Degree Department

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[Notes to financial statements] (open access)

[Notes to financial statements]

A copy of some notes on AIDS ARMS Network's financial statements.
Date: August 31, 1991
Creator: AIDS ARMS Network, Inc.
Object Type: Text
System: The UNT Digital Library
Results from the Soviet-American gallium experiment (open access)

Results from the Soviet-American gallium experiment

A radiochemical {sup 71}Ga-{sup 71}Ge experiment to determine the primary flux of neutrinos from the Sun has begun operation at the Baksan Neutrino Observatory. The number of {sup 71}Ge atoms extracted from thirty tons of gallium was measured in five runs during the period of January to July 1990. Assuming that the extraction efficiency for {sup 71}Ge atoms produced by solar neutrinos is the same as from natural Ge carrier, we observed the capture rate to be 20 + 15/{minus}20 (stat) {plus_minus} 32 (syst) SNU, resulting in a limit of less than 79 SNU (90% CL). This is to be compared with 132 SNU predicted by the Standard Solar Model.
Date: December 31, 1991
Creator: Abazov, A. I.; Anosov, O. L.; Faizov, E. L.; Gavrin, V. N.; Kalikhov, A. V.; Knodel, T. V. et al.
Object Type: Report
System: The UNT Digital Library
Development of novel copper-based sorbents for hot-gas cleanup. Technical report, September 1--November 30, 1991 (open access)

Development of novel copper-based sorbents for hot-gas cleanup. Technical report, September 1--November 30, 1991

The objective of this investigation is to evaluate several novel copper-based binary oxides for their suitability as regenerable sorbents for hot gas cleanup application in the temperature range of 650{degree} to 850{degree}C (1200{degree}--1550{degree}F). To achieve this objective, several novel copper-based binary oxide sorbents will be prepared. Experimental tests will be conducted at ambient pressure to determine the stability, sulfidation capacity, regenerability, and sulfidation kinetics of the novel sorbents. Tests will also be conducted at high pressure for the determination of the sulfidation reactivity, regenerability, and durability of the sorbents. The attrition characteristics of the sorbents will also be determined.
Date: December 31, 1991
Creator: Abbasian, J.
Object Type: Report
System: The UNT Digital Library
Stabilization and/or regeneration of spent sorbents from coal gasification. Technical report, September 1--November 30, 1991 (open access)

Stabilization and/or regeneration of spent sorbents from coal gasification. Technical report, September 1--November 30, 1991

The objective of this investigation is to determine the effects of SO{sub 2} partial pressure and reaction temperature on the conversion of sulfide containing solid wastes from coal gasifiers to stable and environmentally acceptable calcium-sulfate, while preventing the release of sulfur dioxide through undesirable side reactions during the stabilization step. An additional objective of this program is to investigate the use of the Spent Sorbent Regeneration Process (SSRP) to regenerate spent limestone, from a fluidized-bed gasifier with in-bed sulfur capture, for recycling to the gasifier. To achieve these objectives, selected samples of partially sulfided sorbents will be reacted with oxygen at a variety of operating conditions under sufficient SO{sub 2} partial pressure to prevent release of sulfur from the solids during stabilization that reduces the overall sorbent utilization. Partially sulfided limestone will also be regenerated with water to produce calcium hydroxide and release sulfur as H{sub 2}S. The regenerated sorbent will be dewatered, dried and pelletized. The reactivity of the regenerated sorbent toward H{sub 2}S will also be determined. During this quarter sulfidation tests were conducted in a quartz fluidized-bed reactor in which the selected calcium-based sorbents were first calcined and then were reacted with hydrogen sulfide at ambient pressure …
Date: December 31, 1991
Creator: Abbasian, J.
Object Type: Report
System: The UNT Digital Library
[RE: Kennedy Center's ARTSEDGE] (open access)

[RE: Kennedy Center's ARTSEDGE]

