Resource Type

Colorado State University Solar Heated and Cooled House (open access)

Colorado State University Solar Heated and Cooled House

None
Date: January 1, 1974
Creator: Lof, G.O.G.
System: The UNT Digital Library
Elements of high constructive deltaic sedimentation, lower Frio Formation, Brazoria County, Texas (open access)

Elements of high constructive deltaic sedimentation, lower Frio Formation, Brazoria County, Texas

The lower Frio Formation in eastern Brazoria County, upper Texas Gulf Coast, was deposited in a high constructive deltaic environment in the Houston delta system. Constructive elements of the stacked, elongate to lobate deltas that were intersected in core are storm induced delta front splays, delta front slump deposits, and distributary mouth bar, distributary channel and delta plain assemblages. Reworked and winnowed abandonment facies that are volumetrically insignificant relative to constructive elements are subdivided into a crossbedded shoreface-foreshore subfacies and a fine grained cyclic sequence of storm deposits on the lower shoreface that represent a distal abandonment subfacies. Micropaleontological evidence indicates that deposition of constructive and abandonment facies took place in water depths of less than 120 feet.
Date: January 1, 1982
Creator: Tyler, N. & Han, J. H.
System: The UNT Digital Library
Tritium technology programs in the United States (open access)

Tritium technology programs in the United States

Tritium technology in the United States has advanced considerably since the 1988 Tritium Conferences in Toronto. This advance has come in facilities, processing and safety related technologies and in an ever increasing commitment to compliance related issues. The major laboratories in the US tritium programs continue to be (Westinghouse) Savannah River Site, EG G Mound, Lawrence Livermore National Laboratory, Sandia National Laboratory and the Los Alamos National Laboratory. Each of these Laboratories have made some significant changes in their programs and/or facilities in the past four years. 11 refs, 1 fig.
Date: January 1, 1991
Creator: Anderson, J. L.
System: The UNT Digital Library
New Hot Laboratory Facilities at Los Alamos (open access)

New Hot Laboratory Facilities at Los Alamos

New Hot Laboratory Facilities which support three major research programs directed by the Los Alamos Scientific Laboratory of the University of California are described. For the Nuclear Rocket Propulsion Program, a hot cell addition to the Radio Chemistry Building at Los Alamos will be completed early in 1963, and construction is expected to start soon on the hot cell addition to the Maintenance, Assembly and Disassembly Building at the Nuclear Rocket Development Station in Nevada. Integral hot laboratories are designed in the facilities for the Ultra High Temperature Reactor Experiment and the Fast Reactor Core Test at Los Alamos. (auth)
Date: January 1, 1962
Creator: Wherritt, Charles R.; Franke, Paul R.; Field, R. E. & Lyle, A. R.
System: The UNT Digital Library
Deep crustal sediment study: Widespread Precambrian layered rocks (Sedimentary) beneath the US midcontinent (open access)

Deep crustal sediment study: Widespread Precambrian layered rocks (Sedimentary) beneath the US midcontinent

A thick sequence of layered rocks occurs beneath the Phanerozoic platform strata which blanket the US midcontinent. Observed on COCORP deep reflection data in southern Illinois and Indiana and in SW Oklahoma and adjacent Texas, this sequence is locally 1--3 times as thick as the overlying Paleozoic cover, but the origin of this sequence, its ultimate lateral extent, and resource potential are unknown. The objective of this project is to seek and reprocess seismic reflection data provided by industry from the US midcontinent and together with the COCORP deep reflection data and information from the scattered basement-penetrating drill holes, to begin to constrain the distribution, origin and evolution of this enigmatic layered sequence, particularly to evaluate if sedimentary material may be an important constituent (i.e., deep gas potential).
Date: January 1, 1992
Creator: Hauser, E. C.
System: The UNT Digital Library
Steady-State Thermomechanical Finite Element Analysis of Elastoviscoplastic Metal Forming Processes (open access)

Steady-State Thermomechanical Finite Element Analysis of Elastoviscoplastic Metal Forming Processes

Extrusion and rolling processes exhibiting large amounts of plastic flow are analyzed using a finite element technique that is based on a modified creeping viscous flow approximation. The technique, called the initial stress-rate method, iteratively corrects creeping viscous flow solutions to generate results that include elastic response. The momentum equations have been coupled with the energy equation to provide the capability to predict thermomechanical response during forming operations.
Date: January 1, 1977
Creator: Dawson, P.R. & Thompson, E.G.
System: The UNT Digital Library
Clay mineralogy and depositional history of the Frio Formation in two geopressured wells, Brazoria County, Texas (open access)

