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Drying Results of K-Basin Damaged/Corroded SNF Internal Sludge and Surface Coating
Experiments were performed using a thermogravimetric analysis (TGA) system by Pacific Northwest National Laboratory (PNNL)to study the drying behavior of the K-Basin spent nuclear fuel (SNF) internal sludge and two different surface coatings of SNF elements. These measurements were conducted in support of the safety and process analyses of the proposed Integrated Process Strategy (IPS) to move the N-Reactor fuel stored at K-Basin to an interim storage facility. These limited experiments on the corrosion products of K-Basin SNF material were part of the broad studies performed to ascertain the bounding pressurization of the Multi-Canister Overpack (MCO). Seven SNF internal sludge samples taken from different damage regions of three damaged/corroded outer K-Basin SNF elements were dried. Additionally, two surface coating samples taken from two SNF elements stored at K-West were tested. All the tests were performed in a vacuum atmosphere with the same temperature ramp rate of about 0.4 C/ min. Each TGA test sample was weighed before and after the test on a balance located in the Shielded Analytical Laboratory hot cell. The test samples were vacuum dried in the TGA system for about 24 hours prior to heating them at the rate of 0.4 C/min. The observations from the …
Date:
September 21, 2000
Creator:
Abrefah, J.; Alexander, D. L. & Marschman, S. C.
Object Type:
Report
System:
The UNT Digital Library
Polycube oxidation and factors affecting the concentrations of gaseous products
The polycubes stored at the Hanford Plutonium Finishing Plant (PFP) have been identified in a Vulnerability Assessment as material that requires a stabilization process in support of the Defense Nuclear Facility Safety Board Recommendation 94-1. The baseline plan involves a pyrolysis process to separate out the plutonium and uranium oxides before the remaining material is packaged for interim storage, in accordance with the Record of Decision (ROD), issued June 25, 1996, for the Plutonium Finishing Plant Stabilization Final Environmental Impact Statement, DOE/EIS-0244-F. The polycubes were manufactured at Hanford in the 1960s for use in criticality studies to determine the hydrogen-to-fissile atom ratios for neutron moderation. A mixture of plutonium and/or uranium oxides and a polystyrene (vinyl benzene) matrix, cast into the shape of cubes, the polycubes simulated solutions containing high concentrations of fissile materials. The polycubes varied in size, typically 1/2 x 2 x 2 in. up to 2 x 2 x 2 in., and were sealed with a coating of aluminum paint and/or tape (PVC or Shurtape). The estimated 1,600 polycubes (calculated 179,165 grams net weight) stored at PFP were packed in vented food cans with five to eight cubes per can to accommodate gas generation by radiolysis. Some …
Date:
May 4, 2000
Creator:
Abrefah, J.; MacFarlan, P. J. & Sell, R. L.
Object Type:
Report
System:
The UNT Digital Library
Thermal Decomposition of Radiation-Damaged Polystyrene
The radiation-damaged polystyrene (given the identification name of 'polycube') was fabricated by mixing high-density polystyrene material ("Dylene Fines # 100") with plutonium and uranium oxides. The polycubes were used in the 1960s for criticality studies during processing of spent nuclear fuel. The polycubes have since been stored for almost 40 years at the Hanford Plutonium Finishing Plant (PFP) after failure of two processes to reclaim the plutonium and uranium oxides from the polystyrene matrix. Thermal decomposition products from this highly cross-linked polystyrene matrix were characterized using Gas Chromatograph/Mass Spectroscopy (GC/MS) system coupled to a horizontal furnace. The decomposition studies were performed in air and helium atmospheres at about 773 K. The volatile and semi-volatile organic products for the radiation-damaged polystyrene were different compared to virgin polystyrene. The differences were in the number of organic species generated and their concentrations. In the inert (i.e., helium) atmosphere, the major volatile organic products identified (in order of decreasing concentrations) were styrene, benzene, toluene, ethylbenzene, xylene, nathphalene, propane, .alpha.-methylbenzene, indene and 1,2,3-trimethylbenzene. But in air, the major volatile organic species identified changed slightly. Concentrations of the organic species in the inert atmosphere were significantly higher than those for the air atmosphere processing. Overall, 38 …
Date:
September 26, 2000
Creator:
Abrefah, John & Klinger, George S.
