cylinders for Hydrogen, Nitrogen, and Oxygen

Description: Two charts are given for each of the gases hydrogen, nitrogen, and oxygen. The first gives directly the number of standard cubic feet of the gas which a cylinder will deliver. The second chart gives values of the compressibility factor and of the density.
Date: November 17, 1948
Creator: Hoge, Harold J.; Meyers, Cyril H. & McCoskey, Robert E.
open access

Safety for the Household

Description: Introduction: The purpose of this circular is (a) to emphasize the seriousness of certain risks to life and property frequently occurring in or about the home, (b) to give simple methods of care and caution against such hazards, and (c) to stimulate interest in public measures directed toward safety for household and community.
Date: January 12, 1948
Creator: Owen, S. J.
open access

Input Impedance of a Probe Antenna Exciting a TEM Cell

Description: Abstract: The input impedance of a probe antenna exciting a transverse electromagnetic (TEM) transmission line cell is formulated by a variational approach. The formulation also utilizes the results from a previous work on the field distribution inside a TEM cell excited by a vertical electrical Hertzian dipole. The final result of imoedance is shown to consist of two distinct terms, which are respectively contributed by the ordinary rectangular waveguide and the gap perturbation. Numerical res… more
Date: April 1982
Creator: Wilson, Perry F.; Chang, David C. & Ma, Mark T.
open access

Picosecond Time Difference Measurements Utilizing CAMAC-Based ANSI/IEEE-488 Data Acquisition Hardware : Operating Manual IE3, Version 1.0

Description: Abstract: Automated time-difference measurements at the picosecond level have been achieved. The system described combines the best properties of three common methods: the single heterodyne measurement technique, the frequency divider, and the dual-mixer time-difference measurement system. This particular system combines two instrumentation standards, ANSI/IFEE-583 and ANSI/IEEE-488 with new, modular dual-mixer time-difference measurement hardware. The modular, standardized hardware together wi… more
Date: August 1983
Creator: Glaze, D. J. & Stein, S. R.
open access

An Electric and Magnetic Field Sensor for Simultaneous Electromagnetic Near-Field Measurements -- Theory

Description: Abstract: This paper describes the theory of a single sensor to perform simultaneous electric and magnetic near-field measurements. The theory indicates that it is possible to obtain the magnetic-loop and electric-dipole currents using a loop terminated with identical loads at diametrically opposite points. The theory also indicates that it is possible to obtain an ideal load impedance for achieving equal electric and magnetic field responses of the loop. Preliminary experiments have been perfo… more
Date: April 1983
Creator: Kanda, Motohisa
open access

The Characteristics of Iris-Fed Millimeterwave Rectangular Microstrip Patch Antennas

Description: From introduction: The fabrication of various iris-fed millimeterwave rectangular microstrip patch antennas is described. A model is proposed to describe the iris-fed antenna. Irises ranging in size from 15 percent of the area of the patch to the fully open waveguide are used to couple energy into the antenna. Resonance of the antenna is observed to be insensitive to the size of the iris for irises up to 115 percent of the size of the patch. A study is also made of th? relationship of coupling … more
Date: October 1983
Creator: Greenlee, D. H.; Kanda, Motohisa & Chang, David C.
open access

Optical Time-Domain Reflectometer Performance and Calibration Studies

Description: from Introduction: The measurement accuracy of the optical time-domain reflectometer (OTDR) is restricted in some applications by a limited operational dynamic range and by a lack of standardized test procedures. In an effort to better understand these restrictions, we have measured the range of linearity of some avalanche photodiodes used as backscatter detectors. Also, the effect of input launch conditions is examined and a possible standardized OTDR test procedure is proposed. Using these su… more
Date: June 1983
Creator: Danielson, B. L.
open access

Reference Flat Pulse Generator

Description: Introduction: A reference step-like pulse generator is described which has been developed at NBS. This generator can be used for accurately characterizing the step response of various kinds of trap ient recording equipment (oscilloscopes, waveform recorders, transient digitizers, etc.). Basic design principles are given as well as complete circuit diagrams and descriptions. An analysis of the output stage of the generator is presented together with the circuit models for developing a time-domai… more
Date: October 1983
Creator: Andrews, J. R.; Bell, B. A. & Baldwin, E. E.
open access

Introduction to STARPAC: the Standards Time Series and Regression Package

Description: From preface: STARPAC documentation is being published as a series of Technical Notes. This Note is the first in the series. It gives an overview of the STARPAC library, defines conventions used in the documentation, provides an example using STARPAC subroutines, and presents general background material. This Note includes information which is essential for using the STARPAC library, and users should be familiar with its contents before attempting to use any STARPAC subroutine.
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
open access

Nonlinear Least Squares Regression Using STARPAC: The Standards Time Series and Regression Package

Description: From preface: This Note documents 16 subroutines for nonlinear least squares regression. Twelve of these compute the least squares estimates, performing either weighted or unweighted analysis with either numerically approximated or user-supplied (analytic) derivatives. The other four are user-callable subroutines for two procedures used within the estimation code: the first selects optimum step sizes for approximating the partial derivatives of the model; and the second checks the validity of a… more
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
open access

An Equation of State for Fluid Ethylene

Description: Abstract: A thermodynamic property formulation for ethylene, developed as a part of a joint industry-government project, is presented. The formulation includes an equation of state, vapor pressure equation, and equation for the ideal gas heat capacity. The coefficients were determined by a least squares fit of selected experimental data. Comparisons of property values calculated using the equation of state with measured values are given. The equation of state is not valid in the critical region… more
Date: July 1981
Creator: McCarty, Robert D. & Jacobsen, Richard T.
open access

Measurement of Optical Fiber Bandwidth in the Frequency Domain

Description: Abstract: The design, evaluation, and performance of a system for determining the magnitude of the transfer function (hence, the bandwidth) of a multimode optical fiber are presented. The system operates to about 1450 MHz using a tracking generator/spectrum analyzer combination for narrowband detection. It is constructed, almost entirely, from commercially available components. The system is less complex and easier to use than an equivalent time domain system and the measurement precision is co… more
Date: September 1981
Creator: Day, G. W.
open access

Thermophysical Properties of Isobutane from 114 to 700 K at Pressures to 70 MPa

Description: Abstract: Using a modified version of the nonanalytic equation of state, thermophysical properties of isobutane are derived from physical properties data and are tabulated at integral temperatures over the entire range of fluid states from 114 to 700 K along isobars at pressures to 70 MPa. Results include dielectric constants, densities, enthalpies, entropies, equation of state, internal energies, isobars, isochores, isotherms, Joule-Thomson inversion, heats of vaporization, melting line, ortho… more
Date: January 1982
Creator: Goodwin, Robert D. & Haynes, William M.
open access

Electrical Properties of Materials and Their Measurement at Low Temperatures

Description: Abstract: A review is given of the electrical resistance of materials at cryogenic temperatures. Measurement techniques, the data base, and uses of the data are presented. The emphasis is on metals and alloys of technological importance; a toxic which covers a large range of materials. Similarly, the treatment of theory and of measurement techniques is primarily for the user interested in the more practical aspects of the subject. In every instance, however, references are given which allow the… more
Date: March 1982
Creator: Fickett, F. R.
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