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Existence of fcc TiCr/sub 1/ /sub 8/H/sub 5/ /sub 3/

Description: Originally an orthorhombic structure was assigned to the non-stoichiometric hydride TiCr/sub 1/ /sub 8/H/sub 3/ /sub 6/. Recent neutron and x-ray diffraction data indicated, however, that an alternate interpretation was possible, i.e. the solid consists of two hydride phases, an ..cap alpha..' Laves phase having a composition of TiCr/sub 1/ /sub 8/H/sub 2/ /sub 8/ and an fcc phase with a much higher hydrogen content. This proved to be the case and it has been determined that the high concentrat… more
Date: February 1, 1982
Creator: Johnson, J. R.; Reilly, J. J.; Reidinger, F.; Corliss, L. M. & Hastings, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characteristics of chars produced by pyrolysis following rapid heating of pulverized coal. [104 references]

Description: A 5.08-cm id pyrolysis furnace has been used to study pyrolysis following rapid heating of size graded pulverized coal particles as a function of isothermal pyrolysis time (0.018 to 1.025 second), particle size (50 to 181 ..mu..m), and parent coal (three lignites). The following experimental conditions were kept constant: Coal feed rate approximately equal to 0.5 g/min; volumetric flow rate of nitrogen temperature = 808/sup 0/C, and pressure = atmospheric. Under these conditions the heating rat… more
Date: February 1, 1977
Creator: Nsakala, N.; Walker, Jr., P. L. & Essenhigh, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel nanodispersed coal liquefaction catalysts: Molecular design via microemulsion-based synthesis

Description: The objective of this project is to pursue the development of highly dispersed and inexpensive catalysts for improved coal solubilization and upgrading of coal liquids. A novel study of the synthesis of liquefaction catalysts of nanometer size will be carried out. It is based on the molecular design of reverse micelles (microemulsions). These surfactant-stabilized, metal-bearing microdrops offer unique opportunities for synthesizing very small particles by providing a cage-like effects that lim… more
Date: February 1, 1991
Creator: Osseo-Asare, K. & Radovic, L.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Applications of circularly polarized photons at the ALS with a bend magnet source

Description: The purpose of this workshop is to focus attention on, and to stimulate the scientific exploitation of, the natural polarization properties of bend-magnet synchrotron radiation at the ALS -- for research in biology, materials science, physics, and chemistry. The topics include: The Advanced Light Source; Magnetic Circular Dichroism and Differential Scattering on Biomolecules; Tests of Fundamental Symmetries; High {Tc} Superconductivity; Photoemission from Magnetic and Non-magnetic Solids; Studi… more
Date: February 1, 1992
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure of tris(trimethylsilylcyclopentadienyl)uranium(III), ((CH/sub 3/)/sub 3/SiC/sub 5/H/sub 43/U. [Tris(trimethylsilylcyclopentadienyl)uranium]

Description: Crystals of ((CH/sub 3/)/sub 3/SiC/sub 5/H/sub 4/)/sub 3/U are orthorhombic, Pbca, with a = 22.630(8), b = 29.177(10) and c = 8.428(3) A at 23/sup 0/C. For Z = 8 the calculated density is 1.551 g/cm/sup 3/. The structure was refined by full-matrix least-squares to a conventional R factor of 0.041 (2251 data, F/sup 2/ > 2 sigma(F/sup 2/)). The uranium atom is bonded to the three cyclopentadienyl rings in a pentahapto fashion and is in the plane of the ring centroids. The U to ring distances are … more
Date: February 1, 1986
Creator: Brennan, J.; Andersen, R. A. & Zalkin, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A comprehensive review of the XRD data of the primary and secondary phases present in the BSCCO superconductor system

Description: X-ray powder patterns for the phases in the CaO-SrO-PbO ternary system, along with the corresponding crystal structures, were obtained from the literature and from the Powder Diffraction File (PDF). Available X-ray diffraction (XRD) patterns were compared with each other and, when possible, with a calculated pattern for each phase, yielding a recommended reference pattern. The simulated powder patterns presented here deal with the phases found within the (Ca,Sr){sub 2}PbO{sub 4} solid solution … more
Date: February 1, 1992
Creator: Reardon, B.J. & Hubbard, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surprising Coordination Geometry Differences in Ce(IV)- and Pu(IV)-Maltol Complexes

Description: As part of a study to characterize the detailed coordination behavior of Pu(IV), single crystal X-ray diffraction structures have been determined for Pu(IV) and Ce(IV) complexes with the naturally-occurring ligand maltol (3-hydroxy-2-methyl-pyran-4-one) and its derivative bromomaltol (5-bromo-3-hydroxy-2-methyl-pyran-4-one). Although Ce(IV) is generally accepted as a structural analog for Pu(IV), and the maltol complexes of these two metals are isostructural, the corresponding bromomaltol compl… more
Date: February 12, 2008
Creator: Laboratory, Lawrence Berkeley National; Raymond, Kenneth; Szigethy, Geza; Xu, Jide; Gorden, Anne E.V.; Teat, Simon J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A laboratory based system for Laue micro x-ray diffraction