Object Type:
Report
System:
The UNT Digital Library
Polycube Oxidation and Factors Affecting the Concentrations of Gaseous Products
The degraded polycube samples were tested in air and argon/oxygen atmospheres to determine the effect of size increase on the flammable gases concentrations. Within the size range tested, the flammable gas generation rate increases with increasing size but the extrapolation of the data to actual processing polycube size yielded flammable gas species concentration in the off-gas stream below the lower flammable limit of all the major gas species identified. Extreme surface area increase with a powder sample showed no significant effect on the flammable gas generation rate. The polycube went through the thermal stabilization process by undergoing both pyrolysis and oxidation generating at the end a plutonium oxide powder that showed unmeasurable weight change at 1273 K.
Date:
April 4, 2000
Creator:
Abrefah, John; MacFarlan, Paul J. & Sell, Rachel L.
Object Type:
Text
System:
The UNT Digital Library
The Migration and Entrapment of DNAPLs in Physically and Chemically Heterogeneous Porous Media - Final Report - 09/15/1996 - 09/15/2000
Hazardous dense nonaqueous phase liquids (DNAPLs), such as chlorinated solvents, are slightly water soluble and pose a serious threat to soil and groundwater supplies in many portions of the United States. The migration and entrapment of DNAPLs in the subsurface environment is typically believed to be controlled by physical heterogeneities; i.e, layers and lenses of contrasting soil texture. The rationale for this assumption is that capillarity, as determined by the soil texture, is the dominant transport mechanism. Capillarity also depends on interfacial tension and medium wettability. Interfacial tension and medium wettability may be spatially and temporally dependent due to variations in aqueous phase chemistry, contaminant aging, and/or variations in mineralogy and organic matter distributions. Such chemical heterogeneities have largely been ignored to date, even though they are known to have dramatic effects on the hydraulic property relations. Numerical multiphase flow and transport models typically assume that solids are water-wet and that interfacial tension is constant. The primary objective of this research is to investigate the influence of coupled physical and chemical heterogeneities on the migration and entrapment of DNAPLs. This objective will be accomplished through a combination of laboratory and numerical experiments. Laboratory experiments will be conducted to examine: (i) …
Date:
September 15, 2000
Creator:
Abriola, L. M. & Demond, A. H.
Object Type:
Report
System:
The UNT Digital Library
The Migration and Entrapment of DNAPLs in Physically and Chemically Heterogeneous Porous Media
This document summarizes EMSP funded research designed to improve our understanding of and ability to simulate the influence of subsurface chemical heterogeneities on DNAPL flow and entrapment in the saturated zone. Specific project objectives include: (i) the quantification of DNAPL interfacial and hydraulic properties; (ii) development and assessment of constitutive hydraulic property and continuum based multiphase flow models; (iii) exploration of DNAPL migration and entrapment in heterogeneous systems at larger scales; and (iv) development of innovative remediation schemes.
Date:
June 1, 2000
Creator:
Abriola, Linda M. & Demond, Avery H.
Object Type:
Report
System:
The UNT Digital Library
EARLY ENTRANCE COPRODUCTION PLANT
The overall objective of this project is the three phase development of an Early Entrance Coproduction Plant (EECP) which produces at least one product from at least two of the following three categories: (1) electric power (or heat), (2) fuels, and (3) chemicals. The objective is to have these products produced by technologies capable of using synthesis gas derived from coal and/or other carbonaceous feedstock. The objective of Phase I is to determine the feasibility and define the concept for the EECP located at a specific site and to develop a Research, Development, and Testing Plan (RD and T) for implementation in Phase II. The objective of Phase II is to implement the RD and T as outlined in the Phase I RD and T Plan to enhance the development and commercial acceptance of coproduction technology that produces high-value products, particularly those that are critical to our domestic fuel and power requirements. The project will resolve critical knowledge and technology gaps on the integration of gasification and downstream processing to coproduce some combination of power, fuels, and chemicals from coal and other feedstocks. The objective of Phase III is to develop an engineering design package and a financing plan for …
Date:
October 26, 2000
Creator:
Abughazaleh, John S.; Ahmed, Mushtaq; Anand, Ashok; Anderson, John H.; Benham, Charles; Brent, Fred D. et al.
