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Final Project Report for ER15351 “A Study of New Actinide Zintl Ion Materials”

Description: The structural chemistry of actinide main-group metal materials provides the fundamental basis for the understanding of structural coordination chemistry and the formation of materials with desired or predicted structural features. The main-group metal building blocks, comprising sulfur-group, phosphorous-group, or silicon-group elements, have shown versatility in oxidation state, coordination, and bonding preferences. These building blocks have allowed us to elucidate a series of structures th… more
Date: November 12, 2007
Creator: Dorhout, Peter K.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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Electrocatalytic proton-reduction behaviour of telluride-capped triiron clusters: tuning of overpotentials and stabilization of redox states relative to lighter chalcogenide analogues

Description: Article investigating the utility of the non-biological element tellurium as a replacement for the widely biologically-utilized lighter chalcogenides sulfur and selenium in the realm of proton-reduction catalysis.
Date: May 14, 2020
Creator: Hrovat, David A.; Richmond, Michael G.; Rahaman, Ahibur; Lisensky, George C.; Browder-Long, Jess; Nordlander, Ebbe et al.
Item Type: Refine your search to only Article
Partner: UNT College of Science
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Formation of hollow nanocrystals through the nanoscale kirkendall effect

Description: We demonstrate that hollow nanocrystals can be synthesized through a mechanism analogous to the Kirkendall Effect, in which pores form due to the difference in diffusion rates between two components in a diffusion couple. Cobalt nanocrystals are chosen as a primary example to show that their reaction in solution with oxygen, sulfur or selenium leads to the formation of hollow nanocrystals of the resulting oxide and chalcogenides. This process provides a general route to the synthesis of hollow … more
Date: March 11, 2004
Creator: Yin, Yadong; Rioux, Robert M.; Erdonmez, Can K.; Hughes, Steven; Somorjai, Gabor A. & Alivisatos, A. Paul
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theory of Two-Magnon Raman Scattering in Iron Pnictides and Chalcogenides

Description: Although the parent iron-based pnictides and chalcogenides are itinerant antiferromagnets, the use of local moment picture to understand their magnetic properties is still widespread. We study magnetic Raman scattering from a local moment perspective for various quantum spin models proposed for this new class of superconductors. These models vary greatly in the level of magnetic frustration and show a vastly different two-magnon Raman response. Light scattering by two-magnon excitations thus pr… more
Date: August 15, 2011
Creator: Chen, C. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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FY 2005 Miniature Spherical Retroreflectors Final Report

Description: Research done by the Infrared Photonics team at Pacific Northwest National Laboratory (PNNL) is focused on developing miniature spherical retroreflectors using the unique optical and material properties of chalcogenide glass to reduce both performance limiting spherical and chromatic aberrations. The optimized optical performance will provide efficient signal retroreflection that enables a broad range of remote detection scenarios for mid-wave infrared (MWIR) and long-wave infrared (LWIR) sensi… more
Date: December 1, 2005
Creator: Anheier, Norman C.; Bernacki, Bruce E.; Johnson, Bradley R.; Riley, Brian J. & Sliger, William A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Single Dirac Cone Topological Surface State and Unusual Thermoelectric Property of Compounds from a New Topological Insulator Family

Description: Angle resolved photoemission spectroscopy (ARPES) study on TlBiTe2 and TlBiSe2 from a Thallium-based III-V-VI2 ternary chalcogenides family revealed a single surface Dirac cone at the center of the Brillouin zone for both compounds. For TlBiSe{sub 2}, the large bulk gap ({approx} 200meV) makes it a topological insulator with better mechanical properties than the previous binary 3D topological insualtor family. For TlBiTe{sub 2}, the observed negative bulk gap indicates it as a semi-metal, rathe… more
Date: August 18, 2011
Creator: Chen, Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Summary of Chalcogenide Glass Processing: Wet-Etching and Photolithography

Description: This report describes a study designed to explore the different properties of two different chalcogenide materials, As2S3 and As24S38Se38, when subjected to photolithographic wet-etching techniques. Chalcogenide glasses are made by combining chalcogen elements S, Se, and Te with Group IV and/or V elements. The etchant was selected from the literature and was composed of sodium hydroxide, isopropyl alcohol, and deionized water and the types of chalcogenide glass for study were As2S3 and As24S38S… more
Date: December 1, 2006
Creator: Riley, Brian J.; Sundaram, S. K.; Johnson, Bradley R. & Saraf, Laxmikant V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Origin of the pseudogap in high temperature superconductors