Photocopy of a letter from Julie Abel,Program Associate, Getty Center for Education in the Arts, to the Regional Institute Directors. The letter is in regards to the John F. Kennedy Center for the Performing Arts requesting information on "promising programs, multi-media, resources and award programs" to be made available on ARTSEDGE. ArtsEdge, the center's National Arts and Education Information Network. Attached to the email is a document in regards to The Kennedy's Centers program.
Date: August 31, 1991
Creator: Abel, Julie
Object Type: Letter
System: The UNT Digital Library
A novel approach to highly dispersing catalytic materials in coal for gasification. Eighth quarterly report, July 1, 1991--September 30, 1991 (open access)

A novel approach to highly dispersing catalytic materials in coal for gasification. Eighth quarterly report, July 1, 1991--September 30, 1991

This project seeks to develop a technique, based on coal surface properties, for highly dispersing catalysts in coal for gasification and to investigate the potential of using potassium carbonate and calcium acetate mixtures as catalyst for coal gasification. The lower cost and high catalytic activity of the latter compound will produce economic benefits by reducing the amount of K{sub 2}CO{sub 3} required for high coal char activities. The effects of potassium impregnation conditions (pH and coal surface charge) on the reactivities, in carbon dioxide, of chars derived from demineralized lignite, subbituminous and bituminous coals have been determined. Impregnation of the acid-leached coal with potassium from strongly acidic solutions resulted in initial slow char reactivity which progressively increased with reaction time. Higher reactivities were obtained for catalyst (potassium) loaded at pH 6 or 10. The dependence of char gasification rates on catalyst addition pH increased in the order: pH 6 {approximately} pH 10 {much_gt} pH 1.
Date: December 31, 1991
Creator: Abotsi, G. M. K. & Bota, K. B.
Object Type: Report
System: The UNT Digital Library
Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst. Technical progress reports No. 7 and 8, April 1, 1991--September 30, 1991 (open access)

Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst. Technical progress reports No. 7 and 8, April 1, 1991--September 30, 1991

The objective of this contract is to examine the relationship between catalytic properties and the function of cobalt Fischer-Tropsch catalysts and to apply this fundamental knowledge to the development of a stable cobalt-based catalyst with a low methane-plus-ethane selectivity for use in slurry reactors. An experimental cobalt catalyst 585R2723 was tested three times in the fixed-bed reactor. The objective of the tests was to identify suitable testing conditions for screening catalyst. The {alpha}-alumina was determined to be a suitable diluent medium for controlling the catalyst bed temperature close to the inlet temperature. With 13 g of catalyst and 155 g of diluent, the catalyst maximum temperature were within 2{degree}C from the inlet temperatures. As a result of this work, 210{degree}C and 21 atm were shown to result in low methane selectivity and were used as initial conditions in the catalyst screening test. Ethane, which along with methane is undesirable, is typically produced with low selectivity and follows the same trend as methane. Other work reported here indicated that methane selectivity increases with increasing temperature but is not excessively high at 230{degree}C. Consequently, the catalyst screening test should include an evaluation of the catalyst performance at 230{degree}C. During Run 67, the …
Date: December 31, 1991
Creator: Abrevaya, H.
Object Type: Report
System: The UNT Digital Library
Chronic lung injury risk estimates for urban areas having ozone patterns similar to those in the Northeast (open access)

Chronic lung injury risk estimates for urban areas having ozone patterns similar to those in the Northeast

This paper describes the approach and result of an assessment of health risks associated with long-term exposure to ozone. The health endpoint of interest is the probability of formation of mild lesions in the centriacinar region of the lung among children living in New York City. The risk model incorporates an exposure model and a health model. The exposure model is preliminary results of the probabilistic NAAQS Exposure Model (P-NEM) for ozone, and the health model is the judgments of active researchers about the likelihood of formation of ozone-induced lesions in the human lung. Children and New York City were chosen as the population and city of interest because it is believed that children are more sensitive to ozone than any other group of people, and New York City is more representative of other urban areas than Los Angeles, the other city of which P-NEM exposure results are available. Risk results are presented for ten exposure distributions generated by P-NEM, two air quality scenarios (``as-is`` and ``attainment``), and two exposure periods (1 and 10 ozone seasons). The results vary across experts, are not very sensitive to variations in P-NEM exposure distributions, are lower for attainment conditions than as-is conditions, and …
Date: December 31, 1991
Creator: Absil, M.; Narducci, P.; Whitfield, R. & Richmond, H. M.
Object Type: Article
System: The UNT Digital Library
Plutonium recovery from spent reactor fuel by uranium displacement (open access)

