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Secondary defects in quenched platinum
The structure of secondary defects in two different platinum purities quenched under ultra high vacuum, has been studied by transmission electron microscopy. Faulted loops on (100) planes have been observed in both materials. In the less pure platinum, Pt B (but purer in terms of carbon content), the defects were observed after quenching, whereas in the purest one, Pt A (but less pure in terms of carbon content), the defects were formed after a long annealing. The Burgers vector of the loops formed after the quenching was a/3 <100> and for loops formed during long annealings, was a/2 <100>, apparently. It was found that in Pt B the loop density increased and the loop size decreased as the quenching temperature was lowered.The same effect was produced by increasing the carbon content by a small amount. The loop formation was totally inhibited by adding a larger amount of carbon and also when the quenching was performed in poor vacuum (approx. 0.01 torr) or in air. The defects can be interpreted as pure vacancy loops heterogeneously nucleated at carbon atom clusters or, as plate like precipitates of carbon atoms and vacancies formed by a co-precipitation mechanism. The discussion of the experimental results …
Date:
November 1, 1979
Creator:
Perez, M.I.
Object Type:
Report
System:
The UNT Digital Library
Hot-gas cleanup system model development. Volume I. Final report
This two-volume report summarizes the state of the art in performance modeling of advanced high-temperature, high-pressure (HTHP) gas cleanup devices. Volume I contains the culmination of the research effort carried over the past 12 months and is a summary of research achievements. Volume II is the user's manual for the computer programs developed under the present research project. In this volume, Section 2 presents background information on pressurized, fluidized-bed combustion concepts, a description of the role of the advanced gas cleanup systems, and a list of advanced gas cleanup systems that are currently in development under DOE sponsorship. Section 3 describes the methodology for the software architecture that forms the basis of the well-disciplined and structured computer programs developed under the present project. Section 4 reviews the fundamental theories that are important in analyzing the cleanup performance of HTHP gas filters. Section 5 discusses the effect of alkali agents in HTHP gas cleanup. Section 6 evaluates the advanced HTHP gas cleanup models based on their mathematical integrity, availability of supporting data, and the likelihood of commercialization. As a result of the evaluation procedure detailed in Section 6, five performance models were chosen to be incorporated into the overall system simulation …
Date:
November 1, 1982
Creator:
Ushimaru, K.; Bennett, A. & Bekowies, P.J.
Object Type:
Report
System:
The UNT Digital Library
System for evaluating the deformation of various materials under compressive loads
None
Date:
November 1, 1975
Creator:
Gallman, R. A.
Object Type:
Report
System:
The UNT Digital Library
Development of mild gasification process
Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.
Date:
November 1, 1987
Creator:
Chu, C.I.C. & Gillespie, B.L.
Object Type:
Report
System:
The UNT Digital Library
Islets of stability beyond period doubling
Period doubling of a periodic orbit of an area preserving map appears to lead to the elimination of all closed invariant curves in the vicinity. We show, however, that there are always islets of stabilhty again beyond the accumulation point of the period doubling sequence.
Date:
November 1, 1981
Creator:
Mackay, R.S.
Object Type:
Report
System:
The UNT Digital Library
Central receiver solar thermal power system, Phase 1. CDRL Item 2. Pilot plant preliminary design report. Volume IV. Receiver subsystem. [10-MW Pilot Plant and 100-MW Commercial Plant]
The conception, design, and testing of the receiver subsystem proposed by the McDonnell Douglas/Rocketdyne Receiver team for the DOE 10-MW Pilot Plant and the 100-MW Commercial Plant are described. The receiver subsystem consists of the receiver unit, the tower on which the receiver unit is mounted above the collector field, and the supporting control and instrumentation equipment. The plans for implementation of the Pilot Plant are given including the anticipated schedule and production plan (procurement, installation, checkout, and maintenance). Specifications for the performance, design, and test requirements for the Pilot Plant receiver subsystem are included. (WHK)
Date:
November 1, 1977
Creator:
Hallet, Jr., R. W. & Gervais, R. L.