Object Type:
Report
System:
The UNT Digital Library
A Sequential Fluid-mechanic Chemical-kinetic Model of Propane HCCI Combustion
We have developed a methodology for predicting combustion and emissions in a Homogeneous Charge Compression Ignition (HCCI) Engine. This methodology combines a detailed fluid mechanics code with a detailed chemical kinetics code. Instead of directly linking the two codes, which would require an extremely long computational time, the methodology consists of first running the fluid mechanics code to obtain temperature profiles as a function of time. These temperature profiles are then used as input to a multi-zone chemical kinetics code. The advantage of this procedure is that a small number of zones (10) is enough to obtain accurate results. This procedure achieves the benefits of linking the fluid mechanics and the chemical kinetics codes with a great reduction in the computational effort, to a level that can be handled with current computers. The success of this procedure is in large part a consequence of the fact that for much of the compression stroke the chemistry is inactive and thus has little influence on fluid mechanics and heat transfer. Then, when chemistry is active, combustion is rather sudden, leaving little time for interaction between chemistry and fluid mixing and heat transfer. This sequential methodology has been capable of explaining the main …
Date:
November 29, 2000
Creator:
Aceves, S M; Flowers, D L; Martinez-Frias, J; Smith, J R; Westbrook, C; Pitz, W et al.
Object Type:
Article
System:
The UNT Digital Library
Low Temperature and High Pressure Evaluation of Insulated Pressure Vessels for Cryogenic Hydrogen Storage
Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The work described here is directed at verifying that commercially available pressure vessels can be safely used to store liquid hydrogen. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analysis and experiments to date indicate that no significant damage has resulted. Required future tests are described that will prove that no technical barriers exist to the safe use of aluminum-fiber vessels at cryogenic temperatures.
Date:
June 25, 2000
Creator:
Aceves, S.; Martinez-Frias, J. & Garcia-Villazana, O.
Object Type:
Article
System:
The UNT Digital Library
Numerical and Experimental Studies of HCCI combustion
None
Date:
August 20, 2000
Creator:
Aceves, Salvador M.
Object Type:
Article
System:
The UNT Digital Library
The Meaning of Elder Abuse
Access:
Use of this item is restricted to the UNT Community
Elder abuse first received national attention in 1980, as the subject of a congressional investigation. Now, 20 years later, establishing successful strategies of identification, subsequent intervention, and prevention of abuse is of paramount importance; but progress toward this goal is hindered by lack of consensus as to the definition of elder abuse, and the use of vague, confusing, and sometimes contradictory terms in its discussion. In this paper, both social research and professional approaches and legal approaches to the definition of elder abuse are surveyed, as are definitions formulated for the National Elder Abuse Incidence Study conducted by the National Center on Elder Abuse. The continuing need for a universal or standard definition is emphasized.
Date:
May 2000
Creator:
Achilli, Raye
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
ENSO Simulation in CGCMs and the Associated Errors in Atmospheric Response
Tropical Pacific variability, and specifically the simulation of ENSO in coupled ocean-atmosphere general circulation models (CGCMs) has previously been assessed in many studies (McCreary and Anderson [1991], Neelin et al. [1992], Mechoso et al. [1995], Latif et al. [2000], and Davey et al. [2000]). These studies have concentrated on SST variations in the tropical Pacific, and discussions of the atmospheric response have been limited to east-west movements of the convergence zone. In this paper we discuss the large-scale atmospheric response to simulated ENSO events. Control simulations from 17 global CGCMs from CMIP (Meehl et al. [2000]) are studied. The web site http:// www-pcmdi.llnl.gov/cmip/modeldoc provides documentation of the configurations of the models.
Date:
September 11, 2000
Creator:
AchutaRao, K. & Sperber, K.R.
Object Type:
Article
System:
The UNT Digital Library
Reduction of Tropical Cloudiness by Soot
Measurements and models show that enhanced aerosol concentrations can augment cloud albedo not only by increasing total droplet cross-sectional area, but also by reducing precipitation and thereby increasing cloud water content and cloud coverage. Aerosol pollution is expected to exert a net cooling influence on the global climate through these conventional mechanisms. Here we demonstrate an opposite mechanism through which aerosols can reduce cloud cover and thus significantly offset aerosol-induced radiative cooling at the top of the atmosphere on a regional scale. In model simulations the daytime clearing of trade cumulus is hastened and intensified by solar heating in dark haze (as found over much of the northern Indian Ocean during the northeast monsoon).
Date:
May 8, 2000
Creator:
Ackerman, A. S.; Toon, O. B.; Stevens, D. E.; Heymsfield, A. J. & Ramanathan, V.
Object Type:
Report
System:
The UNT Digital Library
Charitable Choice: Constitutional Issues and Developments Through the 106th Congress
This report is about the charitable choice of constitutional issues and developments through the 106th congress.
