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in subjects: "Crystallization"  
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Study of rock-water-nuclear waste interactions in the Pasco Basin, Washington. Part I. Distribution and composition of secondary and primary mineral phases in basalts of the Pasco Basin, Washington

Description: In Part I of this report the results of Task III are presented and discussed. The subject of Task III is the study and identification of secondary and primary mineral assemblages in basalts of the Pasco Basin of southeastern Washington. In particular, we have determined the relative amounts, crystallization sequence, and compositions of secondary minerals found lining vesicle and fracture surfaces. This information, together with data on the chemical composition of primary minerals and the exte… more
Date: September 1, 1979
Creator: Benson, L. V. & Teague, L. S.
Partner: UNT Libraries Government Documents Department
open access

Variations in volatiles in magma bodies based on studies of melt inclusions

Description: Knowledge of volatile concentrations in magmas are important in the prediction of explosive volcanism, and contribute to the understanding of the carbon dioxide budget of the atmosphere. Some important variables that are controlled by volatiles are: crystallization temperature of phases, composition of liquids minimum, and viscosity. Volatiles are also catalysts for reactions.
Date: June 15, 1989
Creator: Vogel, T. A.
Partner: UNT Libraries Government Documents Department
open access

Design, microstructure, and high-temperature behavior of silicon nitride sintered with rate-earth oxides

Description: The processing-microstructure-property relations of silicon nitride ceramics sintered with rare-earth oxide additives have been investigated with the aim of improving their high-temperature behavior. The additions of the oxides of Y, Sm, Gd, Dy, Er, or Yb were compositionally controlled to tailor the intergranular phase. The resulting microstructure consisted of {beta}-Si{sub 3}N{sub 4} grains and a crystalline secondary phase of RE{sub 2}Si{sub 2}O{sub 7}, with a thin residual amorphous phase … more
Date: August 1, 1991
Creator: Ciniculk, M.K. (California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering)
Partner: UNT Libraries Government Documents Department
open access

X-ray scattering studies of non-equilibrium ordering processes

Description: This report summarizes the major results obtained under US DOE Grant Number FG05-90ER45280 from the dates November 1, 1989 through October 31, 1992 inclusive. The principal work includes x-ray scattering studies of phase transition kinetics in binary alloy order-disorder transitions, block co-polymer crystallization, and charge density wave solids under applied electric fields, and studies of magnetic excitations in low dimensional quantum systems.
Date: January 1, 1992
Creator: Nagler, S.E.
Partner: UNT Libraries Government Documents Department
open access

CsAlSi/sub 5/O/sub 12/: a possible host for /sup 137/Cs immobilization

Description: CsAlSi/sub 5/O/sub 12/ exhibits more acid resistance than pollucite (CsAlSi/sub 2/O/sub 6/). At pH values of 1.02 and 1.40, the extraction of Cs from CsAlSi/sub 5/O/sub 12/ at 25/sup 0/C was approximately proportional to the square root of leach time. The Cs extraction at 25/sup 0/C varied as (H/sup +/)/sup 0/ /sup 36/ over the pH range of 1 to 6. Also, the Cs extraction in various brines at 300/sup 0/C/30 MPa was comparable with that for pollucite. CsAlSi/sub 5/O/sub 12/ can be crystallized at… more
Date: March 31, 1982
Creator: Adl, T. & Vance, E.R.
Partner: UNT Libraries Government Documents Department
open access

Effect of processing conditions on the reliability of cross-linked polyethylene cable insulation. First year report

Description: Progress is reported in crystallization and morphology, treed cables, and cable production on the reliability of cross-linked polyethylene cable insulation. Scanning electron microscopy of polished surfaces etched with carbon tetrachloride vapor, differential scanning calorimetry and x-ray diffraction were used for morphological investigations until recently when good results have been obtained using the technique of permanganic acid etching. (FS)
Date: unknown
Creator: Phillips, P.J.
Partner: UNT Libraries Government Documents Department
open access

EXPERIMENTAL ATTEMPTS TO STABILIZE A CUBIC FORM OF BeO

Description: Binary mixtures of BeO with the oxides Al/sub 2/O/sub 3/, CaO, Li/sub 2/ O, MgO, Sc/sub 2/O/sub 3/, TiO/sub 2/, Y/sub 2/O/sub 3/, and ZrO/sub 2/ were fired to temperatures in excess of 2050 deg C in an attempt to produce a stabilized cubic crystalline modification of BeO. No evidence was observed in microscopic and x-ray diffraction analyses of the cooled specimens that a cubic form of BeO had formed in the experiment. (auth)
Date: December 22, 1961
Creator: Thoma, R.E.; Friedman, H.A. & McVay, T.N.
Partner: UNT Libraries Government Documents Department
open access

