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(Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

Description: This report presents information concerning field procedures employed during the monitoring, well construction, well purging, sampling, and well logging at the Wright-Patterson Air Force Base. Activities were conducted in an effort to evaluate ground water contamination.
Date: October 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Indium phosphide/cadmium sulfide thin-film solar cells. Quarterly technical progress report No. 3, December 1979-April 1980

Description: Thin films (approx. 1 ..mu..m thick) and large grains (approx. 40 x 40 ..mu..m) of InP were epitaxially deposited on low-cost recrystallized CdS (RXCdS) substrates at 280/sup 0/C by planar reactive deposition. At 380/sup 0/C, a 0.4- to 1.0-..mu..m-thick In-Cd-S transition layer between the InP and the RXCdS degrades the quality of the InP epitaxy. However, p-type InP films were prepared at this temperature by Be-doping and capping the entire RXCdS substrate with InP. Large grains of CdTe (appro… more
Date: June 1, 1980
Creator: Zanio, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Creep of whisker-reinforced ceramics

Description: The results of high-temperature creep of various ceramic composites will be reviewed. In particular, creep results for Al{sub 2}O{sub 3} and Si{sub 3}N{sub 4} matrices reinforced with SiC whiskers will be emphasized. For a given temperature, stress and grain size, the creep rate of the Al{sub 2}O{sub 3} composite is usually lower than that of the ceramic matrix. In general, creep at low stresses occurs by grain boundary sliding accommodated by diffusion, whereas higher stresses lead to damage a… more
Date: January 1, 1991
Creator: Routbort, J.L; Goretta, K.C. (Argonne National Lab., IL (United States)); Dominguez-Rodriguez, A. & de Arellano-Lopez, A.R. (Seville Univ. (Spain))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thin film cadmium telluride solar cells. Final technical report, July 1, 1979-August 31, 1980

Description: Efforts during this program have been directed to the construction of apparatus for the chemical vapor deposition of cadmium telluride films, the selection and preparation of substrates, the deposition and characterization of cadmium telluride films, and the fabrication and characterization of solar cells. Cadmium telluride films have been deposited on a number of substrates by the direct combination of cadmium and tellurium on the substrate surface at 500/sup 0/C or higher at rates of up to 0.… more
Date: August 1, 1980
Creator: Chu, T. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AN INFORMATION STORAGE AND RETRIEVAL SYSTEM FOR IRRADIATION EFFECTS IN METALS

Description: An information storage and retrieval system (PIC) was developed, utilizing the IBM 7090 computer, for handling data pertaining to the effects of neutron irradiation on metals. The input includes a reference identification, an appropriate abstract or extract summarizing the article, code identification parameters analogous to those used by the ASM-SLA Literature Classification System, and special codes identifying relevant irradiation and testing parameters. The output contains the same data plu… more
Date: August 15, 1963
Creator: Bush, S. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Controlled cadmium telluride thin films for solar cells applications. First quarterly report, June 1, 1980-September 1, 1980

Description: During the first quarter of this renewed program, efforts have been extended mainly to set up a new ion beam sputtering system that would replace our existing r.f. sputtering system for the fabrication of doped CdTe thin films for solar cell applications. Preliminary attempts with this new equipment resulted in films with rather large grain size (0.8..mu.. - 1..mu..m) at an elevated substrate temperature. While this in itself is encouraging, certain difficulties were confronted in achieving the… more
Date: September 1, 1980
Creator: Das, M. B. & Krishnaswamy, S. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sequential purification and crystal growth for the production of low cost silicon substrates. Quarterly technical progress report No. 1, 15 September 1979-31 December 1979

Description: Over the past several years, Motorola's Materials Technology Laboratory (MTL), has been conducting several projects with goals directed at the production of high quality low cost silicon crystals. One of the projects which is being investigated is the direct purification of MG-Si. A unique characteristic of the approach used by this project is the use of a crystal puller to perform both purification and crystal growth. Sequential steps of purification were taken. By the completion of this … more
Date: February 1, 1980
Creator: Liaw, M.; Secco, F.; Ingle, B. & Down, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Failure of sheathed thermocouples due to thermal cycling

Description: Open circuit failures (up to 100%) in small-diameter thermocouples used in electrically heated nuclear fuel rod simulator prototypes during thermal cycling tests were investigated to determine the cause(s) of the failures. The experiments conducted to determine the relative effects of differential thermal expansion, wire size, grain size, and manufacturing technology are described. It was concluded that the large grain size and embrittlement which result from certain common manufacturing anneal… more
Date: March 1, 1982
Creator: Anderson, R.L. & Ludwig, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Austenitizing and Microstructure of a HT-9 Steel

