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The development of precipitated iron catalysts with improved stability (open access)

The development of precipitated iron catalysts with improved stability

The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr per gram iron (NL/hr/gFe) using a synthesis gas with 0.5-1.0 H{sub 2}:CO ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library
Site Specific Verification Guidelines. (open access)

Site Specific Verification Guidelines.

The Bonneville Power Administration (BPA) and the Northwest region have moved from energy surplus to a time when demand for energy is likely to exceed available supplies. The Northwest Power Planning Council is calling for a major push to acquire new resources.'' To meet anticipated loads in the next decade, BPA and the region must more than double that rate at which we acquire conservation resources. BPA hopes to achieve some of this doubling by programs independently designed and implemented by utilities and other parties without intensive BPA involvement. BPA will accept proposals for programs using performance-based payments, in which BPA bases its reimbursement to the sponsor on measured energy savings rather than program costs. To receive payment for conservation projects developed under performance-based programs, utilities and other project developers must propose verification plans to measure the amount of energy savings. BPA has traditionally used analysis of billing histories, before and after measure installation, adjusted by a comparison group on non-participating customers to measure conservation savings. This approach does not work well for all conversation projects. For large or unusual facilities the comparison group approach is not reliable due to the absence of enough comparable non-participants to allow appropriate statistical …
Date: May 1, 1992
Creator: Harding, Steve; Gordon, Frederick M. & Kennedy, Mike
System: The UNT Digital Library
Repair Welding of Fusion Reactor Components (open access)

Repair Welding of Fusion Reactor Components

Recent experimental investigations indicate that the repair welding of irradiated materials containing greater than 1 to 2.5 appm helium leads to catastrophic cracking in the heat affected zone of the weld. The high temperatures and cooling tensile stresses which occur during the welding process lead to enhanced helium bubble growth in the heat affected zone region, resulting in catastrophic cracking upon cooling. An investigation is proposed which seeks to determine the effect of stress state on the helium bubble growth process and develop engineering modifications to the welding process based upon this understanding in an attempt to alleviate or eliminate the weld cracking problem in type 316 stainless steel materials.
Date: May 20, 1992
Creator: Chin, Bryan A.
System: The UNT Digital Library
Milliwatt Generator Project (open access)

Milliwatt Generator Project

This report covers progress on the Milliwatt Generator Project from April 1986 through March 1988. Activities included fuel processing and characterization, production of heat sources, fabrication of pressure-burst test units, compatibility studies, impact testing, and examination of surveillance units. The major task of the Los Alamos Milliwatt Generator Project is to fabricate MC2893A heat sources (4.0 W) for MC2730A radioisotope thermoelectric generators (RTGS) and MC3599 heat sources (4.5 W) for MC3500 RTGs. The MWG Project interfaces with the following contractors: Sandia National Laboratories, Albuquerque (designer); E.I. du Pont de Nemours and Co. (Inc.), Savannah River Plant (fuel); Monsanto Research Corporation, Mound Facility (metal hardware); and General Electric Company, Neutron Devices Department (RTGs). In addition to MWG fabrication activities, Los Alamos is involved in (1) fabrication of pressure-burst test units, (2) compatibility testing and evaluation, (3) examination of surveillance units, and (4) impact testing and subsequent examination of compatibility and surveillance units.
Date: May 1, 1992
Creator: Latimer, T.W. & Rinehart, G.H.
System: The UNT Digital Library
Effects of catalytic mineral matter on CO/CO sub 2 , temperature and burning time for char combustion (open access)

Effects of catalytic mineral matter on CO/CO sub 2 , temperature and burning time for char combustion

