Serial/Series Title
Development of Continuous Solvent Extraction Processes for Coal Derived Carbon Products Quarterly Report
3
Winter Fuels Report
3
Irradiation Processing Department Monthly Report
2
Monthly Highlights for Office of Nuclear Regulatory Research Programs at Oak Ridge National Laboratory
2
Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipline Leak Detection Progress Report
1
Determination of Basalt Physical and Thermal Properties at Varying Temperatures, Pressures, and Moisture Contents Progress Report
1
Dimensional Effects in Controlled Structure Supported Catalysts Derived From Layered Synthetic Microstructures Progress Report
1
Fiscal Year 1979
1
Fiscal Year 1997
1
Fiscal Year 1998
1
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Detection of Depleted Uranium in Soil Using Portable Hand-Held Instruments
The Measurement Applications and Development Group at the Oak Ridge National Laboratory (ORNL) has collected and analyzed data with the purpose of evaluating the in-situ detection capabilities of common hand-held detectors for depleted uranium ({sup 238}U) in soil. Measurements were collected with one each of the following detectors: a FIDLER operated in a gross (full spectrum) mode, a FIDLER operated in a spectrum specific (windowed) mode, a 1.25'' x 1.5'' cylindrical NaI detector operated with a gross count rate system, and both open and closed-window pancake-type detectors. Representative samples were then collected at the same location and later analyzed at an ORNL laboratory. This report presents a correlation between the measurements and the soil concentration results and should be helpful to anyone interested in estimating measurement sensitivities for depleted uranium in soil.
Date:
November 13, 1999
Creator:
Coleman, R.L.
Object Type:
Article
System:
The UNT Digital Library
Two implementations of shared virtual space environments.
While many issues in the area of virtual reality (VR) research have been addressed in recent years, the constant leaps forward in technology continue to push the field forward. VR research no longer is focused only on computer graphics, but instead has become even more interdisciplinary, combining the fields of networking, distributed computing, and even artificial intelligence. In this article we discuss some of the issues associated with distributed, collaborative virtual reality, as well as lessons learned during the development of two distributed virtual reality applications.
Date:
January 13, 1998
Creator:
Disz, T. L.
Object Type:
Article
System:
The UNT Digital Library
Modeling the post-yield flow behavior after neutron and electron irradiation of steels and iron-base alloys.
Irradiation hardening is an issue of practical importance as it relates to the remanent life and the nature of failure of reactor components exposed to displacement-producing radiation. For example, irradiation-induced yield strength increases in pressure vessel steels are directly related to increases in the ductile-to-brittle-transition-temperature of these materials. Other issues associated with hardening, such as reductions in ductility, toughness and fatigue life of structural steels are also of concern. Understanding these phenomena requires studies of fundamental microstructural mechanisms of hardening. Because of the limited supply of neutron-irradiated surveillance material, difficulties posed by the radioactivity of neutron-exposed samples and the uncertainty of irradiation conditions in this case, fundamental studies are often conducted using well-controlled experiments involving irradiation by electrons instead of neutrons. Also, in such studies, simple model alloys are used in place of steels to focus on the influence of specific alloy constituents. It is, therefore, important to understand the relationship between the results of this kind of experiment and the effects of in-reactor neutron exposure in order to use them to make predictions of significance to reactor component life. In this paper, we analyze the tensile behavior of pressure vessel steels (A212B and A350) irradiated by neutrons and electrons. …
Date:
January 13, 1999
Creator:
Dimelfi, R. J.
Object Type:
Article
System:
The UNT Digital Library
Preparation of multilayered materials in cross-section for in situ TEM tensile deformation studies
The success of in-situ transmission electron microscopy experimentation is often dictated by proper specimen preparation. We report here a novel technique permitting the production of cross-sectioned tensile specimens of multilayered films for in-situ deformation studies. Of primary importance in the development of this technique is the production of an electron transparent micro-gauge section using focused ion beam technology. This microgauge section predetermines the position at which plastic deformation is initiated; crack nucleation, growth and failure are then subsequently observed.
