Development of improved iron Fischer-Tropsch catalysts (open access)

Development of improved iron Fischer-Tropsch catalysts

The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.
Date: October 29, 1990
Creator: Bukur, D.B.
Object Type: Report
System: The UNT Digital Library
Magnetic field in the SSC arc quad (open access)

Magnetic field in the SSC arc quad

In part one we report on field calculations along the conductor in the end region of the SSC arc-quad. We have determined that the maximum field in the 2D section is 5.04 tesla located at the pole turn of the inner layer somewhere in the middle of the cable (strand 9)(fields are at 6500 A). At the end'' the maximum field is slightly higher 5.09 tesla located at the overpass (strand 11). The iron contribution was included assuming infinite permeability. In part two we include results of a 3D representation of the magnetic field inside the bore. The complete analysis, for which a brief description has been included here, is described elsewhere. This form for presenting the field is suitable for interfacing with other codes that make use of the 3D field components (particle tracking and stability). 69 figs.
Date: April 29, 1991
Creator: Caspi, S.; Helm, M. & Laslett, L.J.
Object Type: Report
System: The UNT Digital Library
Theoretical approach for enhanced mass transfer effects in-duct flue gas desulfurization processes (open access)

Theoretical approach for enhanced mass transfer effects in-duct flue gas desulfurization processes

Removal of sulfur dioxide (SO{sub 2}) from the flue gas of coal- burning power plants can be achieved by duct spray drying using calcium hydroxide (Ca(OH){sub 2}) slurries. A primary objective of this research was to discover the aspects of mass transfer into Ca(OH){sub 2} slurries which limit SO{sub 2} absorption. A bench- scale stirred tank reactor with a flat gas/liquid interface was used to simulate SO{sub 2} absorption in a slurry droplet. The absorption rate of SO{sub 2} from gas concentrations of 500 to 5000 ppm was measured at 55{degrees}C in clear solutions and slurries of Ca(OH){sub 2} up to 1.0 M (7 wt percent). Results are reported in terms of the enhancement factor, {O}. This research will allow prediction of conditions where the absorption of SO{sub 2} in Ca(OH){sub 2} slurries can be enhanced by changes to liquid phase constituents (under which SO{sub 2} absorption is controlled by liquid film mass transfer). Experiments in the stirred tank have shown that SO{sub 2} absorption in a 1.0 M Ca(OH){sub 2} slurry was completely dominated by gas film mass transfer with a large excess of Ca(OH){sub 2} but becomes controlled by liquid film resistance at greater than 50 percent Ca(OH){sub …
Date: January 29, 1992
Creator: Jozewicz, W. (Acurex Corp., Research Triangle Park, NC (United States). Environmental Systems Div.) & Rochelle, G.T. (Texas Univ., Austin, TX (United States). Dept. of Chemical Engineering)
Object Type: Report
System: The UNT Digital Library
SIMON Host Computer System requirements and recommendations (open access)

SIMON Host Computer System requirements and recommendations

Development Service Order {number sign}90025 requested recommendations for computer hardware, operating systems, and software development utilities based on current and future SIMON software requirements. Since SIMON's main objective is to be dispatched on missions by an operator with little computer experience, user friendly'' hardware and software interfaces are required. Other design criteria include: a fluid software development environment, and hardware and operating systems with minimal maintenance requirements. Also, the hardware should be expandable; extra processor boards should be easily integrated into the existing system. And finally, the use of well established standards for hardware and software should be implemented where practical.
Date: November 29, 1990
Creator: Harpring, L.J.
Object Type: Report
System: The UNT Digital Library
Theoretical approach for enhanced mass transfer effects in-duct flue gas desulfurization processes (open access)

Theoretical approach for enhanced mass transfer effects in-duct flue gas desulfurization processes

This report presents the results of fundamental mass transfer testing for in-duct removal of SO{sub 2}. Following this initial part of an experimental program, it became clear that the amount of initial moisture on the sorbent strongly affected the extent of Ca(OH){sub 2} conversion. Novel techniques aimed at increasing sorbent utilization were investigated and are described. Major novel technique investigated and reported on here was the reaction with SO{sub 2} of sorbents with initial free moisture (damp sorbents). The duct injection process using damp solids has the following steps: preparation of sorbent as a slurry, blending of the slurry with dry recycle materials to create damp solids, injection of the solids into the duct, reaction and drying of the solids with flue gas in the duct, collection in particulate control equipment, and finally recycle of dry solids with some bleed to disposal. The moisture content of the solids at each step affects system performance. Various factors favor high moisture whereas others favor low moisture. (VC)
Date: January 29, 1992
Creator: Jozewicz, W. (Acurex Corp., Research Triangle Park, NC (United States). Environmental Systems Div.) & Rochelle, G.T. (Texas Univ., Austin, TX (United States). Dept. of Chemical Engineering)
Object Type: Report
System: The UNT Digital Library
Full scale field test of the in situ air stripping process at the Savannah River integrated demonstration test site (open access)

