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[HIV Health Services Planning Council] (open access)

[HIV Health Services Planning Council]

A reactive publication from the HIV Health Services Planning Council in response to the Ryan White C.A.R.E. Act of 1990.
Date: December 20, 1990
Creator: AIDS Arms Network, Inc.
Object Type: Text
System: The UNT Digital Library
[Fax: Clinton administration seeking increase in AIDS funding] (open access)

[Fax: Clinton administration seeking increase in AIDS funding]

A fax from the AIDS Services of Dallas to the Voice discussing the Clinton administration protecting and seeking to increase healthcare funding for people with HIV/AIDS.
Date: December 21, 1994
Creator: AIDS Service Dallas
Object Type: Text
System: The UNT Digital Library
[Fax: Memorandum and News Story] (open access)

[Fax: Memorandum and News Story]

A fax from the AIDS Services of Dallas to Scott Mackey at the Dallas Voice about an increase in funding for programs that assist persons with HIV/AIDS.
Date: December 21, 1994
Creator: AIDS Services of Dallas
Object Type: Text
System: The UNT Digital Library
[News release with handwritten notes: The President is planning to terminate HOPWA] (open access)

[News release with handwritten notes: The President is planning to terminate HOPWA]

A copy of a newspaper clipping and news release concerning President Bill Clinton seeking to terminate housing programs for people with AIDS.
Date: December 15, 1994
Creator: AIDS Services of Dallas
Object Type: Text
System: The UNT Digital Library
Monte Carlo Simulations of Phosphate Polyhedron Connectivity in Glasses (open access)

Monte Carlo Simulations of Phosphate Polyhedron Connectivity in Glasses

Monte Carlo simulations of phosphate tetrahedron connectivity distributions in alkali and alkaline earth phosphate glasses are reported. By utilizing a discrete bond model, the distribution of next-nearest neighbor connectivities between phosphate polyhedron for random, alternating and clustering bonding scenarios was evaluated as a function of the relative bond energy difference. The simulated distributions are compared to experimentally observed connectivities reported for solid-state two-dimensional exchange and double-quantum NMR experiments of phosphate glasses. These Monte Carlo simulations demonstrate that the polyhedron connectivity is best described by a random distribution in lithium phosphate and calcium phosphate glasses.
Date: December 21, 1999
Creator: ALAM,TODD M.
Object Type: Article
System: The UNT Digital Library
Classification of hydrostratigraphic units at the Savannah River Site, South Carolina (open access)

Classification of hydrostratigraphic units at the Savannah River Site, South Carolina

A detailed synthesis of the hydrologic, geophysical and core data from wells penetrating the updip Mesozoic-Cenozoic Coastal Plain sequence at and near the Savannah River Site (SRS) was conducted to define and classify the hydrostratigraphic units. The purpose of the study was to give the SRS a single unified hydrostratigraphic classification that defines and addresses the hydrogeologic characteristics of the aquifers underlying the site. The characterization, areal distribution and classification of the aquifer and aquifer systems gives SRS the tools to evaluate ground water movement and contaminant transport in a comprehensive regional context. An alpha-numeric nomenclature has been temporarily adopted in this report for classifying the aquifers and aquifer systems at SRS. Formal geographic names for the aquifers and aquifer systems will be proposed in the near future but must be agreed upon and ratified by the South Carolina Hydrostratigraphic Subcommittee which was in part organized for the purpose. The classification utilizes a hierarchy of terms ranked at three levels: Aquifer Systems that transmit ground water regionally; Aquifer Units which are mappable units > 400 square miles in area; and Aquifer Zones that differentiate aquifers internally on the basis of locally significant characteristics.
Date: December 1, 1990
Creator: Aadland, R. K. & Bledsoe, H. W.
Object Type: Report
System: The UNT Digital Library
Classification of hydrostratigraphic units at the Savannah River Site, South Carolina (open access)

Classification of hydrostratigraphic units at the Savannah River Site, South Carolina

A detailed synthesis of the hydrologic, geophysical and core data from wells penetrating the updip Mesozoic-Cenozoic Coastal Plain sequence at and near the Savannah River Site (SRS) was conducted to define and classify the hydrostratigraphic units. The purpose of the study was to give the SRS a single unified hydrostratigraphic classification that defines and addresses the hydrogeologic characteristics of the aquifers underlying the site. The characterization, areal distribution and classification of the aquifer and aquifer systems gives SRS the tools to evaluate ground water movement and contaminant transport in a comprehensive regional context. An alpha-numeric nomenclature has been temporarily adopted in this report for classifying the aquifers and aquifer systems at SRS. Formal geographic names for the aquifers and aquifer systems will be proposed in the near future but must be agreed upon and ratified by the South Carolina Hydrostratigraphic Subcommittee which was in part organized for the purpose. The classification utilizes a hierarchy of terms ranked at three levels: Aquifer Systems that transmit ground water regionally; Aquifer Units which are mappable units > 400 square miles in area; and Aquifer Zones that differentiate aquifers internally on the basis of locally significant characteristics.
Date: December 1, 1990
Creator: Aadland, R. K. & Bledsoe, H. W.
Object Type: Report
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
An engineering and economic evaluation of the methane de-NOX{sup SM} technology (open access)

