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X-ray measurements of stresses and defects in EFG and large grained polycrystalline silicon ribbons. First quarterly report

Description: The first model of a modified Bond goniometer has been built and tested for the precision measurement of interplanar spacings in Si-single crystals. A change in interplanar spacing ..delta..d/d approximately = to +- 10/sup -5/ can be detected which corresponds to surface stresses of the order of +- 1000 psi. A second version of the goniometer is being assembled incorporating a removable microscope for precision alignment of the Si-strip into the primary X-ray beam.
Date: January 1, 1978
Creator: Wagner, C.N.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Precipitation kinetics of a continuous precipitator, with application to the precipitation of ammonium polyuranate

Description: A mathematical model describing the kinetics of continuous precipitation was developed which accounts for crystal nucleation, crystal growth, primary coagulation, and secondary coagulation. Population density distributions, average particle sizes, dominant particle sizes, and suspension density fractions of the crystallites, primary agglomerates, and secondary agglomerates leaving the continuous precipitator can be determined. This kinetic model was applied to the continuous precipitation of am… more
Date: April 1, 1978
Creator: Hoyt, R.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Homogenization of arc-melted uranium-6 weight percent niobium alloy ingots

Description: Microsegregation and macrosegregation in uranium-6 niobium arc-melted ingots were characterized by electron microprobe analysis. Homogenization studies determined that microsegregation can be eliminated by heat treating the alloy for six hours at 1100/sup 0/C. Extensive homogenization did not eliminate macrosegregation (banding) from the as-cast alloy, but a mathematical model describing banding and coring indicated that banding could possibly be eliminated by working prior to homogenization.
Date: January 31, 1978
Creator: Snyder, W. B., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thin films of gallium arsenide on low-cost substrates. Quarterly technical progress report No. 6 and topical report No. 2, January 1, 1978-April 1, 1978

Description: The metalorganic chemical vapor deposition (MO-CVD) technique has been applied to the growth of thin films of GaAs and GaAlAs on inexpensive polycrystalline or amorphous substrate materials (primarily glasses and metals) for use in fabrication of large-area low-cost photovoltaic device structures. Trimethylgallium (TMG), arsine (AsH/sub 3/), and trimethylaluminum (TMAl) are mixed in appropriate concentrations at room temperature in the gaseous state and pyrolyzed at the substrate, which is heat… more
Date: April 1, 1978
Creator: Ruth, R. P.; Dapkus, P. D.; Dupuis, R. D.; Campbell, A. G.; Johnson, R. E.; Manasevit, H. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of grain boundary segregation using the Auger electron emission technique. Annual technical progress report, VIII, January 1-December 31, 1978

Description: The susceptibility of nickel-copper alloys to liquid metal embrittlement was studied by Auger spectroscopy. Alloys corresponding to Monel 400 with various levels of additional phosphorous were employed and were given various thermal treatments to control the extent of segregation. Segregation of phosphorous to the boundaries, with accompanying decreases in copper and nickel concentrations, greatly reduces susceptibility to intergranular embrittlement by mercury.
Date: January 1, 1978
Creator: Stein, D. F.; Heldt, L. A. & Funkenbusch, A. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Immobilization of radioactive waste in glass matrices

Description: A promising process for long-term management of high-level radioactive waste is to immobilize the waste in a borosilicate glass matrix. Among the most important criteria characterizing the integrity of the large-scale glass-waste forms are that they possess good chemical stability (including low leachability), thermal stability, mechanical integrity, and high radiation stability. Fulfillment of these criteria ensures the maximum margin of safety of glass-waste products, following solidification… more
Date: January 1, 1978
Creator: Wicks, G. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microstructural interactions of geologic media with waste radionuclides

Description: A preliminary investigation of the microstructure of four geologic media was taken to examine the interaction of Cs, Sr, Gd and U with those media. Since K/sub D/ measurements often vary by more than an order of magnitude on rocks of the same strata separated by several feet, it was probable that minor rock components play an important role in radionuclide sorption. A qualitative analysis of the rock surfaces after equilibration with solutions of Cs/sup +/, Sr/sup + +/, Gd/sup + + +/ and UO/sub… more
Date: March 1, 1978
Creator: Hinkebein, T. E. & Hlava, P. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Deformation of superplastic alloys at relatively low strain rates

Description: The superplastic and sub-superplastic creep properties of Pb-Sn eutectic and Al-Zn eutectoid alloys were studied. Various thermomechanical treatments we tested to check the possibilities of whether the subsuperplastic deformation mechanism is affected by these treatments. All thermomechanical histories were found to reveal the same stress exponent, which is believed to be indicative of the predominant mechanism. The mechanical data in the low stress region lead us to suggest that dislocation gl… more
Date: February 1, 1978
Creator: Grivas, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Powder metallurgical processing of magnetostrictive materials based on rare earth-iron intermetallic compounds

