Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite (open access)

Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

A cyclic voltammetry technique was used to study the interactions of pyrite during bioleaching with the bacterium Thiobacillus ferrooxidans. Potential effects of heavy metals (silver and mercury) and varying the pH on the iron oxidizing ability of the bacterium are reported. Redox potential techniques were used to study effect of ferrous sulfate concentration and pH on bacterial growth.
Date: January 20, 1993
Creator: Pesic, B.; Oliver, D. J.; Kim, Inbeum & De, G. C.
System: The UNT Digital Library
Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite. Final report (open access)

Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite. Final report

A cyclic voltammetry technique was used to study the interactions of pyrite during bioleaching with the bacterium Thiobacillus ferrooxidans. Potential effects of heavy metals (silver and mercury) and varying the pH on the iron oxidizing ability of the bacterium are reported. Redox potential techniques were used to study effect of ferrous sulfate concentration and pH on bacterial growth.
Date: January 20, 1993
Creator: Pesic, B.; Oliver, D. J.; Kim, Inbeum & De, G. C.
System: The UNT Digital Library
Engineering design and analysis of advanced physical fine coal cleaning technologies (open access)

Engineering design and analysis of advanced physical fine coal cleaning technologies

This project is sponsored by the United States Department of Energy (DOE) for the Engineering Design and Analysis of Advanced Physical Fine Coal Cleaning Technologies: The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This DOE project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies-heavy-liquid cycloning, selective agglomeration, and advanced froth flotation through the proof-of-concept (POC) level. The commercially available ASPEN PLUS process simulation package will be extended to handle coal cleaning applications. Algorithms for predicting the process performance, equipment size, and flowsheet economics of commercial coal cleaning devices and related ancillary equipment will be incorporated into the coal cleaning simulator. This report is submitted to document the progress of Aspen Technology, Inc. (AspenTech), its contractor, ICF Kaiser Engineers, Inc.,(ICF KE) and CQ Inc., a subcontractor to ICF KE, for the period of October through December 1992. ICF KE is providing coal preparation consulting and processing engineering services in this work and they are responsible for recommending the design of models to represent conventional coal cleaning equipment and costing of these models. CQ Inc. is a subcontractor …
Date: January 20, 1993
Creator: Gallier, P.W.
System: The UNT Digital Library
Engineering design and analysis of advanced physical fine coal cleaning technologies. Quarterly technical progress report No. 13, October--December 1992 (open access)

Engineering design and analysis of advanced physical fine coal cleaning technologies. Quarterly technical progress report No. 13, October--December 1992

This project is sponsored by the United States Department of Energy (DOE) for the ``Engineering Design and Analysis of Advanced Physical Fine Coal Cleaning Technologies: The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This DOE project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies-heavy-liquid cycloning, selective agglomeration, and advanced froth flotation through the proof-of-concept (POC) level. The commercially available ASPEN PLUS process simulation package will be extended to handle coal cleaning applications. Algorithms for predicting the process performance, equipment size, and flowsheet economics of commercial coal cleaning devices and related ancillary equipment will be incorporated into the coal cleaning simulator. This report is submitted to document the progress of Aspen Technology, Inc. (AspenTech), its contractor, ICF Kaiser Engineers, Inc.,(ICF KE) and CQ Inc., a subcontractor to ICF KE, for the period of October through December 1992. ICF KE is providing coal preparation consulting and processing engineering services in this work and they are responsible for recommending the design of models to represent conventional coal cleaning equipment and costing of these models. CQ Inc. is a subcontractor …
Date: January 20, 1993
Creator: Gallier, P. W.
System: The UNT Digital Library
Errors of DWPF frit analysis: Final report (open access)

