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Predicting the Future at Yucca Mountain (open access)

Predicting the Future at Yucca Mountain

This paper summarizes a climate-prediction model funded by the DOE for the Yucca Mountain nuclear waste repository. Several articles in the open literature attest to the effects of the Global Ocean Conveyor upon paleoclimate, specifically entrance and exit from the ice age. The data shows that these millennial-scale effects are duplicated on the microscale of years to decades. This work also identifies how man may have influenced the Conveyor, affecting global cooling and warming for 2,000 years.
Date: July 1, 1999
Creator: Wilson, J. R.
Object Type: Article
System: The UNT Digital Library
Liquid abrasive grit blasting literature search and decontamination scoping tests report (open access)

Liquid abrasive grit blasting literature search and decontamination scoping tests report

Past decontamination and solvent recovery activities at the Idaho Chemical Processing Plant (ICPP) have resulted in the accumulation of 1.5 million gallons of radioactively contaminated sodium-bearing liquid waste. Future decontamination activities at the ICPP could result in the production of 5 million gallons or more of sodium-bearing waste using the current decontamination techniques of chemical/water flushes and steam jet cleaning. With the curtailment of reprocessing at the ICPP, the focus of decontamination is shifting from maintenance for continued operation of the facilities to decommissioning. As decommissioning plans are developed, new decontamination methods must be used which result in higher decontamination factors and generate lower amounts of sodium-bearing secondary waste. The primary initiative of the WINCO Decontamination Development Program is the development of methods to eliminate/minimize the use of sodium-bearing decontamination chemicals. One method that was chosen for cold scoping studies during FY-93 was abrasive grit blasting. Abrasive grit blasting has been used in many industries and a vast amount of research and development has already been conducted. However, new grits, process improvements and ICPP applicability was investigated. This evaluation report is a summary of the research efforts and scoping tests using the liquid abrasive grit blasting decontamination technique. The purpose …
Date: October 1, 1993
Creator: Ferguson, R.L.
Object Type: Report
System: The UNT Digital Library
Crystal field in the heavy fermion compound CeAl{sub 3}. (open access)

Crystal field in the heavy fermion compound CeAl{sub 3}.

Although the crystal field has a strong influence on the heavy fermion properties of CeAl{sub 3}, the parameters of the crystal field Hamiltonian have not been established. We present the results of an analysis of inelastic neutron scattering data on CeAl{sub 3} to resolve this issue. By combining the neutron scattering results with measurements of the single crystal magnetic susceptibility, we have obtained an unambiguous set of crystal field parameters in CeAl{sub 3}: B{sub 2}{sup 0} = (5.8 {+-} 0.2) x 10{sup {minus}2} meV and B{sub 4}{sup 0} = (2.3 {+-} 0.1) x 10{sup {minus}2} meV. The corresponding level scheme of the ground multiplet of the Ce{sup 3+} ion is characterized by a {Lambda}{sub 9} {vert_bar} {+-} 3/2> ground state doublet and two close-lying excited doublets {Lambda}{sub 8} {vert_bar} {+-} 5/2> and {Lambda}{sub 7} {vert_bar} {+-} 1/2> at an energy of {approximately} 6.4 meV at 20 K. A comparison of the crystal field parameters along the RAl{sub 3} (R = Ce, Pr and Nd) series of isostructural compounds shows that in CeAl{sub 3}, A{sub 2}{sup 0} <r{sup 2}> is an order of magnitude larger, and A{sub 4}{sup 0} <R{sup 4}> is three times larger, than in PrAl{sub 3} and NdAl{sub …
Date: September 11, 1998
Creator: Goremychkin, E. A.
Object Type: Article
System: The UNT Digital Library
Task 3.14 - Demonstration of Technologies for Remote Power Generation in Alaska (open access)

Task 3.14 - Demonstration of Technologies for Remote Power Generation in Alaska

In over 165 villages in Alaska, the use of fossil fuel supplies or renewable energy resources could greatly reduce the cost of electricity and space heating. Currently, diesel generators are the most commonly used electrical generating systems; however, high fuel costs result in extremely high electrical power costs reIative to the lower 48 states. The reduction of fuel costs associated with the use of indigenous, locally available fuels running modular, high-efficiency power- generating systems would be extremely beneficial.
Date: February 1, 1998
Creator: Jones, Michael L.
Object Type: Report
System: The UNT Digital Library
Yucca Mountain Project thermal and mechanical codes first benchmark exercise: Part 3, Jointed rock mass analysis; Yucca Mountain Site Characterization Project (open access)

