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Measurement of viscosity, density, and gas solubility of refrigerant blends in selected synthetic lubricants. Final report

Description: The lubricants tested in this project were chosen based on the results of liquid/liquid miscibility tests. EMKARATE RL32S and Emery 2968A were selected. The Vapor Liquid Equilibrium (VLE) viscosity reduction and gas fractionation of each was measured with three different refrigerant blends: (1) R-404A; (2) R-507; and (3) R-407C. In addition, the four single refrigerants that make up the blends, HFC-32, HFC-125, HFC-134a, and HFC-143a, were also measured. Lubricants found to have the lowest liqu… more
Date: May 15, 1995
Creator: Cavestri, R.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fullerene-based materials research and development. LDRD final report

Description: The chemistry and physical properties of fullerenes, the third, molecular allotrope of carbon, have been studied using both experimental and computational techniques. Early computational work investigated the stability of fullerene isomers and oxides, which was followed by extensive work on hydrogenated fullerenes. Our work led to the first synthesis of a polymer containing C{sub 60} and the synthesis of the simplest hydrocarbon derivatives of C{sub 60} and C{sub 70}. The excellent agreement be… more
Date: May 1, 1995
Creator: Cahill, P. A.; Henderson, C. C.; Rohlfing, C. M.; Loy, D. A.; Assink, R. A.; Gillen, K. T. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A diethyl phosphonate containing oxazoline: Synthesis and characterization of monomer and homopolymer

Description: A diethyl phosphonate oxazoline monomer and its polymer have been synthesized. The monomer appears to polymerize via a ring-opening mechanism giving the expected polyethyleneimine backbone with pendant carbonyl groups. Two distinct molecular weights were produced during polymerization suggesting two mechanisms of chain growth. Studies are underway to elucidate the reasons for this. This polymer has potential as a metal-chelating agent.
Date: May 1, 1995
Creator: Hermes, R.E.; Thompson, R.D. & Valdez, L.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of the reaction rates between uranium and liquid aluminum

Description: A limited study consisting of scoping experiments was carried out to determine if a uranium-niobium alloy was weakly or strongly resistant to penetration by liquid aluminum alloy 6061. Our investigation was limited to temperatures between 700{degrees}and 900{degrees}C and carried out using small cylindrical coupons of U-6wt.%Nb and unalloyed U in unsaturated molten aluminum and aluminum alloy 6061 baths. The results indicate that indeed, significant dissolution of uranium into molten aluminum o… more
Date: May 5, 1995
Creator: Strum, M. J.; Sedillo, E. & Smugeresky, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sorption and chemical transformation of PAH`s on coal fly ash

Description: The major objective of this work was to characterize the interactions of coal fly ash with polycyclic aromatic hydrocarbons (PAHS) and their derivatives, and to attempt to understand the influence of the surface properties of coal ash (and other atmospheric particles) on the chemical transformations of polycyclic aromatic compounds. Our studies have concentrated on the photochemical behavior of PAHs sorbed form the vapor phase on coal fly ashes, and compositional subfractions obtained therefrom… more
Date: May 9, 1995
Creator: Mamantov, G. & Wehry, E. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Direct Catalytic Conversion of Methane and Light Hydrocarbon Gases Quarterly Report: Number 6

Description: The goal of this research is to develop catalysts that directly convert methane and light hydrocarbons to intermediates that later can be converted to either liquid fuels or value-added chemicals, as economics dictate. During this reporting period, we synthesized several phthalocyanine catalysts supported on magnesia (MgO) in Task 3. In Task 4 we have tested these catalysts for oxidation of methane and did a number of blank experiments to determine the cause of the low methanol yield we have ob… more
Date: May 20, 1988
Creator: Wilson, Robert B., Jr.; Chan, Yee Wai & Posin, B. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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60-day safety screen results and final report for tank 241-C-111, auger samples 95-Aug-002, 95-Aug-003, 95-Aug-016, and 95-Aug-017

Description: This report presents the details of the auger sampling events for underground waste tank C-111. The samples were shipped to the 222-S laboratories were they underwent safety screening analysis and primary ferricyanide analysis. The samples were analyzed for alpha total, total organic carbon, cyanide, Ni, moisture, and temperature differentials. The results of this analysis are presented in this document.
Date: May 30, 1995
Creator: Rice, A.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis on the sequence of formation of Ti{sub 3}SiC{sub 2} and Ti{sub 3}SiC{sub 2}/SiC composites