Clay mineralogy and depositional history of the Frio Formation in two geopressured wells, Brazoria County, Texas

Twenty-three shale samples ranging in depth from 5194 ft to 13,246 ft from Gulf Oil Corporation No. 2 Texas State Lease 53034 well and 33 shale samples ranging in depth from 2185 ft to 15,592 ft from General Crude Oil Company/Department of Energy No. 1 Pleasant Bayou well were examined by x-ray techniques to determine the mineralogy of the geopressured zone in the Brazoria Fairway. Both wells have similar weight-percent trends with depth for a portion of the mineralogy. Calcite decreases, and plagioclase, quartz and total clay increase slightly. Within the clays, illite in mixed-layer illite/smectite (I/S) increases and smectite in mixed-layer I/S decreases. Four minerals have distinctly different trends with depth for each well. In the No. 2 Texas State Lease 53034 well, potassium feldspar and mixed-layer I/S decrease, kaolinite increases, and discrete illite is constant. In the No. 1 Pleasant Bayou well, potassium feldspar and kaolinite are constant, mixed-layer I/S increases, and discrete illite decreases.
Date: January 1, 1982
Creator: Freed, R.L.
System: The UNT Digital Library
Dual arm master controller development (open access)

Dual arm master controller development

The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. This work was performed as part of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 5 refs., 7 figs., 1 tab.
Date: January 1, 1985
Creator: Kuban, D. P. & Perkins, G. S.
System: The UNT Digital Library
Influence of Geometry on Natural Convection in Buildings (open access)

Influence of Geometry on Natural Convection in Buildings

Strong free convection airflows occur within passive solar buildings resulting from elevated temperatures of surfaces irradiated by solar energy compared with the cooler surfaces not receiving radiation. The geometry of a building has a large influence on the directions and magnitudes of natural airflows, and thus heat transfer between zones. This investigation has utilized a variety of reduced-scale building configurations to study the effects of geometry on natural convection heat transfer. Similarity between the reduced-scale model and a full-scale passive solar building is achieved by having similar geometries and by replacing air with Freon-12 gas as the model's working fluid. Filling the model with Freon-12 gas results in similarity in Prandtl numbers and Rayleigh numbers based on temperature differences in the range from 10/sup 9/ to 10/sup 11/. Results from four geometries are described with an emphasis placed on the effects of heat loss on zone temperature stratification shifts.
Date: January 1, 1985
Creator: White, M. D.; Winn, C. B.; Jones, G. F. & Balcomb, J. D.
System: The UNT Digital Library
Review of nuclear reaction data evaluation in the US (open access)

Review of nuclear reaction data evaluation in the US

The development of the nuclear reaction data evaluation activities in the US over the last 40 years is reviewed, starting with comments on several reports as early as 1944. The review moves on to the development of consortia to share the burden by interchanging sets of data and efforts toward putting together an encoding system and computer-oriented formats. It is predicted that future emphasis is likely to be on charged particle induced reactions. (LEW)
Date: May 1, 1985
Creator: Howerton, Robert J.
System: The UNT Digital Library
Low Energy X-Ray Spectra Measured With a Mercuric Iodide Energy Dispersive Spectrometer in a Scanning Electron Microscope (open access)

Low Energy X-Ray Spectra Measured With a Mercuric Iodide Energy Dispersive Spectrometer in a Scanning Electron Microscope

A mercuric iodide energy dispersive x-ray spectrometer, with Peltier cooling provided for the detector and input field effect transistor, has been developed and tested in a scanning electron microscope. X-ray spectra were obtained with the 15 keV electron beam. An energy resolution of 225 eV (FWHM) for Mn-K/sub ..cap alpha../ at 5.9 keV and 195 eV (FWHM) for Mg-K line at 1.25 keV has been measured. Overall system noise level was 175 eV (FWHM). The detector system characterization with a carbon target demonstrated good energy sensitivity at low energies and lack of significant spectral artifacts at higher energies. 16 refs., 5 figs.
Date: January 1, 1985
Creator: Iwanczyk, J. S.; Dabrowski, A. J.; Huth, G. C.; Bradley, J. G.; Conley, J. M. & Albee, A. L.
System: The UNT Digital Library
Refractory materials for high-temperature thermoelectric energy conversion (open access)

