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Advanced Materials and Processes for High Energy Resolution Room Temperature Gamma Ray Spectrometers

Description: A significant amount of progress has been achieved in the development of the novel vacuum distillation method described in the proposal. The process for the purification of Te was fully developed and characterized in a series of trials. The purification effect was confirmed with GDMS sample analysis and indicates the process yields very high purity Te metal. Results of this initial process study have been submitted for publication in the Proceedings of the SPIE and will be presented on August 2… more
Date: December 12, 2007
Creator: McGregor, Douglas S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of effects of impurities intentionally incorporated into silicon. Final report, Feburary 1, 1977--December 1, 1977

Description: A methodology has been developed and implemented to allow silicon samples containing intentionally incorporated impurities to be fabricated into finished solar cells under carefully controlled conditions. The electrical and spectral properties were then measured for each group processed, and this data, along with all the material, (cells and scrap) were delivered to JPL for further analysis. All 33 lots of Group ''C'', 14 lots of Group ''CM'' and 16 lots … more
Date: December 15, 1977
Creator: Uno, F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Critical currents, magnetic relaxation, and microstructure in zone-melted YBa sub 2 Cu sub 3 O sub x

Description: Extruded YBa{sub 2}Cu{sub 3}O{sub x} wires have been zone-melted to develop highly textured microstructures. The zone-melted wires exhibit large magnetic hysteresis and transport J{sub c} values relative to conventional bulk YBa{sub 2}Cu{sub 3}O{sub x}. Transmission electron microscopy observations indicate unique grain boundary features which are likely to be responsible for reduced weak-link effects. Large amounts of intragranular defects such as dislocations and Y{sub 2}BaCuO{sub 5} particle… more
Date: January 1, 1990
Creator: Shi, Donglu; Chen, J.G.; Xu, Ming; Goretta, K.C. (Argonne National Lab., IL (USA)); McGinn, P.J. & Chen, W.H. (Notre Dame Univ., IN (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Czochralski growth of gallium indium antimonide alloy crystals

Description: Attempts were made to grow alloy crystals of Ga{sub 1{minus}x}In{sub x}Sb by the conventional Czochralski process. A transparent furnace was used, with hydrogen purging through the chamber during crystal growth. Single crystal seeds up to about 2 to 5 mole% InSb were grown from seeds of 1 to 2 mole% InSb, which were grown from essentially pure GaSb seeds of the [111] direction. Single crystals were grown with InSb rising from about 2 to 6 mole% at the seed ends to about 14 to 23 mole% InSb at t… more
Date: February 1, 1998
Creator: Tsaur, S.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Float zone silicon sheet growth. Final report, September 23, 1993--December 31, 1996

Description: Energy Materials Research was organized in 1984. The specific objective of the company is to generate new concepts and to move targeted applications of newly developing technologies into commercial production. The initial technology described here is the outgrowth of a research program to develop concepts and techniques for low-cost energy production from renewable energy resources. The first major project implements an innovative process for the direct production of crystalline silicon sheet f… more
Date: April 1, 1997
Creator: Bleil, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Float zone silicon sheet growth. Quarterly report number 9, October 1--December 31, 1995

Description: This report discusses progress made in each of the following tasks: (1) heat pipe construction; (2) heat pipe heater and heat extraction system; (3) optical temperature monitoring system; (4) replenishment source development; (5) RF electrode assembly; (6) solid-liquid interface monitors; (7) ribbon seed preparation; and (8) overall systems assembly.
Date: February 1, 1996
Creator: Bleil, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Float zone silicon sheet growth. Quarterly report number 10, January 1--March 31, 1996

Description: During this period special attention has been paid to task number 8 as cited in the proposed statement of work. While the water cooling and power feed to the heaters and the primary and secondary electrodes has been completed and are functional, vacuum leaks developed during testing of the system. A multitude of stress induced pinhole vacuum leaks have seriously delayed the final system assembly. Progress has been extremely slow since the system has been completely disassembled and reassembled … more
Date: May 1, 1996
Creator: Bleil, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Float zone silicon sheet growth. Quarterly report number 12, July 1--September 30, 1996

Description: During this period continued attention has been paid to task number 8 as cited in the proposed statement of work. The water cooling and power feed to the heaters and the primary and secondary electrodes have been completed and are functional and all vacuum leaks have been repaired. Progress in the final assembly (task number 8) and the relevant additions to tasks numbered 3, 4, 5, 6 and 7 have occupied more than 80% of the time. Preparations have also been made for the completion of the final r… more
Date: December 31, 1996
Creator: Bleil, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Float zone silicon sheet growth. Technical progress report: Quarterly report Number 11, April 1--June 30, 1996

