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Technology of Liquid Helium

Description: From Abstract: "This treatise is a source document containing information on helium resources, production, conservation, thermodynamic properties, liquefaction and refrigeration techniques, transportation and storage of liquid and safety requirements. It also contains a discussion of uses for liquid and cold gas in cryoelectronics, superconductivity, bubble chambers, cryopumping and missile and space systems."
Date: October 1968
Creator: Kropschot, R. H.; Birmingham, B. W. & Mann, D. B.
Partner: UNT Libraries Government Documents Department

The 1958 He4 Scale of Temperatures: Part 1. Introduction, Part 2. Tables for the 1958 Temperature Scale

Description: Report containing information regarding He4 vapor pressure measurement as of 1958, the recent history of the vapor pressure temperature scale, and a series of tables containing these measurements.
Date: June 17, 1960
Creator: Brickwedde, F. G. (Ferdinand Graft), 1903-; van Dijk, H.; Durieux, M.; Clement, J. R. & Logan, J. K.
Partner: UNT Libraries Government Documents Department

Helium: Bibliography of Technical and Scientific Literature from Its Discovery (1868) to January 1, 1947

Description: Scope of Bibliography: "This bibliography contains references to all technical and scientific articles pertaining to helium that are known by Bureau of Mines scientists to have been published before January 1, 1947. It also contains many references to articles containing information on helium that have appeared in medical journals and some popular magazines."
Date: 1952
Creator: Wheeler, Henry P., Jr. & Swenarton, Louise B.
Partner: UNT Libraries Government Documents Department

The Recombination Rate Coefficient of Molecular Helium Ions in a Pulsed Afterglow at 1.86 Torr

Description: The recombination rate coefficient for molecular helium ions has been measured in a pulsed afterglow at 1.86 Torr as a function of electron temperature and electron density without making a priori assumptions about the functional dependence. The concentrations of the molecular ions and electrons were measured and the source terms for the molecular ions were included in the rate equation.
Date: August 1972
Creator: Hicks, Helen Segrave
Partner: UNT Libraries

Measurement of Helium-3/Helium-4 Ratios in Soil Gas at the 618-11 Burial Ground

Description: Seventy soil gas-sampling points were installed around the perimeter of the 618-11 Burial Ground, approximately 400 feet downgradient of well 699-13-3A, and in four transects downgradient of the burial ground to a maximum distance of 3,100 feet. Soil gas samples were collected and analyzed for helium-3/helium-4 ratios from these 70 points. Helium-3/helium-4 ratios determined from the soil gas sampling points showed significant enrichments, relative to ambient air helium-3 concentrations. The highest concentrations were located along the northern perimeter of the burial ground. Helium-3/helium-4 ratios (normalized to the abundances in ambient air) ranged from 1.0 to 62 around the burial ground. The helium-3/helium-4 ratios from the 4 transect downgradient of the burial ground ranged from 0.988 to 1.68. The helium-3/helium-4 ratios from around the burial ground suggest there is a vadose zone source of tritium along the north side of the burial ground. This vadose zone source is likely the source of tritium in the groundwater. The helium-3/helium-4 ratios also suggest the groundwater plume is traveling east-northeast from the burial ground and the highest groundwater tritium value may be to the north of well 699-13-3A. Finally, there appears to be no immediately upgradient sources of tritium impacting the burial ground since all the upgradient helium-3/helium-4 ratios are approximately 1.0.
Date: October 31, 2001
Creator: Olsen, Khris B.; Dresel, P Evan & Evans, John C.
Partner: UNT Libraries Government Documents Department

Conversion of Inviscid Normal-Force Coefficients in Helium to Equivalent Coefficients in Air for Simple Shapes at Hypersonic Speeds

Description: A correlation factor applicable for converting inviscid aerodynamic normal-force coefficients of simple shapes in helium to equivalent coefficients in air is found by using calculations based on the shock-expansion method at Mach numbers of 12, 16, and 20.
Date: October 1956
Creator: Mueller, James N.
Partner: UNT Libraries Government Documents Department

Helium Tables

Description: These tables are intended to provide a standard method and to facilitate the calculation of the quantity of "Standard Helium" in high pressure containers. The research data and the formulas used in the preparation of the tables were furnished by the Research Laboratory of Physical Chemistry, of the Massachusetts Institute of Technology.
Date: January 1928
Creator: Havill, Clinton H.
Partner: UNT Libraries Government Documents Department