Yucca Mountain Project thermal and mechanical codes first benchmark exercise: Part 3, Jointed rock mass analysis; Yucca Mountain Site Characterization Project

Thermal and mechanical models for intact and jointed rock mass behavior are being developed, verified, and validated at Sandia National Laboratories for the Yucca Mountain Site Characterization Project. Benchmarking is an essential part of this effort and is one of the tools used to demonstrate verification of engineering software used to solve thermomechanical problems. This report presents the results of the third (and final) phase of the first thermomechanical benchmark exercise. In the first phase of this exercise, nonlinear heat conduction code were used to solve the thermal portion of the benchmark problem. The results from the thermal analysis were then used as input to the second and third phases of the exercise, which consisted of solving the structural portion of the benchmark problem. In the second phase of the exercise, a linear elastic rock mass model was used. In the third phase of the exercise, two different nonlinear jointed rock mass models were used to solve the thermostructural problem. Both models, the Sandia compliant joint model and the RE/SPEC joint empirical model, explicitly incorporate the effect of the joints on the response of the continuum. Three different structural codes, JAC, SANCHO, and SPECTROM-31, were used with the above models …
Date: October 1, 1991
Creator: Costin, L. S. & Bauer, S. J.
Object Type: Report
System: The UNT Digital Library
Direct flow in 10.8 GeV/nucleon Au+Au collisions measured in experiment E917 at the AGS. (open access)

Direct flow in 10.8 GeV/nucleon Au+Au collisions measured in experiment E917 at the AGS.

Analysis of directed flow observable for protons and pions from Au+Au collisions at 10.8 GeV/nucleon from experiment E917 at the AGS is presented. Using a Fourier series expansion, the first Fourier component, {nu}{sub 1},was extracted as a function of rapidity for mid-central collisions (17-24%). Clear evidence for positive directed flow is found in the proton data, and a weak, possibly negative directed flow signal is observed for {pi}{sup +} and {pi}{sup {minus}}.
Date: May 19, 1999
Creator: Back, B. B.; Betts, R. R.; Britt, H. C.; Chang, J.; Chang, W. C.; Gillitzer, A. et al.
Object Type: Article
System: The UNT Digital Library
Volatilization of Fission Products from Metallic Melts in the Melt-Dilute Treatment Technology Development for Al-Based DOE Spent Nuclear Fuels (open access)

Volatilization of Fission Products from Metallic Melts in the Melt-Dilute Treatment Technology Development for Al-Based DOE Spent Nuclear Fuels

The melt-dilute treatment technology is being developed to facilitate the ultimate disposition of highly enriched Al-Base DOE spent nuclear fuels in a geologic repository such as that proposed for Yucca Mountain. Currently, approximately 28 MTHM is expected to be returned to the Savannah River Site from domestic and foreign research reactors. The melt-dilute treatment technology will melt the fuel assemblies to reduce their volume and alloys them with depleted uranium to isotopically dilute the 235U concentration. The resulting alloy is cast into a form for long term geologic repository storage. Benefits accrued from the melt-dilute process include the potential for significant volume reduction; reduced criticality potential, and proliferation concerns. A critical technology element in the development of the melt-dilute process is the development of offgas system requirements. The volatilization of radioactive species during the melting stage of the process primarily constitutes the offgas in this process. Several of the species present following irradiation of a fuel assembly have been shown to be volatile or semi-volatile under reactor core melt-down conditions. Some of the key species that have previously been studied are krypton, iodine, and cesium. All of these species have been shown to volatilize during melting experiments however, the degree …
Date: November 18, 1999
Creator: Adams, T.
Object Type: Article
System: The UNT Digital Library
A progress report on the g-2 storage ring magnet system (open access)