Description: The effects of austenitizing temperatures and times on the microstructure of a 12Cr-1Mo-V-W steel are reported. Austenitizing temperatures covering the range of 900 to 1225/sup 0/C and times of 30 minutes to 100 hours were used. Equilibrium microstructures were difficult to obtain because delta ferrite initially present in the steel resists dissolution during austenitizing. 10 figures.
Date: January 1, 1983
Creator: Wilcox, R. C. & Chin, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thin film polycrystalline silicon solar cells

Description: During the present quarter efficiency of heterostructure solar cells has been increased from 13 to 13.7% for single crystal and from 10.3 to 11.2% for polysilicon. For polysilicon the improvements can be attributed to reductions in grid-area coverage and in reflection losses and for single crystal to a combination of reduction in grid-area coverage and increase in fill factor. The heterostructure cells in both cases were IT0/n-Si solar cells. Degradation in Sn0/sub 2//n-Si solar cells can be gr… more
Date: January 1, 1980
Creator: Ghosh, A. K.; Feng, T.; Eustace, D. J. & Maruska, H. P.
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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Automated array assembly task development of low-cost polysilicon solar cells. Quarterly technical report No. 2

Description: Three types of polysilicon materials were experimentally evaluated with Sensor Technology's standard production processing sequence during this reporting period. These materials include Wacker, Crystal Systems, and Exotic Materials polysilicon wafers. The average crystal grain size in the three polysilicon materials was obtained by statistically averaging the longest and shortest dimensions of each crystal grain in a set of random grain size measurements. An equation was derived to compute the … more
Date: December 1, 1979
Creator: Allison, K. L.; Jones, G. T.; Rhee, S. S. & Chitre, S. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental evaluation of a contact area evolution model

Description: Experiments designed to simulate boundary lubrication conditions during sheet forming were performed and evaluated. The results are compared to a model for contact area evolution caused by flattening of surface asperities. Microscopic observations and estimates of the area fraction in boundary contact agree reasonably well with the model. The effect of microstructural features on the accuracy of continuum models is also discussed. 8 refs., 15 figs.
Date: January 1, 1991
Creator: Korzekwa, D.A. (Los Alamos National Lab., NM (United States)) & Dawson, P.R. (Cornell Univ., Ithaca, NY (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Oxidation behavior of iron-chromium alloys at elevated temperatures: A reactive-element effect

Description: Oxidation tests were conducted on samples of Fe-25Cr, Fe-25Cr,-0.3-1.0Y, and Fe-25Cr-1Ce at temperatures of 700 to 1000{degrees}C and oxygen partial pressures of 1 to 20 atm for time periods of 19 to 160 h. In some tests, oxidized samples were quenched from test temperature to room temperature in {approximately}20 min to examine characteristics of the spallation scales. The results showed that the scales, even though of the same composition, spalled totally when developed on Fe-25Cr alloy, whil… more
Date: March 1, 1992
Creator: Park, J. H. & Natesan, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Creep strength of niobium alloys, Nb-1%Zr and PWC-11

Description: A study is being conducted at NASA Lewis Research Center to determine the feasibility of using a carbide particle strengthened Nb-1% Zr base alloy to meet the anticipated temperature and creep resistance requirements of proposed near term space power systems. In order to provide information to aid in the determination of the suitability of the PWC-11 alloy as an alternative to Nb-1% Zr in space power systems this study investigated (1) the long-time high-vacuum creep behavior of the PWC-11 mate… more
Date: January 1, 1990
Creator: Titran, R.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Emerging materials for solar cell applications. First quarter report, February 15-May 31, 1979

Description: Work to develop the theory controlling the electroplating of a compound semiconductor on a transparent, conductive substrate and to demonstrate operative solar cells using the approach is reported. The current program is divided essentially into three paralleled team efforts. The first effort centers on refining the electroplating process at Monosolar so thicker and more uniform layers of p- or n-type cadmium telluride can be plated on both In/sub 2/O/sub 3/:Sn- and Ni- coated substrates. 1 ..m… more
Date: June 15, 1979
Creator: Rod, R.L.; Shkedi, Z.; Bunshah, R. & Stafsudd, O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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JBK-75 microstructure specification recommendation. [Modified A-286]