Full scale field test of the in situ air stripping process at the Savannah River integrated demonstration test site

Under sponsorship from the US Department of Energy, technical personnel from the Savannah River Laboratory (SRL) and other DOE laboratories, universities and private industry have completed a full scale demonstration of environmental remediation using horizontal wells. This demonstration was performed as Phase I of an Integrated Demonstration Project designed to evaluate innovative remediation technologies for environmental restoration of sites contaminated with organic contaminants. The demonstration utilized two directionally drilled horizontal wells to deliver gases and extract contaminants from the subsurface. The resulting in situ air stripping process was designed to remediate soils and sediments above and below the water table as well as groundwater contaminated with volatile organic contaminants. The 139 day long test successfully removed volatile chlorinated solvents from the subsurface using the two horizontal wells. One well, approximately 300 ft (90m) long and 165 ft (50m) deep drilled below a contaminant plume in the groundwater, was used to inject air and strip the contaminants from the groundwater. A second horizontal well, approximately 175 ft (53m) long and 75 ft (23m) deep in the vadose zone, was used to extract residual contamination in the vadose zone along with the material purged from the groundwater. Pretest and posttest characterization data …
Date: June 29, 1991
Creator: Looney, B. B.; Hazen, T. C.; Kaback, D. S. & Eddy, C. A.
Object Type: Report
System: The UNT Digital Library
METEOROLOGICAL MONITORING PROGRAM, PARTICULATE MATTER AMBIENT AIR QUALITY MONITORING REPORT, JANUARY 1992 THROUGH DECEMBER 1995 (open access)

METEOROLOGICAL MONITORING PROGRAM, PARTICULATE MATTER AMBIENT AIR QUALITY MONITORING REPORT, JANUARY 1992 THROUGH DECEMBER 1995

None
Date: March 29, 1996
Creator: /a, n
Object Type: Report
System: The UNT Digital Library
The theory of High Energy Collision Processes (open access)

The theory of High Energy Collision Processes

This report briefly discusses research in proton-antiproton interactions and the standard model. (LSP)
Date: November 29, 1991
Creator: Wu, T. T.
Object Type: Report
System: The UNT Digital Library
Advanced design and modeling concepts for recombination x-ray lasers (open access)

Advanced design and modeling concepts for recombination x-ray lasers

Geometric, kinetic, and trapping issues, in short and ultrashort recombination x-ray lasers, are discussed. The design of a composite target consisting of a lasant strip on a plastic backing is described. Examples of modeling showing the effect of photon trapping and uncertainties in other physical processes on calculated gain coefficients are given. A simple and accurate expression for photon trapping in cylindrical geometry is presented. Recombination lasers that have the ground state as the lower laser state are shown to have small I{sub sat}'s and corresponding low efficiencies. Scaling laws for femtosecond laser-plasma interactions are presented. 19 refs.
Date: November 29, 1990
Creator: Eder, D.C.; Rosen, M.D.; Shephard, R.; Staffin, R.; Nash, J.K. & Keane, C.J.
Object Type: Article
System: The UNT Digital Library
Drilling operations at the Nevada Test Site (open access)

Drilling operations at the Nevada Test Site

The Nevada Operations Office (NV) is responsible for supporting the nuclear test programs of the Los Alamos and Lawrence Livermore National Laboratories. This support includes the drilling of test holes for nuclear device testing a the Nevada Test Site (NTS). The purpose of this audit was to assess the effectiveness of the Department of Energy's management of test hole inventories at the NTS. Our audit disclosed that NV accumulated a large inventory of unused test holes and approved drilling additional holes for which neither laboratory (Los Alamos nor Livermore) had identified a need. The overdrilling of test holes occurred because NV did not comply with good inventory practices that would have had NV's approving official question the need for, and the timing of, the laboratories' drilling requests. Instead, NV gave perfunctory approval to the laboratories' work orders for drilling test holes, and emphasized keeping two drill rig crews busy and satisfying the laboratories' demands for dedicated drilling personnel. Although NV did not agree that overdrilling had occurred, it has cut back its drilling activities and estimated that this will save abut $7.6 million annually. NV agreed with the recommendations in the report and has taken corrective actions.
Date: May 29, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Electric Power Monthly, August 1990. [Glossary included] (open access)