Description: Procedures are described for fabrication of high density rare earth-iron magnetostrictive compounds by powder metallurgical techniques. The fabrication involves a sequence of steps which includes preparing the pre-alloyed compounds, pulverizing them into a fine powder, compacting in suitable sizes and shapes, and sintering. Samples prepared by these procedures are carefully characterized by scanning electron microscopy, x-ray diffraction, dilatometry, and magnetic measurements. Process steps ar… more
Date: January 1, 1978
Creator: Malekzadeh, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ductile superconducting wire through novel metallurgical techniques

Description: Ductile superconducting wires can be formed through controlled precipitation of the A15 phase from supersaturated solution in the solid state. The current research has focused on melting, homogenizing, and thermomechanically processing supersaturated solutions of Ga in V. A diagram of the rolling process is given. (SDF)
Date: January 1, 1978
Creator: Hong, M. & Morris, J.W. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stress relaxation and hillock growth in thin films

Description: The relaxation of thermal stress in a thin film adhering to a substrate of differing expansion coefficient is discussed. Good agreement is found between literature data on relaxation during isothermal anneals of Pb films at up to 350/sup 0/K and model calculations based on a state variable description of plastic flow. The stress system during relaxation is explored, and the absence of diffusional creep is explained. The plasticity-dominated relaxation process suggested by this analysis is shown… more
Date: January 1, 1978
Creator: Jackson, M. S. & Li, C. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Postirradiation Examinations of Fuel Pins from the GCFR F-1 Series of Mixed-Oxide Fuel Pins at 5. 5 at. % Burnup

Description: Postirradiation examinations were performed on five fuel pins from the Gas-Cooled Fast-Breeder Reactor F-1 experiment irradiated in EBR-II to a peak burnup of approximately 5.5 at. %. These encapsulated fuel pins were irradiated at peak-power linear ratings from approximately 13 to 15 kW/ft and peak cladding inside diameter temperatures from approximately 625 to 760°C. The maximum diametral change that occurred during irradiation was 0.2% .delta.D/D₀. The maximum fuel-cladding chemical interact… more
Date: May 1978
Creator: Johnson, C. E. & Strain, R. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thin films of gallium arsenide on low-cost substrates. Quarterly technical progress report No. 8 and topical report No. 3, April 2-July 1, 1978

Description: The seventh quarter of work on the contract is summarized. The metalorganic chemical vapor deposition (MO-CVD) technique has been applied to the growth of thin films of GaAs and GaAlAs on inexpensive polycrystalline or amorphous substrate materials (primarily glasses and metals) for use in fabrication of large-area low-cost photovoltaic device structures. Trimethylgallium (TMG), arsine (AsH/sub 3/), and trimethylaluminum (TMAl) are mixed in appropriate concentrations at room temperature in the … more
Date: July 1, 1978
Creator: Ruth, R. P.; Dapkus, P. D.; Dupuis, R. D.; Johnson, R. E.; Manasevit, H. M.; Moudy, L. A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Image processing of small protein-crystals in electron microscopy

Description: This electron microscope study was undertaken to determine whether high resolution reconstructed images could be obtained from statistically noisy micrographs by the super-position of several small areas of images of well-ordered crystals of biological macromolecules. Methods of rotational and translational alignment which use Fourier space data were demonstrated to be superior to methods which use Real space image data. After alignment, the addition of the diffraction patterns of four small ar… more
Date: November 1, 1978
Creator: Feinberg, D.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Kinetic study of the formation of the superconducting A15 phase in the Nb-Al-Si system

Description: So far, aluminum-containing superconductors showed excellent critical fields and temperatures. Powder Metallurgy shows the most promise in producing these particular kinds of superconductors in the near future. The scope of this research is to apply a kinetic study to observe the behavior of the Nb(Al,Si) system at elevated temperatures. From such observations, an optimized method of obtaining the A15 superconducting phase can be achieved. This study has resulted in a two step heat treatment to… more
Date: December 1, 1978
Creator: Binh-Phung
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of the microstructure of ductile alloys on solid particle erosion behavior

