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Chemical Research Section Progress Report for January 1950

Description: The following documents are progress reports that follow chemical research studies in subjects such as ruthenium tetroxile distillations, extraction-scrub studies of zirconium and niobium, and oxidation of plutonium and stabilization of plutonium(VI) during extraction of IAF solutions.
Date: February 15, 1950
Creator: Albaugh, F. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transformations in uranium-base alloys : summary report, December 14, 1955 - March 31, 1957

Description: From abstract: "Transformation kinetics of binary U -Nb and ternary U-Nb-base alloys were investigated. Additions included zirconium, chromium, titanium, silicon, nickel, nnthenium, and vanadium. Encapsulated samples were given a homogenizstion anneal at 1000 or 1100/sup o/C, water-quenched from 906/sup o/C to retain the phase, and reheated to temperatures between 360 and 600/sup o/C. The metastability of the phase was examined by metallographic, hardness, resistometric, dilatometric and x-ray-… more
Date: 1957
Creator: Parry, Sidney J. S.; Holtz, F. C. & Van Thyne, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Substitution Chemistry of Ruthenium Clusters with the Diphosphine Ligands: 4,5-Bis(Diphenylphosphino)-4-Cyclo-Penten-1,3-Dione (bpcd), (Z)-Ph₂PCH=CHPP₂ and 3,4-Bis(Diphenylphosphino)-5-Methoxy-2(5H)-Furanone (bmf)

Description: The chemistry of transition metal clusters has been a fast developing area of organometallic research in recent years. Compared to mononuclear metal complexes, polynuclear clusters offer more opportunities to study cooperative effects and electron reservoir properties between contiguous metal centers, in addition to functioning as storehouses for the release of catalytically active small fragments capable of exhibiting heterosite subtrate activation. Theoretically, metal clusters are intermedia… more
Date: May 1997
Creator: Shen, Huafeng
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Computational Studies of Selected Ruthenium Catalysis Reactions.

Description: Computational techniques were employed to investigate pathways that would improve the properties and characteristics of transition metal (i.e., ruthenium) catalysts, and to explore their mechanisms. The studied catalytic pathways are particularly relevant to catalytic hydroarylation of olefins. These processes involved the +2 to +3 oxidation of ruthenium and its effect on ruthenium-carbon bond strengths, carbon-hydrogen bond activation by 1,2-addition/reductive elimination pathways appropriate … more
Date: December 2007
Creator: Barakat, Khaldoon A.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Tantalum- and ruthenium-based diffusion barriers/adhesion promoters for copper/silicon dioxide and copper/low κ integration.

Description: The TaSiO6 films, ~8Å thick, were formed by sputter deposition of Ta onto ultrathin SiO2 substrates at 300 K, followed by annealing to 600 K in 2 torr O2. X-ray photoelectron spectroscopy (XPS) measurements of the films yielded a Si(2p) binding energy at 102.1 eV and Ta(4f7/2) binding energy at 26.2 eV, indicative of Ta silicate formation. O(1s) spectra indicate that the film is substantially hydroxylated. Annealing the film to > 900 K in UHV resulted in silicate decomposition to SiO2 and Ta2… more
Date: December 2004
Creator: Zhao, Xiaopeng
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Synthesis and characterization of diphosphine ligand substituted osmium and ruthenium clusters.

Description: The kinetics for the bridge-to-chelate isomerization of the dppe ligand in H4Ru4(CO)10(dppe) have been investigated by UV-vis and NMR spectroscopies over the temperature range of 308-328 K. The isomerization of the ligand-bridged cluster 1,2-H4Ru4(CO)10(dppe) was found to be reversible by 31P NMR spectroscopy, affording a Keq = 15.7 at 323 K in favor of the chelating dppe isomer. The forward (k1) and reverse (k-1) first-order rate constants for the reaction have been measured in different sol… more
Date: August 2007
Creator: Kandala, Srikanth
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Materials properties of ruthenium and ruthenium oxides thin films for advanced electronic applications.

Description: Ruthenium and ruthenium dioxide thin films have shown great promise in various applications, such as thick film resistors, buffer layers for yttrium barium copper oxide (YBCO) superconducting thin films, and as electrodes in ferroelectric memories. Other potential applications in Si based complementary metal oxide semiconductor (CMOS) devices are currently being studied. The search for alternative metal-based gate electrodes as a replacement of poly-Si gates has intensified during the last few … more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2006
Creator: Lim, ChangDuk
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Interfacial Electrochemistry of Metal Nanoparticles Formation on Diamond and Copper Electroplating on Ruthenium Surface

Description: An extremely facile and novel method called spontaneous deposition, to deposit noble metal nanoparticles on a most stable form of carbon (C) i.e. diamond is presented. Nanometer sized particles of such metals as platinum (Pt), palladium (Pd), gold (Au), copper (Cu) and silver (Ag) could be deposited on boron-doped (B-doped) polycrystalline diamond films grown on silicon (Si) substrates, by simply immersing the diamond/Si sample in hydrofluoric acid (HF) solution containing ions of the correspon… more
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Date: May 2003
Creator: Arunagiri, Tiruchirapalli Natarajan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Cu Electrodeposition on Ru with a Chemisorbed Iodine Surface Layer.

