Resource Type

A novel approach to highly dispersing catalytic materials in coal for gasification (open access)

A novel approach to highly dispersing catalytic materials in coal for gasification

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 catalysts for coal gasification. The work is focused on the elucidation of coal-catalyst precursor interactions in solution and the variables which control the adsorption and dispersion of coal gasification metal catalysts. In order to optimize coal-metal ion interactions and hence maximize catalyst activity, the study examines the surface electrochemistry of a lignite, subbituminous, and bituminous coals and their demineralized and oxidized derivatives prior to loading with the catalytic materials. The surface electrical properties of the coals are investigated with the aid of electrophoresis, while the effects of the surface charge on the co-adsorption of K{sup +} and Ca{sup 2+} are studied by agitating the coals with aqueous solutions of potassium and calcium. 8 refs., 6 figs.
Date: January 1, 1990
Creator: Abotsi, G.M.K. & Bota, K.B.
System: The UNT Digital Library
A novel approach to highly dispersing catalytic materials in coal for gasification (open access)

A novel approach to highly dispersing catalytic materials in coal for gasification

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 catalysts for coal gasification. The work is focused on the elucidation of coal-catalyst precursor interactions in solution and the variables which control the adsorption and dispersion of coal gasification metal catalysts. In order to optimize coal-metal ion interactions and hence maximize catalyst activity, the study examines the surface electrochemistry of a lignite, a subbituminous, and a bituminous coals and their demineralized and oxidized derivatives prior to loading with the catalytic materials. The surface electrical properties of the coals are investigated with the aid of electrophoresis, while the effects of the surface charge on the adsorption of K{sup +} and Ca{sup 2+} are studied by agitating the coals with aqueous solutions of potassium and calcium. Zeta potential studies show that the surfaces of the lignite are negatively charged between about pH2 to 11, the negative charge density increasing with increase in pH. Highly alkaline media promoted calcium adsorption due to high negative charge on the coal, while calcium uptake was inhibited in strongly acidic solutions.
Date: January 1, 1990
Creator: Abotsi, M.K. & Bota, K.B.
System: The UNT Digital Library
2DPUF: A sequential gaussian puff model (open access)

2DPUF: A sequential gaussian puff model

This report documents the Environmental Transport Section's (ETS) two-dimensional, sequential gaussian puff transport and dispersion model for emergency response. The sequential puff scheme is described, and the dispersion equations are presented. The advantages of this model over the ETS's PUFF/PLUME model are discussed. Options are calculating a two-dimensional wind field, interpolation procedures, and the wind field grid are described. The various grid systems for puff transport calculations and dose estimates are also described. A flow diagram for the modules comprising the 2DPUF code and a description of each module is presented.
Date: January 1, 1990
Creator: Addis, R.P. & O'Steen, B.L.
System: The UNT Digital Library
Investigation of ultrasonic wave interactions with fluid-saturated porous rocks (open access)

Investigation of ultrasonic wave interactions with fluid-saturated porous rocks

Investigation of ultrasonic waves, especially the slow compressional wave, with fluid-saturated porous solids, especially rocks. This research effort should fine applications in the geophysical evaluation of fluid-bearing porous rocks where parameters such as tortuosity, permeability, saturation level, and internal impurities are difficult to measure by conventional techniques. The proposed investigation may be divided into three major subtasks: Experimental study of surface wave propagation on fluid-saturated porous materials. A new, so-called direct excitation technique will be used on both air- and water-saturated samples; further development of the Lamb wave technique recently introduced to study guided wave propagation in thin fluid-saturated porous plates. The analytical treatment will be extended to account for viscous losses and scattering inhomogeneities; and theoretical and experimental study of slow wave propagation in fluid-saturated natural rocks. A new technique based on the transmission of airborne ultrasound through air-saturated porous plates will be used to determine properties such as tortuosity, permeability, etc. 22 refs., 37 figs., 3 tabs.
Date: January 1, 1990
Creator: Adler, L.
System: The UNT Digital Library
Novel reactor configuration for synthesis gas conversion to alcohols (open access)

