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Low-Cost Solar Array Project. Progress report 14, August 1979-December 1979 and proceedings of the 14th Project Integration Meeting

Description: Progress made by the Low-Cost Solar Array Project during the period August through November 1979, is described. Progress on project analysis and integration; technology development in silicon material, large-area sheet silicon, and encapsulation; production process and equipment development; engineering, and operations, and the steps taken to integrate these efforts are detailed. A report on the Project Integration Meeting held December 5-6, 1979, including copies of the visual materials used, … more
Date: January 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low cost Czochralski crystal growing technology: near term implementation of the flat plate photovoltaic cost reduction of the Low Cost Solar Array Project. Fifth quarterly progress report, April 1-June 30, 1980

Description: During this reporting period, the primary activity has been to develop microprocessor control of the crystal growth process and to develop and demonstrate the accelerated crystal growth program. Accelerated recharging of the quartz crucible by the RF melting of polycrystalline silicon feed rods was deemphasized by JPL primarily due to the unavailability of suitable quality feed rods at an effective economical price. The development of the cold crucible program as an alternative method of crucib… more
Date: January 1, 1980
Creator: Roberts, E. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Damage nucleation in Si during ion irradiation

Description: Damage nucleation in single crystals of silicon during ion irradiation is investigated. Experimental results and mechanisms for damage nucleation during both room and liquid nitrogen temperature irradiation with different mass ions are discussed. It is shown that the accumulation of damage during room temperature irradiation depends on the rate of implantation. These dose rate effects are found to decrease in magnitude as the mass of the ions is increased. The significance of dose rate effects … more
Date: January 1, 1984
Creator: Holland, O.W.; Fathy, D. & Narayan, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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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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Optical design and performance of the X25 hybrid wiggler beam line at the NSLS

Description: The X25 beam line at the National Synchrotron Light Source (NSLS) began full-power commissioning in 1990. It extracts radiation from a 27 pole hybrid wiggler, which produces up to 1.8 kW of total power with a peak horizontal density of 450 W/mrad and critical energy of 4.6 keV. The design and performance of the beam line optics are described, in particular the cooling of the first monochromator crystal. 28 refs., 5 figs.
Date: January 1, 1991
Creator: Berman, L. E.; Hastings, J. B.; Oversluizen, T. & Woodle, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling studies on the precipitation of Kr after implantation into metals

Description: A rate-theory approach is applied to interpreting observations on the precipitation of Kr injected into Ni at temperatures between 25 and 560/degree/C. At temperatures of 400/degree/C or higher, the implanted Kr precipitates evolve into a bi-modal size distribution containing small solid precipitates and an additional population of larger, faceted bubbles. The calculations explore the dependence of the observed bi-modal distribution on the maximum size of the solid Kr precipitates and the effec… more
Date: February 1, 1988
Creator: Rest, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electrochemical photovoltaic cells. Project 65039 quarterly technical progress report, April 15-July 31, 1980

Description: Liquid-junction photoelectrochemical cells can be used either for the direct conversion of solar energy to electricity or to generate stored chemical species available for later electrochemical discharge. The objectives of this program are to identify experimental approaches for electrochemical photovoltaic cells that not only show promise of high power-conversion efficiencies but also have the potential to achieve long life and the capacity for energy storage. The work is organized as follows:… more
Date: September 1, 1980
Creator: Ang, P. G.P. & Sammells, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ceramic technology for Advanced Heat Engines Project

Description: Significant accomplishments in fabricating ceramic components for advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and database and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine… more
Date: July 1, 1991
Creator: Johnson, D. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Equation of state of solid neon from x-ray diffraction measurements to 110 GPa

Description: This paper briefly discusses the pressure-volume properties of condensed neon. X-ray diffraction techniques are used to determine solid neon equation of state and crystal structure. 16 refs., 2 figs. (LSP)
Date: January 1, 1987
Creator: Hemley, R. J.; Jephcoat, A. P.; Zha, C. S.; Mao, H. K.; Finger, L. W. & Cox, D. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure of NH/sub 3/ on Ni(111)

Description: In a recent study of the adsorption of NH/sub 3/ on NI(111) at T approx. 190 K using angle resolved UPS, it was concluded that NH/sub 3/ is molecularly adsorbed, and is bonded to the surface via the N atom with the H atoms oriented away from the surface. To study the bonding configuration using a direct and independent technique, we have examined NH/sub 3/ on Ni(111) using the electron stimulated desorption ion angular distribution (ESDIAD) method, coupled with temperature programmed desorption… more
Date: January 1, 1980
Creator: Madey, T. E.; Houston, J. E.; Seabury, C. W. & Rhodin, T. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Silicon ingot casting: Heat Exchanger Method (HEM)/multi-wire slicing: Fixed Abrasive Slicing Technique (FAST), Phase IV. Quarterly progress report No. 2, April 1, 1980-June 30, 1980

Description: Silicon ingot size cast by HEM has been extended to 34 cm x 34 cm x 10 cm. A 20 kg ingot has been solidified at 3 kg/hr with no crucible attachment or ingot cracking problems. Another ingot of 26 kg weight has also been solidified. The heat treatment used to develop a graded structure caused cracking on the inside surface of the first large crucibles. The thermal conditions were altered to minimize high gradients and the cracking was eliminated. A high degree of single crystallinity has been ma… more
Date: August 1, 1980
Creator: Schmid, F.; Khattak, C.P. & Basaran, M.
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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Techniques and processes for the measurement of the resonances of small single crystals