An engineering and economic evaluation of the methane de-NOX{sup SM} technology

The Institute of Gas Technology (IGT) and Ogden Martin Systems, Inc. (OMS) are conducting joint engineering and economic evaluation of IGT`s METHANE de-NOX{sup SM} technology for its application to new, as well as retrofit, municipal waste combustors (MWCs). It is anticipated that this new technology offers a technically and economically attractive alternative to existing selective noncatalytic reduction (SNCR) systems for new facilities, as well as in retrofit applications. Consequently, IGT and OMS are considering pursuing a long-term demonstration of this technology on an OMS MWC. The METHANE de-NOX approach was developed based on extensive full-scale MWC infurnace characterization and pilot-scale testing using simulated combustion products. The approach involves injection of natural gas, together with recirculated flue gases (for mixing), above the grate to provide oxygen-deficient combustion conditions that promote the destruction of NO{sub x} precursors, as well as NO{sub x}. Extensive pilot-scale testing, using both simulated combustion products and actual municipal waste (MW), showed that significant NO{sub x} reduction could be achieved. The results were used to define the key operating parameters for a field evaluation of the process. A full-scale METHANE de-NOX system was designed and retrofitted to a 100-ton/day Riley/Takuma mass burn system at the Olmsted County Waste-to-Energy …
Date: December 31, 1993
Creator: Abbasi, H. A.; Khinkis, M. J. & Scherrer, R.
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
Sulfur removal in advanced two stage pressurized fluidized bed combustion. Technical report, March 1--May 31, 1995 (open access)

Sulfur removal in advanced two stage pressurized fluidized bed combustion. Technical report, March 1--May 31, 1995

The objective of this study is to obtain data on the rates and the extent of sulfation reactions involving partially sulfided calcium-based sorbents, and oxygen as well as sulfur dioxide, at operating conditions closely simulating those prevailing in the second stage (combustor) of Advanced Two-Stage Pressurized Fluidized-Bed Combustors. In these systems the CO{sub 2} partial pressure generally exceeds the equilibrium value for calcium carbonate decomposition. Therefore, calcium sulfate is produced through the reactions between SO{sub 2} and calcium carbonate as well as the reaction between calcium sulfide and oxygen. To achieve this objective, the rates of reaction involving SO{sub 2} and oxygen, calcium sulfide and calcium carbonate will be determined by conducting tests in a pressurized thermogravimetric analyzer unit. The sulfate tests conducted during this quarter, focused on the determination of the rate of sulfation reaction involving partially sulfided half-calcined dolomite and oxygen. The test parameters included CO{sub 2} and O{sub 2} concentrations, reaction temperature and pressure, as well as the sorbent particle size. The results obtained during this quarter suggest that the rate of sulfation reaction involving partially sulfided half-calcined dolomite and oxygen is very fast at temperatures above 850 C which rapidly increases with increasing temperature, achieving more …
Date: December 31, 1995
Creator: Abbasian, J.
Object Type: Report
System: The UNT Digital Library
Stabilization and/or regeneration of spent sorbents from coal gasification. Final technical report, September 1, 1991--August 31, 1992 (open access)

Stabilization and/or regeneration of spent sorbents from coal gasification. Final technical report, September 1, 1991--August 31, 1992

The objective of this investigation was 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 during the stabilization step. An additional objective of this study was to investigate the use of the Spent Sorbent Regeneration Process (SSRP) to regenerate spent Ca-based sorbent, 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 were reacted with oxygen and SO{sub 2} at various operating conditions and the extent of CaS and CaO conversion were determined. Partially sulfided dolomite was used in sulfidation/regeneration over several cycles and the regeneration efficiency and sorbent reactivity were determined after each cycle. The results of the stabilization tests show that partially sulfided Ca-based sorbents (both limestone and dolomite) can be sulfated at temperatures above 1500{degrees}F resulting in high CaS conversion without release of SO{sub 2} producing environmentally acceptable material for disposal in landfills. The results also indicate that spent dolomite can be regenerated in the SSRP process, in successive cycles, with high regeneration efficiency without loss …
Date: December 31, 1992
Creator: Abbasian, J.; Hill, A. H. & Wangerow, J. R.
Object Type: Report
System: The UNT Digital Library
Stabilization of spent sorbents from coal gasification. Final technical report, September 1, 1992--August 31, 1993 (open access)