Errors of DWPF frit analysis: Final report

Glass frit will be a major raw material for the operation of the Defense Waste Processing Facility. The frit will be controlled by certificate of conformance and a confirmatory analysis from a commercial analytical laboratory. The following effort provides additional quantitative information on the variability of frit chemical analyses at two commercial laboratories. Identical samples of IDMS Frit 202 were chemically analyzed at two commercial laboratories and at three different times over a period of four months. The SRL-ADS analyses, after correction with the reference standard and normalization, provided confirmatory information, but did not detect the low silica level in one of the frit samples. A methodology utilizing elliptical limits for confirming the certificate of conformance or confirmatory analysis was introduced and recommended for use when the analysis values are close but not within the specification limits. It was also suggested that the lithia specification limits might be reduced as long as CELS is used to confirm the analysis.
Date: January 20, 1993
Creator: Schumacher, R. F.
System: The UNT Digital Library
Errors of DWPF frit analysis: Final report. Revision 1 (open access)

Errors of DWPF frit analysis: Final report. Revision 1

Glass frit will be a major raw material for the operation of the Defense Waste Processing Facility. The frit will be controlled by certificate of conformance and a confirmatory analysis from a commercial analytical laboratory. The following effort provides additional quantitative information on the variability of frit chemical analyses at two commercial laboratories. Identical samples of IDMS Frit 202 were chemically analyzed at two commercial laboratories and at three different times over a period of four months. The SRL-ADS analyses, after correction with the reference standard and normalization, provided confirmatory information, but did not detect the low silica level in one of the frit samples. A methodology utilizing elliptical limits for confirming the certificate of conformance or confirmatory analysis was introduced and recommended for use when the analysis values are close but not within the specification limits. It was also suggested that the lithia specification limits might be reduced as long as CELS is used to confirm the analysis.
Date: January 20, 1993
Creator: Schumacher, R. F.
System: The UNT Digital Library
The {eta}{sub 6} at LEP and TRISTAN (open access)

The {eta}{sub 6} at LEP and TRISTAN

The {eta}{sub 6} is a {open_quotes}heavy axion{close_quotes} remnant of dynamical electroweak symmetry breaking by a color sextet quark condensate. Electroweak scale color instanton interactions allow it to be both very massive and yet be responsible for Strong CP conservation in the color triplet quark sector. It may have been seen at LEP via its two-photon decay mode and at TRISTAN via its hadronic decay modes.
Date: January 20, 1993
Creator: Kang, K.; Knowles, I. G. & White, A. R.
System: The UNT Digital Library
Fundamental mechanisms in flue gas conditioning (open access)

Fundamental mechanisms in flue gas conditioning

We performed a wide variety of laboratory analyses during the past quarter. As with most of the work we performed during the previous quarter, our recent efforts were primarily directed toward the determination of the effects of adsorbed water on the cohesivity and tensile strength of powders. We also continued our analyses of dust cake ashes that have had the soluble compounds leached from their particle surfaces by repeated washings with water. Our analyses of leached and unleached dust cake ashes continued to provide some interesting insights into effects that compounds adsorbed on surfaces of ash particles can have on bulk ash behavior. As suggested by our literature review, our data indicate that water adsorption depends on particle morphology and on surface chemistry. Our measurements of tensile strength show, that for many of the samples we have analyzed a relative minimum in tensile strength exists for samples conditioned and tested at about 30% relative humidity. In our examinations of the effects of water conditioning on sample cohesivity, we determined that in the absence of absorption of water into the interior of the particles, cohesivity usually increases sharply when environments having relative humidities above 75% are used to condition and test …
Date: January 20, 1993
Creator: Snyder, T. R. & Bush, P. V.
System: The UNT Digital Library
Fundamental mechanisms in flue gas conditioning. Quarterly report, October 1992--December 1992 (open access)

Fundamental mechanisms in flue gas conditioning. Quarterly report, October 1992--December 1992