The temperature of a char particle burning in an oxygen containing atmosphere is the product of a strongly coupled balance between particle size and physical properties, heat transfer from the particle, surface reactivity, CO/CO{sub 2} ratio and gas phase diffusion in the surrounding boundary layer and within the particle. CO{sub 2}/CO ratios can be strongly influenced by catalytic material in the carbon and by the char temperature. In this program we are measuring the CO{sub 2}/CO ratio for both catalyzed and uncatalyzed chars over a wide range of temperature. These results will then be used to develop predictive models for char temperature and burning rates. The electrodynamic balance has been successfully used to make such measurements for single 200{mu}m spherocarb particles. A few theoretical approaches to model a single particle oxidation have been made, but most of them assumed the infinitely thin reaction zone at the particle surface. This approach can not explain pore diffusion limitation, structural change, or reaction at low temperatures inside the particle. Too simplifying solid phase reaction may leads to wrong predictions. In this report, progress on constructing models including both solid and gas phase reaction are reported.
Date: May 4, 1992
Creator: Longwell, J. P.; Sarofim, A. F.; Lee, Chun-Hyuk & Modestino, A. J.
System: The UNT Digital Library
Manufactured Homes Acquisition Program : Heat Loss Assumptions and Calculations, Heat Loss Coefficient Tables. (open access)

Manufactured Homes Acquisition Program : Heat Loss Assumptions and Calculations, Heat Loss Coefficient Tables.

This manual is intended to assist builders of manufactured homes in assessing the thermal performance of structural components used in the Manufactured Housing Acquisition Program (MAP) sponsored by the Bonneville Power Administration (BPA). U-factors for these components are calculated using the ASHRAE (1989) parallel heat loss method, with adaptations made for the construction practices found in the Pacific Northwest manufactured home industry. This report is divided into two parts. The first part describes the general assumptions and calculation procedures used to develop U-factors and R-values for specific materials used in the construction industry, overall U-factors for component sections, and the impact of complex framing and thermal configurations on various components' heat loss rates. The individual components of manufactured homes are reviewed in terms of overall thermal conductivity. The second part contains tables showing the results of heat loss calculations expressed as U-factors for various configurations of the major building components: floor systems, ceiling systems, wall systems, windows, doors and skylights. These values can be used to establish compliance with the MAP specifications and thermal performance criteria or to compare manufactured homes built to different standards.
Date: May 1, 1992
Creator: Davis, Bob & Baylon, David
System: The UNT Digital Library
Surfaces and Thin Films Studied by Picosecond Ultrasonics (open access)

Surfaces and Thin Films Studied by Picosecond Ultrasonics

This research is the study of thin films and interfaces via the use of the picosecond ultrasonic technique. In these experiments ultrasonic waves are excited in a structure by means of a picosecond light pulse ( pump pulse''). The propagation of these waves is detected through the use of a probe light pulse that is time-delayed relative to the pump. This probe pulse measures the change {Delta}R(t) in the optical reflectivity of the structure that occurs because the ultrasonic wave changes the optical properties of the structure. This technique make possible the study of the attenuation and velocity of ultrasonic waves up to much higher frequencies than was previously possible (up to least 500 GHz). In addition, the excellent time-resolution of the method makes it possible to study nanostructures of linear dimensions down to 100 {Angstrom} or less by ultrasonic pulse-echo techniques. 25 refs.
Date: May 1, 1992
Creator: Maris, J. H. & Tauc, J.
System: The UNT Digital Library
Comparative mutagenesis of human cells in vivo and in vitro (open access)

Comparative mutagenesis of human cells in vivo and in vitro

This report discusses measuring methods of point mutations; high density cell cultures for low dose studies; measurement and sequence determination of mutations in DNA; the mutational spectra of styrene oxide and ethlyene oxide in TK-6 cells; mutational spectrum of Cr in human lymphoblast cells; mutational spectra of radon in TK-6 cells; and the mutational spectra of smokeless tobacco. (CBS)
Date: May 1, 1992
Creator: Thilly, W.G.
System: The UNT Digital Library
Fundamental spectroscopic studies of carbenes and hydrocarbon radicals (open access)

Fundamental spectroscopic studies of carbenes and hydrocarbon radicals

This document details activities during this reporting period topics discussed are: The first spectroscopic identification of the HCCCO and DCCCO radicals; detection of new vibrationally excited states of the carbon chain radicals CCH and CCD and the three-membered carbene ring, cyclopropenylidene; determination of an accurate structure of the cumulene carbene H{sub 2}CCC; analysis the hyperfine structure in the SiC radical; and the undertaking of a systematic search for new sulfur bearing radicals.
Date: May 1, 1992
Creator: Thaddeus, P. & Gottlieb, C.
System: The UNT Digital Library
International research into chlorofluorocarbon (CFC) alternatives (open access)