Description: A laboratory diffraction system capable of illuminating individual grains in a polycrystalline matrix is described. Using a microfocus x-ray source equipped with a tungsten anode and prefigured monocapillary optic, a micro-x-ray diffraction system with a 10 mum beam was developed. The beam profile generated by the ellipsoidal capillary was determined using the"knife edge" approach. Measurement of the capillary performance, indicated a beam divergence of 14 mrad and a useable energy ba… more
Date: February 28, 2007
Creator: Source, Advanced Light; Tamura, Nobumichi; Lynch, P. A.; Stevenson, A. W.; Liang, D.; Parry, D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cerocene Revisited: The Electronic Structure of and Interconversion Between Ce2(C8H8)3 and Ce(C8H8)2

Description: New synthetic procedures for the preparation of Ce(cot)2, cerocene, from [Li(thf)4][Ce(cot)2], and Ce2(cot)3 in high yield and purity are reported. Heating solid Ce(cot)2 yields Ce2(cot)3 and COT while heating Ce2(cot)3 with an excess of COT in C6D6 to 65oC over four months yields Ce(cot)2. The solid state magnetic susceptibility of these three organocerium compounds shows that Ce(cot)2 behaves as a TIP (temperature independent paramagnet) over the temperature range of 5-300 K, while that of Ce… more
Date: February 2, 2009
Creator: Walter, Marc D.; Booth, Corwin H.; Lukens, Wayne W. & Andersen, Richard A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spectroscopic imaging, diffraction, and holography with x-ray photoemission

Description: X-ray probes are capable of determining the spatial structure of an atom in a specific chemical state, over length scales from about a micron all the way down to atomic resolution. Examples of these probes include photoemission microscopy, energy-dependent photoemission diffraction, photoelectron holography, and X-ray absorption microspectroscopy. Although the method of image formation, chemical-state sensitivity, and length scales can be very different, these X-ray techniques share a common go… more
Date: February 1, 1992
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure and shear response of lipid monolayers

Description: We have been studying lipid monolayers both on the surface of water and after transfer to solid substrates. On the surface of water, we have determined in detail the structure of heneicosanoic acid monolayers along a high-pressure isobar, and correlated this information with viscosity data. We have also determined the effect of ions in the subphase on acid monolayer structure (as a function of pH). We have studied capillary waves on monolayer-covered water surfaces, and we find that these monol… more
Date: February 1, 1992
Creator: Dutta, P. & Ketterson, J.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of saponite and saponite/sepiolite fluids for geothermal drilling

Description: The rheology and other properties of drilling fluids containing saponite and a saponite-sepiolite mixture as the main vicosifier have been systematically evaluated in the temperature range of 300-600{degree}F under appropriate confining pressures up to 16,000 psi. Saponite represents the magnesium analog of the clay mineral montmorillonite, which is the main constituent in conventional bentonite-based fluids. The fluid with 6% saponite exhibits a prominent viscosity enhancement at temperatures … more
Date: February 1, 1991
Creator: Guven, N.; Panfil, D. J. & Carney, L. L. (Texas Tech Univ., Lubbock, TX (USA). Dept. of Geosciences)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Identification of the mineral phases responsible for cementation of Lurgi spent oil shale

Description: The purpose of this study is to investigate the mineralogical character of the cements that are responsible for the increased strength of the spent oil shale. Several techniques to identify the nature of the cementing agents have been used in this study. X-ray diffraction was used to identify mineral dissolution and formation; scanning electron microscopy (SEM) was used to observe the cementing agents; energy dispersive X-ray analysis (EDXA) was used to provide information on the elemental comp… more
Date: February 1, 1991
Creator: Brown, M.; Huntington, G. & Brown, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of the corrosion behavior of cooling coil material in a simulated concrete environment

Description: Pitting corrosion of the cooling coils embedded in the concrete roof of the waste tanks is one of the suspected causes of the recent cooling coil failures. Cyclic polarization tests were conducted to predict the threshold chloride level above which pitting would initiate. The threshold chloride level was determined to be 9000 ppM. Although these tests predict the electrochemical or corrosion behavior of the metal, they may not predict the severity of attack. Further tests which investigate the … more
Date: February 1, 1993
Creator: Wiersma, B.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Non-H[sub 2]Se, ultra-thin CIS devices. [CuInSe[sub 2]]

Description: This report describes work done during Phase I of a 3-phase, cost- shared contract. Objective of the subcontract is to demonstrate 12% total-area efficiency copper indium diselenide (CIS) solar cells and 50-W CIS modules average at least 8 W/ft[sup 2] in the third year. At the end of Phase I, EPV delivered to NREL a 1.1 cm[sup 2] CIS cell with an active area efficiency of 10.5%. the corresponding total-area efficiency is 7.9%.
Date: February 1, 1993
Creator: Delahoy, A.E.; Britt, J. & Kiss, Z. (Energy Photovoltaics, Inc., Princeton, NJ (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of air distributor plates from atmospheric fluidized combustors: Rivesville and Alexandria