We performed a wide variety of laboratory analyses during the past quarter. As with most of the work we performed during the previous quarter, our recent efforts were primarily directed toward the determination of the effects of adsorbed water on the cohesivity and tensile strength of powders. We also continued our analyses of dust cake ashes that have had the soluble compounds leached from their particle surfaces by repeated washings with water. Our analyses of leached and unleached dust cake ashes continued to provide some interesting insights into effects that compounds adsorbed on surfaces of ash particles can have on bulk ash behavior. As suggested by our literature review, our data indicate that water adsorption depends on particle morphology and on surface chemistry. Our measurements of tensile strength show, that for many of the samples we have analyzed a relative minimum in tensile strength exists for samples conditioned and tested at about 30% relative humidity. In our examinations of the effects of water conditioning on sample cohesivity, we determined that in the absence of absorption of water into the interior of the particles, cohesivity usually increases sharply when environments having relative humidities above 75% are used to condition and test …
Date: January 20, 1993
Creator: Snyder, T. R. & Bush, P. V.
System: The UNT Digital Library
Generalized energy principle for flute perturbations in axisymmetric mirror machines (open access)

Generalized energy principle for flute perturbations in axisymmetric mirror machines

Axial symmetry is a very desirable property of the mirror devices both for fusion and neutron source applications. The main obstacle to be circumvented in the development of such systems, is the flute instability of axisymmetric mirrors. In recent years there appeared a number of proposals, devoted to the stabilization of the flute perturbations in the framework of axisymmetric magnetic configurations, which are based on the combining of the MHD unstable central cell with various types of end-cell stabilizers. In the present paper we concentrate ourselves just on this scheme, including long solenoid with a uniform field, conjugated with the end stabilizing anchor, intended to provide MHD stability of the system as a whole. The attractive feature of such a configuration is that it allows to exploit finite larmor radius (FLR) effects for the stabilization of the flute perturbations. As is well known, FLR effects, being strong, stabilize all flute modes, except the one with azimuthal number m = 1, corresponding to the ``rigid`` displacement of the plasma column (the ``global`` mode). Consequently, in the conditions when FLR effects dominate, the anchor has to stabilize the ``global` mode only. Bearing in mind a favorable influence of FLR effects we, however, …
Date: January 20, 1993
Creator: Lansky, I. M. & Ryutov, D. D.
System: The UNT Digital Library
High SO[sub 2] removal efficiency testing (open access)

High SO[sub 2] removal efficiency testing

Baseline testing at the base'' site. Tampa Electric Company's (TECo's) Big Bend Station, commenced on September 28 and was completed on October 2. Initial results from this testing were presented in the previous Technical Progress Report, but a more complete discussion is provided in this report. Parametric testing was conducted at the Big Bend site during this quarter to evaluate the effects of dibasic acid (DBA) addition on system SQ removal performance. The parametric tests were conducted from November 2 through 19. A DBA consumption rate test was also conducted, after the parametric tests were completed. The DBA consumption test was conducted from November 21 through 25. Options I and II to the base program were exercised by DOE/PETC at the end of the previous quarter. These options involve testing at Hoosier Energy Rural Electric Cooperative Inc.'s Merom Station and Southwestern Electric Power Company's Pirkey Station, respectively. Testing was conducted at Merom Station during November. Previously, Radian Corporation was the test contractor for EPRI-funded performance additive testing at this site. This EPRI-funded testing involved the equivalent of baseline testing, parametric testing with both DBA and sodium formate performance additives, and an additive consumption test with the DBA additive. The results …
Date: January 20, 1993
Creator: Blythe, G.
System: The UNT Digital Library
High SO{sub 2} removal efficiency testing. Technical progress report, [October 1--December 31, 1992] (open access)

High SO{sub 2} removal efficiency testing. Technical progress report, [October 1--December 31, 1992]