Electric Power Monthly, August 1990. [Glossary included]

The Electric Power Monthly (EPM) presents monthly summaries of electric utility statistics at the national, Census division, and State level. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. Data includes generation by energy source (coal, oil, gas, hydroelectric, and nuclear); generation by region; consumption of fossil fuels for power generation; sales of electric power, cost data; and unusual occurrences. A glossary is included.
Date: November 29, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Control of triacylglycerol biosynthesis in plants (open access)

Control of triacylglycerol biosynthesis in plants

Title list.
Date: January 29, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Computational simulations of plasma flow switches and imploding loads (open access)

Computational simulations of plasma flow switches and imploding loads

The Procyon system in the Los Alamos Trailmaster foil implosion project is intended to produce soft x-ray radiation by delivering about 1 MJ of kinetic energy to an imploding plasma liner. The final switching stage of this system will be a Plasma Flow Switch (PFS) which delivers current to the cylindrical foil load. 1-D and 2-D simulations are now being conducted to examine: the initiation of the PFS plasma: the dynamics of the PFS and its switching efficiency; the load implosion and resulting radiation output. Considered here, for the PFS and imploding load, are the effects of electrode walls, perturbations, and radiation. Comparisons with experiments (using the 1.5 MJ Pegasus capacitor bank) are also described. 5 refs., 6 figs.
Date: May 29, 1991
Creator: Peterson, D. L.; Bowers, R. L.; Brownell, J. H.; Greene, A. E. & Roderick, N. F.
Object Type: Article
System: The UNT Digital Library
Calculations of bottom quark production at hadron colliders (open access)

Calculations of bottom quark production at hadron colliders

This thesis studies Monte Carlo simulations of QCD heavy flavor production processes (p{bar p} {yields} Q({anti Q})X) at hadron colliders. ISAJET bottom quark cross-sections are compared to the O({alpha} {sub s}{sup 3}) perturbative calculation of Nason, Dawson, and Ellis. These Monte Carlo cross-sections are computed from data samples which use different parton distribution functions and physics parameters. Distributions are presented in the heavy quark's transverse momentum and rapidity. Correlations in rapidity and azimuthal angle are computed for the heavy flavor pair. Theory issues which arise are the behavior of the cross-section at low and high values of transverse momentum and the treatment of double counting problems in the flavor excitation samples. An important result is that ISAJET overestimates bottom quark production cross-sections and K factors. These findings are relevant for estimates of rates and backgrounds of heavy floor events.
Date: June 29, 1991
Creator: Kuebel, D.
Object Type: Report
System: The UNT Digital Library
Models of fragmentation phenomena based on the symmetric group S sub n and combinational analysis (open access)

Models of fragmentation phenomena based on the symmetric group S sub n and combinational analysis

Various models for fragmentation phenomena are developed using methods from permutation groups and combinational analysis. The appearance and properties of power laws in these models are discussed. Various exactly soluble cases are studied.
Date: January 29, 1991
Creator: Mekjian, A. Z. & Lee, S. J.
Object Type: Report
System: The UNT Digital Library
Corrosion fatigue of iron-chromium-nickel alloys: Fracture mechanics, microstructure and chemistry (open access)

Corrosion fatigue of iron-chromium-nickel alloys: Fracture mechanics, microstructure and chemistry

This progress report briefly summarizes the research performed under the referenced grant for the period from 1 December 1990 to 31 December 1991, and contains a cumulative listing of technical presentations and publications dating back to 1 June 1988. Under this grant, a multi-disciplinary research program is undertaken to address certain fundamental issues relating to corrosion fatigue crack growth in structurally important alloys in aqueous environments. The principal goal of the research is to develop and expand the scientific understanding of the processes that control corrosion fatigue crack growth, particularly for ferrous alloys in terms of the controlling mechanical and chemical/electrochemical processes and their interactions with the microstructure. Focus is placed upon the austenitic iron-chromium-nickel (FeCrNi) alloys because of the need to resolve certain mechanistic issues and because of extensive utilization of these alloys in the power generation and chemical industries. Emphasis is given to the growth of short (small) cracks at low growth rates because crack growth in this regime is expected to be more sensitive to changes in external chemical/electrochemical variables.
Date: January 29, 1992
Creator: Wei, Robert P.
Object Type: Report
System: The UNT Digital Library
Direct, experimental evidence of the Fermi surface in YBa sub 2 Cu sub 3 O sub 7-x (open access)

