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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. & Swenarton, Louise B.
Partner: UNT Libraries Government Documents Department

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

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

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

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

The Helium-3 Shortage: Supply, Demand, and Options for Congress

Description: The world is experiencing a shortage of helium-3, a rare isotope of helium with applications in homeland security, national security, medicine, industry, and science. Federal officials have testified that the shortage is acute and, unless alternatives are found, will affect federal investments in homeland security, scientific research, and other areas. This report discusses the nature of the shortage; federal actions undertaken so far to address it; current and potential sources of helium-3 and options for increasing the supply; current and projected uses of helium-3 and options for reducing the demand; and options for allocating the supply if it continues to fall short of demand.
Date: December 22, 2010
Creator: Shea, Dana A. & Morgan, Daniel
Partner: UNT Libraries Government Documents Department

Symmetrized complex amplitudes for He double photoionization from the time-dependent close coupling and exterior complex scaling methods

Description: Symmetrized complex amplitudes for the double photoionization of helium are computed by the time-dependent close-coupling and exterior complex scaling methods, and it is demonstrated that both methods are capable of the direct calculation of these amplitudes. The results are found to be in excellent agreement with each other and in very good agreement with results of other ab initio methods and experiment.
Date: June 1, 2004
Creator: Horner, D.A.; Colgan, J.; Martin, F.; McCurdy, C.W.; Pindzola, M.S. & Rescigno, T.N.
Partner: UNT Libraries Government Documents Department

HELIUM THREE

Description: A review is given of the present state of knowledge concerning the condensed phases of He{sup 3}. Attention is confined to the pure substance, and emphasis is placed upon the theoretical understanding of the material.
Date: September 11, 1962
Creator: Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department

Helium bubble linkage and the transition to rapid He release in aging Pd tritide.

Description: A model is presented for the linking of helium bubbles growing in aging metal tritides. Stresses created by neighboring bubbles are found to produce bubble growth toward coalescence. This process is interrupted by the fracture of ligaments between bubble arrays. The condition for ligament fracture percolates through the material to reach external surfaces, leading to material micro-cracking and the release of helium within the linked-bubble cluster. A comparison of pure coalescence and pure fracture mechanisms shows the critical HeM concentration for bubble linkage is not strongly dependent on details of the linkage process. The combined stress-directed growth and fracture process produces predictions for the onset of rapid He release and the He emission rate. Transition to this rapid release state is determined from the physical size of the linked-bubble clusters, which is calculated from dimensional invariants in classical percolation theory. The result is a transition that depends on material dimensions. The onset of bubble linkage and rapid He release are found to be quite sensitive to the bubble spacing distribution, which is log-normal for bubbles nucleated by self-trapping.
Date: February 1, 2006
Creator: Cowgill, Donald F.
Partner: UNT Libraries Government Documents Department

Thermomagnetic Phenomena in Antimony at Liquid Helium Temperatures

Description: The purpose of this investigation was to study head-transport phenomena in a single crystal of antimony at liquid helium temperatures. In particular, the longitudinal and transverse components of the thermal resistivity tensor were measured as a function of magnetic field up to eighteen kilogauss.
Date: January 1964
Creator: Haywood, Charles Thomas
Partner: UNT Libraries

The Helium-3 Shortage: Supply, Demand, and Options for Congress

Description: The world is experiencing a shortage of helium-3, a rare isotope of helium with applications in homeland security, national security, medicine, industry, and science. Federal officials have testified that the shortage is acute and, unless alternatives are found, will affect federal investments in homeland security, scientific research, and other areas. This report discusses the nature of the shortage; federal actions undertaken so far to address it; current and potential sources of helium-3 and options for increasing the supply; current and projected uses of helium-3 and options for reducing the demand; and options for allocating the supply if it continues to fall short of demand.
Date: September 21, 2010
Creator: Shea, Dana A. & Morgan, Daniel
Partner: UNT Libraries Government Documents Department