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Atlas of atomic spectral lines of plutonium emitted by an inductively coupled plasma

Description: Optical emission spectra from high-purity Pu-242 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 2280 to 7008 Angstrom wavelength range are presented along with general commentary on ICP-Pu spectroscopy.
Date: September 1, 1986
Creator: Edelson, M. C.; DeKalb, E. L.; Winge, R. K. & Fassel, V. A.
Partner: UNT Libraries Government Documents Department
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Extraction and identification of organic materials present in soot from a natural gas flame

Description: Aliphatic and polynuclear aromatic hydrocarbons are readily extracted from soot formed from a natural gas flame using methylene chloride and ultrasonic agitation. Identification of 24 organic compounds via capillary column GC retention times and GC-MS data is reported along with details of experimental procedures.
Date: January 1, 1978
Creator: Vick, R.D. & Avery, M.J.
Partner: UNT Libraries Government Documents Department
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Recent results from studies of non-gaseous fission products with TRISTAN II

Description: A new in-beam target ion-source combination has been installed at the TRISTAN isotope separator facility. Mass separated beams of nongaseous fission products are now available for study. Studies of levels in even-even Cd and Sn nuclei populated through the decay of Ag and In fission products are described, and an evaluation of possibilities for future research is made.
Date: March 1, 1978
Creator: Hill, J. C.
Partner: UNT Libraries Government Documents Department
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Fabrication of superconducting wire composites by directional solidification. Yearend report on project

Description: Progress is reported for a program to develop a new process for producing composite Nb/sub 3/Sn/Cu superconducting wires and evaluating their critical current densities and the stress dependence of their critical currents. The process involves directional solidification of Cu--Nb or Cu--Nb--Sn alloys. (SDF)
Date: October 1, 1977
Creator: Verhoeven, J. D.; Gibson, E. D.; Finnemore, D. & Ostenson, G.
Partner: UNT Libraries Government Documents Department
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Health and environmental effects of refuse derived fuel (RDF) production and RDF/coal co-firing technologies

Description: Six facilities, representing the scope of different co-firing techniques with their associated RDF production systems were reviewed in detail for combustion equipment, firing modes, emission control systems, residue handling/disposal, and effluent wastewater treatment. These facilities encompass all currently operational or soon to be operational co-firing plants and associated RDF production systems. Occupational health and safety risks for these plants were evaluated on the basis of fatal and… more
Date: October 1, 1981
Creator: O'Toole, J. J.; Wessels, T. E.; Lynch, J. F.; Fassel, V. A.; Lembke, L. L.; Kniseley, R. N. et al.
Partner: UNT Libraries Government Documents Department
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Magnetization of in situ multifilamentary superconducting Nb/sub 3/Sn-Cu composites

Description: Magnetic properties are reported for in situ superconducting Nb/sub 3/Sn composites that have exhibited attractive electrical properties and superior mechanical characteristics. Magnetization measurements were conducted up to 4 T at 4.2 K on a variety of samples of different sizes and twist pitches, and the results are presented in absolute M-H curves and losses per cycle. It is observed that the magnetization of such composites is generally proportional to the size of the wire (approx. 0.25 to… more
Date: January 1, 1980
Creator: Shen, S. S. & Verhoeven, J. D.
Partner: UNT Libraries Government Documents Department
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Quarterly report, 1 January-31 March 1980

Description: Progress is reported in the following areas of research: characterization of organic pollutants emitted by fossil fuel processing and energy generating plants; environmental effects of using municipal solid wastes as a supplementary fuel; microbiological air quality at the Ames Municipal Solid Waste Recovery System; solid waste to methane environmental study; x-ray and ultraviolet excited optical luminescence (XEOL, UVEOL) of carcinogens - analytical possibilities; laser pumped luminescence (LP… more
Date: May 1, 1980
Partner: UNT Libraries Government Documents Department
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Quarterly report, 1 October-31 December 1979

Description: Progress is reported in the following areas of research: characterization of organic pollutants emitted by fossil fuel processing and energy generating plants; environmental effects of using municipal solid wastes as a supplementary fuel; microbiological air quality at the Ames Municipal Solid Waste Recovery System; solid waste to methane environmental study; x-ray and ultraviolet excited optical luminescence (XEOL, UVEOL) of carcinogens - analytical possibilities; laser pumped luminescence (LP… more
Date: March 1, 1980
Partner: UNT Libraries Government Documents Department
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Investigations of several interference effects in high frequency plasmas of analytical importance

Description: Investigations of the extent to which certain inter-element or interference effects occur in a radiofrequency-excited inductively coupled plasma (ICP) are reported. Under conditions normally employed for analytical purposes, it is shown that: (a) two solute vaporization interferences often observed in flames are eliminated or reduced to negligible proportions in the plasma; (b) increasing concentrations of an easily ionizable element (Na) up to concentrations of 6900 ..mu..g/ml exerted an unusu… more
Date: February 1, 1977
Creator: Larson, G.F.
Partner: UNT Libraries Government Documents Department
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Electromigration of hydrogen and deuterium in vanadium, niobium, and tantalum

Description: The electric mobility and effective valence of hydrogen and deuterium in vanadium, niobium, tantalum and three niobium-tantalum alloys were measured. A resistance technique was used to directly determine the electric mobility of hydrogen and deuterium at 30/sup 0/C while a steady-state method was used to measure the effective valence. The use of mass spectrographic techniques on a single specimen which contained both hydrogen and deuterium greatly increased the precision with which the isotope … more
Date: October 1, 1977
Creator: Jensen, C. L.
Partner: UNT Libraries Government Documents Department
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Study of nuclei far from stability with TRISTAN II at the High Flux Beam Reactor at Brookhaven