Description: During this period continued attention has been paid to task number 8 as cited in the proposed statement of work. While the water cooling and power feed to the heaters and the primary and secondary electrodes have been completed and are functional, vacuum leaks developed during testing of the system. A multitude of stress induced pinhole vacuum leaks which seriously delayed the final system assembly have been corrected. As a result, task No. 8 and the relevant changes in tasks numbered 3, 4, 5,… more
Date: September 1, 1996
Creator: Bleil, C.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Floating Substrate Process. Large-Area Silicon Sheet Task, Low-Cost Solar Array Project. Final report

Description: The work described was directed toward the demonstration of the practical feasibility of the Floating Substrate Process for the growth of silicon sheet. Supercooling of silicon--tin alloy melts was studied. Values as high as 78/sup 0/C at 1100/sup 0/C and 39/sup 0/C at 1200/sup 0/C were observed, corresponding to supersaturation parameter values 0.025 and 0.053 at 1050/sup 0/C and 1150/sup 0/C, respectively. The interaction of tin with silane gas streams was investigated over the temperature ra… more
Date: June 23, 1978
Creator: Garfinkel, M. & Hall, R.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Generalization of Internal Centrifugal Zone Growth of Metal-Ceramic Composites. Progress Report, December 1, 1974--August 31, 1975

Description: Objectives are (1) to develop a model of Internal Centrifugal Zone Growth (ICZG) and (2) to use this model to improve present ICZG systems. During the present year, models were developed for finite samples heated by finite induction coils. These models enable calculation of two-dimensional temperature profiles in solid samples. Molten zone shapes can be calculated provided that simplified boundary conditions for the rf field are employed. Experiments to test these models were conducted here and… more
Date: January 1, 1975
Creator: Sekerka, R. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Growth of high {Tc} superconducting fibers using a miniaturized laser-heated float zone process. Progress report, November 6, 1990--December 31, 1991

Description: This report summarizes the progress made on the project ``Growth of High {Tc} Superconducting Fibers Using a Miniaturized Laser-Heated Float Zone Process`` during the 14 month period from Nov. 6, 1990 to Dec. 31, 1991. The studies during this period focused primarily on phase diagram studies, phase relations in the calcium aluminate system and on Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} (BSCCO). Some work was also done on the Advanced Fiber Growing Station. Because of the complicated phase relatio… more
Date: December 1991
Creator: Feigelson, Robert S.; Route, R. K. & DeMattei, R. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hpvb and Hpvzm Shaped Growth of Cdznte, Cdse and Znse Crystals.

Description: High-pressure Bridgman (HPVB) and vertical zone melting (HPVZM) growth processes have been applied for the manufacturing of Cd{sub 1-x}Zn{sub x}Te (x = 0.04-0.2), CdSe and ZnSe crystal tapes with sizes up to 120 x 120 x 12 mm. The influences of the technological parameters describing the growth processes on the crystal quality and some selected material properties are discussed. The dependence of the inclusion (bubbles) content on the deviation from melt stoichiometry is determined. A method fo… more
Date: July 7, 2002
Creator: Kolesnikov, N. N.; James, R. B.; Berzigiarova, N. S. & Kulakov, M. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser-zone growth in a ribbon-to-ribbon (RTR) process silicon sheet growth development for the large area silicon sheet task of the low cost silicon solar array project. Technical quarterly report no. 8, April 1--June 30, 1978

Description: Further progress in growth rate has been made, reaching an area throughput rate of 38 cm/sup 2//min. This growth rate was achieved, using CVD feedstock, both with a 7.6 cm wide ribbon grown at 5 cm/min and a 5 cm wide ribbon grown at 7.6 cm/min. The 5 cm wide ribbon exhibited a dendritic structure; although the ribbon showed a tendency to buckle in the non-dendritic region, it was perfectly flat once the dendrites were firmly established. The 7.6 cm wide ribbon was non-dendritic, and had severe… more
Date: January 1, 1978
Creator: Baghdadi, A.; Gurtler, R. W.; Legge, R.; Sopori, B. & Ellis, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low-cost thin-film polycrystalline silicon solar cells. Quarterly project report No. 1, March 15, 1979-June 30, 1979

Description: The objective of this contract is to advance the thin film silicon solar cell technology developed at Southern Methodist University, Dallas, Texas, with a view toward achieving photovoltaic conversion efficiencies greater than 10% at a cost of $100 to $300/kWe. The technology developed at SMU consists of: (1) the purification of metallurgical silicon by acid extraction and phosphorus pentoxide treatment, (2) the preparation of metallurgical silicon substrates by the unidirectional solidificatio… more
Date: July 1, 1979
Creator: Crownover, J. D. & van der Leeden, G. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanical properties of melt-derived erbium oxide

