Degree Department

7,064 Matching Results

Results open in a new window/tab.

1/2 Sintering of Mullite-Containing Materials: I. Effect of Composition (open access)

1/2 Sintering of Mullite-Containing Materials: I. Effect of Composition

Sintering behavior of mullite-containing powders was studied over a range of chemical compositions (Al{sub 2}O{sub 3}/SiO{sub 2} ratio). Densification measurements were made for both liquid phase-containing and solid state systems. Small amounts of liquid phase were observed to have a significant effect on densification rate. A linear relationship was obtained between the percent of theoretical density and the logarithm of time for compositions in the range 73-75 wt% Al{sub 2}O{sub 3}. Currently available models for intermediate stage sintering kinetics were considered to be inadequate for these systems. Grain boundary transport 0r diffusion appeared to be the primary mechanism of densification.
Date: December 1, 1981
Creator: Sacks, Michael D. & Pask, Joseph A.
Object Type: Article
System: The UNT Digital Library
3. 6 simplified methods for design (open access)

3. 6 simplified methods for design

Simplified design analysis methods for elevated temperature construction are classified and reviewed. Because the major impetus for developing elevated temperature design methodology during the past ten years has been the LMFBR program, considerable emphasis is placed upon results from this source. The operating characteristics of the LMFBR are such that cycles of severe transient thermal stresses can be interspersed with normal elevated temperature operational periods of significant duration, leading to a combination of plastic and creep deformation. The various simplified methods are organized into two general categories, depending upon whether it is the material, or constitutive, model that is reduced, or the geometric modeling that is simplified. Because the elastic representation of material behavior is so prevalent, an entire section is devoted to elastic analysis methods. Finally, the validation of the simplified procedures is discussed.
Date: January 1, 1981
Creator: Nickell, R.E. & Yahr, G.T.
Object Type: Article
System: The UNT Digital Library
3-D Nonlinear Calculations of Resistive Tearing Modes (open access)

3-D Nonlinear Calculations of Resistive Tearing Modes

Recent numerical calculations of the evolution of resistive tearing modes have been central to the understanding of magnetohydrodynamic activity and disruptions in tokamaks. The nonlinear, 3-D, initial-value computer code RSF has provided many of these results. This code assumes cylindrical geometry with a Fourier series representation in the two periodic coordinates and a finite-difference representation in the radial direction. This choice makes RSF considerably more accurate and efficient than previous codes.
Date: March 1, 1981
Creator: Hicks, H. R.; Holmes, J. A.; Lee, D. K.; Carreras, B. & Waddell, B. V.
Object Type: Report
System: The UNT Digital Library
T-3 electron-beam-excited laser system (open access)

T-3 electron-beam-excited laser system

A laser system specifically designed to study the kinetics of electron-beam driven systems is described. Details of the system are given along with measurements of the electron-beam uniformity and deposition in the laser medium. Some HF laser results obtained with this system are also given.
Date: February 1, 1981
Creator: Klein, R. A.
Object Type: Report
System: The UNT Digital Library
3-megajoule heavy-ion fusion driver (open access)

3-megajoule heavy-ion fusion driver

The initiation of inertial confinement fusion reactions with a heavy ion particle beam has been under intensive study since 1976, and the progress of this study is principally documented in the proceedings of annual workshops held by US National Laboratories. At this time a 3MJ, 150 TW, ion beam is a good choice to initiate microexplosions with energy gain of 100. The Lawrence Berkeley Laboratory has made systems studies based on a Linear Induction Accelerator to meet the beam requirements. The accelerator system, expected performance and cost, and technical problems to be addressed in the near future are discussed.
Date: June 1, 1981
Creator: Faltens, A.; Hoyer, E. & Keefe, D.
Object Type: Article
System: The UNT Digital Library
10-joule high-voltage trigger micro Marx (open access)

10-joule high-voltage trigger micro Marx

A low energy Marx generator makes a convenient trigger for various spark gaps. With an output around 200 kV and a risetime less than 2 ns, the micro-Marx can multichannel field distortion gaps or fire a number of gaps without much gap-to-gap isolation. This design features small size, low cost, and good triggering characteristics. The complete unit is shown.
Date: January 1, 1981
Creator: Platts, D. A.
Object Type: Article
System: The UNT Digital Library
10-kA pulsed power supply for superconducting coils (open access)