Stabilization of spent sorbents from coal gasification. Final technical report, September 1, 1992--August 31, 1993

The objective of this investigation was to determine the rates of reactions involving partially sulfided dolomite and oxygen, which is needed for the design of the reactor system for the stabilization of sulfide-containing solid wastes from gasification of high sulfur coals. To achieve this objective, samples of partially sulfided dolomite were reacted with oxygen at a variety of operating conditions in a fluidized-bed reactor. The effect of external diffusion was eliminated by using small quantities of the sorbent and maintaining a high flow rate of the reactant gas. The reacted sorbents were analyzed to determine the extent of conversion as a function of operating variables including sorbent particle size, reaction temperature and pressure, and oxygen concentration. The results of sulfation tests indicate that the rate of reaction increases with increasing temperature, increasing oxygen partial pressure, and decreasing sorbent particle size. The rate of the sulfation reaction can be described by a diffuse interface model where both chemical reaction and intraparticle diffusion control the reaction rate. The kinetic model of the sulfation reaction was used to determine the requirements for the reactor system, i.e., reactor size and operating conditions, for successful stabilization of sulfide-containing solid wastes from gasification of high sulfur …
Date: December 31, 1993
Creator: Abbasian, J.; Hill, A. H.; Rue, D. M. & Wangerow, J. R.
Object Type: Report
System: The UNT Digital Library
Development of novel copper-based sorbents for hot-gas cleanup. Final technical report, September 1, 1991--August 31, 1992 (open access)

Development of novel copper-based sorbents for hot-gas cleanup. Final technical report, September 1, 1991--August 31, 1992

The objective of this investigation was 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. To achieve this objective, several novel binary oxides of copper were systematically evaluated and ranked in terms of their high-temperature stability against reduction to metal, sulfidation reactivity, and regenerability. The sorbents studied included oxides of chromium, cerium, aluminum, magnesium, manganese, titanium, iron, and silicon. The results of initial testing indicated that mixed binary oxides of copper with chromium (CuCr{sub 2}O{sub 4}) and cerium (CuO{circle_dot}CeO{sub 2}) were the most promising sorbents for such high temperature gas cleanup applications. These two sorbents were further evaluated in cyclic sulfidation/regeneration tests in 10--15 cycles to determine the effect of operating conditions on their performance. The results of this investigation indicate that the two selected sorbents, copper-chromium and copper-cerium, are capable of removing H{sub 2}S from the hot fuel gas to very low levels (<10 ppmv) at temperatures as high as 850{degree}C with good sorbent regenerability in cyclic process. These sorbents should be further studied to achieve optimum sorbent composition for hot gas cleanup application.
Date: December 31, 1992
Creator: Abbasian, J.; Hill, A. H.; Wangerow, J. R.; Flytzani-Stephanopoulos, M.; Bo, Luhong; Patel, C. et al.
Object Type: Report
System: The UNT Digital Library
Advanced Low-Temperature Fluid Bed Sorbents (open access)

Advanced Low-Temperature Fluid Bed Sorbents

This paper discusses the results obtained in an ongoing study geared towards developing advanced mixed-metal oxide sorbents for desulfurization of coal-derived fuel gases in the temperature range of 350 to 550{degrees}C. The paper focuses on the study related to the development of durable sorbents suitable for fluidized-bed application and addresses thermodynamic considerations, sulfidation kinetics, regenerability, and the physical and chemical characteristics of a number of novel sorbents.
Date: December 31, 1996
Creator: Abbasian, J.; Slimane, R. B. & Wangerow, J. R.
Object Type: Article
System: The UNT Digital Library
Development of regenerable copper-based sorbents for hot gas cleanup. Technical report, September 1, 1995--November 30, 1995 (open access)

Development of regenerable copper-based sorbents for hot gas cleanup. Technical report, September 1, 1995--November 30, 1995