Baseline testing at the ``base`` site. Tampa Electric Company`s (TECo`s) Big Bend Station, commenced on September 28 and was completed on October 2. Initial results from this testing were presented in the previous Technical Progress Report, but a more complete discussion is provided in this report. Parametric testing was conducted at the Big Bend site during this quarter to evaluate the effects of dibasic acid (DBA) addition on system SO{sub 2} removal performance. The parametric tests were conducted from November 2 through 19. A DBA consumption rate test was also conducted, after the parametric tests were completed. The DBA consumption test was conducted from November 21 through 25. Options I and II to the base program were exercised by DOE/PETC at the end of the previous quarter. These options involve testing at Hoosier Energy Rural Electric Cooperative Inc.`s Merom Station and Southwestern Electric Power Company`s Pirkey Station, respectively. Testing was conducted at Merom Station during November. Previously, Radian Corporation was the test contractor for EPRI-funded performance additive testing at this site. This EPRI-funded testing involved the equivalent of baseline testing, parametric testing with both DBA and sodium formate performance additives, and an additive consumption test with the DBA additive. The …
Date: January 20, 1993
Creator: Blythe, G.
System: The UNT Digital Library
Moored Instrument for Time Series Studies of Primary Production and Other Microbial Rate Processes (open access)

Moored Instrument for Time Series Studies of Primary Production and Other Microbial Rate Processes

The goal of this project is to build and test a Time Series Submersible Incubation Device (TS-SID) capable of the autonomous in situ measurement of phytoplankton production and other rate processes for a period of up at least three months. The instrument is conceptually based on a recently constructed Submersible Incubation Device (SID). The TS-SID is to possess the ability to periodically incubate samples in the presence of an appropriate tracer, and to store 94 chemically fixed subsamples for later analysis. The TS-SID has been designed to accurately simulate the natural environment, and to avoid trace metal contamination and physical damage to cells. Devices for biofouling control of internal and external surfaces are to be incorporated into the instrument. After the time series capabilities of the instrument have been successfully evaluated by medium-term coastal time series studies (up to one month), longer-term coastal time series studies (2-3 months) will be conducted to evaluate the biofouling prevention measures that have been used with the instrument.
Date: January 20, 1993
Creator: Taylor, C. D. & Doherty, K. W.
System: The UNT Digital Library
Moored Instrument for Time Series Studies of Primary Production and Other Microbial Rate Processes. Progress Report (open access)

Moored Instrument for Time Series Studies of Primary Production and Other Microbial Rate Processes. Progress Report

The goal of this project is to build and test a Time Series Submersible Incubation Device (TS-SID) capable of the autonomous in situ measurement of phytoplankton production and other rate processes for a period of up at least three months. The instrument is conceptually based on a recently constructed Submersible Incubation Device (SID). The TS-SID is to possess the ability to periodically incubate samples in the presence of an appropriate tracer, and to store 94 chemically fixed subsamples for later analysis. The TS-SID has been designed to accurately simulate the natural environment, and to avoid trace metal contamination and physical damage to cells. Devices for biofouling control of internal and external surfaces are to be incorporated into the instrument. After the time series capabilities of the instrument have been successfully evaluated by medium-term coastal time series studies (up to one month), longer-term coastal time series studies (2-3 months) will be conducted to evaluate the biofouling prevention measures that have been used with the instrument.
Date: January 20, 1993
Creator: Taylor, C. D. & Doherty, K. W.
System: The UNT Digital Library
Non-invasive measurements of granular flows by magnetic resonance imaging (open access)

Non-invasive measurements of granular flows by magnetic resonance imaging

Magnetic Resonance Imaging (MRI) was used to measure granular-flow in a partially filled, steadily rotating, long, horizontal cylinder. This non-invasive technique can yield statistically averaged two-dimensional concentrations and velocity profiles anywhere in the flow of suitable granular materials. First, rigid body motion of a cylinder fill with granular material was studied to confirm the validity of this method. Then, the density variation of the flowing layer where particles collide and dilate, and the depth of the flowing layer and the flow velocity profile were obtained as a function of the cylinder rotation rate.
Date: January 20, 1993
Creator: Nakagawa, M.; Altobelli, S. A.; Caprihan, A.; Fukushima, E. & Jeong, E. K.
System: The UNT Digital Library
Non-invasive measurements of granular flows by magnetic resonance imaging. Technical progress report for the quarter ending December 31, 1992 (open access)

Non-invasive measurements of granular flows by magnetic resonance imaging. Technical progress report for the quarter ending December 31, 1992

