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High temperature ceramic membrane reactors for coal liquid upgrading

Description: In this project we intend to study a novel process concept, i.e, the use of ceramic membranes reactors in upgrading of coal derived liquids. Membrane reactors have been used in a number of catalytic reaction processes in order to overcome the limitations on conversion imposed by thermodynamic equilibrium. They have, furthermore, the inherent capability for combining reaction and separation in a single step. Thus they offer promise for improving and optimizing yield, selectivity and performance … more
Date: January 1, 1992
Creator: Tsotsis, T.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Repair Welding of Fusion Reactor Components

Description: Recent experimental investigations indicate that the repair welding of irradiated materials containing greater than 1 to 2.5 appm helium leads to catastrophic cracking in the heat affected zone of the weld. The high temperatures and cooling tensile stresses which occur during the welding process lead to enhanced helium bubble growth in the heat affected zone region, resulting in catastrophic cracking upon cooling. An investigation is proposed which seeks to determine the effect of stress state … more
Date: May 20, 1992
Creator: Chin, Bryan A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(The relationship between microstructure and magnetic properties in high-energy permanent magnets characterized by polytwinned structures)

Description: This report summarizes the results of a study of the relationship between microstructure and magnetic properties in a unique genre of ferromagnetic material characterized by a polysynthetically twinned structure which arises during solid state transformation. These results stem from the work over a period of approximately 27 months of a nominal 3 year grant period. The report also contains a proposal to extend the research project for an additional 3 years. The polytwinned structures produce an… more
Date: January 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High temperature ceramic membrane reactors for coal liquid upgrading

Description: In this project we will study a novel process concept, i.e., the use of ceramic membrane reactors in upgrading of coal model compounds and coal derived liquids. In general terms, the USC research team is responsible for constructing and operating the membrane reactor apparatus and for testing various inorganic membranes for the upgrading of coal derived asphaltenes and coal model compounds. The USC effort will involve the principal investigator of this project and two graduate research assistan… more
Date: January 1, 1992
Creator: Tsotsis, T.T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Milliwatt Generator Project

Description: This report covers progress on the Milliwatt Generator Project from April 1986 through March 1988. Activities included fuel processing and characterization, production of heat sources, fabrication of pressure-burst test units, compatibility studies, impact testing, and examination of surveillance units. The major task of the Los Alamos Milliwatt Generator Project is to fabricate MC2893A heat sources (4.0 W) for MC2730A radioisotope thermoelectric generators (RTGS) and MC3599 heat sources (4.5 W… more
Date: May 1, 1992
Creator: Latimer, T.W. & Rinehart, G.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3

Description: A method is described for obtaining monodomain PbTiO{sub 3} single crystals with high electrical resistivity (10{sup 10}{Omega} cm) and low dielectric frequency dispersion. The single crystals of PbTiO{sub 3} were grown by flux solution method. Space charge related defects, which result in the large dielectric frequency dispersion, were eliminated by heat treatments. 90{degrees} domains were removed by applying a unidirectional compressive stress along the <100> crystallographic direction. The … more
Date: May 1, 1992
Creator: Li, Z.; Xu, X. Z.; Dai, X. H.; Lam, D. J. & Chan, S. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods

Description: The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of rela… more
Date: February 1, 1992
Creator: Kirshnan, K.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Surfaces and Thin Films Studied by Picosecond Ultrasonics

Description: This research is the study of thin films and interfaces via the use of the picosecond ultrasonic technique. In these experiments ultrasonic waves are excited in a structure by means of a picosecond light pulse ( pump pulse''). The propagation of these waves is detected through the use of a probe light pulse that is time-delayed relative to the pump. This probe pulse measures the change {Delta}R(t) in the optical reflectivity of the structure that occurs because the ultrasonic wave changes the o… more
Date: May 1, 1992
Creator: Maris, J. H. & Tauc, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A design of experiment study of plasma sprayed alumina-titania coatings

Description: An experimental study of the plasma spraying of alumina-titania powder is presented in this paper. This powder system is being used to fabricate heater tubes that emulate nuclear fuel tubes for use in thermal-hydraulic testing. Coating experiments were conducted using a Taguchi fractional-factorial design parametric study. Operating parameters were varied around the typical spray parameters in a systematic design of experiments in order to display the range of plasma processing conditions and t… more
Date: January 1, 1992
Creator: Steeper, T. J. (Du Pont de Nemours (E.I.) and Co., Aiken, SC (United States). Savannah River Lab.); Varacalle, D. J. Jr.; Wilson, G. C. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Riggs, W. L. II (Tubal Cain Co., Loveland, OH (United States)); Rotolico, A. J. & Nerz, J. E. (Metco/Perkin-Elmer, Westbury, NY (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanical strength and stability of lithium aluminate