Object Type:
Report
System:
The UNT Digital Library
Phase-change thermal energy storage: Final subcontract report
The research and development described in this document was conducted within the US Department of Energy's Solar Thermal Technology Program. The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors or lenses onto a receiver where the solar energy is absorbed as heat and converted into electricity or incorporated into products as process heat. The two primary solar thermal technologies, central receivers and distributed receivers, employ various point and line-focus optics to concentrate sunlight. Current central receiver systems use fields of heliostats (two-axes tracking mirrors) to focus the sun's radiant energy onto a single, tower-mounted receiver. Point focus concentrators up to 17 meters in diameter track the sun in two axes and use parabolic dish mirrors or Fresnel lenses to focus radiant energy onto a receiver. Troughs and bowls are line-focus tracking reflectors that concentrate sunlight onto receiver tubes along their focal lines. Concentrating collector modules can be used alone or in a multimodule system. The concentrated radiant energy …
Date:
November 1, 1989
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Sodium compatibility of HT-9 and Fe-9Cr-1Mo steels
Ferritic steels have been receiving significant attention for possible use as steam generator tubing, and as alternate structural materials for liquid-metal heat-transport systems in commercial fast reactors, fusion reactors, etc. The materials are chosen on the basis of their high thermal conductivity, resistance to stress-corrosion-cracking in aqueous and steam environments, favorable fabricability and fairly low cost. These steels are available in several classes based on the microstructure and alloy content, viz., martensitics, bainitics, delta ferritics, and duplex steels. The low alloy bainitic steels (Fe-2-1/4Cr-1Mo) undergo extensive decarburization when exposed to high temperature flowing sodium. It is for this reason that ferritic steels with higher chromium (9 to 12% Cr) content have been proposed to minimize the carbon transfer and eventual degradation of mechanical properties. The martensitic steels, HT-9 and improved Fe9Cr1Mo are being considered as cladding/duct materials for liquid metal reactors (LMR). The alloy HT-9 is based on 12Cr1Mo composition. The improved Fe9Cr1Mo alloy is based on 9Cr1Mo composition as its name implies. The objective of the work reported here is to evaluate the sodium compatibility of the alloys at temperatures and flow rates typical of LMR cores. Testing was done for 8104 hours at 60/sup 0/C and 3992 hours …
Date:
November 1, 1985
Creator:
Anantatmula, R. P. & Brehm, W. F.
Object Type:
Article
System:
The UNT Digital Library
VUV (vacuum ultraviolet) laser diagnostics of H sup - ion sources
Vacuum ultraviolet laser absorption spectroscopy has been employed to measure the populations and temperatures of ground electronic state H-atoms and vibrationally-excited H{sub 2} molecules in a volume H{sup -} ion source. Measurements of both species have been made under a variety of discharge conditions. Vibrational levels to v{double prime}=8 have been measured, with the vibrational population distribution well described by a temperature of 4150K. 10 refs., 9 figs.
Date:
November 1, 1989
Creator:
Young, A. T.; Stutzin, G. C.; Leung, K. N. & Kunkel, W. B.
Object Type:
Article
System:
The UNT Digital Library
Proceedings of a conference on solar energy for heating greenhouses and greenhouse-residential combinations
Seventeen papers are included. A separate abstract was prepared for each for Energy Research Abstracts (ERA); eight are included in Energy Abstracts for Policy Analysis (EAPA). (MHR)
Date:
November 1, 1977
Creator:
Bond, T E; Godbey, L C & Zornig, H F
Object Type:
Article
System:
The UNT Digital Library
Anaerobic fermentation of simulated in-situ oil shale retort water
The feasibility of removing soluble organics from oil shale retort water by anaerobic digestion with methane production was experimentally investigated. The following conclusions were made. The retort water studied had to be pretreated to remove toxic and add deficient constituents before it could be successfully treated with the anaerobic fermentation process. Pretreatment included pH adjustment to 7, ammonia reduction, and nutrient addition. A digested sludge from a conventional municipal sewage treatment plant was successfully acclimated to the retort water studied. A major fraction of the organics in the retort water studied was stabilized by conversion to CH/sub 4/ and CO/sub 2/ using the anaerobic fermentation process. BOD/sub 5/ and COD removal efficiences were 76 to 80 percent. The effluent from anaerobic fermentation of the retort water studied (BOD/sub 5/ : 530 to 580 mg/l) may be suitable for treatment by conventional aerobic processes. The growth of the methane formers, which stabilize the organics, is nutrient limited in the retort water studied. The pretreatment of the retort water studied removed 49 percent of the BOD/sub 5/. This was probably due to the reduction in solubility of high molecular weight fatty acids at neutral pHs. A major component removed from the retort …
Date:
November 1, 1977
Creator:
Ossio, E. A.; Fox, J. P.; Thomas, J. F. & Poulson, R. E.
Object Type:
Article
System:
The UNT Digital Library
Nuclear chemistry research of high-energy nuclear reactions at Carnegie-Mellon University, 1961--1977. Summary report. [Summaries of research activities at Carnegie-Mellon University]
The activities and the results of research in the study of high energy nuclear reactions carried out at Carnegie Institute of Technology from 1957 to 1967 and at Carnegie-Mellon University from 1967 to 1977 are summarized. A complete list of all publications, doctoral dissertations, and reports resulting from the research of this project is also included. A major part of the report is a review of the research activities and results. The objective of the research of this project was the study of reactions initiated by projectiles of energy above about 100 MeV. The main effort was the investigation of simple nuclear reactions with the objective to deduce reaction mechanisms. These reactions were also used as probes to determine the nuclear structure of the target. In addition, a number of studies of spallation reactions were undertaken which included the determination of excitation functions and recoil properties. Recent research activities which have involved the study of pion induced reactions as well as reactions initiated by heavy ions is also discussed.