Novel reactor configuration for synthesis gas conversion to alcohols

Research is ongoing to develop a reactor to convert synthesis gas to alcohol. Our objective during this quarter was to complete Task 2, calibration and automation of GC analysis protocols, and Task 3B, development of a dynamic response technique to determine the relevant parameters and of the algorithms for data acquisition and analysis for parameter estimation including the computer codes. In addition, we have started to work on Task 4, determination of the reaction kinetics in the CSTR we have designed. 3 figs., 1 tab.
Date: January 1, 1990
Creator: Akgerman, A. & Anthony, R. G.
System: The UNT Digital Library
Novel reactor configuration for synthesis gas conversion to alcohols (open access)

Novel reactor configuration for synthesis gas conversion to alcohols

Research continued on the design of a chemical reactor for synthesis gas conversion. During the second quarter our objective was to continue with Task 2 and start on Task 3. Task 2 involved standardization and automation of GC analysis protocols. Task 3, as stated in the work breakdown schedule, was the modification and automation of the trickle bed reactor and performing the initial factorial design experiments. We have decided to modify this task by expanding it to incorporate determination of the hydrodynamic and transport parameters of the trickle bed reactor in order to isolate and study just the reaction parameters. 1 fig.
Date: January 1, 1990
Creator: Akgerman, A. & Anthony, R. G.
System: The UNT Digital Library
Novel reactor configuration for synthesis gas conversion to alcohols (open access)

Novel reactor configuration for synthesis gas conversion to alcohols

Research continued on the conversion of synthesis gas to alcohols and reactor configuration. Our objective during this quarter was to complete Task IIIB, development of the algorithms for the dynamic response technique for parameter estimation; start Task IIIC, establishment of methodology for determination of the parameters of the trickle bed reactor in the microreactor assembly; and continue with Task IV, determination of the kinetics of the reaction in the slurry reactor. 3 figs.
Date: January 1, 1990
Creator: Akgerman, A. & Anthony, R. G.
System: The UNT Digital Library
A 1. 5--4 Kelvin detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogens fuels (open access)

A 1. 5--4 Kelvin detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogens fuels

A compact cold-transfer apparatus for engaging and retrieving samples at liquid helium temperatures (1.5--4K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target-shells containing highly spin-polarized deuterons in solid HD or D{sub 2} for inertially confined fusion (ICF) experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed. 9 refs., 6 figs.
Date: January 1, 1990
Creator: Alexander, N.; Barden, J.; Fan, Q. & Honig, A.
System: The UNT Digital Library
The coupling of thermochemistry and phase diagrams for group 3-5 semiconductor systems (open access)

The coupling of thermochemistry and phase diagrams for group 3-5 semiconductor systems

Progress in the first year of the renewal and fourth year of the program has primarily occurred in the experimental area and subsequent assessment of binary and ternary systems. Thermodynamic studies of the Al--In and Al--Sb systems have been carried out using solid electrolyte galvanic cells. Using the sensitive coulometric titration technique, aluminum activities were obtained for both systems. In addition, liquidus data were obtained for the Al--Sb system, and the Gibbs energy of formation of AlSb was determined. A detailed description of the work for the Al--In system is given in Appendix I while that for the Al--Sb system in Appendix II. For the Al--Sb system, the coulometric titration technique was also used to investigate, for the first time, the very narrow region of homogeneity in the Al--Sb compound. The experimental data obtained in this study were used along with the available literature data in the critical assessment and calculation of the Al--In and Al--Sb systems.
Date: January 1, 1990
Creator: Anderson, T. J.
System: The UNT Digital Library
ORNL '90 (open access)

ORNL '90

This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)
Date: January 1, 1990
Creator: Anderson, T.; Barnes, D. & Jefferson, J. (eds.)
System: The UNT Digital Library
CeCu sub 4 A ell and CeCu sub 2 Zn sub 2 A ell : Very heavy fermion systems in high magnetic fields (open access)

CeCu sub 4 A ell and CeCu sub 2 Zn sub 2 A ell : Very heavy fermion systems in high magnetic fields