Investigation of a fossil geothermal system, Hamblin-Cleopatra Volcano, Clark County, Nevada. Final technical report

Description: The Hamblin-Cleopatra volcano, selected for study because erosion and fault displacement have exposed the entire volcanic succession, the intrusive core, a radial dike systems, and sedimentary and volcanic rocks that predate and postdate the volcano, was investigated to estimate the proportions of igneous materials forming lava flows, pyroclastic deposits, intrusive bodies, and reworked debris. Chemical changes in the magma throughout the active period of the volcano were documented. The geothe… more
Date: July 28, 1986
Creator: Barker, D.S.
Partner: UNT Libraries Government Documents Department
open access

The thermodynamic properties of benzothiazole and benzoxazole

Description: This research program, funded by the Department of Energy, Office of Fossil Energy, Advanced Extraction and Process Technology, provides accurate experimental thermochemical and thermophysical properties for key'' organic diheteroatom-containing compounds present in heavy petroleum feedstocks, and applies the experimental information to thermodynamic analyses of key hydrodesulfurization, hydrodenitrogenation, and hydrodeoxygenation reaction networks. Thermodynamic analyses, based on accurate in… more
Date: August 1, 1991
Creator: Steele, W. V.; Chirico, R. D.; Knipmeyer, S. E. & Nguyen, A.
Partner: UNT Libraries Government Documents Department
open access

Secondary minerals found in the cores DC2 A1 and DC2 A2 taken from the Grande Ronde Basalt Formation, Pasco Basin, Washington

Description: The results obtained for Task I are presented and discussed in this report. The subject of Task I is the study and identification of secondary mineral assemblages in two slant cores drilled off core DC2. The data were obtained from scanning electron microscopic (SEM/EDAX), x-ray diffraction (XRD), and thin section petrographic studies. In addition, an attempt was made to determine the lateral continuity of the secondary mineralization and the extent to which the fissures in this potential repos… more
Date: January 1, 1980
Creator: Teague, L.S.
Partner: UNT Libraries Government Documents Department
open access

PHYSICAL METALLURGY OF FAST BREEDER REACTOR CLADDING MATERIALS AND REFRACTORY METALS.

Description: Studies on Re - Mo - W alloys led to lower cost production procedures and greatly improved room temperature ductility properties of powder metallurgy materials used for fast breeder reactor fuel cladding materials. Data are presented for ductility, grain size, hardness, recrystallization, and changes in aging at temperatures up to 2000 deg C for periods up to 1000 hrs. (F.S.)
Date: October 31, 1969
Creator: Collins, C.G. & Bohlander, K.M.
Partner: UNT Libraries Government Documents Department
open access

POSSIBLE IMPLICATIONS OF THE DAMAGE BY RADIATION IN THE STORAGE OF PROPELLANTS IN OUTER SPACE AND TENTATIVE METHODS FOR ITS MEASUREMENT

Description: The damage by radiation that can be expected during the storage of H/sub 2/-bonded propellants in outer space is analyzed in terms of the available data on radiation levels. On this basis, the alternatives of storing the propellants as liquids or as solids, at low temperature, are discussed, and account is taken of recent results on their thermal behavior. Vitreous aggregation states of compounds that could crystallize spontaneously after long periods of irradiation are shown to present some ha… more
Date: July 1, 1962
Creator: McMillan, J.A.
Partner: UNT Libraries Government Documents Department
open access

Fundamental studies of the mechanisms of slag deposit formation: Final report

Description: The kinetics of ash deposition on utility boilers have been studied. A heated tube furnace system was used in the study. Areas of consideration in the deposition mechanics were: close space knowledge of chemical composition and distribution of inorganic constituents in coal, transformations and reactions of the inorganic constituents in the flame, ash transport mechanisms, initial adhesion of ash particles to heat transfer surfaces and subsequently to each other to form a deposit, and further i… more
Date: July 1, 1987
Creator: Austin, L.G.; Benson, S.; Rabinovich, A.; Tangsathitkulchai, M. & H.H., Schobert
Partner: UNT Libraries Government Documents Department
open access

Effects of processng conditions on the reliability of cross-linked polyethylene cable insulation. Progress report

Description: The overall long-term objective of the program remains the determination of the influence of processng on the electrical properties of cross-linked polyethylenes through its effect on morphological variables. Although aimed at an understanding of failure processes in heavy walled insulation, the basic morphological studies are of direct relevance to the many varieties of cross-linked polyethylenes now becoming amongst the most reliable of engineering plastics. There are three basic studies invo… more
Date: January 1, 1982
Creator: Phillips, P.J.
Partner: UNT Libraries Government Documents Department
open access