Date:
November 1, 1977
Creator:
Caretto, A. A., Jr.
Object Type:
Report
System:
The UNT Digital Library
Polysaccharides and bacterial plugging
Before any successful application of Microbial Enhanced Oil Recovery process can be realized, an understanding of the cells' transport and retentive mechanisms in porous media is needed. Cell transport differs from particle transport in their ability to produce polysaccharides, which are used by cells to adhere to surfaces. Cell injection experiments have been conducted using Leuconostoc cells to illustrate the importance of cellular polysaccharide production as a transport mechanism that hinders cell movement and plugs porous media. Kinetic studies of the Leuconostoc cells, carried out to further understand the plugging rates of porous media, have shown that the cells' growth rates are approximately equal when provided with monosaccharide (glucose and fructose) or sucrose. The only difference in cell metabolism is the production of dextran when sucrose is supplied as a carbon source. Experimentally it has also been shown that the cells' growth rate is weakly dependent upon the sucrose concentration in the media, and strongly dependent upon the concentration of yeast extract. The synthesis of cellular dextran has been found to lag behind cell generation, thus indicating that the cells need to reach maturity before they are capable of expressing the detransucrase enzyme and synthesizing insoluble dextran. Dextran yields were …
Date:
November 1, 1991
Creator:
Fogler, H. S.
Object Type:
Report
System:
The UNT Digital Library
Zero Field Magnetic Properties of Gadolinium Terbium, and Samarium
The mutual inductance or apparent susceptibility due to the presence of the sample in a coaxial inductance coil was observed for Gd, Tb, and Sm in fields of a few gauss over the respective temperature ranges of 78 to 310 deg K, 78 to 235 deg K, and 4.2 to 150 deg K. A paramagnetic Curie point of 284.2 deg K was found for Gd. For Tb, a transition was found which occurred to within 1 deg of the predicted temperature of 220 deg K, and a second peak occurred at 229.4 deg K which is within 2 deg of the heat capacity peak. The 220 deg K peak exhibited hysteresis and time dependence. Extrapolation of Tb data to DELTA M = 0 yielded a Curie point of 235.6 deg K. No hysteresis was observed in the 14.8 deg K peak for Sm. (D.L.C.)
Date:
November 1, 1960
Creator:
Hill, E. D. & Spedding, F. H.
Object Type:
Report
System:
The UNT Digital Library
Advanced energy sources and conversion techniques. Volume 1. [35 papers]
This report addresses the advanced energy sources and conversion techniques.
Date:
November 1, 1958
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Eastern Gas Shales Program. Completion and stimulation of five New York State Energy Research and Development Authority Wells Allegany and Cattaraugus Counties, New York
In order to evaluate the potential of the Devonian Shales as a source of natural gas, DOE/METC in Morgantown, West Virginia, has undertaken the Eastern Gas Shale Program (EGSP); not only to characterize and identify the resource, but also to enhance and improve the productivity of wells completed in the shale. One of the methods used to achieve improved productivity is hydraulic fracturing and, more specifically, foam fracturing. The efforts by DOE/METC included completion and stimulation of five New York State Energy Research and Development Authority (NYSERDA) wells; located in western Allegany County and southwestern Cattaraugus County, New York. The five wells were drilled on high shcool and college properties during the months of June and July 1981. DOE/METC's contribution to the program funded the stimulation and completion of the wells. This work was done under the engineering and field supervision of Gruy Federal, Inc. as contractor to DOE. The completion work took place in the months of July and August 1981. This consisted of running a cement bond log in each well. All logs showed good bonding. This was followed by perforating the Marcellus Shale through the 4-1/2-inch casing. During the next phase, the formation was broken down with …
Date:
November 1, 1981
Creator:
Rdissi, A.
Object Type:
Report
System:
The UNT Digital Library
Mass and energy budgets of animals: Behavioral and ecological implications
The two major aims of our lab are as follows: First, to develop and field-test general mechanistic models that predict animal life history characteristics as influenced by climate and the physical, physiological behavioral characteristics of species. This involves: understanding how animal time and energy budgets are affected by climate and animal properties; predicting growth and reproductive potential from time and energy budgets; predicting mortality based on climate and time and energy budgets; and linking these individual based models to population dynamics. Second to conduct empirical studies of animal physiological ecology, particularly the effects of temperature on time and energy budgets. The physiological ecology of individual animals is the key link between the physical environment and population-level phenomena. We address the macroclimate to microclimate linkage on a broad spatial scale; address the links between individuals and population dynamics for lizard species; test the endotherm energetics and behavior model using beaver; address the spatial variation in climate and its effects on individual energetics, growth and reproduction; and address patchiness in the environment and constraints they may impose on individual energetics, growth and reproduction. These projects are described individually in the following section. 24 refs., 9 figs.