Description: Samples of perforated Type 310 stainless steel plates that were used as the air distributor grids for the Rivesville, West Virginia, and Alexandria, Virginia, atmospheric fluidized-bed combustors together with unexposed plate material were examined to determine the cause of cracking of the Rivesville plate. Intergranular cracks in the Rivesville plate are associated with massive sigma phase precipitates on grain boundaries. Both plates buckled during service, probably because of thermal stresse… more
Date: February 1, 1979
Creator: King, R.T.; Gray, R.J.; Leitnaker, J.M.; Ratcliff, L.T. & Houck, C.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Predicting stress corrosion crackig in welded steel based on residual stress measurements

Description: Residual stress measurements were made on a welded HP-9-4-20 steel test coupon to determine the potential of residual stress for producing stress corrosion cracking. X-ray diffraction and strain gauge rosettes were used to make the measurements. The results indicated that, under the conditions specified, the stress intensity produced by residual stress was one-fourth that required to produce stress corrosion cracking.
Date: February 1, 1979
Creator: Brewer, D.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Special core analyses and relative permeability measurement on Almond formation reservoir rocks

Description: This report describes the results from special core analyses and relative permeability measurements conducted on samples of rock from the Almond Formation in Greater Green River Basin of southwestern Wyoming. The core was from Arch Unit Well 121 of Patrick Draw field. Samples were taken from the 4,950 to 4,965 ft depth interval. Thin section evaluation, X-ray diffraction, routine permeability and porosity, capillary pressure and wettability tests were performed to characterize the samples. Flui… more
Date: February 1, 1993
Creator: Maloney, D.; Doggett, K. & Brinkmeyer, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In situ studies of zeolite syntheses using powder diffraction methods: Crystallization of ``instant zeolite A`` powder and CoAPO-5

Description: A series of hydrothermal zeolite synthesis were performed on a powder diffractometer using synchrotron radiation and a position sensitive detector. Direct observation of the induction period (nucleation stage), crystallization and transformation of zeolite 4A (Na-LTA) was possible due to the intense X-ray beam which allows fast data collection. High pressure experiments were performed, allowing observation of hydrothermal synthesis of a cobalt substituted AlPO{sub 4}-zeolite, CoAPO-5, up to 165… more
Date: February 1, 1994
Creator: Norby, P.; Christensen, A. N. & Hanson, J. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Identification of the mineral phases responsible for cementation of Lurgi spent oil shale

Description: The purpose of this study is to investigate the mineralogical character of the cements that are responsible for the increased strength of the spent oil shale. Several techniques to identify the nature of the cementing agents have been used in this study. X-ray diffraction was used to identify mineral dissolution and formation; scanning electron microscopy (SEM) was used to observe the cementing agents; energy dispersive X-ray analysis (EDXA) was used to provide information on the elemental comp… more
Date: February 1, 1991
Creator: Brown, M.; Huntington, G. & Brown, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Local texture and grain boundary misorientations in high T{sub C} oxide superconductors

Description: The orientations of hundreds of contiguous grains in high J{sub C} TlBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} deposits and (Bi, Pb){sub 2} Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y} powder-in-tube tapes have been determined from electron back scatter diffraction patterns (EBSP). The misorientation angles and axes of rotation (angle/axis pairs) for grain boundaries connecting these grains were calculated. For both materials the population of low angle boundaries was found to be much larger than expected fro… more
Date: February 1, 1995
Creator: Kroeger, D. M.; Goyal, A.; Specht, E. D.; Tkaczyk, J. E.; Sutliff, J.; DeLuca, J. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Applications of circularly polarized photons at the ALS with a bend magnet source

Description: The purpose of this workshop is to focus attention on, and to stimulate the scientific exploitation of, the natural polarization properties of bend-magnet synchrotron radiation at the ALS -- for research in biology, materials science, physics, and chemistry. The topics include: The Advanced Light Source; Magnetic Circular Dichroism and Differential Scattering on Biomolecules; Tests of Fundamental Symmetries; High {Tc} Superconductivity; Photoemission from Magnetic and Non-magnetic Solids; Studi… more
Date: February 1, 1992
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Structure and shear response of lipid monolayers. Progress report, July 1, 1989--June 31, 1990

Description: Organic monolayers and multilayers are both scientifically fascinating and technologically promising; they are, however, both complex systems and relatively inaccessible to experimental probes. In this Progress Report, we describe our X-ray diffraction studies, which have given us substantial new information about the structures and phase transitions in monolayers on the surface of water; our use of these monolayers as a unique probe of the dynamics of wetting and spreading; and our studies of … more
Date: February 1, 1990
Creator: Dutta, P. & Ketterson, J. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Special core analyses and relative permeability measurement on Almond formation reservoir rocks

Description: This report describes the results from special core analyses and relative permeability measurements conducted on samples of rock from the Almond Formation in Greater Green River Basin of southwestern Wyoming. The core was from Arch Unit Well 121 of Patrick Draw field. Samples were taken from the 4,950 to 4,965 ft depth interval. Thin section evaluation, X-ray diffraction, routine permeability and porosity, capillary pressure and wettability tests were performed to characterize the samples. Flui… more
Date: February 1, 1993
Creator: Maloney, D.; Doggett, K. & Brinkmeyer, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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