10-kA pulsed power supply for superconducting coils

A new 4-MW inductor-converter bridge (ICB) for supplying power to pulsed superconducting magnets is under construction at Argonne National Laoratory. This is a second-generation ICB built at Argonne Lab. The analytical, design, and control techniques developed for the first prototype have been used in the design of the new system. The paper presents the important considerations in the design of the new ICB. A brief description of the operation of the circuit is also given.
Date: January 1, 1981
Creator: Ehsani, M.; Fuja, R. E. & Kustom, R. L.
Object Type: Article
System: The UNT Digital Library
10-MWe solar-thermal central-receiver pilot plant, solar facilities design integration: collector-field optimization report (RADL item 2-25) (open access)

10-MWe solar-thermal central-receiver pilot plant, solar facilities design integration: collector-field optimization report (RADL item 2-25)

Appropriate cost and performance models and computer codes have been developed to carry out the collector field optimization, as well as additional computer codes to define the actual heliostat locations in the optimized field and to compute in detail the performance to be expected of the defined field. The range of capabilities of the available optimization and performance codes is described. The role of the optimization code in the definition of the pilot plant is specified, and a complete description of the optimization process itself is given. The detailed cost model used by the optimizer for the commercial system optimization is presented in the form of equations relating the cost element to each of the factors that determine it. The design basis for the commercial system is presented together with the rationale for its selection. The development of the individual heliostat performance code is presented. Use of the individual heliostat code in a completed study of receiver panel power under sunrise startup conditions is described. The procedure whereby performance and heliostat spacing data from the representative commercial-scale system are converted into coefficients of use in the layout processor is described, and the actual procedure used in the layout processor is …
Date: January 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
20-kW Solar Photovoltaic Flat-Panel Power System for an Uninterruptible Power-System Load in El Paso, Texas. Phase Ii. System Fabrication. Final Report October 1, 1979-May 31, 1981 (open access)

20-kW Solar Photovoltaic Flat-Panel Power System for an Uninterruptible Power-System Load in El Paso, Texas. Phase Ii. System Fabrication. Final Report October 1, 1979-May 31, 1981

The system plans, construction, integration and test, and performance evaluation are discussed for the photovoltaic power supply at the Newman Power Station in El Paso, Texas. The system consists of 64 parallel-connected panels, each panel containing nine series-connected photovoltaic modules. The system is connected, through power monitoring equipment, to an existing DC bus that supplies uninterruptible power to a computer that controls the power generating equipment. The site is described and possible environmental hazards are assessed. Site preparation and the installation of the photovoltaic panels, electrical cabling, and instrumentation subsystems are described. System testing includes initial system checkout, module performance test, control system test. A training program for operators and maintenance personnel is briefly described, including visual aids. Performance data collection and analysis are described, and actual data are compared with a computer simulation. System drawings are included. (LEW)
Date: December 1, 1981
Creator: Risser, V.V.
Object Type: Report
System: The UNT Digital Library
28-nm laser damage testing of LIF (open access)

28-nm laser damage testing of LIF

We have tested several samples of LIF, both single crystal and press forged, for damage resistance to 10-ns 248-nm pulses at 35 pps. The damage thresholds - the highest levels at which no damage could be produced - ranged from 4 to 6 J/cm/sup 2/ although some test sites survived irradiation at approx. 30 J/cm/sup 2/. We observed that bulk damage is the primary failure mechanism in single crystal and press forged samples and that both types exhibit the same resistance to laser damage.
Date: January 1, 1981
Creator: Foltyn, S. R. & Newman, B. E.
Object Type: Article
System: The UNT Digital Library
30-kV Proton Injector for PIGMI (open access)

30-kV Proton Injector for PIGMI

A 30-kV proton injector designed for matching a 31-mA proton beam into the radio-frequency quadrupole (RFQ) section of the PIGMI accelerator has been constructed and tested. This injector uses a small efficient duoplasmatron ion source and a single-gap extraction system for creating a convergent ion beam, and a three-element unipotential einzel lens for focusing the ion beam into the RFQ. A description of this prototype injector is presented, along with the experimental data obtained during the testing of this system.
Date: January 1, 1981
Creator: Hamm, R. W.; Mueller, D. W. & Sturgess, R. G.
Object Type: Article
System: The UNT Digital Library
30-MJ superconducting magnetic energy storage for BPA transmission-line stabilizer (open access)