Magnetic Resonance Imaging (MRI) was used to measure granular-flow in a partially filled, steadily rotating, long, horizontal cylinder. This non-invasive technique can yield statistically averaged two-dimensional concentrations and velocity profiles anywhere in the flow of suitable granular materials. First, rigid body motion of a cylinder fill with granular material was studied to confirm the validity of this method. Then, the density variation of the flowing layer where particles collide and dilate, and the depth of the flowing layer and the flow velocity profile were obtained as a function of the cylinder rotation rate.
Date: January 20, 1993
Creator: Nakagawa, M.; Altobelli, S. A.; Caprihan, A.; Fukushima, E. & Jeong, E. K.
System: The UNT Digital Library
Surface electrochemical control for fine coal and pyrite separation. Final report (open access)

Surface electrochemical control for fine coal and pyrite separation. Final report

Laboratory flotation tests were carried out on three coals and on coal pyrite. Floatability measurements included natural floatability, flotation with a xanthate collector and salt flotation. The ranking of the floatability of the three coals were: Upper Freeport > Pittsburgh > Illinois. The floatability of mineral pyrite and coal pyrite increased markedly with xanthate concentration, but decreased with increased pH. In general, coal pyrite was more difficult to float than mineral pyrite. This was attributed to the presence of surface carbonaceous and mineral matter, since floatability of coal pyrite improved by acid pretreatment. Flotation tests demonstrated that the floatability of coal and mineral pyrite was greatly enhanced by the presence of an electrolyte. Flotation was also enhanced by the addition of modifiers such as CuSO{sub 4}, Na{sub 2}S, CO{sub 2} and EDTA. Lime additions markedly reduced the floatability of coal pyrite. Enhanced floatability of coal pyrite resulted when the pyrite was anodically oxidized in a specially constructed electrochemical flotation cell Pretreatment in potential ranges previously observed for polysulfide and sulfur film formation resulted in the enhanced floatability. While interesting trends and influences, both chemical and electrochemical, markedly improved the floatability of coal, there is little hope for reverse flotation as …
Date: January 20, 1993
Creator: Wadsworth, Milton E.; Bodily, David M.; Hu, Weibai; Chen, Wanxiong; Huang, Qinping; Liang, Jun et al.
System: The UNT Digital Library
Demonstration of an advanced circulation fludized bed coal combustor phase 1: Cold model study. Final report (open access)

Demonstration of an advanced circulation fludized bed coal combustor phase 1: Cold model study. Final report

It was found that there was a strong dependence of the density profile on the secondary air injection location and that there was a pronounced solid separation from the conveying gas, due to the swirl motion. Furthermore, the swirl motion generated strong internal circulation patterns and higher slip velocities than in the case of nonswirl motion as in an ordinary circulating fluidized bed. Radial solids flux profiles were measured at different axial locations. The general radial profile in a swirling circulating fluidized bed indicated an increased downward flow of solids near the bed walls, and strong variations in radial profiles along the axial height. For swirl numbers less than 0.9, which is typical for swirling circulating fluidized beds, there is no significant increase in erosion due to swirl motion inside the bed. Pending further investigation of swirl motion with combustion, at least from our cold model studies, no disadvantages due to the introduction of swirl motion were discovered.
Date: March 20, 1993
Creator: Govind, R.
System: The UNT Digital Library
Engineering design and analysis of advanced physical fine coal cleaning technologies (open access)

Engineering design and analysis of advanced physical fine coal cleaning technologies

Progress is identified in the following items reported as significant findings for the January 1993 reporting period: In Task 2, revisions to the dewatering topical report were started. In the Task 6 froth flotation work, Pittsburgh seam minus 28 mesh size and specific gravity analyses are complete, and analysis for the 100 mesh tests continued. Illinois No. 6 testing continues. In the Task 6 Coal Liberation work, ash analysis of 134 different composition/size fractions produced by the crushing of the 6M [times] 8M sample were completed.
Date: March 20, 1993
Creator: Gallier, P.W.
System: The UNT Digital Library
Engineering design and analysis of advanced physical fine coal cleaning technologies. Technical progress report No. 28 (open access)

