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Hydrogeochemical and stream sediment reconnaissance basic data for Las Cruces quadrangle, New Mexico

Description: Field and laboratory data are presented for 501 water samples and 1817 sediment samples from the Las Cruces Quadrangle, New Mexico. The samples were collected and uranium analysis performed by Los Alamos National Laboratory; multielement analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee.
Date: August 31, 1981
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thin film battery/fuel cell power generating system. Final report, Task E-4, April 1976-April 1978

Description: A two-year researth program to design and demonstrate the technical feasibility of a high-temperature solid-electrolyte fuel cell is described in detail. A rare-earth chromite, in particular, La /sub 95/Mg /sub 05/Cr /sub 75/Al /sub 25/0/sub 3/ was identified, synthesized by RF-sputtering tested for resistivity, thermal expansion and inertness in contact with yttria-stabilized zirconia, and was found promising as a candidate interconnection material. Films of these interconnection materials hav… more
Date: March 31, 1978
Creator: Feduska, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron scattering studies of magnetism in the high-Tc materials

Description: In this paper, I shall attempt to review what has been learned about magnetism in the high-{Tc} family of compounds using neutron scattering techniques. Whether or not it is true that magnetic effects are involved in an essential way in the mechanism for superconductivity in these materials (a point which has not yet been firmly established), they offer fascinating examples for the study of magnetism for its own sake, being realizations of spin {1/2} 2D quantum antiferromagnets. Further, the ra… more
Date: December 31, 1990
Creator: Sinha, S. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vacancy related defects in thin film Pb(ZrTi)O{sub 3} materials

Description: Positron annihilation techniques have been applied to characterize vacancy-related defects in ferroelectric thin film structures. Variable energy positron beam measurements were carried out on doped and undoped Pb(ZrTi)O{sub 3} (PZT) samples subjected to different post-deposition cool down and anneal conditions. The PZT was deposited by sol-gel with either with platinum or RuO{sub 2} electrodes, or by laser ablation with La{sub 0.5}Sr{sub 0.5}CoO{sub 3} electrodes. The RuO{sub 2} and La{sub 0.5… more
Date: December 31, 1994
Creator: Krishnan, A.; Keeble, D. J.; Ramesh, R.; Warren, W. L.; Tuttle, B. A.; Pfeffer, R. L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transient studies of low temperature catalysts for methane conversion. Quarterly technical progress report, June 30, 1993--September 30, 1993

Description: This report summarizes studies on the oxidative coupling of methane on metallo oxide catalysts. A previous report summarized the results on the partial oxidation of methane on Li promoted VPO{sub 4} catalysts and the role of the Li promotion on increasing formaldehyde selectivity. The results of such study have been summarized in a paper submitted for publication. Given the relatively low conversion of methane and the low formaldehyde selectivity, it was decided to continue studying the oxidati… more
Date: December 31, 1993
Creator: Wolf, E. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aspects of macroscopic phase separation and interstitial oxygen ordering in oxygen doped La{sub 2}CuO{sub 4+{delta}}

Description: NMR and neutron diffraction measurements reveal that macroscopic phase separation and the tetragonal to orthorhombic (TO) structural phase coincide at two distinct points in the temperature-doping phase plot for oxygen doped La{sub 2}CuO{sub 4+{delta}}. Thus the TO phase line coincides with the phase separation line. This is evidence that the macroscopic phase separation is inhibited in the tetragonal phase. We propose that the interstitial oxygen has higher mobility in the orthorhombic phase a… more
Date: December 31, 1994
Creator: Hammel, P. C.; Fisk, Z.; Statt, B. W.; Chou, F. C.; Johnston, D. C.; Cheong, S. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrared properties of high T{sub c} superconductors

Description: Over the past several years a coherent phenomenology of the high {Tc} cuprate superconductors has begun to emerge. Infrared measurements have contributed several important ingredients to this picture including: (1) the inference of a scattering rate that is linear in frequency for {omega}>T, and of order {omega}, (2) a characteristic energy scale in the superconducting state of 500 cm{sup {minus}1} (60 meV), which can be interpreted as a superconducting pair excitation threshold or energy gap, … more
Date: December 31, 1991
Creator: Schlesinger, Z.; Rotter, L. D.; Collins, R. T.; Holtzberg, F.; Feild, C.; Welp, U. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Luminescent and electroactive labels for DNA sequencing and mapping

Description: New labels for DNA based on metalloorganic compounds that are either electrochemically active or have long-lived luminescent excited states have been prepared. A derivative of the macrocyclic chelating agent, 1,4,7,10-tetracyclododecane-1,4,7,10-tetraacetic acid (DOTA) was used to attach the lanthanide [Ln(III)] ion to oligonucleotides. This ligand proved stable providing kinetically inert complexes with such metal ions.
Date: December 31, 1994
Creator: Brown, G. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Selective methane oxidation over promoted oxide catalysts

Description: Objective was to selectively oxidize methane to C{sub 2} hydrocarbons and to oxygenates, in particular formaldehyde and methanol, in high space time yields under relatively mild reaction conditions. Results in this document are reported under the headings: methane oxidation over silica, methane oxidation over Sr/La{sub 2}O{sub 3} catalysts, and oxidative coupling of methane over sulfate-doped Sr/La{sub 2}O{sub 3} catalysts. 24 refs, 10 figs, 4 tabs.
Date: December 31, 1993
Creator: Klier, K. & Herman, R. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Aging effects in palladium and LaNi{sub 4.25}Al{sub 0.75} tritides