Refractory materials for high-temperature thermoelectric energy conversion

Theoretical work of two decades ago adequately explained the transport behavior and effectively guided the development of thermoelectric materials of high conversion efficiencies of conventional semiconductors (e.g., SiGe alloys). The more significant contributions involved the estimation of optimum doping concentrations, the reduction of thermal conductivity by solid solution doping and the development of a variety of materials with ZT approx. 1 in the temperature range 300 K to 1200 K. It was also shown that ZT approx. 1 is not a theoretical limitation although, experimentally, values in excess of one were not achieved. Work has continued with emphasis on higher temperature energy conversion. A number of promising materials have been discovered in which it appears that ZT > 1 is realizable. These materials can be divided into two classes: (i) the rare-earth chalcogenides, which behave as itinerant highly-degenerate n-type semiconductors at room-temperature, and (ii) the boron-rich borides, which exhibit p-type small-polaronic hopping conductivity.
Date: January 1, 1983
Creator: Wood, C. & Emin, D.
System: The UNT Digital Library
Borehole Seismic Monitoring of Injected CO2 at the Frio Site (open access)

Borehole Seismic Monitoring of Injected CO2 at the Frio Site

As part of a small scale sequestration test (about 1500 tonsof CO2) in a saline aquifer, time-lapse borehole seismic surveys wereconducted to aid in characterization of subsurface CO2 distribution andmaterial property changes induced by the injected CO2. A VSP surveydemonstrated a large increase (about 75 percent) in seismic reflectivitydue to CO2 injection and allowed estimation of the spatial extent of CO2induced changes. A crosswell survey imaged a large seismic velocitydecrease (up to 500 m/s) within the injection interval and provided ahigh resolution image of this velocity change which maps the subsurfacedistribution of CO2 between two wells. Numerical modeling of the seismicresponse uses the crosswell measurements to show that this small CO2volume causes a large response in the seismic reflectivity. This resultdemonstrates that seismic detection of small CO2 volumes in salineaquifers is feasible and realistic.
Date: April 21, 2006
Creator: Daley, Thomas M.; Myer, Larry R.; Hoversten, G.M.; Peterson, JohnE. & Korneev, Valeri A.
System: The UNT Digital Library
Rapid estimation of /sup 226/Ra in soil for the Grand Junction RASA/UMTRA project (open access)

Rapid estimation of /sup 226/Ra in soil for the Grand Junction RASA/UMTRA project

The Radiological Survey Activities (RASA) Group of the Health and Safety Research Division at Oak Ridge National Laboratory (ORNL) is an Inclusion Survey Contractor (ISC) for the Uranium Mill Tailings Remedial Action Program (UMTRAP). The purpose of the ISC is to survey designated sites potentially contaminated with radioactive material originating from the 24 inactive uranium mill sites and make recommendations as to whether the site should be included in or excluded from further consideration by UMTRAP. An important aspect of the program is a prompt and inexpensive estimation of Radium-226 (/sup 226/Ra) concentration in soil samples. A large sodium iodide (NaI) well crystal coupled to a multichannel analyzer is used to count soil samples. Count data are currently analyzed with an algorithm that utilizes three regions of interest (ROI). A lack of agreement was observed when samples were also analyzed with lithium-drifted germanium (GeLi) spectrometers. The average estimate of /sup 226/Ra obtained using the current algorithm was 19% greater than the GeLi determination. Some possible reasons for these differences were examined. In 8.5% of the samples, the relative concentration of Cesium-137 (/sup 137/Cs) was highly correlated to the extent of error. Using alternative analysis techniques, the error for /sup 226/Ra …
Date: January 1, 1986
Creator: Kark, J.B.; Borak, T.B.; Kearney, P.D. & Rood, A.S.
System: The UNT Digital Library
Interplanetary propulsion using inertial fusion (open access)

Interplanetary propulsion using inertial fusion

Inertial fusion can be used to power spacecraft within the solar system and beyond. Such spacecraft have the potential for short-duration manned-mission performance exceeding other technologies. We are conducting a study to assess the systems aspects of inertial fusion as applied to such missions, based on the conceptual engine design of Hyde (1983) we describe the required systems for an entirely new spacecraft design called VISTA that is based on the use of DT fuel. We give preliminary design details for the power conversion and power conditioning systems for manned missions to Mars of total duration of about 100 days. Specific mission performance results will be published elsewhere, after the study has been completed.
Date: January 1, 1987
Creator: Orth, C.D.; Hogan, W.J.; Hoffman, N.; Murray, K.; Klein, G. & Diaz, F.C.
System: The UNT Digital Library
The VISTA spacecraft: Advantages of ICF (Inertial Confinement Fusion) for interplanetary fusion propulsion applications (open access)