Description: Ti{sub 3}SiC{sub 2}, a compound in the ternary Ti-Si-C system, is reported to be ductile. This paper reports the sequence of formation of Ti{sub 3}SiC{sub 2} and Ti{sub 3}SiC{sub 2}/SiC composites involving either combustion synthesis or by displacement reaction, respectively. Onset of exothermic reaction temperatures were determined using Differential Thermal Analysis (DTA). Phases present after the exothermic temperatures were analyzed by X-Ray diffraction. Based on these observations, a rout… more
Date: May 1, 1995
Creator: Radhakrishnan, R.; Bhaduri, S.B. & Henager, C.H. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Alkaline chemistry of transuranium elements and technetium and the treatment of alkaline radioactive wastes

Description: Goal of this survey is to generalize the known data on fundamental physical-chemical properties of TRUs and Tc, methods for their isolation, and to provide recommendations that will be useful for partitioning them from alkaline high-level wastes.
Date: May 1, 1995
Creator: Delegard, C. H.; Peretrukhin, V. F.; Shilov, V. P. & Pikaev, A. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Sandia National Laboratories (SNL) and Oak Ridge National Laboratories (ORNL) joint development of SNL`s sample tracking, analysis and reporting (STAR) information system

Description: A comprehensive environmental sample management program allocates much of its resources to collecting, managing, and manipulating information. A computerized system that collects information at the field sampling point, tracks the sample to analytical labs and loads electronic data deliverables from these labs, while maintaining chain of custody and data integrity, is efficient and cost effective for providing consistent and accurate, legally defensible sample data. In June 1993, a team was for… more
Date: May 1, 1995
Creator: Fish, J.; Campbell, D. & Jenkins, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recovery of Propylene Glycol From Dilute Aqueous Solutions by Reversible Chemical Complexation With Organoboronates

Description: Extractants consisting of an ion-pair of Aliquat 336 with phenylboronate or 3-nitrophenylboronate were prepared in various diluents (2-ethylhexanol, toluene, o-xylene or diisobutylketone). In batch experiments propyleneglycol (1,2-PD) was effectively extracted even at low concentrations. Heterogeneous complexation constants {beta}{sub 11} calculated at 25 C were 45-120 (mol/1){sup {minus}1} in 2-ethylhexanol, 34.8 (mol/l){sup {minus}1} in toluene, 37.6 (mol/l){sup {minus}1} in o-xylene and 14.4… more
Date: May 1, 1995
Creator: Broekhuis, R. R.; Lynn, S. & King, C. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ultrafast studies of photodissociation in solution: Dissociation, recombination and relaxation

Description: Photodissociation of M(CO){sub 6} (M=Cr,Mo,W) and the formation of solvated M(CO){sub 5}{center_dot}S complex was studied in cyclohexane; rate-limiting step is vibrational energy relaxation from the new bond to the solvent. For both M=Cr and Mo, the primary relaxation occurs in 18 ps; for Cr, there is an additional vibrational relaxation (150 ps time scale) of a CO group poorly coupled to other modes. Relaxation of M=W occurs in 42 ps; several possible mechanisms for the longer cooling are disc… more
Date: May 1, 1995
Creator: King, J. C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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NO decomposition in non-reducing atmospheres. Technical progress report, December 1994--February 1995

Description: The overall goal of this research is to establish the fundamental science needed to develop catalysts that will exhibit high activity and selectivity in the decomposition of NO into N{sub 2} and O{sub 2}. This project is centered on the preparation, characterization, and testing of transition metal exchanged catalysts, especially Co(III) zeolites. Additional Co(II) exchanged A zeolite samples have been prepared in aqueous solution at pH = 5.0-6.1 that contain different exchange levels of Co(II)… more
Date: May 1, 1995
Creator: Klier, Kamil; Herman, Richard G. & Jirka, Ivan
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Trivalent metallocene chemistry of some uranium, titanium, and zirconium complexes

Description: Dicyclopentadienyluranium halide dimers have been prepared and their solution behavior examined. These molecules exist as dimers in solution, and the halide ligands undergo rapid site exchange on the NMR timescale above 50 C. Analogous dicyclopentadienyluranium hydroxide dimers have also been prepared; they oxidatively eliminate hydrogen to give the corresponding oxide dimers. Mechanism of this reaction is consistent with {alpha}migration of one of the hydroxide hydrogen atoms to a uranium cent… more
Date: May 1, 1995
Creator: Lukens, W. W., Jr.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Solubility-limited concentrations and aqueous speciation fo U, Pu, Np, Am and Tc: Comparison between results of Bruno and Sellin (1992) and calculations using GEMBOCHS (version R16)

Description: Aqueous speciation and solubility-limited concentrations of U, Pu, Np, Am and Tc were calculated with EQ3/6 and version comR16 of the GEMBOCHS data base for comparison to similar calculations made by Bruno and Sellin (1992) for the SKB 91 exercise. Bruno and Sellin utilized data from the older 0288 version of the EQ3/6 data base but substituted their own data sets for U and Pu. Equilibria were computed in representative fresh and saline Finnsjoen-waters under oxidizing and reducing conditions. … more
Date: May 1, 1995
Creator: Bruton, C. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Environmental Geochemistry for Surface and Subsurface Waters in the Pajarito Plateau and Outlying Areas, New Mexico