Description: Underdoped high temperature superconductors (HTS) exhibit a normal state for energies E > E{sub g} and/or temperatures T > T{sub 0}, and a pseudogap in their electronic spectrum for E < E{sub g} and/or T{sub 0} > T > {Tc}. Strikingly similar behavior occurs in the transition metal dichalcogenides (TMD) 2H-MX{sub 2}, where M = Ta, Nb, and X = S, Se, both in the normal (T > T{sub 0}) and in the incommensurate charge-density wave (T{sub ICDW} > T > T{sub c}) states. Such st… more
Date: February 8, 2000
Creator: Klemm, R. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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FY 2005 Infrared Photonics Final Report

Description: Research done by the Infrared Photonics team at Pacific Northwest National Laboratory (PNNL) is focused on developing miniaturized integrated optics for mid-wave infrared (MWIR) and long-wave infrared (LWIR) sensing applications by exploiting the unique optical and material properties of chalcogenide glass. PNNL has developed thin-film deposition capabilities, direct laser writing techniques, infrared photonic device demonstration, holographic optical element design and fabrication, photonic de… more
Date: December 1, 2005
Creator: Anheier, Norman C.; Allen, Paul J.; Ho, Nicolas; Krishnaswami, Kannan; Johnson, Bradley R.; Sundaram, S. K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New class of diode-pumped, mid-IR, broadly-tunable lasers based on TM{sup 2+} lons in T{sub d} coordination: Cr{sup 2+}:ZnX (X=S,Se)

Description: A new class of room-temperature, diode-pumped solid state lasers, that are broadly tunable in the mid-infrared spectral region, has been conceptualized and demonstrated. These lasers are based on intra-ion transitions of divalent transition metals placed in substitutional cation sites of tetrahedral symmetry in large bandgap chalcogenide semiconductor crystals. These combinations of laser-ions and host crystals are seen to provide favorable radiative and non-radiative transition processes for t… more
Date: January 1, 1997
Creator: Krupke, W. F.; Page, R. H.; Schaffers, K. I.; Payne, S. A.; Beach, R. J.; Skidmore, J. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fracture analysis of optical fibers

Description: The fracture markings on glass optical fiber surfaces are quantitatively related to the strength and time under load. Knowledge of the fracture-initiating defects and the surrounding topography pinpoints the source of failure, aids in troubleshooting, and improves production procedures. It is shown that the techniques of fracture surface analysis help analyze in-service failures as well as improve fiber optic production control.
Date: January 1, 1980
Creator: Mecholsky, J.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of plutonium oxide leak rates from shipping containers. Quarterly progress report, October 1, 1977--December 31, 1977

Description: The study was initiated in Oct. 1976. Several tasks are to be undertaken. In combination, they have the end objective of defining the leak rates of plutonium oxide from characterized leaks in shipping containers. Research progress is reported on each of the four tasks. (TFD)
Date: January 1, 1978
Creator: Schwendiman, L. C.; Pobereskin, M.; Mishima, J.; Sutter, S. L.; Madia, W. J.; Schmidt, E. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Driving Oxygen Coordinated Ligand Exchange at Nanocrystal Surfaces using Trialkylsilylated Chalcogenides

Description: A general, efficient method is demonstrated for exchanging native oxyanionic ligands on inorganic nanocrystals with functional trimethylsilylated (TMS) chalcogenido ligands. In addition, newly synthesized TMS mixed chalcogenides leverage preferential reactivity of TMS-S bonds over TMS-O bonds, enabling efficient transfer of luminescent nanocrystals into aqueous media with retention of their optical properties.
Date: November 11, 2010
Creator: Caldwell, Marissa A.; Albers, Aaron E.; Levy, Seth C.; Pick, Teresa E.; Cohen, Bruce E.; Helms, Brett A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hand punching holes in unfired 99. 5 percent alumina substrates