The overall objective of this study is to determine the effectiveness of the copper-chromite sorbent (developed in previous ICCI-funded projects) for longer duration application under optimum conditions in the temperature range of 550{degrees}-650{degrees}C to minimize sorbent reduction and degradation during the cyclic process. To achieve this objective, several formulations of copper chromite sorbents are prepared. These sorbent formulations are screened for their desulfurization and regeneration capability at predetermined temperatures and gas residence times. The durability of the best sorbent formulation identified in the screening tests is evaluated in ``long-term`` durability tests conducted at the optimum operating conditions. This includes testing the sorbent in pellet and granular forms in packed- and fluidized-bed reactors. During this quarter, twenty one copper chromite-based sorbent formulations were prepared. Two sorbent formulations that have acceptable crush strength, designated as CuCr-10 and CuCr-21, were tested over 5 and 6 cycles respectively. The results indicate that both sorbents are reactive toward H{sub 2}S at 650{degrees}C and that the reactivity of the sorbents are relatively constant over the first 5 to 6 cycles. The H{sub 2}S prebreakthrough concentrations were generally about 20 to 30 ppm, making them suitable for IGCC application.
Date: December 31, 1995
Creator: Abbasian, J.; Slimane, R.B. & Hill, A.H.
Object Type: Report
System: The UNT Digital Library
Sulfur removal in advanced two stage pressurized fluidized bed combustion. Technical report, September 1--November 30, 1994 (open access)

Sulfur removal in advanced two stage pressurized fluidized bed combustion. Technical report, September 1--November 30, 1994

The objective of this study is to obtain data on the rates and the extent of sulfation reactions involving partially sulfided calcium-based sorbents, and oxygen as well as sulfur dioxide, at operating conditions closely simulating those prevailing in the second stage (combustor) of Advanced Two-Stage Pressurized Fluidized-Bed Combustors (PFBC). In these systems the CO{sub 2} partial pressure generally exceeds the equilibrium value for calcium carbonate decomposition. Therefore, calcium sulfate is produced through the reactions between SO{sub 2} and calcium carbonate as well as the reaction between calcium sulfide and oxygen. To achieve this objective, the rates of reaction involving SO{sub 2} and oxygen (gaseous reactant); and calcium sulfide and calcium carbonate (solid reactants), will be determined by conducting tests in a pressurized thermogravimetric analyzer (HPTGA) unit. The effects of sorbent type, sorbent particle size, reactor temperature and pressure; and O{sub 2} as well as SO{sub 2} partial pressures on the sulfation reactions rate will be determined. During this quarter, samples of the selected limestone and dolomite were sulfided in the fluidized-bed reactor. These tests were conducted in both calcining and non-calcining operating conditions to produce partially-sulfided sorbents containing calcium oxide and calcium carbonate, respectively. These samples which represent the carbonizer …
Date: December 31, 1994
Creator: Abbasian, Javad; Hill, Andy; Wangerow, James R. & Honea, Franklin I.
Object Type: Report
System: The UNT Digital Library
Culture and Anxiety: a Cross-Cultural Study (open access)

Culture and Anxiety: a Cross-Cultural Study

By measuring interactions among and between anxiety and the independent variables of country of origin, gender, level of education, and age, this study attempted to gain insight into how students from different countries experience anxiety on a U.S. college campus. Results of the Multivariate Analysis of Variance (MANOVA) and the univariate test(ANOVA) indicated that the gender and level of education of the subjects made no significant difference. However, when it came to country of origin, there were significant differences between two of the cultural groups and respective anxiety level. Findings also support a positive correlation between age and anxiety levels, with the youngest participants having the lowest anxiety levels.
Date: December 1998
Creator: Abbassi, Amir
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Stabilization of spent sorbents from coal-based power generation processes. Technical report, September 1, 1995--November 30,1995 (open access)

Stabilization of spent sorbents from coal-based power generation processes. Technical report, September 1, 1995--November 30,1995

The overall objective of this study is to determine the effect of implementation of the new and more stringent EPA Protocol Test Method involving sulfide containing waste, on the suitability of the oxidized spent sorbents from gasification of of high sulfur coals for disposal in landfills, and to determine the optimum operating conditions in a ``final`` hydrolysis stage for conversion of the residual calcium sulfide in these wastes to materials that are suitable for disposal in landfills. An additional objective is to study the effect of ash on the regeneration and ash-sorbent separation steps in the Spent Sorbent Regeneration Process (SSRP). To achieve these objectives, a large set of oxidized samples of sulfided calcium-based sorbents (produced in earlier ICCI-funded programs) as well as oxidized samples of gasifier discharge (containing ash and spent sorbent) are tested according to the new EPA test protocol. Samples of the oxidized spent sorbents that do not pass the EPA procedure are reacted with water and carbon dioxide to convert the residual calcium sulfide to calcium carbonate. During this quarter, samples of oxidized sulfided calcium-based sorbents, including untreated calcium sulfide-containing feed materials, were analyzed using both weak acid and more stringent strong acid tests. Preliminary analysis …
Date: December 31, 1995
Creator: Abbassian, J. & Hill, A.H.
Object Type: Report
System: The UNT Digital Library
First-Time Parenthood: Attachment, Family Variables, Emotional Reactions, and Task Responsibilities as Predictors Of Stress (open access)