Description: The ISOL facility TRISTAN II is described, and its expected capabilities on-line to the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory are discussed. In particular, the range of isotopes expected to be available and possible experimental studies of the short-lived fission-product isotopes are described. Background information consisting of an overview of the study of nuclei far from stability and a survey of existing ISOL facilities is presented in order to aid in evaluating th… more
Date: October 1, 1977
Creator: Wohn, F.K.
Partner: UNT Libraries Government Documents Department
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Electrical and Magnetic Properties of Holmium Single Crystals

Description: Magnetic moment measurements are made on holmium single crystals (hcp) from 1.3 to 300 deg K in magnetic fields from 250 to 18,000 Oe, with the field applied along the c axis, the a axis, and a (1010) direction. The STA1010! direction is the direction of easy magnetization with an extrapolated effective moment per atom at saturation of 10.34 Bohr magnetons. Basal plane measurements show antiferromagnetism below the Neel temperature of 132 deg K with basal plane anisotropy occurring below 80 deg… more
Date: September 15, 1962
Creator: Strandburg, D. L.; Legvold, S. & Spedding, F. H.
Partner: UNT Libraries Government Documents Department
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Crystal growth with parabolic interfaces

Description: A mathematical treatment is presented for the growth of dendrites or precipitates with parabolic interfaces. Two cases are considered in which the interfaces correspond to a paraboloid of revolution and a parabolic cylinder. For these interfaces, relationships between growth rate and supercooling are obtained for two general boundary conditions under the assumption that the temperature or concentration variation along the interface is finite and continuous. 1 figure.
Date: August 1, 1977
Creator: Trivedi, R.
Partner: UNT Libraries Government Documents Department
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Preparation of thin film solar cells under very low pressure conditions. Final report, October 1, 1976--September 30, 1977

Description: In this study the feasibility of fabricating backwall Schottky barrier polycrystalline solar cells under ultra-high vacuum conditions of 1 x 10/sup -10/ torr (N/sub 2/) was investigated. Thin films of electron beam vaporized silicon were deposited on cleaned metal substrates of tungsten, tantalum and hafnium. Mass spectra from the quadrapole residual gas analyzer were used to determine the partial pressure of peak heights of 13 residual gases during each processing step. During separate silicon… more
Date: January 1, 1977
Creator: Schmidt, F.A.; Shanks, H.R.; Bevolo, A.J. & Campisi, G.J.
Partner: UNT Libraries Government Documents Department
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Nuclear Contribution to the Heat Capacity of Terbium Metal

Description: The heat capacity of terbium metal was measured between 0.25 and 1.0 deg K. The high temperature data can be expressed as C = 28R x 10/sup -3/T/sup 2/ cal/ mole-deg. The data are compared with a Schottky formula for the heat capacity, assuming equal spacing between the nuclear hyperfine levels with an over-all spacing of beta = 0.45/ deg K, correspondlng to the high temperature expression above. The agreement is within experimental error except at the very lowest temperatures obtained. The effe… more
Date: October 1, 1961
Creator: Heltemes, E. C. & Swenson, C. A.
Partner: UNT Libraries Government Documents Department
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Developments and Applications of Electrophoresis and Small Molecule Laser Desorption Ionization Mass Spectrometry

Description: Ultra-sensitive native fluorescence detection of proteins with miniaturized one- and two-dimensional polyacrylamide gel electrophoresis was achieved with laser side-entry excitation, which provides both high excitation power and low background level. The detection limit for R-phycoerythrin protein spots in 1-D SDS-PAGE was as low as 15 fg, which corresponds to 40 thousand molecules only. The average detection limit of six standard native proteins was 5 pg per band and the dynamic range spanned … more
Date: December 1, 2007
Creator: Zhang, Hui
Partner: UNT Libraries Government Documents Department
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The Development and Optimization of Techniques for Monitoring Water Quality on-Board Spacecraft Using Colorimetric Solid-Phase Extraction (C-SPE)

Description: The main focus of this dissertation is the design, development, and ground and microgravity validation of methods for monitoring drinking water quality on-board NASA spacecraft using clorimetric-solid phase extraction (C-SPE). The Introduction will overview the need for in-flight water quality analysis and will detail some of the challenges associated with operations in the absence of gravity. The ability of C-SPE methods to meet these challenges will then be discussed, followed by a literature… more
Date: December 1, 2007
Creator: Hill, April
Partner: UNT Libraries Government Documents Department
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M5Si3(M=Ti, Nb, Mo) Based Transition-Metal Silicides for High Temperature Applications

Description: Transition metal silicides are being considered for future engine turbine components at temperatures up to 1600 C. Although significant improvement in high temperature strength, room temperature fracture toughness has been realized in the past decade, further improvement in oxidation resistance is needed. Oxidation mechanism of Ti{sub 5}Si{sub 3}-based alloys was investigated. Oxidation behavior of Ti{sub 5}Si{sub 3}-based alloy strongly depends on the atmosphere. Presence of Nitrogen alters th… more
Date: December 1, 2007
Creator: Tang, Zhihong
Partner: UNT Libraries Government Documents Department
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System Cost Analysis for an Interior Permanent Magnet Motor

Description: The objective of this program is to provide an assessment of the cost structure for an interior permanent magnet ('IPM') motor which is designed to meet the 2010 FreedomCAR specification. The program is to evaluate the range of viable permanent magnet materials for an IPM motor, including sintered and bonded grades of rare earth magnets. The study considers the benefits of key processing steps, alternative magnet shapes and their assembly methods into the rotor (including magnetization), and an… more
Date: August 1, 2008
Creator: Campbell, Peter
Partner: UNT Libraries Government Documents Department
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