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Development of glass formulations containing high-level nuclear wastes

Description: The effects of Na/sub 2/O, K/sub 2/O, B/sub 2/O/sub 3/, TiO/sub 2/, CaO, and ZnO contents were determined on the leach rate and homogeneity of a potential high-level waste glass. It was found that the two characteristics are in competition, with variations of CaO having the greatest effect and TiO/sub 2/ having the least effect. Boron oxide content is important in control of Na/sub 2/MoO/sub 4/ formation and separation. Sodium molybdate formation can also be controlled by the use of reducing ag… more
Date: February 1, 1978
Creator: Ross, W.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phase Transformations in Alumina. Technical Report, May to December 1961

Description: e transformation studies showed that synthetic aluminas produced in the laboratory were not transformed to alpha alumina at 400 to 700' deg n the presence of nitric acid and water vapor. Amorphous aluminn produced in the pilot plant was transformed to alpha alumina. This indicated that the amorphous alumina produced in the pilot plant is structurally predisposed to form alpha alumina. Most additives did not appear to have any special effects. Lithium formed zeta alumina, LiAl/sub 5/O/sub 8/. Ph… more
Date: December 1, 1961
Creator: Eding, H J; Huggins, M L & Brown, A G
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Trace Metal Speciation in Saline Waters Affected by Geothermal Brines. [GEOCHEM]

Description: A description is given of the chemical equilibrium computer program GEOCHEM, which has been developed to calculate trace element speciation in soil, irrigation, drainage, or Salton Sea waters affected by geothermal brine. GEOCHEM is applied to irrigation water-brine mixtures and to Salton Sea water-brine mixtures in order to compute the chemical speciation of the elements Cd, Cu, Hg, Ni, Pb, and Zn, along with the oxyanions of As and B. The results suggest that the computer simulation can have … more
Date: November 1, 1977
Creator: Sposito, G. & Page, A. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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THE CONTINUOUS MONITORING OF BORIC ACID CONCENTRATION BY NEUTRON ABSORPTIOMETRY

Description: A neutron absorption cell was built to monttor continuously the boric actd concentration of reactor water flowing through a purtfication loop. The instrument was calibrated over the range from 0 to 2.65 g/l with a maxtmum absolute error of 0.05 g/-l. (auth)
Date: October 1, 1961
Creator: Armani, R.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Inelastic scattering from amorphous solids

Description: The potential of inelastic neutron scattering techniques for surveying various aspects of the dynamics of amorphous solids is briefly reviewed. The recent use of the Intense Pulsed Neutron Source to provide detailed information on the optical vibrations of glasses is discussed in more detail. The density of states represents an averaged quantity which gives information about the general characteristics of the structure and bonding. More extensive information can be obtained by studying the deta… more
Date: August 1, 1985
Creator: Price, D.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low-frequency nuclear quadrupole resonance with a dc SQUID

Description: Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and applicati… more
Date: July 1, 1991
Creator: Chang, J.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optimization of glass composition for the vitrification of nuclear waste at the Savannah River Plant

Description: Waste glasses of different compositions were compared in terms of leachability, viscosity, liquidus temperature, and coefficient of expansion. The compositions of the glasses were determined by statistical optimization. Waste glass of the optimized composition is more durable than the current reference composition but can still be processed at low temperature.
Date: January 1, 1982
Creator: Soper, P. D.; Roberts, G. J.; Lightner, L. F.; Walker, D. D. & Plodinec, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of composition on properties in an 11-component nuclear waste glass system

Description: Ninety simplified nuclear waste glass compositions within an 11-component oxide composition matrix were tested for crystallinity, viscosity, volatility, and chemical durability. Empirical models of property response as a function of glass composition were developed using statistical experimental design and modeling techniques. A new statistical technique was developed to calculate the effects of oxide components on each property. Independent melts were used to check the prediction accuracy of t… more
Date: September 1, 1981
Creator: Chick, L. A.; Piepel, G. F.; Mellinger, G. B.; May, R. P.; Gray, W. J. & Buckwalter, C. Q.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of glass compositions for immobilization of Savannah River Plant waste