Description: Pacific Northwest Laboratory (PNL) investigated the strength and resistance to thermal shock of lithium aluminate annular pellets. The room temperature, axial compressive fracture strength of pellets made at Westinghouse Advanced Energy Systems (WAES) varied from 80 to 133 ksi. The strength at 430{degrees}C (806{degrees}F) was to 30 to 40% lower. The strength at 900{degrees}C (1652{degrees}F) showed a wide variation with one measurement near 90 ksi. These strength values are consistent with oth… more
Date: June 1, 1992
Creator: Brimhall, J.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Celotex trademark charring depths in the DT-18 shipping container

Description: Celotex {trademark}, the insulating material used between the outer and inner containers of the DT-18 shipping package, undergoes decomposition, combustion, or both when heated to temperatures exceeding 150{degrees}C. Several DT-18 packages that had previously undergone hypothetical thermal accident testing were opened and Celotex {trademark} charring depths ranging from {1/2} to 1 {1/2} in. were recorded. The majority of char depth data taken was between 3/4 and 1 {1/4} in. One-dimensional HEA… more
Date: March 1, 1992
Creator: Anderson, J.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Edge-on ion irradiation of electron microscope specimens

Description: A special technique is described for in situ transmission electron microscope (TEM) experiments involving simultaneous ion irradiation, in which the resultant phenomena are observed as in a cross-section TEM specimen. That is, instead of ion-irradiating the film or foil specimen normal to the major surfaces and observing in plan view (i.e., in the same direction), the specimen is irradiated edge-on (i.e., parallel to the major surfaces) and is observed normal to the depth direction with respect… more
Date: January 1, 1992
Creator: Otero, M. P. & Allen, C. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electronic and structural properties of metallic microclusters

Description: The first part of this thesis presents a first-order pseudopotential calculation at T=O of the total energy of small sodium clusters of size N<800. The calculation is based on a local-pseudopotential scheme and local-density correlation and exchange. A temperature-size (T-N) phase-diagram is then derived using the T=O results and Lindemann's criterion for melting. The phase-diagram contains three regions of stability: (1) a liquid (jellium) phase at temperatures above the melting line T{sub M}(… more
Date: April 1, 1992
Creator: Maiti, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991

Description: The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. … more
Date: April 1, 1992
Creator: Judkins, R.R. & Cole, N.C. (comps.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal strains in titanium aluminide and nickel aluminide composites

Description: Neutron diffraction was used to measure residual thermal strains developed during postfabrication cooling in titanium aluminide and nickel aluminide intermetallic matrix composites. Silicon carbide /Ti 14Al-21Nb, tungsten and sapphire/NiAl, and sapphire and SiC-coated sapphire/NiAl{sub 25}Fe{sub 10} composites were investigated. The thermal expansion coefficient of the matrix is usually greater than that of the fibers. As such, during cooldown, compressive residual strains are generated in the … more
Date: January 1, 1992
Creator: Saigal, A. (Tufts Univ., Medford, MA (United States). Dept. of Mechanical Engineering) & Kupperman, D.S. (Argonne National Lab., IL (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Weld Penetration and Defect Control

Description: Highly engineered designs increasingly require the use of improved materials and sophisticated manufacturing techniques. To obtain optimal performance from these engineered products, improved weld properties and joint reliability are a necessarily. This requirement for improved weld performance and reliability has led to the development of high-performance welding systems in which pre-programmed parameters are specified before any welding takes place. These automated systems however lack the ab… more
Date: May 15, 1992
Creator: Chin, Bryan A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of particle rebound characteristics and material erosion at high temperature

Description: In this research an investigation was conducted to study the ash particle rebound characteristics and the associated erosion behavior of alloys and coatings which are widely used in gas and steam turbines. A three-component LDV system was used to measure the restitution parameters of 15 micron mean diameter coal ash particles impacting superalloys and coating at different angles. The presented results show the variation of the particle restitution ratios with the impingement angle for the coate… more
Date: April 1, 1992
Creator: Tabakoff, W.; Hamed, A.; Metwally, A. & Yeuan, J. (Cincinnati Univ., OH (United States). Dept. of Aerospace Engineering and Engineering Mechanics)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent advances in high-temperature superconductor wire fabrication and applications development