Description: Since the ASTM-E-45 standard for microcleanliness is not applicable to superalloys like JBK-75 stainless steel (Modified A-286), Rocky Flats should adopt the Ladish microcleanliness standard (APML Cleanliness Classification of High Temperature Alloys Chart, 1971), as a guide for setting material acceptance specifications for JBK-75. Inclusion ratings of S-2, N-2, C-2, and M-2 should be acceptable. The microstructure should have a grain size of 5 or finer, but not smaller than 9, and microsegreg… more
Date: October 31, 1977
Creator: Brewer, A. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of data obtained from core tests in the design and operation of spent brine injection wells in geopressured or geothermal systems

Description: The effects of formation characteristics on injection well performance are reviewed. Use of data acquired from cores taken from injection horizons to predict injectivity is described. And methods for utilizing data from bench scale testing of brine and core samples to optimize injection well design are presented. Currently available methods and equipment provide data which enable the optimum design of injection wells through analysis of cores taken from injection zones. These methods also provi… more
Date: March 1, 1980
Creator: Jorda, R.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microstructural influence on the work hardening of aluminum-lithium alloy 2090 at cryogenic temperatures

Description: Previous studies indicate that the work hardening characteristics of a Vintage III 2090-T81 12.7-mm (0.5-in.) plate is highly dependent on the through-thickness position. This dependency has been linked to two distinctly different microstructures existing as laminates within the plate. An investigation of the two microstructures by both optical and transmission electron microscopy reveal a difference in the distribution of grains and subgrains. It is believed that these factors affect the work … more
Date: June 1991
Creator: Chu, D.; Tseng, C. T. & Morris, J. W., Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cluster assembly of hierarchical nanostructures

Description: In the past few years, atom clusters with diameters in the range of 2--20 nm of a variety of materials, including both metals and ceramics, have been synthesized by evaporation and condensation in high-purity gases and subsequently consolidated in situ under ultrahigh vacuum conditions to create nanophase materials. These new utlrafine-grained materials have properties that are often significantly different and considerably improved relative to those of their coarser-grained counterparts owing … more
Date: February 1, 1992
Creator: Siegel, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sintering of bulk high- Tc superconductors: Y-Ba-Cu-O

Description: Sintering of bulk YBa{sub 2}Cu{sub 3}O{sub x} (123) samples has been conducted from 850 to 1010{degrees}C in oxygen partial pressures (P{sub O2}) of 2.5 {times} 10{sup 2} to 10{sup 5} Pa. The final grain sizes of the samples were controlled by selective use of (1) liquid phases and (2) partial decomposition of the 123 phase by sintering in a P{sub O2} that was lower than the minimum needed for 123 stability. In nearly fully dense samples, it was found that the grain size could range from about … more
Date: May 1, 1992
Creator: Goretta, K.C.; Chen, N.; Lanagan, M.T.; Wu, W.; Singh, J.P.; Olson, R.A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fatigue-crack propagation in aluminum-lithium alloys processed by power and ingot metallurgy

Description: Fatigue-crack propagation behavior in powder-metallurgy (P/M) aluminum-lithium alloys, namely, mechanically-alloyed (MA) Al-4.0Mg-1.5Li-1.1C-0.80{sub 2} (Inco 905-XL) and rapid-solidification-processed (RSP) Al-2.6Li-1.0Cu-0.5Mg-0.5Zr (Allied 644-B) extrusions, has been studied, and results compared with data on an equivalent ingot-metallurgy (I/M) Al-Li alloy, 2090-T81 plate. Fatigue-crack growth resistance of the RSP Al-Li alloy is found to be comparable to the I/M Al-Li alloy; in contrast, c… more
Date: April 1, 1990
Creator: Venkateswara Rao, K.T.; Ritchie, R.O. (Lawrence Berkeley Lab., CA (United States)); Kim, N.J. (Pohang Inst. of Science and Technology (Korea, Republic of)) & Pizzo, P.P. (San Jose State Univ., CA (United States))
Item Type: Refine your search to only Article
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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Emerging materials for solar cell applications: electrodeposited CdTe. Final report, February 14, 1979-February 14, 1980

Description: Thin film gold/polycrystalline cadmium telluride Schottky solar cells made by electrodepositing the semiconductor on an ITO-coated glass substrate serving also as an ohmic contact demonstrated an internal efficiency of 4% over 2 mm/sup 2/ areas. During the year being reported upon, Monosolar devoted mator attention to refining the electroplating process and determining the parameters governing CdTe film stoichiometry, grain size, substrate adhesion, and quality. UCLA acting as a Monosolar sub-c… more
Date: May 15, 1980
Creator: Rod, R.L.; Bunshah, R.; Stafsudd, O.; Basol, B.M. & Nath, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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