Date:
May 13, 1997
Creator:
Wall, M. A.
Object Type:
Article
System:
The UNT Digital Library
Statement of capabilities: Micropower Impulse Radar (MIR) technology applied to mine detection and imaging
The Lawrence Livermore National Laboratory (LLNL) has developed radar and imaging technologies with potential applications in mine detection by the armed forces and other agencies involved in demining efforts. These new technologies use a patented ultra-wideband (impulse) radar technology that is compact, low-cost, and low power. Designated as Micropower Impulse Radar, these compact, self-contained radars can easily be assembled into arrays to form complete ground penetrating radar imaging systems. LLNL has also developed tomographic reconstruction and signal processing software capable of producing high-resolution 2-D and 3-D images of objects buried in materials like soil or concrete from radar data. Preliminary test results have shown that a radar imaging system using these technologies has the ability to image both metallic and plastic land mine surrogate targets buried in 5 to 10 cm of moist soil. In dry soil, the system can detect buried objects to a depth of 30 cm and more. This report describes LLNL`s unique capabilities and technologies that can be applied to the demining problem.
Date:
March 13, 1995
Creator:
Azevedo, S. G.; Gavel, D. T.; Mast, J. E. & Warhus, J. P.
Object Type:
Report
System:
The UNT Digital Library
HIGH RESOLUTION PHOTOEMISSION STUDIES OF COMPLEX MATERIALS.
Recent instrumentation developments in photoemission are providing new insights into the physics of complex materials. With increased energy and momentum resolution, it has become possible to examine in detail different contributions to the self-energy or inverse lifetime of the photohole created in the photoexcitation process, Employing momentum distribution and energy distribution curves, a detailed study of the optimally doped cuprate, Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub g+{delta}}, shows that the material behaves like a non-Fermi liquid with no evidence for the quasi-particles characteristic of a Fermi liquid.
Date:
October 13, 1999
Creator:
JOHNSON,P.D.
Object Type:
Article
System:
The UNT Digital Library
A microkernel design for component-based parallel numerical software systems.
What is the minimal software infrastructure and what type of conventions are needed to simplify development of sophisticated parallel numerical application codes using a variety of software components that are not necessarily available as source code? We propose an opaque object-based model where the objects are dynamically loadable from the file system or network. The microkernel required to manage such a system needs to include, at most: (1) a few basic services, namely--a mechanism for loading objects at run time via dynamic link libraries, and consistent schemes for error handling and memory management; and (2) selected methods that all objects share, to deal with object life (destruction, reference counting, relationships), and object observation (viewing, profiling, tracing). We are experimenting with these ideas in the context of extensible numerical software within the ALICE (Advanced Large-scale Integrated Computational Environment) project, where we are building the microkernel to manage the interoperability among various tools for large-scale scientific simulations. This paper presents some preliminary observations and conclusions from our work with microkernel design.
Date:
January 13, 1999
Creator:
Balay, S.
Object Type:
Article
System:
The UNT Digital Library
Photocatalytic and Chemical Oxidation of Organic Compounds in Supercritical Carbon Dioxide
Determine if photocatalytic or other clean oxidation chemistry can be applied to the removal of organic or inorganic contaminants that are introduced into supercritical carbon dioxide during its use as an extraction and cleaning medium in DOE environmental and waste minimization applications. The targets are those contaminants left in solution after the bulk of the solutes have been separated from the fluid phase by changing pressure and/or temperature (but not evaporating the CO2). This is applicable to development of efficient separations of contaminants from the fluid stream and will strengthen pollution prevention strategies that eliminate hazardous solvents and cleaning agents. Explore the use of supercritical carbon dioxide as a solvent for the photocatalytic oxidation of organic compounds and compare it to other types of oxidation chemistry. This will add to the fundamental understanding of photocatalytic oxidation chemistry of particulate semiconductors and provide new knowledge about conditions that may have relevance to the chemical fixation of carbon dioxide under photocatalytic conditions.