Description: The tooling and process techniques for hand-punching holes in green (unfired) 99.5 percent alumina ceramic substrates were investigated to determine the requirements for obtaining holes with good surface finish and a minimum number of defects. Such holes are needed to provide low electrical resistance ground paths from frontside to backside of vacuum-metallized ceramic substrates used to manufacture hybrid microcircuits. It was determined that holes having excellent surface finish and maximum v… more
Date: August 1, 1976
Creator: Blessner, P. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some thermoelectric properties of the light rare earth sesquiselenides (R/sub 2/Se/sub 3-x/)

Description: Rare earth sesquiselenides of the Th/sub 3/P/sub 4/ structure show variable electric properties over their homogeneity range, i.e., ranging from metallic (R/sub 3/Se/sub 4/) to semimetallic (R/sub 2/Se/sub 3-x/, where 0.14 > x > 0) to semiconducting (R/sub 2/Se/sub 3/). The composition change is due to the formation of metal vacancies in the Th/sub 3/P/sub 4/ structure with no vacancies at R/sub 3/Se/sub 4/ and 4.75 at. % vacancies at R/sub 2/Se/sub 3/. The rare earth sesquiselenides are also r… more
Date: January 1, 1981
Creator: Takeshita, T.; Beaudry, B. J. & Gschneidner, K. A., Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synthesis, characterization, and structure of reduced tungsten chalcogenide cluster complexes

Description: Over the previous twenty years, ternary molybdenum chalcogenides of the general formula M{sub x}Mo{sub 6}Y{sub 8} (M = ternary metal cation; Y = chalcogenide), known as Chevrel phases, have been extensively studied. Many of these compounds have been found to have superconductivity, catalytic activity and ionic conductivity. The rich chemistry of the Chevrel phases raises considerable interest in finding the tungsten analogues of these phases. However, no such analogue has ever been synthesized,… more
Date: February 1, 1997
Creator: Xiaobing, Xie
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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State of the art: alumina ceramics for energy applications

Description: Prominent ceramic raw materials and products manufacturers were surveyed to determine the state of the art for alumina ceramic fabrication. This survey emphasized current capabilities and limitations for fabrication of large, high-density, high-purity, complex shapes. Some directions are suggested for future needs and development.
Date: January 1, 1978
Creator: Hauth, W. E. & Stoddard, S. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of plutonium oxide leak rates from shipping containers. Quarterly progress report, April 1, 1977--June 30, 1977

Description: The study was initiated in October, 1976. Several tasks are to be undertaken in the study. In combination, they have the end objective of defining the leak rates of plutonium oxide powder from characterized leaks. This is the third quarterly report of this work. Previous reports were issued as BNWL-2260-1 and -2. Progress on each of the tasks is reported. (TFD)
Date: July 1, 1977
Creator: Schwendiman, L. S.; Pobereskin, M.; Mishima, J.; Sutter, S. L.; Madia, W. J.; Schmidt, E. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Emerging nuclear energy systems: Economic challenge: Revision 1

Description: Future nuclear energy systems may achieve substantially lower energy costs than those of existing fossil energy systems and comparable capital costs. Such low cost nuclear energy would provide a strong economic incentive to minimize the use of fossil fuels. If these low cost nuclear energy systems emerge in the next few decades, 21st century civilization may be able to avert potentially disastrous CO/sub 2/ induced global climate changes. 12 refs., 1 fig.
Date: January 1, 1986
Creator: Nuckolls, J.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microwave sintering of large alumina bodies

Description: The application of microwaves as an energy source for materials processing of large alumina bodies at elevated temperatures has been limited to date. Most work has concerned itself with small laboratory samples. The nonuniformity of the microwave field within a cavity subjects large alumina bodies to areas of concentrated energy, resulting in uneven heating and subsequent cracking. Smaller bodies are not significantly affected by field nonuniformity due to their smaller mass. This work will dem… more
Date: January 1, 1993
Creator: Blake, R. D. & Katz, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Key statistics related to CO/sub 2/ emissions: Significant contributing countries

Description: This country selection task report describes and applies a methodology for identifying a set of countries responsible for significant present and anticipated future emissions of CO/sub 2/ and other radiatively important gases (RIGs). The identification of countries responsible for CO/sub 2/ and other RIGs emissions will help determine to what extent a select number of countries might be capable of influencing future emissions. Once identified, those countries could potentially exercise cooperat… more
Date: July 1, 1987
Creator: Kellogg, M. A.; Edmonds, J. A.; Scott, M. J. & Pomykala, J. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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