CeCu{sub 4}A{ell} and CeCu{sub 2}Zn{sub 2}A{ell} are heavy fermion systems with extremely enhanced C/T (specific heat divided by temperature) values of 2.3 and 1.8 J/K{sup 2} respectively as T {yields} 0 K. The field dependence of the low temperature specific heat is also extreme; 11 T reduces C of CeCu{sub 4}A{ell} by more than a factor of five, 12.5 T suppresses C of CeCu{sub 2}Zn{sub 2}A{ell} about seven times. Magnetic field caused changes of the specific heat of CeCu{sub 4}A{ell} are consistent with a single ion Kondo model. Magnetic correlations are at least partially responsible for the enhanced low temperature specific heat of CeCu{sub 2}Zn{sub 2}A{ell}.
Date: January 1, 1990
Creator: Andraka, B.; Kim, J.S. (Florida Univ., Gainesville, FL (United States). Dept. of Physics); Stewart, G.R. (Florida Univ., Gainesville, FL (United States). Dept. of Physics Augsburg Univ. (Germany)) & Fisk, Z. (Los Alamos National Lab., NM (United States))
System: The UNT Digital Library
Experimental studies on group ignition of a cloud of coal particles (open access)

Experimental studies on group ignition of a cloud of coal particles

While the combustion characteristics of a single coal particle are well known, most practical applications of coal combustion involve a large number of particles burning collectively as a group. A group combustion model has been developed which models the transient combustion of a spherical coal cloud. This model predicts ignition of a homogeneous mixture of volatiles and oxygen outside the cloud. The flame then moves to the cloud surface, where it anchors itself until all of the oxygen at the cloud surface is consumed. Two concentric flames are then formed, an outward propagating diffusion flame and an inward propagating premixed/diffusion flame which supplies heat to the particles for pyrolysis. Once the inner flame has consumed all the oxygen in the cloud, pyrolysis is complete and the outer flame consumes the released volatiles. As the volatiles are consumed, the flame approaches the cloud surface. Once all the volatiles have been consumed, the remaining char in the cloud burns at rate controlled by the rate of oxygen diffusion to the cloud. 5 refs., 14 figs.
Date: January 1, 1990
Creator: Annamalai, K.
System: The UNT Digital Library
Future microprocessor farms: Offline and online (open access)

Future microprocessor farms: Offline and online

Microprocessor farms have been successfully employed in high energy physics for both offline analysis and online triggers. As the experiments continue to grow in size, so do the demands for processing power. The preliminary indications are that the large collider experiments will require at least a million VAX-11/780 equivalents of processing power for online trigger decisions and offline event reconstruction. This paper examines the current technology trends and projects the processing power that may be expected with the current farm architectures. 3 refs., 6 figs.
Date: January 12, 1990
Creator: Areti, H.
System: The UNT Digital Library
Mass storage for microprocessor farms (open access)

Mass storage for microprocessor farms

Experiments in high energy physics require high density and high speed mass storage. Mass storage is needed for data logging during the online data acquisition, data retrieval and storage during the event reconstruction and data manipulation during the physics analysis. This paper examines the storage and speed requirements at the first two stages of the experiments and suggests a possible starting point to deal with the problem. 3 refs., 3 figs.
Date: January 12, 1990
Creator: Areti, H.
System: The UNT Digital Library
[Catalytic Mechanism of Hydrogenase From Aerobic N Sub 2 -Fixing Microorganisms] (open access)

[Catalytic Mechanism of Hydrogenase From Aerobic N Sub 2 -Fixing Microorganisms]

Hydrogenases are enzymes which catalyze reactions involving dihydrogen. They serve integral roles in a number of microbial metabolic pathways. Our research is focussed on investigations of the catalytic mechanism of the hydrogenases found in aerobic, N{sub 2}-fixing microorganisms such as Azotobacter vinelandii and the agronomically important Bradyrhizobium japonicum as well as microorganisms with similar hydrogenases. The hydrogenases isolated from these microorganisms are Ni- and Fe-containing heterodimers. Our work has focussed on three areas during the last grant period. In all cases, a central theme has been the role of inhibitors in the characteristics under investigation. In addition, a number of collaborative efforts have yielded interesting results. In metalloenzymes such as hydrogenase, inhibitors often influence the activity of the enzyme through ligand interactions with redox centers, often metals, within the enzyme. Therefore, investigations of the ability of various compounds to inhibit an enzyme's activity, as well as the mechanism of inhibition, can provide insight into the catalytic mechanism of the enzyme as well as the role of various redox centers in catalysis. We have investigated in detail four inhibitors of A. vinelandii and the results are summarized here. The influence of these inhibitors on the spectral properties of the enzyme are …
Date: January 1, 1990
Creator: Arp, D. J.
System: The UNT Digital Library
Evaluation of Ground-Water Resources in Parts of Loving, Pecos, Reeves, Ward and Winkler Counties, Texas (open access)