Description: The mechanical resonances of small oriented single crystals of materials of interest to basic science and engineering can be used to determine all the elastic moduli and the ultrasonic attenuation of these materials. To measure the resonances of the samples without introducing the resonances of the measuring system requires that the transducers be non-resonant at the frequencies of interest, and that they be well isolated from their mounts. However, for samples near 1 mm in the largest dimensio… more
Date: January 1, 1991
Creator: Migliori, A.; Stekel, A.; Sarrao, J.L.; Visscher, W.M.; Bell, T. & Lei, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Array automated assembly: Phase 2. Quarterly report

Description: An analysis was made of cost trade-offs for shaping modified square wafers from cylindrical crystals. For reasonably expectable silicon and sheet costs, the optimum shape will be nearer a circle than a square. Tests were conducted of the effectiveness of texture etching for removal of surface damage on sawed wafers. Four glass systems have survived preliminary screening tests for use as edge masking dielectrics. These include beta-spodumen, MgO-Al/sub 2/O/sub 3/ borosilicate, baria and titania … more
Date: February 1, 1978
Creator: Taylor, W.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mushy-zone model with an exact solution

Description: In this paper we propose a very simple model of a mushy zone which admits of an explicit solution. To our knowledge, it is the only instance where an actual observation of the mushy zone width and structure is used as a partial basis for the model definition. The model rests upon two unknown parameters. The first determines the relation between the equilibrium temperature gradient and the mushy zone width. The second depends upon the dendritic structure in the mushy zone, and is related to the … more
Date: April 1, 1982
Creator: Solomon, A. D.; Wilson, D. G. & Alexiades, V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991

Description: The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. … more
Date: April 1, 1992
Creator: Judkins, R.R. & Cole, N.C. (comps.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Time-Resolved Doubly Bent Crystal X-Ray Spectrometer

Description: X-ray spectroscopy is an essential tool in high temperature plasma research. We describe a time-resolved x-ray spectrometer suitable for measuring spectra in harsh environments common to many very high energy density laboratory plasma sources. The spectrometer consisted of a doubly curved Si(111) crystal diffraction element, a WL-1201 (ZnO:Ga) phosphor, a coherent fiber optic array, and two visible streak cameras. The spectrometer design described here has a minimum time resolution of 1.3 ns wi… more
Date: January 1, 1988
Creator: Hockaday, M. P.; Wilke, M. D.; Blake, R. L.; Vaninetti, J.; Gray, N. T. & Nedrow, P. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of strain birefringence and wavefront distortion in 001 plates of KD sub 2 PO sub 4

Description: When 001 plates of KD{sub 2}PO{sub 4} (KD*P) are used in Pockels cells, strain induced refractive index variations result in beam depolarization and transmitted wavefront distortion. The depolarization is determined by the induced birefringence while the wavefront distortion is controlled by the average index shift. Here we show that the birefringence is determined by the shear stress in the xy-plane of the crystal while the average index shift depends only on the normal stresses. Furthermore, … more
Date: August 26, 1991
Creator: De Yoreo, J. J. & Woods, B. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spectral weight changes at the superconducting transition of Bi sub 2 Sr sub 2 CaCu sub 2 O sub 8+. delta

Description: An overview of our gap studies in high-{Tc} superconductors is presented for the workshop on Fermiology of high-{Tc}'s. The work is centered on the study of single crystal Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}. In a conventional BCS superconductor, a superconducting gap {Delta} is formed when the near Fermi edge electrons condense to form Cooper pairs at low temperatures. As the material goes superconducting the density of states is modified such that the spectral intensity in the regio… more
Date: January 1, 1991
Creator: Dessau, D. S.; Shen, Z. X.; Wells, B. O.; Spicer, W. E. (Stanford Univ., CA (United States). Stanford Electronics Labs.) & Arko, A. J. (Los Alamos National Lab., NM (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Muon Spin-Rotation Study on Magnetite

Description: Muon spin-rotation (..mu..SR) results on synthetic single crystals of magnetite (Fe/sub 3/O/sub 4/) support the idea of muon bond formation in oxides. The anomaly in the temperature dependence of the ..mu..SR signal observed in Fe/sub 3/O/sub 4/ may be attributed to the existence of molecular polarons in the Verwey transition-temperature region.
Date: January 1, 1982
Creator: Boekema, C.; Brabers, V. A. M.; Denison, A. B.; Heffner, R. H.; Hutson, R. L.; Leon, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Continuous Czochralski growth. Silicon sheet growth development of the large area silicon sheet task of the Low Cost Silicon Solar Array Project. First quarterly progress report, October--December 1977

Description: The development of equipment and processes to produce single crystal solar silicon by a continuous Czochralski method was studied. ''Continuous'' is defined as the ability to produce 100 kilograms of crystal from only one melt container. The equipment to be used is a Hamco CG2000 Production Crystal Grower. Certain modifications will be made to the grower to enable periodic replenishment of silicon into the crucible and removal of grown crystals. The crystal grower was constr… more
Date: December 31, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrogenation of CO and CO/sub 2/ on clean rhodium and iron foils. Correlations of reactivities and surface compositions

Description: An experimental arrangement consisting of an ultrahigh vacuum bell jar equipped with an internal sample isolation cell was used to investigate the hydrogenation of CO over Fe and Rh surfaces. This apparatus permitted both UHV surface characterization (Auger electron spectroscopy, low-energy electron diffraction) and high pressure (1-20 atm) catalytic reactions to be carried out. Small surface area (approximately 1 cm/sup 2/) metal samples, both single crystals and polycrystalline foils, were us… more
Date: December 16, 1977
Creator: Dwyer, D.; Yoshida, K. & Somorjai, G.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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