Plutonium recovery from spent reactor fuel by uranium displacement

This report discusses a process for separating uranium values and transuranic values from fission products containing rare earth values when the values which are contained together in a molten chloride salt electrolyte. A molten chloride salt electrolyte with a first ratio of plutonium chloride to uranium chloride is contacted with both a solid cathode and an anode having values of uranium and fission products including plutonium. A voltage is applied across the anode and cathode electrolytically to transfer uranium and plutonium from the anode to the electrolyte while uranium values in the electrolyte electrolytically deposit as uranium metal on the solid cathode in an amount equal to the uranium and plutonium transferred from the anode causing the electrolyte to have a second ratio of plutonium chloride to uranium chloride. Then the solid cathode with the uranium metal deposited thereon is removed and molten cadmium having uranium dissolved therein is brought into contact with the electrolyte resulting in chemical transfer of plutonium values from the electrolyte to the molten cadmium and transfer of uranium values from the molten cadmium to the electrolyte until the first ratio of plutonium chloride to uranium chloride is re-established.
Date: December 31, 1991
Creator: Ackerman, J. P.
Object Type: Patent
System: The UNT Digital Library
Magnesium transport extraction of transuranium elements from LWR fuel (open access)

Magnesium transport extraction of transuranium elements from LWR fuel

This report discusses a process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels which contain rare earth and noble metal fission products. The oxide fuel is reduced with Ca metal in the presence of CaCl{sub 2} and a U-Fe alloy containing not less than about 84% by weight uranium at a temperature in the range of from about 800{degrees}C to about 850{degrees}C to produce additional uranium metal which dissolves in the U-Fe alloy raising the uranium concentration and having transuranium actinide metals and rare earth fission product metals and the noble metal fission products dissolved therein. The CaCl{sub 2} having CaO and fission products of alkali metals and the alkali earth metals and iodine dissolved therein is separated and electrolytically treated with a carbon electrode to reduce the CaO to Ca metal while converting the carbon electrode to CO and CO{sub 2}. The Ca metal and CaCl{sub 2} is recycled to reduce additional oxide fuel. The U-Fe alloy having transuranium actinide metals and rare earth fission product metals and the noble metal fission products dissolved therein is contacted with Mg metal which takes up the actinide and rare earth fission product metals. The U-Fe …
Date: December 31, 1991
Creator: Ackerman, J. P.; Battles, J. E.; Johnson, T. R.; Miller, W. E. & Pierce, R. D.
Object Type: Patent
System: The UNT Digital Library
INEL BNCT Program: Volume 5, No. 9. Bulletin, September 1991 (open access)

INEL BNCT Program: Volume 5, No. 9. Bulletin, September 1991

This Bulletin presents a summary of accomplishments and highlights of the Idaho National Engineering Laboratory`s (INEL) Boron Neutron Capture Therapy (BNCT) Program for September 1991. This bulletin includes information on the brain tumor and melanoma research programs, Power Burst Facility (PBF) technical support and modifications, PBF operations, and updates to the animal data charts.
Date: December 31, 1991
Creator: Ackermann, A. L.
Object Type: Report
System: The UNT Digital Library
An analytical assessment of the chemical form of fission products during postulated severe accidents in the SRS production reactors (open access)

An analytical assessment of the chemical form of fission products during postulated severe accidents in the SRS production reactors