Engineering design and analysis of advanced physical fine coal cleaning technologies. Technical progress report No. 28

Progress is identified in the following items reported as significant findings for the January 1993 reporting period: In Task 2, revisions to the dewatering topical report were started. In the Task 6 froth flotation work, Pittsburgh seam minus 28 mesh size and specific gravity analyses are complete, and analysis for the 100 mesh tests continued. Illinois No. 6 testing continues. In the Task 6 Coal Liberation work, ash analysis of 134 different composition/size fractions produced by the crushing of the 6M {times} 8M sample were completed.
Date: March 20, 1993
Creator: Gallier, P. W.
System: The UNT Digital Library
Enzymology and molecular biology of cell wall biosynthesis. Progress report (open access)

Enzymology and molecular biology of cell wall biosynthesis. Progress report

In order to be able to explore the control of cell wall polysaccharide synthesis at the molecular level, which inter alia might eventually lead to means for useful modification of plant biomass polysaccharide production, the immediate goals of this project are to identify polypeptides responsible for wall polysaccharide synthase activities and to obtain clones of the genes that encode them. We are concentrating on plasma membraneassociated (1,3)-{beta}-glucan synthase (glucan synthase-II or GS-II) and Golgi-associated (1,4)-{beta}-glucan synthase (glucan synthase-I or GS-I), of growing pea stem tissue. Our progress has been much more rapid with respect to GS-II than regarding GS-I.
Date: March 20, 1993
Creator: Ray, P. M.
System: The UNT Digital Library
Math and Science School (MASS): A Department of Energy enhancement program to benefit students from Native American Tribes affected by the Hanford Reservation (open access)

Math and Science School (MASS): A Department of Energy enhancement program to benefit students from Native American Tribes affected by the Hanford Reservation

Math and Science School is a program designed to enrich and encourage elementary students and teachers of the Confederated Tribes of the Umatilla Indian Reservation in the areas of mathematics and science activities. By providing access to special hands-on workshop sessions held in the mobile science laboratory at the school sites during the school year for students and teachers and with a separate summer inservice program for students, elementary children and teachers are encouraged to explore the fascination of science and the utility of mathematics through use of integrated curricula. The Department of Energy grant underwrites the instructional costs of this system while the grantee provides the mobile laboratory and the majority of the materials.
Date: March 20, 1993
Creator: Jaeger, M.
System: The UNT Digital Library
Math and Science School (MASS): A Department of Energy enhancement program to benefit students from Native American Tribes affected by the Hanford Reservation. Progress report (open access)

Math and Science School (MASS): A Department of Energy enhancement program to benefit students from Native American Tribes affected by the Hanford Reservation. Progress report

Math and Science School is a program designed to enrich and encourage elementary students and teachers of the Confederated Tribes of the Umatilla Indian Reservation in the areas of mathematics and science activities. By providing access to special hands-on workshop sessions held in the mobile science laboratory at the school sites during the school year for students and teachers and with a separate summer inservice program for students, elementary children and teachers are encouraged to explore the fascination of science and the utility of mathematics through use of integrated curricula. The Department of Energy grant underwrites the instructional costs of this system while the grantee provides the mobile laboratory and the majority of the materials.
Date: March 20, 1993
Creator: Jaeger, M.
System: The UNT Digital Library
Blind shaft drilling: The state of the art (open access)

Blind shaft drilling: The state of the art

This report discusses the ``Art`` of blind shaft drilling which has been in a continual state of evolution at the Nevada Test Site (NTS) since the start of underground testing in 1957. Emplacement holes for nuclear devices are still being drilled by the rotary drilling process, but almost all the hardware and systems have undergone many changes during the intervening years. Blind shaft drilling and tunnel construction technologies received increased emphasis with the signing of the LTBT in 1963.
Date: April 20, 1993
Creator: Rowe, P. A.
System: The UNT Digital Library