Description: The effect of microstructure of two phase alloys, consisting of a softer, ductile matrix and a harder interspersed phase, on erosion behavior was determined. The stress and strain distribution in a two phase alloy where the second, hard phase is a distribution of particles in a more ductile matrix was calculated. It was determined that a spheroidized 1075 carbon steel eroded 30 percent less than a pearlitic microstructure of the same steel even though the spherodized form was 21 R/sub B/ points… more
Date: October 1, 1978
Creator: Levy, A. V. & Jahanmir, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Thin films of gallium arsenide on low-cost substrates. Quarterly technical progress report No. 5 and topical report No. 1, October 2, 1977-December 31, 1977

Description: The metalorganic chemical vapor deposition (MO-CVD) technique has been applied to the growth of thin films of GaAs and GaAlAs on inexpensive polycrystalline or amorphous substrate materials (primarily glasses and metals) for use in fabrication of large-area low-cost photovoltaic device structures. Trimethylgallium (TMG), arsine (AsH/sub 3/), and trimethylaluminum (TMAl) are mixed in appropriate concentrations at room temperature in the gaseous state and pyrolyzed at the substrate, which is heat… more
Date: January 1, 1978
Creator: Ruth, R. P.; Dapkus, P. D.; Dupuis, R. D.; Johnson, R. E.; Manasevit, H. M.; Moudy, L. A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High-temperature fuel cell research and development. Final technical status report, June 1977-September 1978

Description: An initial survey of the literature produced a list of ceramic materials with properties which made them potential candidates for use in molten-carbonate fuel cell tiles or electrodes. Seven of the materials in the original list were dropped from consideration because of unfavorable thermodynamic properties; four materials were set aside because of high cost, lack of availability, or fabrication difficulties. Thirteen compositions were tested statically at 1000 K in a Li/sub 2/CO/sub 3/-K/sub 2… more
Date: October 15, 1978
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Laser-induced fluorescence line narrowing of Eu/sup 3 +/ in lithium borate glass

Description: Laser-induced fluorescence line narrowing reveals structural changes in Eu/sup 3 +/ doped borate glasses as a function of Li/sub 2/O network modifier concentration. These changes are discussed in terms of different coordination and bonding and possible phase separation.
Date: January 1, 1978
Creator: Hegarty, J.; Yen, W. M.; Weber, M. J. & Blackburn, D. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Damage of metal surfaces by a hot, dense deuterium plasma

Description: The effect of differences in alloy chemistry and systematic changes in microstructural interface density on the occurrence of unipolar arcing was studied. The effect of thermionic emission is examined by comparing the refractory metals W, Nb, and Nb-751 alloy to the non-refractory stainless steels, AISI 304, 316 and Nimonic PE-16. The effect of alloying additions is examined by comparing Mo containing 316 and Mo free 304 stainless steels as well as Zr containing Nb-751 and Zr free Nb. The effec… more
Date: January 1, 1978
Creator: Panayotou, N.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design of Duplex Low-Carbon Steels With Carbide Forming Elements

Description: The design of duplex ferrite-martensite (DFM) steels with carbide forming elements were investigated. The alloys Fe/0.14 C/1.45 Si/X (X being the substitutional alloying element of Mos or Nb) were selected. The DFM microstructures are controlled by the type of alloy element and the subsequent thermal treatment. The tensile properties of specimens subjected to either the intermediate quench (IQ) or the intermediate air cool (IAC) heat treatments have been correlated with their respective microst… more
Date: December 1, 1978
Creator: Costello, P. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cadmium sulfide/copper sulfide heterojunction cell research. Technical progress report No. 4, July 1-September 30, 1978

Description: Important advances have been made in five technical areas during this quarter: topological investigations of film materials and cells, characterization of current transport and collection in Cu/sub 2/S/CdS cells, preparation and application of small area film cells, correlation of photoresponse image and structural features in film cells and means of preparing (CdZn)S alloy films. The use of potassium cyanide etching of Cu/sub 2/S layers on polycrystalline CdS films defined areas 1 to 5 ..mu..m… more
Date: November 20, 1978
Creator: Szedon, J. R.; Shirland, F. A.; Biter, W. J.; Stoll, J. A.; Dickey, H. C. & O'Keeffe, T. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thin films of silicon on low-cost substrates. Quarterly report No. 5, January 1-March 31, 1978

Description: Parametric studies of silicon deposition were conducted employing the horizontal Energy Beam system. Chemical equilibrium calculations pertaining to the Energy Beam deposition conditions were performed. These calculations indicated that the reaction efficiency for hydrogen reduction of silicon tetrachloride is over 95% for any chlorosilane concentration at the Energy Beam temperature of 4300/sup 0/K. Because lower temperatures exist near the substrate surfaces, the kinetics of establishing the … more
Date: January 1, 1978
Creator: Sarma, K.R.; Gurtler, R.W.; Baghdadi, A. & Cota, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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