An analysis has been performed to determine the principal chemical forms for the structural and fission product elements during a postulated severe core damage accident in tritium powered core in the Savannah River Site (SRS) reactors. These reactors are powered with UAl{sub x} fuel and are used for the production of weapons materials. Six core elements, cesium, iodine, tellurium, strontium, barium, and lithium, were emphasized in this analysis. Other elements also included were aluminum, hydrogen, oxygen, uranium, molybdenum, silicon, zirconium, magnesium, iron, chromium, nickel, cadmium, zinc, cooper, manganese, nitrogen, and argon. The masses of each of the constituents used in the analyses were based on end-or-core life masses for the structural and fission product elements and on core gas volume for steam, N, and Ar. A chemical equilibrium analysis was performed using the Facility for Analysis of Chemical Thermodynamics (FACT) computer code at three temperatures (800, 1100, 1400 K) and two pressures (1 and 10 atmospheres). These temperatures and pressures are typical for postulated severe core accidents in the ATR.
Date: December 31, 1991
Creator: Adams, J. P.
Object Type: Article
System: The UNT Digital Library
Fission product transport and behavior during two postulated loss of flow transients in the air (open access)

Fission product transport and behavior during two postulated loss of flow transients in the air

This document discusses fission product behavior during two postulated loss-of-flow accidents (leading to high- and low-pressure core degradation, respectively) in the Advanced Test Reactor (ATR). These transients are designated ATR Transient LCPI5 (high-pressure) and LPP9 (low-pressure). Normally, transients of this nature would be easily mitigated using existing safety systems and procedures. In these analyses, failure of these safety systems was assumed so that core degradation and fission product release could be analyzed. A probabilistic risk assessment indicated that the probability of occurrence for these two transients is of the order of 10{sup {minus}5 }and 10{sup {minus}7} per reactor year for LCP15 and LPP9, respectively.
Date: December 31, 1991
Creator: Adams, J. P. & Carboneau, M. L.
Object Type: Article
System: The UNT Digital Library
Advanced Processing Technology semiannual report, March--December 1991. Volume 1, Number 1 (open access)

Advanced Processing Technology semiannual report, March--December 1991. Volume 1, Number 1

This first issue of the APT Semiannual Report focuses on APT`s defense-related technologies. These technologies are a continuation of the research, development, and engineering work performed by LLNLs Special Isotope Separation (SIS) Program. SIS was the first large-scale DOE venture that had environmentally conscious manufacturing processes and facilities as its deliverables. The objectives were to create a facility where the only outputs were either usable products or disposable wastes, and to comply with existing and anticipated federal, state, and local regulations related to safeguards, security, health and safety. To meet these objectives, revolutionary changes were needed in plutonium processing operations, chemistry, and equipment. New processes had to be developed that enhanced worker safety, minimized operator radiation dose, minimized waste at the point of generation, and provided for built-in recycling of residues. The SIS Program developed and demonstrated the technology (both chemistry and physics) necessary to provide plutonium with individual isotopic tailoring. This process made it possible to transform fuel-grade plutonium into weapon-grade material. However, due to the changing world political climate, the country`s need for plutonium to make new weapons has decreased dramatically. As a result, the planned SIS plutonium-separation plant will not be built. After the SIS Program was …
Date: December 31, 1991
Creator: Adamson, M. & Kline-Simon, K.
Object Type: Report
System: The UNT Digital Library
Harvard-MIT research program in short-lived radiopharmaceuticals. Technical progress report, 1991 (open access)

Harvard-MIT research program in short-lived radiopharmaceuticals. Technical progress report, 1991

This report presents research on radiopharmaceuticals. The following topics are discussed: antibody labeling with positron-emitting radionuclides; antibody modification for radioimmune imaging; labeling antibodies; evaluation of technetium acetlyacetonates as potential cerebral blood flow agents; and studies in technetium chemistry. (CBS)
Date: December 31, 1991
Creator: Adelstein, S. J.
Object Type: Report
System: The UNT Digital Library
A computational model for coal transport and combustion. Quarterly technical progress report, September 1--November 30, 1991 (open access)

A computational model for coal transport and combustion. Quarterly technical progress report, September 1--November 30, 1991