Description: This report provides background information on waters in the Los Alamos and Santa Fe regions of northern New Mexico. Specifically, the presented data include major element, trace element, and isotope analyses of 130 water samples from 94 different springs, wells, and water bodies in the area. The region considered in this study extends from the western edge of the Valles Caldera to as far east as Santa Fe Lake. For each sample, the presented analysis includes fourteen different major elements, … more
Date: May 1, 1995
Creator: Blake, W. D.; Goff, F.; Adams, A. I. & Counce, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis, structure, and reactivity of high oxidation state silver fluorides and related compounds

Description: This thesis has been largely concerned with defining the oxidizing power of Ag(III) and Ag(II) in anhydrous hydrogen fluoride (aHF) solution. Emphasis was on cationic species, since in a cation the electronegativity of a given oxidation state is greatest. Cationic Ag(III) solv has a short half life at ordinary temperatures, oxidizing the solvent to elemental fluorine with formation of Ag(II). Salts of such a cation have not yet been preparable, but solutions which must contain such a species ha… more
Date: May 1, 1995
Creator: Lucier, G.M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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{sup 40}Ar/{sup 39}Ar laser fusion and K-Ar ages from Lathrop Wells, Nevada, and Cima, California: The age of the latest volcanic activity in the Yucca Mountain area

Description: K-Ar and {sup 40}Ar/{sup 39}Ar ages from the Lathrop Wells volcanic center, Nevada, and from the Cima volcanic field, California, indicate that the recently reported 20-ka age estimate for the Lathrop Wells volcanic center is incorrect. Instead, an age of 119 {plus_minus} 11 to 141 {plus_minus} 10 ka is indicated for the Lathrop Wells volcanic center. This age corrected is concordant with the ages determined by two independent isotopic geochronometric techniques and with the stratigraphy of sur… more
Date: May 1, 1991
Creator: Turrin, B. D. & Champion, D. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Density of metallic polonium

Description: Determinations of the density and coefficient of thermal expansions of postum (Polonium 210) were attempted on 20 curies of polonium as obtained from production foils.
Date: May 18, 1948
Creator: Brody, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Crossed molecular beams study of O({sup 1}D) reactions with H{sub 2} molecules

Description: Reaction dynamics of O({sup 1}D) atoms with H{sub 2} molecules was reinvestigated using the crossed molecular beams technique with pulsed beams. The O({sup 1}D) beam was generated by photodissociating O{sub 3} molecules at 248 nm. Time-of-flight spectra and the laboratory angular distribution of the OH products were measured. The derived OH product center-of-mass flux-velocity contour diagram shows more backward scattered intensity with respect to the O({sup 1}D) beam. In contrast to previous s… more
Date: May 1, 1995
Creator: Miau, T.T.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Elemental analysis of waste glass by x-ray fluorescence spectrometry

Description: An X-ray fluorescence (XRF) technique is reported which shows promise for the elemental analysis of low-level mixed waste glasses. This technique can be used for both quantitative laboratory analysis and process control. The glass-forming melts are cast into graphite molds and resulting disks are annealed and polished. The disk is then analyzed with a wavelength dispersive X-ray fluorescence spectrometer and the elemental intensities are converted into concentration with a fundamental parameter… more
Date: May 1, 1995
Creator: Bickford, Dennis F.; Jurgensen, Arthur R.; Resce, James L.; Ragsdale, R. Giles & Overcamp, Tom J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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45-day safety screen results for tank 241-U-204, push mode, cores 81 and 82

Description: This is the 45-Day report for the fiscal year 1995 tank 241-U-204 (U-204) push-mode characterization effort. Included are a summary of analytical results and copies of the differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) scans. Core samples 81 and 82 from tank U-204, obtained by the push-mode core sampling method, were received by the 222-S Laboratories. Each core consisted of only one segment. Both core samples and the field blank were extruded, subsampled, and anal… more
Date: May 17, 1995
Creator: Bell, Kevin E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Selective, pulsed CVD of platinum on microfilament gas sensors

Description: A post-processing, selective micro-chemical vapor deposition (``micro-CVD``) technology for the deposition of catalytic films on surface-micromachined, nitride-passivated polysilicon filaments has been investigated. Atmospheric pressure deposition of Pt on microfilaments was accomplished by thermal decomposition of Pt acetylacetonate; deposition occurs selectively only on those filaments which are electrically heated. Catalyst morphology, characterized by SEM, can be controlled by altering depo… more
Date: May 1, 1996
Creator: Manginell, Ronald P.; Smith, James H.; Ricco, Antonio J.; Moreno, Daniel J.; Hughes, Robert C.; Huber, Robert J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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