Modeling of silicon particle growth. Progress report

Description: Efforts at the Jet Propulsion Laboratory toward the production of pure polycrystaline silicon are centered on the concept of silicon particle growth in a fluidized bed reactor (FBR) and a continuous flow pyrolyzer (CFP). The CFP possibly can provide the seed particles which will be grown to larger sizes in the FBR. In both the reactors polycrystalline silicon is obtaned from the pyrolysis of silane. A part of the JPL effort is to develop a model of silicon particle growth for the purpose of pre… more
Date: April 15, 1979
Creator: Praturi, A.K.; Hsu, G.C. & Lutwack, R.
Partner: UNT Libraries Government Documents Department
open access

Properties of Kel F-800 polymer

Description: Kel F-800 fluorocarbon polymer has been selected as the binder for the TATB explosive in the B77 bomb. Kel F-800 is a 3M copolymer derived from the monomers chlorotrifluorethylene (CTFE) and vinylidine fluoride (VF/sub 2/). To understand and define Kel F-800 in relation to its intended use, as well as to generate guidelines for controlling the WR material, a thorough evaluation of its properties and the expected variations from different production lots was made. The research showed that Kel F-… more
Date: July 21, 1977
Creator: Cady, W.E. & Caley, L.E.
Partner: UNT Libraries Government Documents Department
open access

Annual report Development and characterization of solidified forms for high-level wastes: 1978.

Description: Development and characterization of solidified high-level waste forms are directed at determining both process properties and long-term behaviors of various solidified high-level waste forms in aqueous, thermal, and radiation environments. Waste glass properties measured as a function of composition were melt viscosity, melt electrical conductivity, devitrification, and chemical durability. The alkali metals were found to have the greatest effect upon glass properties. Titanium caused a slight … more
Date: December 1, 1979
Creator: Ross, W. A. & Mendel, J. E.
Partner: UNT Libraries Government Documents Department
open access

Phenomenological model for transient deformation based on state variables

Description: The state variable theory of Hart, while providing a unified description of plasticity-dominated deformation, exhibits deficiencies when it is applied to transient deformation phenomena at stresses below yield. It appears that the description of stored anelastic strain is oversimplified. Consideration of a simple physical picture based on continuum dislocation pileups suggests that the neglect of weak barriers to dislocation motion is the source of these inadequacies. An appropriately modified … more
Date: unknown
Creator: Jackson, M. S.; Cho, C. W.; Alexopoulos, P.; Mughrabi, H. & Li, C. Y.
Partner: UNT Libraries Government Documents Department
open access

FRACTIONAL CRYSTALLIZATION FEED ENVELOPE

Description: Laboratory work was completed on a set of evaporation tests designed to establish a feed envelope for the fractional crystallization process. The feed envelope defines chemical concentration limits within which the process can be operated successfully. All 38 runs in the half-factorial design matrix were completed successfully, based on the qualitative definition of success. There is no feed composition likely to be derived from saltcake dissolution that would cause the fractional crystallizati… more
Date: March 19, 2008
Creator: DL, HERTING
Partner: UNT Libraries Government Documents Department
open access

INTERNATIONAL STUDY OF ALUMINUM IMPACTS ON CRYSTALLIZATION IN U.S. HIGH LEVEL WASTE GLASS

Description: The objective of this task was to develop glass formulations for (Department of Energy) DOE waste streams with high aluminum concentrations to avoid nepheline formation while maintaining or meeting waste loading and/or waste throughput expectations as well as satisfying critical process and product performance related constraints. Liquidus temperatures and crystallization behavior were carefully characterized to support model development for higher waste loading glasses. The experimental work, … more
Date: September 23, 2008
Creator: Fox, K; David Peeler, D; Tommy Edwards, T; David Best, D; Irene Reamer, I; Phyllis Workman, P et al.
Partner: UNT Libraries Government Documents Department
open access

REFINEMENT OF THE NEPHELINE DISCRIMINATOR: RESULTS OF A PHASE II STUDY

Description: Twenty five glass compositions were selected for a Phase II study to assess the potential for reducing the conservatism in the nepheline discriminator. The glass compositions were restricted to regions that fell within the validation ranges of the DWPF PCCS models. In addition, the liquidus temperature model was used to restrict the glass compositions so that they could all be melted at the same temperature. The nepheline discriminator was used to force the glass compositions into regions where… more
Date: November 21, 2008
Creator: Fox, K & Tommy Edwards, T
Partner: UNT Libraries Government Documents Department
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