During the last three months, considerable progress has been made in formulation of the thermodynamically consistent rate dependent model for turbulent two-phase flows. The basic governing equations were derived and the case of a simple shear flow was also analyzed. Preliminary comparisons with the available experimental data were also performed. The thermodynamical approach was successfully formulated for developing a stress transport model for granular flows. The appropriate constitutive equations were derived and it was shown that the model contains the existing kinetic theory results as special limiting cases. The formulation also allows for the possible rotation of the frame of reference. Using a kinetic-based model which includes frictional losses, several rapid granular shear flows including Couette and gravity flows were analyzed. Preliminary comparisons with experimental data were also performed. The experimental setup for the simple shear flow device is being designed. The procedure for constructing the device is being studied.
Date: December 31, 1991
Creator: Ahmadi, G.
Object Type: Report
System: The UNT Digital Library
Novel reactor configuration for synthesis gas conversion to alcohols. Quarterly report, July 1, 1991--September 30, 1991 (open access)

Novel reactor configuration for synthesis gas conversion to alcohols. Quarterly report, July 1, 1991--September 30, 1991

Our objectives during this quarter were to complete construction and shake down runs on our new reactor assemblies, obtain activity data on the catalyst employing the slurry reactor, incorporate pressure drop and change in number of moles options into our reactor simulation code and start experiments in the trickle bed reactor.
Date: December 31, 1991
Creator: Akgerman, A. & Anthony, R. G.
Object Type: Report
System: The UNT Digital Library
Vibration monitoring of EDF rotating machinery using artificial neural networks (open access)

Vibration monitoring of EDF rotating machinery using artificial neural networks

Vibration monitoring of components in nuclear power plants has been used for a number of years. This technique involves the analysis of vibration data coming from vital components of the plant to detect features which reflect the operational state of machinery. The analysis leads to the identification of potential failures and their causes, and makes it possible to perform efficient preventive maintenance. Earlydetection is important because it can decrease the probability of catastrophic failures, reduce forced outgage, maximize utilization of available assets, increase the life of the plant, and reduce maintenance costs. This paper documents our work on the design of a vibration monitoring methodology based on neural network technology. This technology provides an attractive complement to traditional vibration analysis because of the potential of neural networks to operate in real-time mode and to handle data which may be distorted or noisy. Our efforts have been concentrated on the analysis and classification of vibration signatures collected by Electricite de France (EDF). Two neural networks algorithms were used in our project: the Recirculation algorithm and the Backpropagation algorithm. Although this project is in the early stages of development it indicates that neural networks may provide a viable methodology for monitoring and …
Date: December 31, 1991
Creator: Alguindigue, I. E.; Loskiewicz-Buczak, A.; Uhrig, R. E.; Hamon, L. & Lefevre, F.
Object Type: Article
System: The UNT Digital Library
In situ transmission electron microscope studies of irradiation-induced and irradiation-enhanced phase changes (open access)

In situ transmission electron microscope studies of irradiation-induced and irradiation-enhanced phase changes

Motivated at least initially by materials needs for nuclear reactor development, extensive irradiation effects studies employing TEMs have been performed for several decades, involving irradiation-induced and irradiation-enhanced, microstructural changes, including phase transformations such as precipitation, dissolution, crystallization, amorphization, and order-disorder phenomena. From the introduction of commercial high voltage electron microscopes (HVEM) in the mid-1960s, studies of electron irradiation effects have constituted a major aspect of HVEM application in materials science. For irradiation effects studies two additional developments have had particularly significant impact: (1) The availability of TEM specimen holders in which specimen temperature can be controlled in the range 10--2200 K; and (2) the interfacing of ion accelerators which allows in situ TEM studies of irradiation effects and the ion beam modification of materials within this broad temperature range. This paper treats several aspects of in situ studies of electron and ion beam-induced and enhanced phase changes, including the current state of in situ ion beam capability internationally, and presents two case studies involving in situ experiments performed in an HVEM to illustrate the dynamics of such an approach in materials research.
Date: December 31, 1991
Creator: Allen, C. W.
Object Type: Article
System: The UNT Digital Library
The importance of trade in services and environmental amenities to the location of producer service activities in the western United States (open access)

The importance of trade in services and environmental amenities to the location of producer service activities in the western United States