Description: In this paper, recent advances in fabrication of HTS wires are summarized, and detailed discussion is provided for developments in near- and intermediate-term applications. Near-term applications, using presently obtainable current densities, include: liquid-nitrogen depth sensors, cryostat current leads, and magnetic bearings. Intermediate-term applications, using current densities expected to be available in the near future include fault-current limiters and short transmission lines. 25 refs.
Date: January 1, 1992
Creator: Hull, J.R. & Uherka, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Optimization of film synthesized rare earth transition metal permanent magnet systems

Description: Progress is reported in three areas: high coercivity Sm-Fe-Ti-V, Sm-Fe-Zr, and two element Sm-Fe Sm{sub 5}(Fe,T){sub 17} type crystalline phases; ThMn{sub 12} type pseudobinary SmFe{sub 12-x}T{sub x}(0{le}{times}{le}1.5); and sputter process control for the synthesis of precisely textured rare earth-transition metal magnetic films. (DLC)
Date: January 1, 1992
Creator: Cadieu, F.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlinear, distortive phenomena in solids: Martensitic, crack, and multiscale structures

Description: This ongoing program, from the beginning of the first three year grant 1988--1991 and now in the first year of the second phase 1991--1994, has been directed at developing both an understanding of the physics underlying structural transformations in real (alloy) materials as well as new theoretical methods which adequately describe the large (nonlinear) distortions which characterize such processes. We have had a particular interest in martensitic systems, first (1988--1991) in the equilibrium … more
Date: January 1, 1992
Creator: Krumhansl, J. A. & Sethna, J. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of nondestructive evaluation methods and prediction of effects of flaws on the fracture behavior of structural ceramics

Description: Characterization of ceramic matrix composites (continuous and whisker-type) by nondestructive evaluation (NDE) methods and an understanding of fracture behavior, together with correlation of fracture and NDE data, may provide insight into the prediction of component performance and the development of process technology. Knowledge of the degradation extent of fiber tows or monofilament degradation after processing, extent of open porosity before densification, and filament/fiber alignments befor… more
Date: May 1, 1992
Creator: Ellingson, W.A.; Singh, J.P.; Holloway, D.L.; Dieckman, S.L.; Singh, D.; Sivers, E.A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Poly(lactic acid) degradable plastics, coatings, and binders

Description: Biochemical processes to derive value from the management of high carbohydrate food wastes, such as potato starch, corn starch, and cheese whey permeate, have typically been limited to the production of either ethanol or methane. Argonne National Laboratory (ANL) believes that lactic acid presents an attractive option for an alternate fermentation end product, especially in light of lactic acids' being a viable candidate for conversion to environmentally safe poly(lactic acid) (PLA) degradable … more
Date: January 1, 1992
Creator: Bonsignore, P.V.; Coleman, R.D. & Mudde, J.P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Materials compatibility and lubricants research on CFC-refrigerant substitutes: Thermophysical properties

Description: Numerous fluids have been identified as promising alternative refrigerants, but much of the information needed to predict their behavior as pure fluids and as components in mixtures does not exist. In particular, reliable thermophysical properties data and models are needed to predict the performance of the new refrigerants in heating and cooling equipment, and to design and optimize equipment to be reliable and energy efficient. The objective of this project is to provide highly accurate, sele… more
Date: April 1, 1992
Creator: Kayser, R.F. (National Inst. of Standards and Technology, Gaithersburg, MD (United States). Thermophysics Div.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Time-dependent behavior of concrete

Description: This paper is a condensed version of the material presented at the International Workshop on Finite Element Analysis of Reinforced Concrete, Session 4 -- Time Dependent Behavior, held at Columbia University, New York on June 3--6, 1991. Dr. P.A. Pfeiffer presented recent developments in time-dependent behavior of concrete and Professor T. Tanabe presented a review of research in Japan on time-dependent behavior of concrete. The paper discusses the recent research of time-dependent behavior of c… more
Date: January 1, 1992
Creator: Pfeiffer, P.A. (Argonne National Lab., IL (United States)) & Tanabe, Tada-aki (Nagoya Univ. (Japan). Dept. of Civil Engineering)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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