The VISTA spacecraft: Advantages of ICF (Inertial Confinement Fusion) for interplanetary fusion propulsion applications

Inertial Confinement Fusion (ICF) is an attractive engine power source for interplanetary manned spacecraft, especially for near-term missions requiring minimum flight duration, because ICF has inherent high power-to-mass ratios and high specific impulses. We have developed a new vehicle concept called VISTA that uses ICF and is capable of round-trip manned missions to Mars in 100 days using A.D. 2020 technology. We describe VISTA's engine operation, discuss associated plasma issues, and describe the advantages of DT fuel for near-term applications. Although ICF is potentially superior to non-fusion technologies for near-term interplanetary transport, the performance capabilities of VISTA cannot be meaningfully compared with those of magnetic-fusion systems because of the lack of a comparable study of the magnetic-fusion systems. We urge that such a study be conducted.
Date: October 2, 1987
Creator: Orth, C.D.; Klein, G.; Sercel, J.; Hoffman, N.; Murray, K. & Chang-Diaz, F.
System: The UNT Digital Library
Comparative Performance of Two Types of Evacuated Tube Solar Collectors in a Residential Heating and Cooling System - The Progress Report (open access)

Comparative Performance of Two Types of Evacuated Tube Solar Collectors in a Residential Heating and Cooling System - The Progress Report

Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in the Corning design, whereas heat is conducted through a single glass wall to an external heat exchanger plate in the Philips collector. In comparison with conventional flat-plate collectors, both types show reduced heat losses and improved efficiency. For space heating and hot water supply in winter, the solar delivery efficiency of the Corning collector ranged from 49% to 60% of the incident solar energy. The portion of the space heating and domestic hot water load carried by solar energy through fall and winter ranged from 50% to 74%, with a four-month contribution of 61% of the total requirements. Data on the Philips collector are currently being analyzed.
Date: January 1, 1979
Creator: Conway, T. M.; Duff, W. S.; Loef, G. O. G. & Pratt, R. G.
System: The UNT Digital Library
What Has Happened to the Survivors of the Early Los Alamos Nuclear Accidents? (open access)

What Has Happened to the Survivors of the Early Los Alamos Nuclear Accidents?

Abstract: Two nuclear accidents involving a plutonium sphere just subcritical in size occurred at the Los Alamos Laboratory, LA-1 in 1945 and LA-2 in 1946. Because remote control devices were deemed unreliable at the time, the tamper material (tungsten carbide bricks in LA-1 and beryllium hemispheres in LA-2) was added by hand with the operator standing next to the assembly. In each case the critical size of the assembly was accidentally exceeded and the resultant exponentially increasing chain reaction emitted a burst of neutrons and gamma rays. Ten persons were exposed to the radiation bursts which were largely composed of neutrons. The doses ranged from fatal in the case of the two operators, to small in the case of some survivors. The two operators died within weeks as a result of acute radiation injury. Only six of the eight survivors were available for follow-up study ten or more years after the accident. Four of these six survivors are now dead, but the two living survivors are in excellent health with no clinical or laboratory evidence of late radiation injury. Two of the deceased died of acute myelogenous leukemia, another died at age 83 of refractory anemia, and the fourth of …
Date: 1979
Creator: Hempelman, Louis Henry; Lushbaugh, Clarence C. & Voelz, George L.
System: The UNT Digital Library
Semiconductor processing with excimer lasers (open access)

Semiconductor processing with excimer lasers

The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Extensive comparisons of the quality of annealing of ion-implanted Si obtained with XeCl and ruby lasers have been made. The results indicate that irrespective of the large differences in the optical properties of Si at uv and visible wavelengths, the efficiency of usage of the incident energy for annealing is comparable for the two lasers. However, because of the excellent optical beam quality, the XeCl laser can provide superior control of the surface melting and the resulting junction depth. Furthermore, the concentrations of electrically active point defects in the XeCl laser annealed region are 2 to 3 orders of magnitude lower than that obtained from ruby or Nd:YAG lasers. All these results seem to suggest that XeCl lasers should be suitable for fabricating not only solar cells but also the more advanced device structures required for VLSI or VHSIC applications.
Date: January 1, 1983
Creator: Young, R.T.; Narayan, J.; Christie, W.H.; van der Leeden, G.A.; Rothe, D.E. & Cheng, L.J.
System: The UNT Digital Library
Neutral sheet crossings in the distant magnetotail (open access)