The use of business services has had an increasingly important effect on economic performance in many industries, with the ability of firms in a given location to respond to changes in external markets, production techniques and material supplies often determined by the local provision of business information. Consequently, an increasing research effort has focused on the characteristics and role of producer services activities at the regional and urban economies. This paper examines the nature and extent of external linkages of a sample of independent producer service firms in the two regional centers of Denver and Salt Lake City. Preliminary results are presented from a larger survey of local and regional factors important to the location of producer service activity using survey data collected from producer service activities in metropolitan and non-metropolitan places in Colorado and Utah. Findings are presented in three main areas of interest: the importance and geographic sources of subcontracting of business services by producer service establishments, particularly those establishments where scientific and technical occupations are an important location factor; the geographic and sectoral distribution of service sales; and the relative importance of various environmental amenities to the location of producer service activities.
Date: December 31, 1991
Creator: Allison, T.
Object Type: Report
System: The UNT Digital Library
Separation of metal ions from aqueous solutions (open access)

Separation of metal ions from aqueous solutions

This invention is comprised of a process and apparatus for quantitatively and selectively separating metal ions from mixtures thereof in aqueous solution. The apparatus includes, in combination, a horizontal electrochemical flowing cell containing flowing bulk electrolyte solution and an aqueous, metal ion-containing solution, the cell containing a metal mesh working electrode, a counter electrode positioned downstream from the working electrode, an independent variable power supply/potentiostat positioned outside of the flowing cell and connected to the electrodes, and optionally a detector such as a chromatographic detector, positioned outside the flowing cell. This apparatus and its operation has significant application where trace amounts of metal ions are to be separated.
Date: December 31, 1991
Creator: Almon, A.
Object Type: Patent
System: The UNT Digital Library
Multimodal separation of alkali, alkaline earth, transition, post-transition, lanthanide, and actinide metal cations in waste sludge (open access)

Multimodal separation of alkali, alkaline earth, transition, post-transition, lanthanide, and actinide metal cations in waste sludge

An ion chromatographic method, which separates 36 different cations in a single chromatographic run, was developed to separate and analyze trace radionuclides present on high level radioactive waste samples. The method employs linear and step gradients and isocratic elution using four different eluents in six different eluent phases. The separation takes 45 minutes and has detection limits ranging from 0.1 ppM to 5.0 ppM, when using spectrophotometric detection for nonradioactive cations, depending on the sample matrix. The detection limits and relative standard deviation of the data are dependent upon the element and sample matrix. This method can be reliably performed in the laboratory if properly prepared samples are used. This study describes the applications, limitations, interferences, precision, and accuracy of this method. Using this method, trace radionuclides, which are present in concentrations of only a few hundred disintegrations per minute per milliliter, can be separated and then analyzed by using liquid scintillation counting analysis and inductively coupled plasma mass spectrometry (ICP-MS). This paper will first describe the chromatographic separation as it was developed and applied to the analysis of aqueous samples with low ppM levels of nonradioactive cations. Next, the application of this method to the separation and analysis of …
Date: December 31, 1991
Creator: Almon, A. C.; Kinard, W. F.; Dewberry, R. A. & Bibler, N. E.
Object Type: Article
System: The UNT Digital Library
Oil/gas separator for installation at burning wells (open access)

Oil/gas separator for installation at burning wells

An oil/gas separator is disclosed that can be utilized to return the burning wells in Kuwait to production. Advantageously, a crane is used to install the separator at a safe distance from the well. The gas from the well is burned off at the site, and the oil is immediately pumped into Kuwait`s oil gathering system. Diverters inside the separator prevent the oil jet coming out of the well from reaching the top vents where the gas is burned. The oil falls back down, and is pumped from an annular oil catcher at the bottom of the separator, or from the concrete cellar surrounding the well.
Date: December 31, 1991
Creator: Alonso, C. T.; Bender, D. A. & Bowman, B. R.
Object Type: Patent
System: The UNT Digital Library
Exploitation of vertex detection at the Tevatron. Progress report (open access)

Exploitation of vertex detection at the Tevatron. Progress report

None
Date: December 31, 1991
Creator: Amidei, D. E.
Object Type: Report
System: The UNT Digital Library