International research into chlorofluorocarbon (CFC) alternatives

Selected researchers from 21 countries were queried through questionnaires about their current and planned research activities. The results of the survey show that the majority of research being conducted by the respondents is devoted to investigating the hydrogenated fluorocarbon HFC-134a as a replacement for CFC-12 in refrigeration applications. The main issue with this alternative is identifying compatible lubricants that do not reduce its effectiveness.
Date: May 1, 1992
Creator: Marseille, T. J.; Shankle, D. L. & Thurman, A. G.
System: The UNT Digital Library
Research on elementary particle physics: Task P, Studies in theory and phenomenology of elementary particles (open access)

Research on elementary particle physics: Task P, Studies in theory and phenomenology of elementary particles

Over the last year, work has focused on two areas: the phenomenology of quark-gluon differentiation in jets, and theoretical studies involving Dirac-like equations for various systems. Substantive progress has been made in both areas. A paper comparing details of the Lund and Herwig simulations for quark and gluon jets has been written and accepted by Physical Review D. A paper describing a new type of Dirac equation for the relativistic harmonic oscillator, and finding solutions thereof, has been written and submitted for publication.
Date: May 1, 1992
Creator: unknown
System: The UNT Digital Library
Electrostatic turbulence and transport in the RFP edge (open access)

Electrostatic turbulence and transport in the RFP edge

This thesis details measurements of electrostatic turbulence and transport in the Madison Symmetric Torus reversed field pinch. The electrostatic fluctuation levels are found to be large, with {tilde n}{sub e}/n{sub e} {approximately} 30%--55% and {tilde T}{sub e}/T{sub e} {approximately} 15%--40%. The frequency and wavenumber spectra are broad, with {Delta}n {approximately} 70--150 and {Delta}m {approximately} 3--6, and differ from measured magnetic fluctuation spectra. The transport inferred from coherence measurements indicates that electrostatic fluctuations can account for most of the observed particle losses, but contribute only {approximately}20% to the observed electron energy loss.
Date: May 1, 1992
Creator: Spragins, C.W.
System: The UNT Digital Library
The structure of perturbative quantum gravity on a de Sitter background (open access)

The structure of perturbative quantum gravity on a de Sitter background

Classical gravitation on de Sitter space suffers from a linearization instability. One consequence is that the response to a spatially localized distribution of positive energy cannot be globally regular. We use this fact to show that no causal Green's function can give the correct linearized response to certain bilocalized distributions, even though these distributions obey the constraints of linearization stability. We avoid the problem by working on the open submanifold spanned by conformal coordinates. The retarded Green's function is first computed in a simple gauge, then the rest of the propagator is inferred by analyticity -- up to the usual ambiguity about real, analytic and homogeneous terms. We show that the latter can be chosen so as to give a propagator which does not grow in any direction. The ghost propagator is also given and the interaction vertices are worked out.
Date: May 1, 1992
Creator: Tsamis, N. C. & Woodward, R. P.
System: The UNT Digital Library
Theoretical Studies in Nuclear Reactions and Nuclear Structure (open access)

Theoretical Studies in Nuclear Reactions and Nuclear Structure

Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon's mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing …
Date: May 1, 1992
Creator: unknown
System: The UNT Digital Library
Weld Penetration and Defect Control (open access)

Weld Penetration and Defect Control

Highly engineered designs increasingly require the use of improved materials and sophisticated manufacturing techniques. To obtain optimal performance from these engineered products, improved weld properties and joint reliability are a necessarily. This requirement for improved weld performance and reliability has led to the development of high-performance welding systems in which pre-programmed parameters are specified before any welding takes place. These automated systems however lack the ability to compensate for perturbations which arise during the welding process. Hence the need for systems which monitor and control the in-process status of the welding process. This report discusses work carried out on weld penetration indicators and the feasibility of using these indicators for on-line penetration control.
Date: May 15, 1992
Creator: Chin, Bryan A.
System: The UNT Digital Library
Two dimensional NMR and NMR relaxation studies of coal structure (open access)

Two dimensional NMR and NMR relaxation studies of coal structure

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with {sup 13}C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed a delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.
Date: May 27, 1992
Creator: Zilm, K.W.
System: The UNT Digital Library
Vortices associated with toroidal ion temperature gradient driven fluctuations (open access)