Direct, experimental evidence of the Fermi surface in YBa sub 2 Cu sub 3 O sub 7-x

We report new measurements of the electron-positron momentum spectra of YBa{sub 2}Cu{sub 3}O{sub 7-x} performed with ultra-high statistical precision. These data differ from previous results in two significant respects: They show the D{sub 2} symmetry appropriate for untwinned crystals and, more importantly, they show unmistakable, statistically significant, discontinuities that are evidence of a major Fermi surface section. These results provide a partial answer to a question of special significance to the study of high temperature superconductors i.e. the distribution of the electrons in the material, the electronic structure. Special consideration has been given both experimentally and theoretically to the existence and shape of a Fermi surface in the materials and to the superconducting gap. There are only three experimental techniques that can provide details of the electronic structure at useful resolutions. They are angular correlation of positron annihilation radiation, ACAR, angle resolved photo emission, PE, and de Haas van Alphen measurements. 11 refs., 4 figs.
Date: April 29, 1991
Creator: Haghighi, H.; Kaiser, J. H.; Rayner, S. L.; West, R. N.; Liu, J. Z.; Shelton, R. et al.
Object Type: Article
System: The UNT Digital Library
Final Report of Investigation of the Acoustic Decay Instability in Laser Plasma Interaction (open access)

Final Report of Investigation of the Acoustic Decay Instability in Laser Plasma Interaction

we have made extensive studies of the Ion Acoustic Decay Instability (IADI) in laser-produced plasmas using the Janus (Phoenix) laser at LLNL. We found that the threshold is quite low and that, in planar plasmas, it can be reduced to homogeneous-plasma, collisional values. These observations are consistent with the plasma-density profiles calculated by hydrodynamic simulations using the LASNEX computer code run with a flux limiter of f = 0.1. We have designed experiments to study the IADI in larger plasmas using the Nova laser. 2 refs., 1 fig.
Date: July 29, 1991
Creator: Young, P.; Drake, P.; Estabrook; Mizuno, K. & De Groot, J.S.
Object Type: Report
System: The UNT Digital Library
Pulsed laser kinetic studies of liquids under high pressure (open access)

Pulsed laser kinetic studies of liquids under high pressure

A high pressure apparatus has been constructed for measuring rates of reactions in liquids under pressures ranging from 1 atm to 2000 atm. This apparatus is being used to test the effect of ligand bulk on the rate of a thermal ring closure reaction. Microphonic photoacoustic signals obtained by illuminating solid samples with synchrotron soft x-rays and with visible laser beams have been successfully correlated with a theory for photoacoustic signal enhancement by volatile liquids. The concentration dependence of the fluorescence and nonradiative quantum yields for cresyl violet dissolved in methanol has been determined. Stability constants for complexes of lithium ion with four different crown ethers dissolved in a low temperature molten salt have been measured.
Date: November 29, 1990
Creator: Eyring, E.M.
Object Type: Report
System: The UNT Digital Library
Measurements of the total CO[sub 2] concentration and partial pressure of CO[sub 2] in seawater during WOCE expeditions in the South Pacific Ocean (open access)

Measurements of the total CO[sub 2] concentration and partial pressure of CO[sub 2] in seawater during WOCE expeditions in the South Pacific Ocean

During the first year of the grant, we participated in three WOCE expeditions (a total of 152 days at sea) in the South Pacific Ocean, and the field phase of the proposed investigation has been successfully completed. The total CO[sub 2] concentration and pCO[sub 2] were determined at sea in 4419 water samples collected at 422 stations. On the basis of the shipboard analyses of SIO Reference Solutions for CO, and a comparison with the results of previous expeditions, the overall precision of our total CO[sub 2] determinations is estimated to be about [plus minus]2 uM/kg. The deep water data indicate that there is a CO[sub 2] maximum centered about 2600 meters deep. This appears to represent a southward return flow from the North Pacific. The magnitude and distribution of the CO, maximum observed along the 135.0[degrees]W meridian differ from those observed along the 150.5[degrees]W meridian due to Tuamotu Archipelago, a topographic high which interferes with the southward return flow. The surface water pCO[sub 2] data indicate that the South Pacific sub-tropical gyre water located between about 15[degrees]S and 50[degrees]S is a sink for atmospheric CO[sub 2].
Date: June 29, 1993
Creator: Takahashi, T.; Goddard, J. G.; Chipman, D. W. & Rubin, S. I.
Object Type: Report
System: The UNT Digital Library
Savannah River Site computing architecture (open access)