Neutral sheet crossings in the distant magnetotail

We have analyzed the magnetic field data from ISEE-3 in the distant magnetotail for 18 crossings of the cross-tail current sheet (or so-called natural sheet) to determine the direction of the normal component B/sub z/. The crossings occurred near the middle of the aberrated magnetotail (0 < y < 30 R/sub e, -10 < z < 5) in GSM coordinates, at a distance of about 220 R/sub e/, January 28 to February 12, 1983; in each case the plasma flow velocity was tailward. In 2 cases we found B/sub z/ negative (southward), as would be required with a magnetic neutral line (reconnection line) earthward of the spacecraft. In 12 cases B/sub z/ was clearly northward (B/sub z/ > 0.4 nT), consistent with closed field lines connected to the earth. In 3 cases B/sub z/ was very close to zero; in several instances there was structure in B/sub y/, suggesting localized currents with x or z directions. One may have been a magnetopause crossing. The strong preponderance of northward B/sub z/ favors a model of the magnetotail which is dominated by boundary layer plasma, flowing tailward on closed magnetic field lines, which requires the existence of an electric field in the …
Date: January 1, 1985
Creator: Heikkila, W. J.; Slavin, J. A.; Smith, E. J.; Baker, D. N. & Zwickl, R. D.
System: The UNT Digital Library
Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter) (open access)

Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of the alkali metal, and low electrical resistance, other high temperature components of the cell face equally demanding requirements. The beta{double prime} alumina solid electrolyte (BASE), the seal between the BASE ceramic and its metallic transition to the hot alkali metal (liquid or vapor) source, and metallic components of the device are exposed to hot liquid alkali metal. Modification of AMTEC components may also be useful in optimizing the device for particular operating conditions. In particular, a potassium AMTEC may be expected to operate more efficiently at lower temperatures.
Date: January 1, 1991
Creator: Williams, R.M.; Jeffries-Nakamura, B.; Underwood, M.L.; Ryan, M.A.; O'Connor, D. & Kikkert, S.
System: The UNT Digital Library
Transport vehicle for manned Mars missions powered by inertial confinement fusion (open access)

Transport vehicle for manned Mars missions powered by inertial confinement fusion

Inertial confinement fusion (ICF) is an ideal engine power source for manned spacecraft to Mars because of its inherently high power-to-mass ratios and high specific impulses. We have produced a concept for a vehicle powered by ICF and utilizing a magnetic thrust chamber to avoid plasma thermalization with wall structures and the resultant degradation of specific impulse that are unavoidable with the use of mechanical thrust chambers. This vehicle is capable of 100-day manned Mars missions with a 100-metric-ton payload and a total vehicle launch mass near 6000 metric tons, based on advanced technology assumed to be available by A.D. 2020. Such short-duration missions minimize radiation exposures and physiological deterioration of astronauts.
Date: June 26, 1987
Creator: Orth, C.D.; Klein, G.; Sercel, J.; Hoffman, N.; Murray, K. & Chang-Diaz, F.
System: The UNT Digital Library
Comparison of the Response of a Nai Scintillation Crystal With a Pressurized Ionization Chamber as a Function of Altitude, Radiation Level and RA-226 Concentration (open access)

Comparison of the Response of a Nai Scintillation Crystal With a Pressurized Ionization Chamber as a Function of Altitude, Radiation Level and RA-226 Concentration

The Grand Junction Uranium Mill Tailings Remedial Action-Radiological Survey Activities Group (UMTRA-RASA) program employs a screening method in which external exposure rates are used to determine if a property contaminated with uranium mill tailings is eligible for remedial action. Portable NaI detectors are used by survey technicians to locate contaminated areas and determine exposure rates. The exposure rate is calculated using a regression equation derived from paired measurements made with a pressurized ionization chamber (PIC) and a NaI detector. During July of 1985 extensive measurements were taken using a PIC and a NaI scintillator with both analogue and digital readout for a wide range of exposure rates and at a variety of elevations. The surface soil was sampled at most of these locations and analyzed for /sup 226/Ra. The response of the NaI detectors was shown to be highly correlated to radiation level but not to /sup 226/Ra concentration or elevation.
Date: January 1, 1986
Creator: Provencher, R.; Smith, G.; Borak, T.B. & Kearney, P.
System: The UNT Digital Library