Description: Two fundamental problems related to processing Savannah River Plant wastes are the formation of ferrite-spinel crystals during melting, and the high viscosity and ready devitrification of high aluminum sludge-melts. The effects of several glass composition variables on these processing problems have been investigated. The most important variables are the TiO/sub 2/ content, the molar alkali-to-silica ratio, and the molar ratio of Li/sub 2/O to total alkali. As the TiO/sub 2/ content decreases, … more
Date: January 1, 1978
Creator: Plodinec, M.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

First-order model for durability of Hanford waste glasses as a function of composition

Description: Two standard chemical durability tests, the static leach test MCC-1 and product consistency test PCT, were conducted on simulated borosilicate glasses that encompass the expected range of compositions to be produced in the Hanford Waste Vitrification Plant (HWVP). A first-order empirical model was fitted to the data from each test method. The results indicate that glass durability is increased by addition of Al{sub 2}O{sub 3}, moderately increased by addition of ZrO{sub 2} and SiO{sub 2}, and d… more
Date: April 1, 1992
Creator: Hrma, P.; Piepel, G. F.; Schweiger, M. J. & Smith, D. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SiO sub 2 Membranes for H sub 2 Separation in Coal Gas Processing

Description: The project objectives are (1) to synthesize permselective ceramic membranes by chemical vapor deposition of SiO{sub 2} and other oxides within the walls of porous support tubes, (2) measure membrane permeability and thermal stability to various gases at 200--700{degrees}C and (3) develop a mathematical model for the chemical vapor deposition of the permselective oxide within the porous support tube.
Date: January 1, 1990
Creator: Gavalas, G. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of glass compositions for immobilization of SRP waste

Description: An improved composition of glass frit, termed 411, was developed for the immobilization of SRP high-level radioactive waste. In comparison with frit compositions previously studied, the new composition offers the following advantages: the amount of ferrite-spinel crystals formed is greatly decreased because the TiO/sub 2/ content is much lower; a higher lithium-to-sodium ratio decreases the viscosity of glass mixtures containing high-aluminum waste. The compositional studies leading to the deve… more
Date: February 1, 1979
Creator: Plodinec, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Relationship between borosilicate glass composition, structure, and durability test response (SRS)

Description: The chemical durability of 30 glasses from the Na[sub 2]O [center dot] B[sub 2]O[sub 3] [center dot] SiO[sub 2] [center dot] Al[sub 2]O[sub 3] [center dot] Fe[sub 2]O[sub 3][center dot]CaO system was examined. Two standard leach tests, MCC-1P and PCT, were performed in unbuffered, deionized water. PCT tests were performed for durations up to twenty-four weeks to obtain glass dissolution rate data. Short-term MCC-1P test leachate solutions are determined by the glass composition. Long-term glass… more
Date: January 1, 1992
Creator: Ramsey, W. G.; Jantzen, Carol M. & Taylor, T. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Microwave sintering of titanium diboride

Description: Titanium diboride was heated to high temperatures using microwaves. The highest temperature obtained was 2245/degree/C. Unfortunately, oxidation was a problem, especially at the higher temperatures, although an argon flush and a carbon getter were used. To completely stop oxidation, the oxygen potential must be below 10/sup /minus/18/ atmospheres. Using an argon flush and a carbon getter, titanium diboride was successfully densified to 82% of theoretical without measurable oxidation by heating … more
Date: January 1, 1989
Creator: Katz, J. D.; Blake, R. D. & Scherer, C. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of composition and temperature on viscosity and electrical conductivity of borosilicate glasses for Hanford nuclear waste immobilization

Description: Viscosity and electrical conductivity of 79 simulated borosilicate glasses in the expected range of compositions to be produced in the Hanford Waste Vitrification Plant were measured within the temperature span from 950 to 1250[degree]C. The nine major oxide components were SiO[sub 2], B[sub 2]O[sub 3], Li[sub 2]O, Na[sub 2]O, CaO, MgO, Fe[sub 2]O[sub 3], Al[sub 2]O[sub 3], and ZrO[sub 2]. The test compositions were generated statistically. The data were fitted by Fulcher and Arrhenius equation… more
Date: April 1, 1993
Creator: Hrma, P.; Piepel, G. F.; Smith, D. E.; Redgate, P. E. & Schweiger, M. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Friction of self-lubricating surfaces by ion beam techniques. Final technical report