30-MJ superconducting magnetic energy storage for BPA transmission-line stabilizer

The Bonneville Power Administration operates the transmission system that joins the Pacific Northwest and southern California. A 30 MJ (8.4 kWh) superconducting Magnetic Energy Storage (SMES) unit with a 10 MW converter can provide system damping for low frequency oscillations. The unit is scheduled to operate in late 1982. Progress to date is described. The coil is complete. All major components of the electrical and cryogenic systems have been received and testing has begun. Computer control hardware is in place and software development is proceeding. Support system components and dewar lid are being fabricated and foundation design is complete. A contract for dewar fabrication is being negotiated.
Date: January 1, 1981
Creator: Schermer, R.I.
Object Type: Article
System: The UNT Digital Library
30-MJ superconducting magnetic-energy storage for BPA transmission-line stabilizer (open access)

30-MJ superconducting magnetic-energy storage for BPA transmission-line stabilizer

The Bonneville Power Administration operates the transmission system that joins the Pacific Northwest and southern California. A 30 MJ (8.4 kWh) Superconducting Magnetic Energy Storage (SMES) unit with a 10 MW converter can provide system damping for low frequency oscillations. The unit is scheduled to operate in 1982. Progress during FY 81 is described. The coil is complete. All major components of the electrical and cryogenic systems have been received and testing has begun. Computer control hardware is in place and software development is proceeding. Support system components and dewar lid are being fabricated and foundation design is complete. A contract for dewar fabrication is being negotiated.
Date: January 1, 1981
Creator: Schermer, R. I.
Object Type: Article
System: The UNT Digital Library
30-MJ superconducting magnetic energy storage for electric-transmission stabilization (open access)

30-MJ superconducting magnetic energy storage for electric-transmission stabilization

The Bonneville Power Administration operates the electric power transmission system that connects the Pacific Northwest and southern California. The HVAC interties develop 0.35 Hz oscillations when the lines are heavily loaded. A 30 MJ (8.4 kWh) Superconducting Magnetic Energy Storage (SMES) unit with a 10 MW converter can provide system damping for the oscillation. The unit is scheduled for installation in 1982 and operation in 1982-83. Status of the project is described. The conductor has been fully tested electrically and mechanically and the 5 kA superconducting cable has been produced. The 30 MJ superconducting coil is essentially complete. All major components of the electrical and cryogenic systems except the nonconducting dewar have been completed. The refrigerator and converter are undergoing tests. The system is to be located at the BPA Tacoma Substation and operated by microwave link from Portland, OR.
Date: January 1, 1981
Creator: Turner, R. D. & Rogers, J. D.
Object Type: Article
System: The UNT Digital Library
100-kV, 2-ns risetime, dc-coupled probe (open access)

100-kV, 2-ns risetime, dc-coupled probe

A high-voltage probe has been designed and constructed; it is unique because it may be used for both high-voltage dc and for transient measurements. The probe is rated at 100-kV dc with a short transient rating of 150-kV peak. System risetime is less than 2 ns. The input impedance is 1000 M..cap omega.. shunted by 13 pF. A distributed RC network providing the desired attenuation is housed in a 25.4-cm-dia cylindrical housing. A 15.2-m length of coaxial cable connects the probe to a termination network at the oscilloscope input. The oscilloscope input impedance must be at least 100 k..cap omega.. to maintain the correct dc attenuation ratio.
Date: January 1, 1981
Creator: Power, J.; Nunnally, W. & Young, D.
Object Type: Article
System: The UNT Digital Library
200 Steamflood Demonstration Project. Fourth annual report, June 1979-June 1980 (open access)

200 Steamflood Demonstration Project. Fourth annual report, June 1979-June 1980

The 200 Sand Steamflood Demonstration Project is testing an enhanced steamflooding technique in the Midway-Sunset Field, Kern County, California. This project was initiated to demonstrate the operational, recovery, and economic aspects of steamflooding a typical heavy oil reservoir which had unfavorable response to cyclic steam stimulation. A pilot test was conducted in four (4) 2.35 acre inverted seven-spot steam drive patterns, which were not fully developed with producers. As a result of the response shown by the pilot, in April 1980, work began to expand the pilot area to a total of fourteen (14) fully developed 2.35 acre inverted seven-spot patterns. Expansion to a full-scale steamflood test will consist of drilling and completing 30 producing wells and 10 steam injection wells. The reservoir contains approximately 50 million barrels of oil-in-place in a structure that lies between 400 and 700 feet in depth.
Date: February 1, 1981
Creator: Alford, W O
Object Type: Report
System: The UNT Digital Library
300-MHz optical discriminator-counter (open access)