Savannah River Site computing architecture

A computing architecture is a framework for making decisions about the implementation of computer technology and the supporting infrastructure. Because of the size, diversity, and amount of resources dedicated to computing at the Savannah River Site (SRS), there must be an overall strategic plan that can be followed by the thousands of site personnel who make decisions daily that directly affect the SRS computing environment and impact the site's production and business systems. This plan must address the following requirements: There must be SRS-wide standards for procurement or development of computing systems (hardware and software). The site computing organizations must develop systems that end users find easy to use. Systems must be put in place to support the primary function of site information workers. The developers of computer systems must be given tools that automate and speed up the development of information systems and applications based on computer technology. This document describes a proposal for a site-wide computing architecture that addresses the above requirements. In summary, this architecture is standards-based data-driven, and workstation-oriented with larger systems being utilized for the delivery of needed information to users in a client-server relationship.
Date: March 29, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Saturation and kinetic issues for optical-field-ionized plasma x-ray lasers (open access)

Saturation and kinetic issues for optical-field-ionized plasma x-ray lasers

Lasing between excited states and the ground state following optical-field ionization is studied. Saturation of an x-ray laser when the lower lasing level is a ground state of a H-like or Li-like ion is discussed. Efficiencies of 10{sup {minus}5} to 10{sup {minus}4} are calculated for the 3d{sub 5/2}--2p{sub 3/2} transition at 98 {Angstrom} in Li-like Ne. The assumption that the fine-structure levels are populated according to their statistical weights is shown to be justified through comparisons with calculations using a detailed atomic model. The effect of saturation by a given fine-structure transition on the populations of the fine-structure levels is analyzed. 4 refs., 2 figs.
Date: April 29, 1991
Creator: Eder, D.C.; Amendt, P.; Rosen, M.D.; Nash, J.K. & Wilks, S.C.
Object Type: Article
System: The UNT Digital Library
Corrosion Evaluation of Tank 40 Leak Detection Box (open access)

Corrosion Evaluation of Tank 40 Leak Detection Box

'Leak detection from the transfer lines in the tank farm has been a concern for many years because of the need to minimize exposure of personnel and contamination of the environment. The leak detection box (LDB) is one line of defense, which must be maintained to meet this objective. The evaluation of a failed LDB was one item from an action plan aimed at minimizing the degradation of LDBs. The Tank 40 LDB, which failed in service, was dug up and shipped to SRTC for evaluation. During a video inspection while in service, this LDB was found to have black tubercles on the interior, which suggested possible microbial involvement. The failure point, however, was believed to have occurred in the drain line from the transfer line jacket. Visual, metallurgical, and biological analyses were performed on the LDB. The analysis results showed that there was not any adverse microbiological growth or significant localized corrosion. The corrosion of the LDB was caused by exposure to aqueous environments and was typical of carbon steel pipes in soil environments.'
Date: July 29, 1999
Creator: Mickalonis, J.I.
Object Type: Report
System: The UNT Digital Library
Uniformity of material in the SME and MFT (open access)

Uniformity of material in the SME and MFT

The DWPF will satisfy the product consistency specification in the Waste Acceptance Preliminary Specifications through control of the chemical composition of the glass product. This control will be achieved by ensuring that each batch of feed in the Slurry Mix Evaporator (SME) will produce glass which satisfies the specification. The purpose of this report is to determine what degree of uniformity can be expected of material in the SME and Metter Feed Tank (MFT). These vessels were designed based on a design development process which had proven successful for similar hard-to-mix feeds in the past. This process resulted in a design of the SME and MFT agitation systems which was intended to provide highly uniform melter feed material. Based on the results of extensive tests in protoypic equipment, the SME and MFT designs have met this design goal.
Date: May 29, 1992
Creator: Plodinec, M.J.
Object Type: Report
System: The UNT Digital Library