Description: Palladium and LaNi{sub 5-x}Al{sub x} (x=0.30, 0.75, 0.85), which form reversible hydrides, are used for tritium processing and storage in the Savannah River Site (SRS) tritium facilities. As part of a program to develop technology based on the use of reversible metal hydrides for tritium processing and storage, the effects of aging on the thermodynamic behavior of palladium and LaNi{sub 4.25}Al{sub 0. 75} tritides are under investigation. During aging, the {sup 3}He tritium decay product remain… more
Date: December 31, 1991
Creator: Nobile, A.; Wermer, J. R. & Walters, R. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cerium Compounds as Scintillators

Description: Stoichiometric Ce-materials with negligible Ce-Ce interactions should have superior scintillator properties. We present two materials: CeF{sub 3} and Ce{sub x}La{sub 1-x}P{sub 5}O{sub 14}. While cerium trifluoride is a known scintillator, pentaphosphate is of a limited usefulness, except as a remarkable model material. We show that quenching in fluoride is responsible for loss of 50% of the light output and is the cause of the, so-called, ultra fast component (2 ns). Light output of fluoride (a… more
Date: December 31, 1991
Creator: Wojtowicz, A. J.; Berman, E.; Koepke, C. & Lempicki, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced Hydride Laboratory

Description: The Replacement Tritium Facility (RTF) is a $140 million reservoir loading and unloading facility using state-of-the-art technology, scheduled for completion in 1990 and startup in 1991. In the RTF, metal hydride technology will be used to store, separate, purify, pump, and compress hydrogen isotopes. In support of the RTF, a $3.2 million ``cold`` process demonstration facility began operation in November, 1987. The purpose of the Advanced Hydride Laboratory (AHL) is to demonstrate the RFT`s me… more
Date: December 31, 1989
Creator: Horen, A. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Lattice instabilities and structural phase transformations in La{sub 2}CuO{sub 4} superconductors and insulators

Description: Soft-mode structural phase transformations, common in many perovskite-based materials, are also found in La{sub 2}CuO{sub 4} and structurally related oxides. The resulting phase behavior is rather complex, but is a natural consequence of the degeneracy of the soft phonon order parameters. This paper reviews the structural and lattice-dynamical results and their interpretation based upon mean-field statistical mechanical models.
Date: December 31, 1991
Creator: Axe, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Scintillation Materials for Medical Applications. Annual Progress Report, January 1, 1991--December 31, 1992

Description: Scintillators are beginning to attract renewed attention because modern High Energy Physics accelerators are placing unprecedented demands of quantity and quality of detector materials and Positron Emission Tomography (PET), used by the medical field. Both applications required materials for scintillator detectors with properties beyond those delivered by traditional scintillators. Thallium doped halides are very efficient, but slow and chemically unstable. Two modern developments, namely the v… more
Date: December 31, 1992
Creator: Lempicki, A. & Wojtowicz, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Defect characterization of electronic conducting pseudo-perovskite systems. Final report

Description: The goal of the program has been to study the interrelationships between electrical conductivity, oxidation-reduction kinetics, defect structure, and composition of n- and p-type binary and ternary transition metal oxides. The stimulus for making these studies was the observation that both conducting n and p type oxides displayed a dependence on oxygen activity that was not predicted by the defect chemistry of their majority defects. The project has focused primarily on the understanding of ele… more
Date: December 31, 1994
Creator: Anderson, H. U.; Nasrallah, M.; Sparlin, D. M. & Parris, P. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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[Thermochemistry of phases related to oxide superconductors]. Progresss report

Description: The aim of this project has been to understand the crystal-chemical and energetic constraints on the stability of phases related to oxide superconductors, using high temperature reaction calorimetry, the unique expertise of this laboratory, coupled with synthesis and structural studies. The YBCO (Y{sub 2}O{sub 3}-BaO-Cu-O) system has been studied in detail by Zhou for his Ph.D. thesis, while DiCarlo has been studying alkaline earth doped lanthanium cuprates of the series La{sub 2-x}A{sub x}CuO{… more
Date: December 31, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stress analysis of hydride bed vessels used for tritium storage

Description: A prototype hydride storage bed, using LaNi{sub 4.25}Al{sub 0.75} as the storage material, was fitted with strain gages to measure strains occurring in the stainless steel bed vessel caused by expansion of the storage powder upon uptake of hydrogen. The strain remained low in the bed as hydrogen was added, up to a bed loading of about 0.5 hydrogen to metal atom ratio (H/M). The strain then increased with increasing hydrogen loading ({approximately} 0.8 H/M). Different locations exhibited greatl… more
Date: December 31, 1991
Creator: McKillip, S. T.; Bannister, C. E. & Clark, E. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Near-ambient X-ray photoemission spectroscopy and kinetic approach to the mechanism of carbon monoxide oxidation over lanthanum substituted cobaltites

Description: We have studied the oxidation of carbon monoxide over a lanthanum substituted perovskite (La0.5Sr0.5CoO3-d) catalyst prepared by spray pyrolysis. Under the assumption of a first-order kinetics mechanism for CO, it has been found that the activation energy barrier of the reaction changes from 80 to 40 kJ mol-1 at a threshold temperature of ca. 320 oC. In situ XPS near-ambient pressure ( 0.2 torr) shows that the gas phase oxygen concentration over the sample decreases sharply at ca. 300 oC. These… more
Date: July 31, 2009
Creator: Hueso, J. L.; Martinez-Martinez, D.; Cabalerro, Alfonso; Gonzalez-Elipe, Agustin Rodriguez; Mun, Bongjin Simon & Salmeron, Miquel
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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