Description: Erbium oxide (Er{sub 2}O{sub 3}) is a rare earth oxide that is chemically and thermally stable and has a melting point of 2,430 C. There is relatively little information available regarding single crystal growth of erbia or the properties of erbia. In this study, erbia single crystals have been grown in a Xenon Optical Floating Zone Unit (XeOFZ) capable of melting materials at temperatures up to 3,000 C. Erbia was melt synthesized in the XeOFZ unit in a container less fashion, proving for littl… more
Date: December 31, 1998
Creator: Neuman, A. D.; Blacic, M. J.; Platero, M.; Romero, R. S.; McClellan, K. J. & Petrovic, J. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Metallurgy Division Semiannual Progress Report for Period Ending October 10, 1954

Description: A study was made of fiber-texture type of preferred orientation in extruded Al rods and brass sheeting. Experiments to purify Zr by the zone- melting techniques were studied. Several transformation products of the decomposition of the BETA eutectoid of the Ag--Zr system were identified. The tempering of the martensitic structure of a hypoeutectoid Ag-- Zr was studied. Metallurgical treatments for the recovery of U from spent stainless steel fuel elements were investigated. Physical properties a… more
Date: August 31, 1955
Creator: Bridges, W.H. ed.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New developments in the IZG of metal oxide-metal eutectic composites

Description: Hartzell and Sekerka's numerical analysis of internal zone growth (IZG) has been used to interpret the problems of surface melting, difficult initial Rf-coupling, and heating controllability. By varying the parameters suggested by their analysis, solutions were found to all three problems as encountered in the IZG of Cr/sub 2/O/sub 3/--Mo eutectic composites. A new sample preparation technique was developed which allows Rf-coupling at room temperature and improved heating control.
Date: January 1, 1978
Creator: Holder, J. D. & Clark, G. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phase 2 of the Array Automated Assembly Task for the Low Cost Solar Array Project. Quarterly report 5, October 1-December 31, 1978

Description: Various top contact metal systems have been studied. Only Ti-Pd-Cu approaches baseline (Ti-Pd-Ag) quality, but this system shows a lack of long-term stability. Aluminum back surface field structures have been fabricated and thicknesses of p/sup +/ material of up to 7.0 microns have been achieved with open circuit voltages of 0.59V. A general purpose ultrasonic welder has been purchased and tests using various metal foils are under way. During fabrication of the demonstration module, several cel… more
Date: January 31, 1979
Creator: Campbell, R. B.; Page, D. J.; Rai-Choudhury, P.; Seman, E. J.; Hanes, M. H.; Rohatgi, A. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Processing yttrium-barium-copper oxide superconductor zero gravity using a double float zone surface

Description: The effects of processing YBa{sub 2}Cu{sub 3}O{sub x} (Y123) superconductor in the near-zero gravity (0g) environment provided by the NASA KC-135 airplane flying on parabolic trajectories were studied. A new sheet float zone furnace, designed for this study, enabled fast temperature ramps. Up to an 18-gram sample was processed with each parabola. Samples of Y123 were processed as bulk sheets, composites containing Ag and Pd, and films deposited on single crystal Si and MgO substrates. The 0g-pr… more
Date: April 1, 1997
Creator: Pettit, D. R.; Peterson, D. E.; Kubat-Martin, K. A.; Petrovic, J. J.; Sheinberg, H.; Coulter, Y. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pulsed CO sub 2 laser processing of thin ion-implanted silicon layers

Description: We show that extremely shallow ({approx lt} 800 {Angstrom}) melt depths can be easily obtained by irradiating a thin heavily doped silicon layer with a CO{sub 2} laser pulse. Since the absorption of the CO{sub 2} laser pulse is dominated by free-carrier transitions, the beam heating occurs primarily in the thin degenerately doped film. For CO{sub 2} pulse-energy densities exceeding a threshold value, surface melting occurs and the reflectivity of the incident laser pulse increases abruptly to a… more
Date: January 1, 1988
Creator: James, R.B. (Sandia National Labs., Livermore, CA (United States)) & Christie, W.H. (Oak Ridge National Lab., TN (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sequential Purification and Crystal Growth for the Production of Low Cost Silicon Substrates

Description: The objective of this program is to identify and develop low cost precessing for fabricating large grain size polycrystalline silicon substrates. Metallurgical grade silicon (MG-Si) is chosen as the starting material for sequential purification and crystal growth. Several purification techniques have been studied. They include (1) acid leaching with HCl, (2) physical separation of insoluble impurities, (3) reactive gas treatment of molten silicon, and (4) slagging using a mixed-oxide slag. In t… more
Date: August 1, 1980
Creator: Liaw, M.; D&#x27 & Aragona, F. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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