Evaluation of Ground-Water Resources in Parts of Loving, Pecos, Reeves, Ward and Winkler Counties, Texas

From Purpose: "This study in the area of Loving, Pecos, Reeves, Ward, and Winkler Counties was conducted to address the problems of overdraft and quality deterioration with respect to the Cenozoic Pecos Alluvium aquifer (previously referred to as the Cenozoic Alluvium aquifer), which is the primary aquifer in the area. A discussion of underlying aquifers is also included" (p. 1).
Date: January 1990
Creator: Ashworth, John B.
System: The Portal to Texas History
Monochromosomal hybrids for the analysis of the human genome (open access)

Monochromosomal hybrids for the analysis of the human genome

In this research project the authors proposed to develop rodent/human hybrid cell lines each containing a single different human chromosome. The human chromosomes will be marked with Ecogpt and stably maintained by selection in the hybrid cells. The experimental approach to produce the proposed cell lines involve the following: they will first transfer a cloned selectable marker, Ecogpt (an E. coli gene for xanthine-guanine phosphoribosyltransferase: XGPRT) to normal diploid human cells using a retroviral vector. The transferred gene will integrate at random into multiple sites in the recipient cell genome. Clonal cell lines from independent transgenotes will each carry the selectable marker integrated into a different site and perhaps a different chromosome. The chromosome carrying the selectable marker will then be transferred further to mouse cells by microcell fusion. In addition they also use directed integration of Ecogpt into the chromosome present in rodent cells, otherwise not marked with a selectable marker. This allows them to complete the bank of proposed cell line. The human chromosome, since it will be marked with a selectable marker, can be transferred to any other cell line of interest for complementation analysis. Clones of each cell line, containing varying size segments of the same …
Date: January 1, 1990
Creator: Athwal, R. S.
System: The UNT Digital Library
(Comparison of group transfer, inner sphere and outer sphere electron transfer mechanisms of organometallic complexes) (open access)

(Comparison of group transfer, inner sphere and outer sphere electron transfer mechanisms of organometallic complexes)

During the course of Grant ER13775 we have constructed an infrared stopped-flow spectrophotometer and initiated a study of the mechanisms of reactions that involve a change in the oxidation state of organometallic complexes. The spectrometer combined conventional stopped-flow techniques with an infrared optical system comprised of a carbon monoxide laser, an IRTRAN flow-through cell and a mercury-cadium-telluride detector. In this summary we will highlight our results on reactions: (1) that formally involve exchange of a charged species between two metal carbonyl anions, (2) that involve additional of an electron to, or removal of an electron from organometallic complexes that contain a metal-metal bond, and (3) between coordination complexes and metal carbonyl anions. 12 refs.
Date: January 1, 1990
Creator: Atwood, J.
System: The UNT Digital Library
(Comparison of group transfer, inner sphere and outer sphere electron transfer mechanisms of organometallic complexes: Progress report) (open access)

(Comparison of group transfer, inner sphere and outer sphere electron transfer mechanisms of organometallic complexes: Progress report)

We have constructed an infrared stopped-flow spectrophotometer and initiated a study of the mechanisms of reactions that involve a change in the oxidation state of organometallic complexes. In this summary we highlight our results on reactions (1) that formally involve exchange of a charged species between two metal carbonyl anions, (2) that involve addition of an electron to, or removal of an electron from organometallic complexes that contain a metal-metal bond, and (3) between coordination complexes and metal carbonyl anions.
Date: January 1, 1990
Creator: Atwood, J.
System: The UNT Digital Library
The Supersymmetric Generalized Modified KdV Hierarchy and Odd Minimal Superconformal Field Theories Coupled to 2D Supergravity: 2 (open access)

The Supersymmetric Generalized Modified KdV Hierarchy and Odd Minimal Superconformal Field Theories Coupled to 2D Supergravity: 2

We further study the universal equations of the supersymmetric modified KdV (MKdV) hierarchy in its generalized form. We show that these equations describe the dynamical quantum equations of the odd series of N = 1 minimal (p,q) superconformal field theory coupled to N = 1 supergravity in particular those unitary series with p = 2k + 3, and q = 2k = 1. The string susceptibility of these models is {gamma}{sub sstr.}{sup (0)} = {minus}2/2k + 1. We demonstrate explicitly the cases k = 2; and k = 3. 10 refs.
Date: January 1, 1990
Creator: Awada, M.A.
System: The UNT Digital Library
South Fork Clearwater River Habitat Enhancement, Crooked and Red Rivers : Annual Report, 1989. (open access)

South Fork Clearwater River Habitat Enhancement, Crooked and Red Rivers : Annual Report, 1989.