300-MHz optical discriminator-counter

The prediction of future CO/sub 2/ content in the atmosphere is not completely credible because the oceanographers and terrestrial ecologists do not agree on the global CO/sub 2/ balance. Very precise measurements of O/sub 2//N/sub 2/ ratio using Raman scattering over a few years' period could provide important information and lead to the explanation of the disparity in the atmospheric CO/sub 2/ balance. An optical discriminator-counter has been developed to count closely spaced optical events in the few photon level. Simulated optical events as close as 2.5 ns apart had been positively detected by using selected photomultipliers and optimized discriminators. Testing of the optical discriminator-counter was done by using an electrical pulse pair spaced 3 ns apart and also by a similar optical pulse pair generated by fast light-emitting diode. The photomultiplier is capable of counting an average single photoelectron pulse frequency of 50 MHz and has a sensitive detecting area of 50 mm in diameter. The discriminator performance is discussed.
Date: July 1, 1981
Creator: Turko, B. & Lo, C.C.
Object Type: Article
System: The UNT Digital Library
360/sup 0/ digital phase detector with 100-kHz bandwidth (open access)

360/sup 0/ digital phase detector with 100-kHz bandwidth

The general availability of digital circuit components with propagation delay times of a few nanoseconds makes a digital phase detector with good bandwidth feasible. Such a circuit has a distinct advantage over its analog counterpart because of its linearity over wide range of phase shift. A phase detector that is being built at Los Alamos National Laboratory for the Fusion Materials Irradiation Test (FMIT) project is described. The specifications are 100-kHz bandwidth, linearity of +- 1/sup 0/ over +- 180/sup 0/ of phase shift, and 0.66/sup 0/ resolution. To date, the circuit has achieved the bandwidth and resolution. The linearity is approximately +- 3/sup 0/ over +- 180/sup 0/ phase shift.
Date: January 1, 1981
Creator: Reid, D.W.; Riggin, D.; Fazio, M.V.; Biddle, R.S.; Patton, R.D. & Jackson, H.A.
Object Type: Article
System: The UNT Digital Library
500-kW DCHX pilot-plant evaluation testing (open access)

500-kW DCHX pilot-plant evaluation testing

Field tests with the 500 kW Direct Contact Pilot Plant were conducted utilizing brine from well Mesa 6-2. The tests were intended to develop comprehensive performance data, design criteria, and economic factors for the direct contact power plant. The tests were conducted in two phases. The first test phase was to determine specific component performance of the DCHX, turbine, condensers and pumps, and to evaluate chemical mass balances of non-condensible gases in the IC/sub 4/ loop and IC/sub 4/ in the brine stream. The second test phase was to provide a longer term run at nearly fixed operating conditions in order to evaluate plant performance and identify operating cost data for the pilot plant. During these tests the total accumulated run time on major system components exceeded 1180 hours with 777 hours on the turbine prime mover. Direct contact heat exchanger performance exceeded the design prediction.
Date: October 1, 1981
Creator: Hlinak, A.; Lee, T.; Loback, J.; Nichols, K.; Olander, R.; Oshmyansky, S. et al.
Object Type: Report
System: The UNT Digital Library
870. 8-keV gamma ray from PuO₂ (open access)

870. 8-keV gamma ray from PuO₂

A /sup 252/Cf neutron source and an /sup 241/Am alpha source were used with isotopically enriched water containing 43.9% /sup 17/O and 43.1% /sup 18/O, to study the (n,n'UPSILON) and (..cap alpha..,..cap alpha..'UPSILON) reactions in /sup 17/O and /sup 18/O. The production yields for the 870.8-keV gamma ray from /sup 17/O and the 1982.2-keV gamma ray from /sup 18/O were measured. In addition, the average cross sections over the /sup 252/Cf fission neutron spectrum for /sup 17/O(n,n'UPSILON)/sup 17/O and /sup 18/O(n,n'UPSILON)/sup 18/O were determined.
Date: January 1, 1981
Creator: Hsu, H.H.
Object Type: Article
System: The UNT Digital Library
1170-MW(t) HTGR-PS/C plant application study report: Geismar, Louisiana refinery/chemical complex application (open access)