Date:
November 1, 1991
Creator:
Porter, W.P.
Object Type:
Report
System:
The UNT Digital Library
Research and Development of Metal Hydrides. Summary Report for October 1, 1958-September 30, 1960
A detailed study of the fundamental relations in the zirconium -- hydrogen system was made in order to clarify the many points of dispute and to evolve a complete picture describing all phases of this system. An engineering evaluation was made of means for utillzing the various high cross-section metal hydrides in shielding or control applications. These materials would combine the processes of thermalization and absorption. Consequently, they are of considerable interest for use in shielding or controlling epithermal reactors. (auth)
Date:
November 1, 1960
Creator:
Beck, R. L.
Object Type:
Report
System:
The UNT Digital Library
Automatic lead frame plating. Final report
None
Date:
November 1, 1975
Creator:
Jarboe, D.M.
Object Type:
Report
System:
The UNT Digital Library
Neutronics of a mixed-flow gas-core reactor
The study was made to investigate the neutronic feasibility of a mixed-flow gas-core reactor. Three reactor concepts were studied: four- and seven-cell radial reactors and a seven-cell scallop reactor. The reactors were fueled with UF/sub 6/ (either U-233 or U-235) and various parameters were varied. A four-cell reactor is not practical nor is the U-235 fueled seven-cell radial reactor; however, the 7-cell U-233 radial and scallop reactors can satisfy all design criteria. The mixed flow gas core reactor is a very attractive reactor concept and warrants further investigation.
Date:
November 1, 1977
Creator:
Soran, P. D. & Hansen, G. E.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of Hydrocarbon Diluents for the Purex Process
Forty-nine hydrocarbon products were evaluated in the laboratory in a search for a highly stable diluent for the organic extractant used in a radiochemical separations plant. The formation of zirconium ligands during chemical and radiolytic degradation increased with boiling point for isoparaffinic producte but was approximately constant for n-parafiins. Of those materials that met the local flash point specification, the n-parafiins were superior. (auth)
Date:
November 1, 1961
Creator:
Dennis, B. P. & West, D. L.
Object Type:
Report
System:
The UNT Digital Library
Theoretical modeling and experimental characterization of planar defects in Y sub 2 Ba sub 4 Cu sub 6+x O sub 14+x
Crystallographic defects and phase transformations in the system Y{sub 2}Ba{sub 4}Cu{sub 6 + x}O{sub 14 + x}(0{le}{times}{le}4) are investigated by high resolution transmission electron microscopy (TEM) and static lattice, three dimensional Monte Carlo computer simulations. High resolution images of partially transformed (x = 2 to x = 1) material reveal a prevalence of CuO planar defects (stacking faults) associated with the transformation and an absence of disturbance to the perovskite Ba-Y-Ba blocks. An atomic mechanism involving the intercalculation and removal of extra CuO planes by partial dislocation climb, and requiring only a-b plane diffusion, is developed for the formation of such planar defects during changes in the layered YBaCuO crystal structure. Monte Carlo simulations based on the proposed transformation mechanism accurately reproduce the observed defects and known equilibrium structures. 24 refs., 4 figs.
Date:
November 1, 1990
Creator:
Burmester, C. P.; Fendorf, M.; Gronsky, R. & Wille, L. T.
Object Type:
Article
System:
The UNT Digital Library
Framework for control system development
Control systems being developed for the present generation of accelerators will need to adapt to changing machine and operating state conditions. Such systems must also be capable of evolving over the life of the accelerator operation. In this paper we present a framework for the development of adaptive control systems.
Date:
November 1, 1991
Creator:
Cork, C. & Nishimura, Hiroshi.
Object Type:
Article
System:
The UNT Digital Library
Motion of a Loosely Fitting Piston in a Closed End Cylinder Containing a Perfect Gas
The equations of motion are derived for a piston in a closed end cylinder containing a compressible perfect gas. These equations include the possibility of an arbitrary motion imposed on the cylinder. In the analysis, it is assumed that there is a clearance between the piston and the cylinder which is sufficiently small so that the flow in the gap is controlled by viscous forces.
Date:
November 1, 1975
Creator:
Stone, G. W.; Reis, G. E. & Kaestner, P. C.
Object Type:
Report
System:
The UNT Digital Library