A progress report on the g-2 storage ring magnet system

The 3.1 GeV muon storage ring for the g-2 experiment at Brookhaven National Laboratory hat three large solenoid magnets that form a continuous 1.451 tesla storage ring dipole with an average beam bond radius of 7.1 metors. In addition to the three storage ring solenoids, there is an inflector dipole with nested dipole coils that create very little stray magnetic field. A superconducting shield on the infractor gets rid of most of the remaining stray flux. This paper reports on the progress made on the storage ring solenoid magnet system and the inflector as of June 1995. The results of cryogenic system tests are briefly reported.
Date: August 1995
Creator: Bunce, G.; Cullen, J. & Danby, G.
Object Type: Article
System: The UNT Digital Library
Analysis of releases due to drilling at the potential Yucca Mountain repository (open access)

Analysis of releases due to drilling at the potential Yucca Mountain repository

Human Instrusion into the potential repository at Yucca Mountain, Nevada, was modeled in the Total-System Performance Assessment (``TSPA-91``) recently completed for the Yucca Mountain Site Characterization Project Office of the DOE. The scenario model assumed that the repository would be penetrated at random locations by a number of boreholes drilled using twentieth-century rotary drilling techniques.
Date: July 1, 1993
Creator: Barnard, R.W.
Object Type: Article
System: The UNT Digital Library
A preliminary measurement of R{sub b} = {Gamma}({Zeta}{degrees} {yields} b{bar b})/{Gamma}({Zeta}{degrees} {yields} hadrons) at SLD (open access)

A preliminary measurement of R{sub b} = {Gamma}({Zeta}{degrees} {yields} b{bar b})/{Gamma}({Zeta}{degrees} {yields} hadrons) at SLD

We present a preliminary measurement of R{sub b}, the ratio of {Gamma}(Z{degree} - b{bar b}) relative to {Gamma}(Z{degree} {yields} hadrons) using the silicon CCD-pixel vertex detector of the SLD at the SLAC Linear Collider (SLC). An impact parameter method and a displaced vertex method are applied to all charged tracks, to efficiently tag Z{degree} - b{bar b} events. From the impact (displaced vertex) approach we find R{sub b} = 0.214 {plus_minus} 0.010 {plus_minus} 0.025 (R{sub b} = 0.204 {plus_minus} 0.010 {plus_minus} 0.030), consistent with the standard model value.
Date: November 1, 1992
Creator: Su, D. & Collaboration, The SLD
Object Type: Article
System: The UNT Digital Library
Research on oil recovery mechanisms in heavy oil reservoirs. [Quarterly] report, April--June 30, 1995 (open access)

Research on oil recovery mechanisms in heavy oil reservoirs. [Quarterly] report, April--June 30, 1995

The goal of the Stanford University Petroleum Research Institute is to conduct research directed toward increasing the recovery of heavy oils. Presently, SUPRI is working in five main directions: (1) Flow properties studies -- To assess the influence of different reservoir conditions (temperature and pressure) on the absolute and relative permeability to oil and water and on capillary pressure. (2) In-situ combustion -- To evaluate the effect of different reservoir parameters on the in-situ combustion process. Ibis project includes the study of the kinetics of the reactions. (3) Steam with additives - To develop and understand the mechanisms of the process using commercially available surfactants for reduction of gravity override and channeling of steam. (4) Formation evaluation -- To develop and improve techniques of formation evaluation such as tracer tests and pressure transient tests. (5) Field support services -- To provide technical support for design and monitoring of DOE sponsored or industry initiated field projects. Accomplishments for this quarter are briefly described for each study.
Date: September 1, 1995
Creator: Brigham, W.E.
Object Type: Report
System: The UNT Digital Library
Calendar year 1994 groundwater quality report for the Upper East Fork Poplar Creek Hydrogeologic Regime, Y-12 Plant, Oak Ridge, Tennessee (open access)

Calendar year 1994 groundwater quality report for the Upper East Fork Poplar Creek Hydrogeologic Regime, Y-12 Plant, Oak Ridge, Tennessee