Description: An iodine surface layer has been prepared on Ru(poly) and Ru(0001) electrodes by exposure to iodine vapor in UHV and polarizing in a 0.1 M HClO4/0.005 M KI solution, respectively. A saturation coverage of I on a Ru(poly) electrode passivates the Ru surface against significant hydroxide, chemisorbed oxygen or oxide formation during exposure to water vapor over an electrochemical cell in a UHV-electrochemistry transfer system. Immersion of I-Ru(poly) results in greater hydroxide and chemisorbed o… more
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Date: August 2005
Creator: Lei, Jipu
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Diphosphine Ligand Substitution in H4Ru4(CO)12: X-ray Diffraction Structures and Reactivity Studies of the Diphosphine Substituted Cluster Products

Description: The tetraruthenium cluster H4Ru4(CO)12 has been studied for its reactivity with the unsaturated diphosphine ligands (Z)-Ph2PCH=CHPPh2, 4,5-bis (diphenylphosphino)-4-cyclopenten-1,3-dione, bis(diphenyphosphino)benzene and 1,8- bis(diphenyl phosphino)naphthalene under thermal, near-UV photolysis, and Me3NO-assisted activation. All three cluster activation methods promote loss of CO and furnish the anticipated substitution products that possess a chelating diphosphine ligand. Clusters 1, 2, 3 and … more
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Date: December 2006
Creator: Kandala, Srikanth
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Denitration Loss of Ruthenium from Uranyl Nitrate Beta Mounts

Description: Abstract: "During the preparation of beta-gamma mounts of uranyl nitrate it is possible to affect a denitration loss of approximately 80% of the ruthenium. By adding hydroxylamine sulfate and sulfuric acid, the ruthenium is stabilized and the denitration loss is eliminated. The standard determination of ruthenium by calculation, utilizing a differential counting technique has been found to be approximately the same as the standard denitration of radiochemical assays."
Date: 1955
Creator: Mahlman, H. A. & Decker, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of Silver Deposition on Silicon (100) by IR Spectroscopy and Patina Formation Study of Oxygen Reduction Reaction on Ruthenium or Platinum

Description: To investigate conditions of silver electroless deposition on silicon (100), optical microscope, atomic force microscope (AFM) and attenuated total reflection infrared spectroscopy (ATR-FTIR) spectroscopy were used. Twenty second dipping in 0.8mM AgNO3/4.9% solution coats a silicon (100) wafer with a thin film of silver nanoparticles very well. According to AFM results, the diameter of silver particles is from 50 to 100nm. After deposition, arithmetic average of absolute values roughness (Ra) i… more
Date: August 2009
Creator: Yang, Fan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Scavenging of Ruthenium From Purex Uranyl Nitrate Solution

Description: From introduction: "In previous work on the ion exchange adsorption of ruthenium, it was observed that when certain compounds of sulfur were added to dilute uranyl nitrate solutions, precipitates formed which carried ruthenium. The purpose of this investigation was to develop a similar method for scavenging ruthenium from concentrated uranyl nitrate solutions. Such a method, combined with the silica gel treatment for removing zirconium and niobium, might provide an integrated process to remove … more
Date: June 1958
Creator: Prohaska, Charles A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Copper Electrodeposition on Iridium, Ruthenium and Its Conductive Oxide Substrate

Description: The aim of this thesis was to investigate the physical and electrochemical properties of sub monolayer and monolayer of copper deposition on the polycrystalline iridium, ruthenium and its conductive oxide. The electrochemical methods cyclic voltammetry (CV) and chronocoulometry were used to study the under potential deposition. The electrochemical methods to oxidize the ruthenium metal are presented, and the electrochemical properties of the oxide ruthenium are studied. The full range of … more
Date: December 2003
Creator: Huang, Long
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Study of Ruthenium and Ruthenium Oxide's Electrochemical Properties and Application as a Copper Diffusion Barrier

Description: As a very promising material of copper diffusion barrier for next generation microelectronics, Ru has already obtained a considerable attention recently. In this dissertation, we investigated ruthenium and ruthenium oxide electrochemical properties and the application as a copper diffusion barrier. Cu under potential deposition (UPD) on the RuOx formed electrochemically was first observed. Strong binding interaction, manifesting by the observed Cu UPD process, exists between Cu and Ru as well … more
Date: August 2005
Creator: Zhang, Yibin
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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