Method to control the amount of helium during leak testing

Description: The purpose of this paper is to demonstrate a method for limiting the amount of helium administered during leak testing and provide a method for keeping the atmospheric helium in a location to a minimum to eliminate backstreaming into the system. This method utilizes the permeability of a balloon. The transporting of helium to the leak check area is also safer by not requiring a cylinder in the leak check location. Utilizing the many shapes of balloons and partially filling of the balloon, any configuration can deliver helium to the leak location. The balloon I filled for the test fell to the floor with the amount of helium I put into the balloon.
Date: March 29, 2002
Creator: Frank E. Jurvic, Jr.
Partner: UNT Libraries Government Documents Department

A Study of Minority Atomic Ion Recombination in the Helium Afterglow

Description: Electron-ion recombination has been under study for many years, but comparisons between theory and experiment have been very difficult, especially for conditions where the ion under evaluation was a minority in concentration. This study describes a direct measurement of the recombination-rate coefficient for the recombination of minority as well as majority ions in the afterglow.
Date: August 1972
Creator: Wells, William E.
Partner: UNT Libraries

A study of transient molecular ions using a resonant microwave cavity as a probe

Description: The microwave-resonant-cavity technique was employes as a probe to determine the presence of molecular ions of helium in a d.c.-discharge, helium-plasma filament placed coaxially in a TM010 mode cavity. The cavity-resonance profile was displayed on an oscilloscope, and the nature of the perturbation of this resonance was used to determine the nature of the ions present in the plasma stream.
Date: December 1973
Creator: Congleton, Michael William
Partner: UNT Libraries

Equations, Tables, and Figures for Use in the Analysis of Helium Flow at Supersonic and Hypersonic Speeds

Description: Report presenting equations, tables, and figures for use in the analysis of helium flow at supersonic and hypersonic speeds. Tables are provided for useful dimensionless ratios for continuous one-dimensional flow and normal-shock waves as functions of Mach number. The oblique-shock characteristics of wedges and cones in helium at various Mach numbers are also presented.
Date: September 1957
Creator: Mueller, James N.
Partner: UNT Libraries Government Documents Department

Variation with Electron Temperature of the Intensity Ratio of a Pair of Helium Spectral Lines

Description: Abstract: "The dependence on mean electron kinetic energy of the ratio of intensities of [lambda]5015[HeI] and [lambda]4686[HeII] has been calculated. A low-density plasma is considered, the principal assumptions being that the reaction processes are governed by electron collisions and the electron energy distribution is Maxwellian. The results show a fairly large variation of the intensity ratio within the range of 3 to 7 ev."
Date: June 19, 1958
Creator: Howard, John C.
Partner: UNT Libraries Government Documents Department

Vacuum Probe, Standard Leaks, and Needle Valve for Use with the Helium Leak Detector

Description: The following report is split into four parts describing the usage of a vacuum probe for leak hunting with the Helium Leak Detector, the two types of Standard Leaks that were designed to measure the sensitivity of the detector, the development of a needle valve adjusted for controlling the flow of a standard mixture of helium and air into the leak detector for a sensitivity check by the single leak method, and a worm and gear adjustment developed to facilitate throttling of the Helium Leak Detector on a vacuum header equipped with the 3/8" Kerotect angle valve.
Date: August 1945
Creator: Samuel, A. J.
Partner: UNT Libraries Government Documents Department

Cryogenic design of the liquid helium experiment ``critical dynamics in microgravity``

Description: Although many well controlled experiments have been conducted to measure the static properties of systems near criticality, few experiments have explored the transport properties in systems driven far away from equilibrium as a phase transition occurs. The cryogenic design of an experiment to study the dynamic aspect of critical phenomena is reported here. Measurements of the thermal gradient across the superfluid (He II) -- normal fluid (He I) interface in helium under microgravity conditions will be performed as a heat flux holds the system away from equilibrium. New technologies are under development for this experiment, which is in the definition phase for a space shuttle flight.
Date: October 1, 1995
Creator: Moeur, W.A.; Adriaans, M.J.; Boyd, S.T.; Strayer, D.M. & Duncan, R.V.
Partner: UNT Libraries Government Documents Department