Date:
December 27, 2000
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
Education Vouchers: Constitutional Issues and Cases
This report details the constitutional standards that currently apply to indirect aid programs and summarizes all of the pertinent state and federal court decisions, including the Ohio case that will be heard by the Supreme Court. On September 25, 2001, the Supreme Court agreed to review a case raising the controversial issue of the constitutionality of education vouchers. In Zelman v. Simmons-Harris the Sixth Circuit held Ohio’s Pilot Scholarship Program, which provided up to $2500 to help low-income students in Cleveland’s public schools attend private schools in the city, to violate the establishment of religion clause of the First Amendment.
Date:
December 19, 2000
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
The Law of Church and State: Public Aid to Sectarian Schools
One of the most difficult issues of constitutional law concerns the extent to which the establishment of religion clause of the First Amendment imposes constraints on the provision of public aid to private sectarian schools. This report gives a brief overview of the evolution of the Court’s interpretation of the establishment clause in this area and itemizes the categories of aid that have been addressed by the Court and held to be constitutionally permissible or impermissible, both at the elementary and secondary school level and at the college level.
Date:
August 1, 2000
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
Prayer and Religion in the Public Schools: What Is, and Is Not, Permitted
This report summarizes each of the Supreme Courts decisions in regard to instances of prayer and religion in public schools. The report gives a detailed overview of what has been held to be constitutionally permissible and constitutionally forbidden, and describes two issues as yet unsettled.
Date:
August 18, 2000
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
Applying Overseas Missions Strategies Across Town
Lecture given Monday, February 21, 2000, 8:30 AM at Abilene Christian University: "If we can plant growing churches in Latin America, why not get local Spanish evangelistic efforts off and running?"
Date:
February 21, 2000
Creator:
Acosta, Albert
Object Type:
Sound
System:
The Portal to Texas History
The Nuts and Bolts of Growing Hispanic Works
Lecture given Monday, February 21, 2000, 11:00 AM at Abilene Christian University: "If we can plant growing churches in Latin America, why not get local Spanish evangelistic efforts off and running?"
Date:
February 21, 2000
Creator:
Acosta, Albert
Object Type:
Sound
System:
The Portal to Texas History
A Theology for Working with Hispanics
Lecture given Monday, February 21, 2000, 3:30 PM at Abilene Christian University: "If we can plant growing churches in Latin America, why not get local Spanish evangelistic efforts off and running?"
Date:
February 21, 2000
Creator:
Acosta, Albert
Object Type:
Sound
System:
The Portal to Texas History
Leptoquark searches at the Tevatron
The authors report on searches for leptoquarks using approximately 100 pb {sup -1} of data collected by CDF and DO during Run I at the Tevatron. They also present searches for resonantly-produced leptoquarks that arise in technicolor models. Prospects for future leptoquark searches using Run II data are also discussed.
Date:
June 23, 2000
Creator:
Acosta, Darin E.
Object Type:
Article
System:
The UNT Digital Library
Comments concerning the 'solubility of buckminsterfullerene in tetrahydrofuran, thiophene, tetrahydrothiophene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene and n-butylamine'
Article commenting on the 'solubility of buckminsterfullerene in tetrahydrofuran, thiophene, tetrahydrothiophene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene and n-butylamine.'
Date:
September 2000
Creator:
Acree, William E. (William Eugene)
Object Type:
Article
System:
The UNT Digital Library
Comments on the paper entitled "Determination of the equilibrium constant for complex formation in a binary mixture of chloroform and triethylamine from viscosity data on the basis of the ideal associated solution model"
Article commenting on the paper entitled "Determination of the equilibrium constant for complex formation in a binary mixture of chloroform and triethylamine from viscosity data on the basis of the idea associated solution model"
Date:
April 2000
Creator:
Acree, William E. (William Eugene)
Object Type:
Article
System:
The UNT Digital Library
First year operational experience with the Cherenkov Detector (DIRC) of BaBar
The DIRC (acronym for Detection of Internally Reflected Cherenkov (light)) is a new type of Cherenkov ring imaging detector based on total internal reflection that is used for the first time in the BaBar detector at PEP-II ring of SLAC. The Cherenkov radiators are long rectangular bars made of synthetic fused silica. The photon detector is a water tank equipped with an array of 10,752 conventional photomultipliers. The first year operational experience in the BaBar detector is presented using cosmic data and collision data in the energy region of the Y(4s) resonance.
Date:
April 1, 2000
Creator:
Adam, I. & Collaboration, BaBar
Object Type:
Article
System:
The UNT Digital Library