Vortices associated with toroidal ion temperature gradient driven fluctuations

The three nonlinear hydrodynamic equations for potential, parallel ion velocity and ion pressure used in simulations of the toroidal ion temperature gradient driven fluctuations and transport in a shear magnetic field are analyzed for coherent vortex structures. Two types of vortex structures are found: one type for weak shear that is a generalization of the usual modon vortex construction and the second type of solution for strong magnetic shear where the convective nonlinearity in the parallel velocity field generates a cubic trapping nonlinearity in the vorticity equation. These vortex structures show the possibility of explaining the saturated states observed in the numerical simulations as self-organized nonlinear states in contrast to wave turbulence.
Date: May 1, 1992
Creator: Horton, W. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies); Jovanovic, D. (Belgrade Univ. (Yugoslavia). Inst. za Fiziku) & Rasmussen, J.J. (Association Euratom-Risoe National Lab., Roskilde (Denmark))
System: The UNT Digital Library
Assessment of the need for dual indoor/outdoor warning systems and enhanced tone alert technologies in the Chemical Stockpile Emergency Preparedness Program (open access)

Assessment of the need for dual indoor/outdoor warning systems and enhanced tone alert technologies in the Chemical Stockpile Emergency Preparedness Program

The need for a dual indoor/outdoor warning system as recommended by the program guidance and Alert and Notification (A N) standard for the Chemical Stockpile Emergency Preparedness Program is analyzed in this report. Under the current program standards, the outdoor warning system consists of omnidirectional sirens and the new indoor system would be an enhanced tone alert (TA) radio system. This analysis identifies various tone-alert technologies, distribution options, and alternative siren configurations. It also assesses the costs and benefits of the options and analyzes what appears to best meet program needs. Given the current evidence, it is recommended that a 10-dB siren system and the special or enhanced TA radio be distributed to each residence and special institution in the immediate response zone as preferred the A N standard. This approach minimizes the cost of maintenance and cost of the TA radio system while providing a high degree of reliability for indoor alerting. Furthermore, it reaches the population (residential and institutional) in the greatest need of indoor alerting.
Date: May 1, 1992
Creator: Sorensen, J.H.
System: The UNT Digital Library
Natural convection heat transfer analysis of ATR fuel elements (open access)

Natural convection heat transfer analysis of ATR fuel elements

Natural convection air cooling of the Advanced Test Reactor (ATR) fuel assemblies is analyzed to determine the level of decay heat that can be removed without exceeding the melting temperature of the fuel. The study was conducted to assist in the level 2 PRA analysis of a hypothetical ATR water canal draining accident. The heat transfer process is characterized by a very low Rayleigh number (Ra {approx} 10{sup {minus}5}) and a high temperature ratio. Since neither data nor analytical models were available for Ra < 0.1, an analytical approach is presented based upon the integral boundary layer equations. All assumptions and simplifications are presented and assessed and two models are developed from similar foundations. In one model, the well-known Boussinesq approximations are employed, the results from which are used to assess the modeling philosophy through comparison to existing data and published analytical results. In the other model, the Boussinesq approximations are not used, thus making the model more general and applicable to the ATR analysis.
Date: May 1, 1992
Creator: Langerman, M.A.
System: The UNT Digital Library
Broad-Application Test Reactor (open access)

Broad-Application Test Reactor

This report is about a new, safe, and operationally efficient DOE reactor of nuclear research and testing proposed for the early to mid- 21st Century. Dubbed the Broad-Application Test Reactor (BATR), the proposed facility incorporates a multiple-application, multiple-mission design to support DOE programs such as naval reactors and space power and propulsion, as well as research in medical, science, isotope, and electronics arenas. DOE research reactors are aging, and implementing major replacement projects requires long lead times. Primary design drivers include safety, low risk, minimum operation cost, mission flexibility, waste minimization, and long life. Scientists and engineers at the Idaho National Engineering Laboratory are evaluating possible fuel forms, structural materials, reactor geometries, coolants, and moderators.
Date: May 1, 1992
Creator: Motloch, C. G.
System: The UNT Digital Library
Comprehensive work plan and health and safety plan for the 7500 Area Contamination Site sampling at Oak Ridge National Laboratory, Oak Ridge, Tennessee (open access)