Description: UES, Inc. conducted a research and development program designed to establish conditions for ion implantation/mixing of suitable additives into the surfaces of bulk ceramics and metals for obtaining self-lubricating low friction and wear characteristics. The substrates considered were ZrO{sub 2}, Al{sub 2}O{sub 3}, Si{sub 3}N{sub 4}, steel and Ni-base superalloy. The lubricant additives chosen were BaF{sub 2}/CaF{sub 2}Ag, MoS{sub 2}, WS{sub 2}and B{sub 2}O{sub 3}. The initial tasks of the progr… more
Date: May 1, 1992
Creator: Bhattacharya, R. S. & Rai, A. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Oil recovery improvement through profile modification by thermal precipitation. Final report, October 1, 1991--August 27, 1993

Description: The objective of this research project has been to investigate the potential for using temperature-dependent (thermal) precipitation of chemicals to reduce the porosity and permeability of porous rocks. The method consists of injecting hot water that is saturated in a chemical that will precipitate upon cooling. Through this process, the permeability of thief zones in oil reservoirs could be reduced, allowing improved recovery by secondary and tertiary recovery processes. The chemical literatur… more
Date: April 1, 1994
Creator: Reis, J. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

First-order model for durability of Hanford waste glasses as a function of composition

Description: Two standard chemical durability tests, the static leach test MCC-1 and product consistency test PCT, were conducted on simulated borosilicate glasses that encompass the expected range of compositions to be produced in the Hanford Waste Vitrification Plant (HWVP). A first-order empirical model was fitted to the data from each test method. The results indicate that glass durability is increased by addition of Al{sub 2}O{sub 3}, moderately increased by addition of ZrO{sub 2} and SiO{sub 2}, and d… more
Date: April 1, 1992
Creator: Hrma, P.; Piepel, G. F.; Schweiger, M. J. & Smith, D. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Advanced method for making vitreous waste forms

Description: A process is described for making waste glass that circumvents the problems of dissolving nuclear waste in molten glass at high temperatures. Because the reactive mixing process is independent of the inherent viscosity of the melt, any glass composition can be prepared with equal facility. Separation of the mixing and melting operations permits novel glass fabrication methods to be employed.
Date: January 1, 1980
Creator: Pope, J. M. & Harrison, D. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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''Glassy'' low temperature thermal properties in crystalline solids

Description: Amorphous dielectrics are known to exhibit anomalous low temperature properties. An extensive review of these properties is presented with an eye toward an understanding of low-lying excitation modes thought to exist in glasses. Work on these systems is described in which a Zr-20 percent Nb samplewhich would be expected to reduce and redistribute the proposed tunneling states. Indeed, the thermal conductivity becomes similar to that of a quenched Zr-8 percent Nb sample and the ''excess'' specif… more
Date: May 1, 1976
Creator: Nathan, B. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Low-frequency nuclear quadrupole resonance with a dc SQUID

Description: Conventional pure nuclear quadrupole resonance (NQR) is a technique well suited for the study of very large quadrupolar interactions. Numerous nuclear magnetic resonance (NMR) techniques have been developed for the study of smaller quadrupolar interactions. However, there are many nuclei which have quadrupolar interactions of intermediate strength. Quadrupolar interactions in this region have traditionally been difficult or unfeasible to detect. This work describes the development and applicati… more
Date: July 1, 1991
Creator: Chang, J. W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

The role of frit in nuclear waste vitrification

Description: Vitrification of nuclear waste requires additives which are often vitrified independently to form a frit. Frit composition is formulated to meet the needs of glass composition and processing. The effects of frit on melter feed and melt processing, glass acceptance, and waste loading is of practical interest in understanding the trade-offs associated with the competing demands placed on frit composition. Melter feed yield stress, viscosity and durability of frits and corresponding waste glasses … more
Date: April 1, 1994
Creator: Vienna, J. D.; Smith, P. A.; Dorn, D. A. & Hrma, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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