This groundwater quality report (GWQR) contains an evaluation of the groundwater quality data obtained during the 1994 calendar year (CY) at several waste-management facilities and a petroleum fuel underground storage tank (UST) site at the US Department of Energy (DOE) Y-12 Plant located on the DOE Oak Ridge Reservation (ORR) southeast of Oak Ridge, Tennessee. These sites lie within the boundaries of the Upper East Fork Poplar Creek Hydrogeologic Regime (East Fork Regime), which is one of three hydrogeologic regimes defined for the purposes of groundwater quality monitoring at the Y-12 Plant. The Environmental Management Department of the Y-12 Plant Health, Safety, Environment, and Accountability (HSEA) Organization manages the groundwater monitoring activities in each regime under the auspices of the Y-12 Plant Groundwater Protection Program (GWPP). The purpose of the GWPP is to characterize the hydrogeology and to monitor groundwater quality at the Y-12 Plant and surrounding area to ensure protection of local groundwater resources in accordance with federal, state, and local regulations, DOE Orders, and Lockheed Martin Energy Systems, Inc. (Energy Systems) corporate policy.
Date: October 1, 1995
Creator: unknown
Object Type: Report
System: The UNT Digital Library
MELCOR ex-vessel LOCA simulations for ITER{sup +} (open access)

MELCOR ex-vessel LOCA simulations for ITER{sup +}

Ex-vessel Loss-of-Coolant-Accident (LOCA) simulations for the International Thermonuclear Experimental Reactor (ITER) were performed using the MELCOR code. The main goals of this work were to estimate the ultimate pressurization of the heat transport system (HTS) vault in order to gauge the potential for stack releases and to estimate the total amount of hydrogen generated during a design basis ex-vessel LOCA. Simulation results indicated that the amount of hydrogen produced in each transient was below the flammability limit for the plasma chamber. In addition, only moderate pressurization of the HTS vault indicated a very small potential for releases through the stack.
Date: November 1, 1995
Creator: Gaeta, M. J.; Merrill, B. J. & Bartels, H. W.
Object Type: Article
System: The UNT Digital Library
1998 Environmental Monitoring Program Report for the Idaho National Engineering and Environmental Laboratory (open access)

1998 Environmental Monitoring Program Report for the Idaho National Engineering and Environmental Laboratory

This report describes the calendar year 1998 compliance monitoring and environmental surveillance activities of the Lockheed Martin Idaho Technologies Company Environmental Monitoring Program performed at the Idaho National Engineering and Environmental Laboratory. This report includes results of sampling performed by the Drinking Water, Effluent, Storm Water, Groundwater Monitoring, and Environmental Surveillance Programs. This report compares the 1998 results to program-specific regulatory guidelines and past data to evaluate trends. The primary purposes of the monitoring and surveillance activities are to evaluate environmental conditions, to provide and interpret data, to verify compliance with applicable regulations or standards, and to ensure protection of public health and the environment. Surveillance of environmental media did not identify any previously unknown environmental problems or trends, which would indicate a loss of control or unplanned releases from facility operations. The INEEL complied with permits and applicable regulations, with the exception of nitrogen samples in a disposal pond effluent stream and iron and total coliform bacteria in groundwater downgradient from one disposal pond. Data collected by the Environmental Monitoring Program demonstrate that the public health and environment were protected.
Date: September 1, 1999
Creator: Street, L. V.
Object Type: Report
System: The UNT Digital Library
Degradation of a N06690 borescope in a radioactive waste/glass melter system (open access)

Degradation of a N06690 borescope in a radioactive waste/glass melter system

Radioactive liquid waste from nuclear materials production processes wi11 be vitrified in the Defense Waste Process Facility (DWPF) melter. The melter borescope outer housing, fabricated from N06690, was severely degraded by the combined effects of corrosion and oxidation after only five months of non radioactive operation. The melter was idled and not being fed over 85% of the time during the cold run operations. The borescope was designed to perform in an oxygen rich, chloride containing environment with temperatures approaching 900{degree}C (1650{degree}F). The housing was designed for a minimum of two years of continuous service in the DWPF melter. Air and steam were purged through the borescope and swept over the optics assembly to keep molten glass and volatile gases from depositing on the lens cover. Upon exiting the borescope the air passes through a N06690 orifice and enters the melter. Severe oxidation was observed around the orifice. Extensive material loss was also observed on the side of the outer housing which protrudes through the dome of the melter. Redesign of the borescope is currently underway and will include a new set of optics that will allow the size of the orifice to be significantly decreased, thus reducing the amount …
Date: September 1995
Creator: Imrich, K. J.
Object Type: Article
System: The UNT Digital Library
Accelerator Physics Challenges for Future Linear Colliders (open access)