1170-MW(t) HTGR-PS/C plant application study report: Geismar, Louisiana refinery/chemical complex application

This report summarizes a study to apply an 1170-MW(t) high-temperature gas-cooled reactor - process steam/cogeneration (HTGR-PS/C) to an industrial complex at Geismar, Louisiana. This study compares the HTGR with coal and oil as process plant fuels. This study uses a previous broad energy alternative study by the Stone and Webster Corporation on refinery and chemical plant needs in the Gulf States Utilities service area. The HTGR-PS/C was developed by General Atomic (GA) specifically for industries which require both steam and electric energy. The GA 1170-MW(t) HTGR-PC/C design is particularly well suited to industrial applications and is expected to have excellent cost benefits over other energy sources.
Date: May 1, 1981
Creator: McMain, Jr., A. T. & Stanley, J. D.
Object Type: Report
System: The UNT Digital Library
1170-MW(t) HTGR-PS/C plant application study report: shale oil recovery application (open access)

1170-MW(t) HTGR-PS/C plant application study report: shale oil recovery application

The US has large shale oil energy resources, and many companies have undertaken considerable effort to develop economical means to extract this oil within environmental constraints. The recoverable shale oil reserves in the US amount to 160 x 10/sup 9/ m/sup 3/ (1000 x 10/sup 9/ bbl) and are second in quantity only to coal. This report summarizes a study to apply an 1170-MW(t) high-temperature gas-cooled reactor - process steam/cogeneration (HTGR-PS/C) to a shale oil recovery process. Since the highest potential shale oil reserves lie in th Piceance Basin of Western Colorado, the study centers on exploiting shale oil in this region.
Date: May 1, 1981
Creator: Rao, R. & McMain, A.T. Jr.
Object Type: Report
System: The UNT Digital Library
1170-MW(t) HTGR-PS/C plant application study report: SRC-II process application (open access)

1170-MW(t) HTGR-PS/C plant application study report: SRC-II process application

The solvent refined coal (SRC-II) process is an advanced process being developed by Gulf Mineral Resources Ltd. (a Gulf Oil Corporation subsidiary) to produce a clean, non-polluting liquid fuel from high-sulfur bituminous coals. The SRC-II commercial plant will process about 24,300 tonnes (26,800 tons) of feed coal per stream day, producing primarily fuel oil plus secondary fuel gases. This summary report describes the integration of a high-temperature gas-cooled reactor operating in a process steam/cogeneration mode (HTGR-PS/C) to provide the energy requirements for the SRC-II process. The HTGR-PS/C plant was developed by General Atomic Company (GA) specifically for industries which require energy in the form of both steam and electricity. General Atomic has developed an 1170-MW(t) HTGR-PS/C design which is particularly well suited to industrial applications and is expected to have excellent cost benefits over other sources of energy.
Date: May 1, 1981
Creator: Rao, R. & McMain, A. T., Jr.
Object Type: Report
System: The UNT Digital Library
1170-MW(t) HTGR-PS/C plant application study report: tar sands oil recovery application (open access)

1170-MW(t) HTGR-PS/C plant application study report: tar sands oil recovery application

This report summarizes a study to apply an 1170-MW(t) high-temperature gas-cooled reactor - process steam/cogeneration (HTGR-PS/C) to tar sands oil recovery and upgrading. The raw product recovered from the sands is a heavy, sour bitumen; upgrading, which involves coking and hydrodesulfurization, produces a synthetic crude (refinable by current technology) and petroleum coke. Steam and electric power are required for the recovery and upgrading process. Proposed and commercial plants would purchase electric power from local utilities and obtain from boilers fired with coal and with by-product fuels produced by the upgrading. This study shows that an HTGR-PS/C represents a more economical source of steam and electric power.
Date: May 1, 1981
Creator: Rao, R. & McMain, Jr., A. T.
Object Type: Report
System: The UNT Digital Library