In 1983, the Nez Perce National Forest and the Bonneville Power Administration entered into an interagency agreement to enhance and improve habitat for two anadromous fish species, spring chinook salmon (Oncorhynchus tshawyscha) and summer steelhead trout (Onchorhyncus mykiss), in the South Fork Clearwater River tributaries. The South Fork Clearwater River was dammed in 1927 for hydroelectric development. Anadromous fish runs were virtually eliminated until the dam was removed in 1962. To complicate the problem, upstream spawning and rearing habitats were severely impacted by dredge and hydraulic mining, road building, timber harvest, and over-grazing. Fish habitat improvement projects under the above contract are being carried out in two major tributaries to the South Fork Clearwater River. Both the Red River and the Crooked River projects began in 1983 and will be completed in 1990. 12 figures., 1 tab.
Date: January 1, 1990
Creator: Baer, William H.
System: The UNT Digital Library
Umatilla Basin Habitat Improvement Project. (open access)

Umatilla Basin Habitat Improvement Project.

This annual report is in fulfillment of contract obligations with Bonneville Power Administration which is the funding source for the Oregon Department of Fish and Wildlife's Umatilla Basin Habitat Improvement Project. The major activities undertaken during this report period were: procurement of 17 cooperative lease agreements with private landowners, design and layout of 8.6 miles of riparian exclosure fence and 3.0 miles of instream structures, development of five fencing contracts and six instream work contracts. Results include implementation of 10 miles of fencing and 3 miles of instream work. Other activities undertaken during this report period are: data collection from 90 habitat monitoring transects, collection and summarization of temperature data, photopoint establishment, coordination with numerous agencies and tribes and education of all age groups on habitat improvement and protection. 4 refs., 4 figs., 6 tabs.
Date: January 1, 1990
Creator: Bailey, Timothy D.
System: The UNT Digital Library
Evaluation of Water Resources in Part of Central Texas (open access)

Evaluation of Water Resources in Part of Central Texas

Report studying the central Texas region's water resources, with notes that there has been rapid decline and contamination in the area. The aquifer is also being used faster than it can naturally replenish.
Date: January 1990
Creator: Baker, Bernard; Duffin, Gail; Flores, Robert & Lynch, Tad
System: The Portal to Texas History
Adirondack Lakes Survey: An Interpretive Analysis of Fish Communities and Water Chemistry, 1984--1987 (open access)

Adirondack Lakes Survey: An Interpretive Analysis of Fish Communities and Water Chemistry, 1984--1987

The Adirondack Lakes Survey Corporation (ALSC) was formed as a cooperative effort of the New York State Department of Environmental Conservation and the Empire State Electric Energy Research Corporation to better characterize the chemical and biological status of Adirondack lakes. Between 1984 and 1987, the ALSC surveyed 1469 lakes within the Adirondack ecological zone. As a follow-up to the survey, the ALSC sponsored a series of interpretive analyses of the ALSC data base. The primary objectives of these analyses were as follows: Evaluate the influence of mineral acids (from acidic deposition) and nonmineral acids (natural organic acids) on lake pH levels; classify Adirondack lakes according to lake and watershed features expected to influence their responsiveness to changes in acidic deposition; evaluate the sensitivity of Adirondack lakes to changes in environmental conditions, such as changes in mineral acids or dissolved organic carbon concentrations; identify lake characteristics important in explaining the observed present-day status of fish communities in Adirondack lakes, in particular the relative importance of lake acidity; evaluate changes that have occurred over time in Adirondack fish communities and probable causes for these trends by using the available historical data on fish communities in the Adirondacks and the ALSC data base; …
Date: January 1, 1990
Creator: Baker, Joan P.; Gherini, S. A.; Munson, R. K.; Christensen, S. W.; Driscoll, C. T.; Gallagher, J. et al.
System: The UNT Digital Library