Accelerator Physics Challenges for Future Linear Colliders

At the present time, there are a number of future linear collider designs with a center-of-mass energy of 500 GeV or more with luminosities in excess of 10{sup -34}cm{sup -2}s{sup -1} . Many of these designs are at an advanced state of development. However, to attain the high luminosity, the colliders require very small beam emittances, strong focusing, and very good stability. In this paper, some of the outstanding issues related to producing and maintaining the small beam sizes are discussed. Although the different designs are based on very different rf technologies, many of these problems are common.
Date: August 9, 1999
Creator: Raubenheimer, Tor O
Object Type: Report
System: The UNT Digital Library
Advanced Emissions Control Development Program (open access)

Advanced Emissions Control Development Program

The objective of the Advanced Emissions Control Development Program (AECDP) is to develop practical, cost-effective strategies for reducing the emissions of air toxics from coal-fired boilers. Ideally, the project aim is to effectively control air toxic emissions through the use of conventional flue gas cleanup equipment such as electrostatic precipitators (ESPS), fabric filters (baghouse), and wet flue gas desulfurization. Development work to date has concentrated on the capture of mercury, other trace metals, fine particulate and hydrogen chloride. Following the construction and evaluation of a representative air toxics test facility in Phase I, Phase II focused on the evaluation of mercury and several other air toxics emissions. The AECDP is jointly funded by the United States Department of Energy's Federal Energy Technology Center (DOE), the Ohio Coal Development Office within the Ohio Department of Development (oCDO), and Babcock& Wilcox-a McDermott company (B&W).
Date: April 1, 1998
Creator: A.P.Evans; Redinger, K.E. & Holmes, M.J.
Object Type: Report
System: The UNT Digital Library
Advanced Blade Manufacturing Project - Final Report (open access)

Advanced Blade Manufacturing Project - Final Report

The original scope of the project was to research improvements to the processes and materials used in the manufacture of wood-epoxy blades, conduct tests to qualify any new material or processes for use in blade design and subsequently build and test six blades using the improved processes and materials. In particular, ABM was interested in reducing blade cost and improving quality. In addition, ABM needed to find a replacement material for the mature Douglas fir used in the manufacturing process. The use of mature Douglas fir is commercially unacceptable because of its limited supply and environmental concerns associated with the use of mature timber. Unfortunately, the bankruptcy of FloWind in June 1997 and a dramatic reduction in AWT sales made it impossible for ABM to complete the full scope of work. However, sufficient research and testing were completed to identify several promising changes in the blade manufacturing process and develop a preliminary design incorporating these changes.
Date: August 1, 1999
Creator: POORE, ROBERT Z.
Object Type: Report
System: The UNT Digital Library
RCRA Post Closure Monitoring and Inspection Report for CAU 91: Area 3 U-3fi Waste Unit, Nevada Test Site for the Period October 1996-1997 (open access)

RCRA Post Closure Monitoring and Inspection Report for CAU 91: Area 3 U-3fi Waste Unit, Nevada Test Site for the Period October 1996-1997

This annual Neutron Soil Moisture Monitoring report provides an analysis and summary for site inspections, meteorological information, and neutron soil moisture monitoring data obtained at the U-3fi Resource Conservation and Recovery Act (RCRA) Unit, located in Area 3 of the Nevada Site (NTS), Nye County, Nevada, during the October 1996-October 1997 period. Inspections of the U-3fi RCRA Unit are conducted to determine and document the physical condition of the concrete pad, facilities, and any unusual conditions that could impact the proper operation of the waste unit closure. The objective of the neutron logging is to monitor the soil moisture conditions along the 128 meter (420 feet) ER3-3 monitoring well and detect changes that may be indicative of moisture movement in the regulated interval extending between 73 m to 82 m (240 to 270 ft).
Date: January 1, 1998
Creator: Emer, Dudley
Object Type: Report
System: The UNT Digital Library
A molecular architectural approach to second-order nonlinear optical materials (open access)