Comprehensive work plan and health and safety plan for the 7500 Area Contamination Site sampling at Oak Ridge National Laboratory, Oak Ridge, Tennessee

As part of the Environmental Restoration Program sponsored by the US Department of Energy's Office of Environmental Restoration and Waste Management, this plan has been developed for the environmental sampling efforts at the 7500 Area Contamination Site, Oak Ridge National Laboratory (ORNL), Oak Ridge, Tennessee. This plan was developed by the Measurement Applications and Development Group (MAD) of the Health and Safety Research Division of ORNL and will be implemented by ORNL/MAD. Major components of the plan include (1) a quality assurance project plan that describes the scope and objectives of ORNL/MAD activities at the 7500 Area Contamination Site, assigns responsibilities, and provides emergency information for contingencies that may arise during field operations; (2) sampling and analysis sections; (3) a site-specific health and safety section that describes general site hazards, hazards associated with specific tasks, personnel protection requirements, and mandatory safety procedures; (4) procedures and requirements for equipment decontamination and responsibilities for generated wastes, waste management, and contamination control; and (5) a discussion of form completion and reporting required to document activities at the 7500 Area Contamination Site.
Date: May 1, 1992
Creator: Burman, S. N.; Landguth, D. C.; Uziel, M. S.; Hatmaker, T. L. & Tiner, P. F.
System: The UNT Digital Library
Research in theoretical particle physics (open access)

Research in theoretical particle physics

This report discusses the following topics in high energy physics: dynamical symmetry breaking and Schwinger-Dyson equation; consistency bound on the minimal model Higgs mass; tests of physics beyond the standard model; particle astrophysics; the interface between perturbative and non-perturbative QCD; cosmology; anisotropy in quantum networks and integer quantum hall behavior; anomalous color transparency; quantum treatment of solitons; color transparency; quantum stabilization of skyrmions; and casimir effect. (LSP)
Date: May 1, 1992
Creator: McKay, D.W.; Munczek, H. & Ralston, J.
System: The UNT Digital Library
RF voltage modulation at discrete frequencies with applications to crystal channeling extraction (open access)

RF voltage modulation at discrete frequencies with applications to crystal channeling extraction

RF voltage modulation at a finite number of discrete frequencies is described in a Hamiltonian resonance framework. The theory is applied to the problem of parasitic extraction of a fixed target beam from a high energy proton collider, using a bent crystal as a thin septum'' within an effective width of about one micron. Three modes of employment of discrete resonances are proposed.First, a single relatively strong static drive'' resonance may be used to excite a test proton so that it will penetrate deeply into the channeling crystal. Second, a moderately strong feed'' resonance with a ramped modulation tune may be used to adiabatically trap protons near the edge of the beam core, and transport them to the drive resonance. Third, several weak resonances may be overlapped to create a chaotic amplitude band, either to transport protons to the drive resonance, or to provide a pulse stretching'' buffer between a feed resonance and the drive resonance. Extraction efficiency is semi- quantitatively described in terms of characteristic penetration,'' depletion,'' and repetition'' times. simulations are used to quantitatively confirm the fundamental results of the theory, and to show that a prototypical extraction scheme using all three modes promises good extraction performance.
Date: May 1, 1992
Creator: Gabella, W.; Rosenzweig, J. (California Univ., Los Angeles, CA (United States). Dept. of Physics); Kick, R. (Illinois Math and Science Academy, Aurora, Illinois (United States)) & Peggs, S. (Fermi National Accelerator Lab., Batavia, IL (United States))
System: The UNT Digital Library
The development of precipitated iron catalysts with improved stability (open access)

The development of precipitated iron catalysts with improved stability

The objective of this program is to identify the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and to use these chemical principles in the design of catalysts suitable for slurry reactors. The performance targets are 88% CO+H{sub 2} conversion with less than 1% deactivation/day for 1 month and a methane and ethane selectivity of no more than 7% (based on hydrocarbons and oxygenates only) at a space velocity of at least 2 normal liters per hr gram iron (NL/hr/gFe) using a synthesis gas with 0.5--1.0 H{sub 2}:Co ratio in a slurry reactor.
Date: May 6, 1992
Creator: Abrevaya, H.
System: The UNT Digital Library