UNT Libraries Government Documents Department - 7 Matching Results

Search Results

Results: 1 - 7
open access

Beam-Profile Measurement of Laser Pulses Using a Spatial Filter to Sample the Hermite Modes of a String of Pulses

Description: Abstract: As a first step in the development of a beam-profile measuring instrument for laser sources that is capable of determining the distribution of low-order (less than 25) Hermitian modes in a series of laser pulses, I designed and evaluated the three key parts of such an instrument. First, there is the telescope system which allows the incident laser beam to be phase, beamwidth, and beam center matched to the optical spatial filter. Second, there is a brief error analysis of the structur… more
Date: September 1982
Creator: Johnson, Eric Gunnar, Jr.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Report
open access

A Method to Quantify the Radiation Characteristics of an Unknown Interference Source

Description: From introduction: A new method for determining the radiation characteristics of leakage from electronic equipment for interference studies is described in this report. Basically, an unintentional leakage source is considered to be electrically small, and may be characterized by three equivalent orthogonal electric dipole moments and three equivalent orthogonal magnetic dipole moments. When an unknown source object is placed at the center of a transverse electromagnetic (TEM) cell, its radiated… more
Date: October 1982
Creator: Ma, Mark T. & Koepke, Galen H.
Item Type: Refine your search to only Report
open access

A System for Measuring Energy and Peak Power of Low-Level 1.064 [mu]m Laser Pulses

Description: From introduction: For the first time, transfer standards have been developed for measuring 1.064 Pm laser pulses of duration about 10-100 ns, peak irradiance of about 10-8-10-4 W/cm2, and fluences of about 10-16-10-11 J/cm2 . These energy and power measurement devices use PIN and APD silicon detectors, respectively, and can be used as stable transfer standards with total uncertainties (random errors computed at the 95 percent confidence level) of 10 to 15 percent. The system for calibrating th… more
Date: October 1982
Creator: Sanders, A. A. & Rasmussen, A. L.
Item Type: Refine your search to only Report
open access

Tests of Commercial Densimeters for LNG Service

Description: Abstract: Densimeters for liquefied natural gas (LNG) from four manufacturers were tested in liquid methane and an LNG-like mixture of methane, propane, and nitrogen in the density reference system (DRS). The calibration and performance of one type tested for the first time are reported. The stability of the calibrations and performances of three densimeters of a type previously tested have been examined and are also reported here.
Date: June 1982
Creator: Siegwarth, J. D. & LaBrecque, J. F.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Report
Back to Top of Screen