A molecular architectural approach to second-order nonlinear optical materials

Design and synthesis of a family of calix[4]arene-based nonlinear optical (NLO) chromophores are discussed. The calixarene chromophores are macrocyclic compounds consisting These molecules were synthesized such of four simple D-{pi}-A units bridged by methylene groups. These molecules were synthesized such that four D-n-A units of the calix[4]arene were aligned along the same direction with the calixarene in a cone conformation. These nonlinear optical super-chromophores were subsequently fabricated into covalently bound self-assembled monolayers on the surfaces of fused silica and silicon. Spectroscopic second harmonic generation (SHG) measurements were carried out to determine the absolute value of the dominant element of the nonlinear susceptibility, {Chi}{sub zzz}, and the average molecular alignment, {Psi}. We find a value of {Chi}{sub zzz}{approximately} 1.5 {times} 10{sup {minus}7} esu (60 pm/V) at a wavelength of 890 nm, and {Psi} {approximately} 36{degrees} with respect to the surface normal.
Date: September 1, 1995
Creator: Yang, Xiaoguang; McBranch, D.; Swanson, B. & Li, DeQuan
Object Type: Article
System: The UNT Digital Library
Final report for tank 241-U-102, cores 143 and 144 (open access)

Final report for tank 241-U-102, cores 143 and 144

None
Date: August 30, 1996
Creator: Steen, F.H., Westinghouse Hanford
Object Type: Report
System: The UNT Digital Library
Environmental Assessment for the Operation of the Glass Melter Thermal Treatment Unit at the US Department of Energy`s Mound Plant, Miamisburg, Ohio (open access)

Environmental Assessment for the Operation of the Glass Melter Thermal Treatment Unit at the US Department of Energy`s Mound Plant, Miamisburg, Ohio

The glass melter would thermally treat mixed waste (hazardous waste contaminated with radioactive constituents largely tritium, Pu-238, and/or Th-230) that was generated at the Mound Plant and is now in storage, by stabilizing the waste in glass blocks. Depending on the radiation level of the waste, the glass melter may operate for 1 to 6 years. Two onsite alternatives and seven offsite alternatives were considered. This environmental assessment indicates that the proposed action does not constitute a major Federal action significantly affecting the human environment according to NEPA, and therefore the finding of no significant impact is made, obviating the need for an environmental impact statement.
Date: June 1, 1995
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The role of amenities and other factors in influencing the location of nonmanufacturing industry in the United States (open access)

The role of amenities and other factors in influencing the location of nonmanufacturing industry in the United States

Consumer and producer services, the latter in particular, are expected to become an important means of diversification and employment growth to the economy of Nevada. It has been suggested that the siting of the nuclear waste repository at Yucca Mountain, Nevada, will lead to a significant reduction in the amenity value of the state and, consequently, the ability of the state to attract these nonmanufacturing industries. This report reviews the literature dealing with factors important to the location of services, with an emphasis on producer services, to determine whether amenities, which have been shown to be an important locational consideration for some manufacturing firms, similarly affect the location of services. The report finds little substantive evidence to link amenities with the location of service firms, although the process by which these firms` locations are chosen is not well understood. Research in this area is comparatively recent, and although a number of theories of service location have been developed, the majority of research is exploratory in scope.
Date: July 1990
Creator: Allison, T. & Calzonetti, F. J.
Object Type: Report
System: The UNT Digital Library
Validating the role of AFVs in voluntary mobile source emission reduction programs. (open access)

Validating the role of AFVs in voluntary mobile source emission reduction programs.

Late in 1997, EPA announced new allowances for voluntary emission control programs. As a result, the US Department of Energy's (DOE) Clean Cities and other metro areas that have made an ongoing commitment to increasing participation by alternative fuel vehicles (AFVs) in local fleets have the opportunity to estimate the magnitude and obtain emission reduction credit for following through on that commitment. Unexpectedly large reductions in key ozone precursor emissions in key locations and times of the day can be achieved per vehicle-mile by selecting specific light duty AFV offerings from original equipment manufacturers (OEMs) in lieu of their gasoline-fueled counterparts. Additional benefit accrues from the fact that evaporative emissions of non-methane hydrocarbons (generated in the case of CNG, LNG, and LPG by closed fuel-system AFV technology) can be essentially negligible. Upstream emissions from fuel storage and distribution with the airshed of interest are also reduced. This paper provides a justification and outlines a method for including AFVs in the mix of strategies to achieve local and regional improvements in ozone air quality, and for quantifying emission reduction credits. At the time of submission of this paper, the method was still under review by the US EPA Office of Mobile …
Date: March 17, 1999
Creator: Santini, D. J. & Saricks, C. L.
Object Type: Article
System: The UNT Digital Library