First-Time Parenthood: Attachment, Family Variables, Emotional Reactions, and Task Responsibilities as Predictors Of Stress

The purpose of this study was to explore factors which are predictive of parenting stress for first-time parents. Based on attachment theory and empirical research, the factors investigated were the responsibility for child care and housework, the current and retrospective relationship with the family of origin, the change in emotions related to parenthood, the marital relationship, and attachment and individuation.
Date: December 1990
Creator: Abbott, Donna Christine
Object Type: Thesis or Dissertation
System: The UNT Digital Library
New technologies for item monitoring (open access)

New technologies for item monitoring

This report responds to the Department of Energy`s request that Sandia National Laboratories compare existing technologies against several advanced technologies as they apply to DOE needs to monitor the movement of material, weapons, or personnel for safety and security programs. The authors describe several material control systems, discuss their technologies, suggest possible applications, discuss assets and limitations, and project costs for each system. The following systems are described: WATCH system (Wireless Alarm Transmission of Container Handling); Tag system (an electrostatic proximity sensor); PANTRAK system (Personnel And Material Tracking); VRIS (Vault Remote Inventory System); VSIS (Vault Safety and Inventory System); AIMS (Authenticated Item Monitoring System); EIVS (Experimental Inventory Verification System); Metrox system (canister monitoring system); TCATS (Target Cueing And Tracking System); LGVSS (Light Grid Vault Surveillance System); CSS (Container Safeguards System); SAMMS (Security Alarm and Material Monitoring System); FOIDS (Fiber Optic Intelligence & Detection System); GRADS (Graded Radiation Detection System); and PINPAL (Physical Inventory Pallet).
Date: December 1, 1993
Creator: Abbott, J. A. & Waddoups, I. G.
Object Type: Report
System: The UNT Digital Library
An Analysis of Corporate Accounting and Reporting Practices in Bahrain (open access)

An Analysis of Corporate Accounting and Reporting Practices in Bahrain

The primary objective of this dissertation is to determine the factors that have shaped the corporate financial reporting practices in Bahrain. Prior researchers have offered two explanations, environmental factors and cultural importation, for the emergence of financial reporting practices in developing countries. The environmental explanation suggests that a nation's financial reporting practices will be shaped by its socioeconomic structure. The cultural importation explanation states that the desire for international legitimacy creates incentives for developing nation to adopt Western financial reporting practices. Bahrain provided an excellent environment in which to examine the two explanations since its public and closed corporations have similar economic characteristics. Only public corporations are legally required to publish financial reports. I posited that public corporations would try to gain legitimacy for their published reports by adopting Western standards, while closed corporations would not have a similar incentive. I used an interpretive framework to analyze the Bahrain socioeconomic environment and to examine the general financial reporting practices of Bahraini corporations. I found that closed corporations provided data responsive to the Bahraini environment. Public corporations, however, adopted International Accounting Standards. My analysis supported prior researchers7 findings that colonialism, the need for international legitimacy, and international audit firms were important …
Date: December 1993
Creator: Abdul-Rahim, Hassan M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Characterization of surfactants in the presence of oil for steam foam application (open access)

Characterization of surfactants in the presence of oil for steam foam application

The steam foam process has been applied in the oil fields since the late 1970`s. The mechanism of the process, however, is not known fully; particularly the detrimental effects of oil on foam, while known, are still unexplained. Understanding the mechanisms of foam generation, stability, and mobility of foam to improve the development of field level projects has been the focus of the attention of many workers of the oil industry. Extensive laboratory studies have been carried out, mostly without oil but some with oil. This study falls in the later category. A one dimensional sandpack (6 ft X 2.15 in) model is used to investigate the behavior of four anionic sulfonate surfactants of varying chemical structure with steam. The study is performed with an crude oil at residual oil saturation of about 12 percent of the pore volume. The observed pressure drops across the various sections of the pack are used to study the behavior of the surfactant. The tested surfactants vary in chain length, aromatic structure and number of ionic charges. A linear toluene sulfonate produced the highest strength foam in presence of the oil at residual saturations, as compared to the alpha olefin sulfonates. This is in …
Date: December 1, 1992
Creator: Abdul-Razzaq & Castanier, L. M.
Object Type: Report
System: The UNT Digital Library