Date:
July 13, 1999
Creator:
Blake, D. M.
Object Type:
Report
System:
The UNT Digital Library
Model-Based Engineering and Manufacturing CAD/CAM Benchmark.
The Benchmark Project was created from a desire to identify best practices and improve the overall efficiency and performance of the Y-12 Plant's systems and personnel supporting the manufacturing mission. The mission of the benchmark team was to search out industry leaders in manufacturing and evaluate their engineering practices and processes to determine direction and focus for Y-12 modernization efforts. The companies visited included several large established companies and a new, small, high-tech machining firm. As a result of this effort, changes are recommended that will enable Y-12 to become a more modern, responsive, cost-effective manufacturing facility capable of supporting the needs of the Nuclear Weapons Complex (NWC) into the 21st century. The benchmark team identified key areas of interest, both focused and general. The focus areas included Human Resources, Information Management, Manufacturing Software Tools, and Standards/Policies and Practices. Areas of general interest included Infrastructure, Computer Platforms and Networking, and Organizational Structure. The results of this benchmark showed that all companies are moving in the direction of model-based engineering and manufacturing. There was evidence that many companies are trying to grasp how to manage current and legacy data. In terms of engineering design software tools, the companies contacted were somewhere …
Date:
October 13, 1999
Creator:
Domm, T.C. & Underwood, R.S.
Object Type:
Report
System:
The UNT Digital Library
Optimization of Ultrasonic Fabric Cleaning
The fundamental purpose of this project was to research and develop a process that would reduce the cost and improve the environmental efficiency of the present dry-cleaning industry. This second phase of research (see report KCP-94-1006 for information gathered during the first phase) was intended to allow the optimal integration of all factors of ultrasonic fabric cleaning. For this phase, Garment Care performed an extensive literature search and gathered data from other researchers worldwide. The Garment Care-AlliedSignal team developed the requirements for a prototype cleaning tank for studies and acquired that tank and the additional equipment required to use it properly. Garment Care and AlliedSignal acquired the transducers and generators from Surftran Martin-Walter in Sterling Heights, Michigan. Amway's Kelly Haley developed the test protocol, supplied hundreds of test swatches, gathered the data on the swatches before and after the tests, assisted with the cleaning tests, and prepared the final analysis of the results. AlliedSignal personnel, in conjunction with Amway and Garment Care staff, performed all the tests. Additional planning is under way for future testing by outside research facilities. The final results indicated repeatable performance and good results for single layered fabric swatches. Swatches that were cleaned as a ''sandwich,'' …
Date:
May 13, 1998
Creator:
Hand, T.E.
Object Type:
Report
System:
The UNT Digital Library
Organization and management of the plant safety evaluation of the VVER-440/230 units at Novovoronezh.
As part of the Soviet-Designed Reactor Safety (SDRS) element of the International Nuclear Safety Program (INSP), the US Department of Energy (US DOE) is funding a plant safety evaluation (PSE) project for the Novovoronezh Nuclear Power Plant (NvNPP). The Novovoronezh PSE Project is a multi-faceted project with participants from sixteen different international organizations from five different countries scattered across eleven time zones. The purpose of this project is to provide a thorough Probabilistic Risk Analysis (PRA) and Deterministic Safety Analysis (DSA) for Units 3 and 4 of the NvNPP. In addition, this project provides assistance to the operation organizations in meeting their international commitments in support of safety upgrades, and their regulatory requirements for the conduct of safety analyses. Managing this project is a complex process requiring numerous management tools, constant monitoring, and effective communication skills. Employing management tools to resolve unanticipated problems one of the keys to project success. The overall scope, programmatic context, objectives, project interactions, communications, practical hindrances, and lessons learned from the challenging performance of the PSE project are summarized in this paper.
Date:
May 13, 1999
Creator:
Afshar, C. M.; Pizzica, P.; Puglia, W. J. & Rozin, V.
Object Type:
Article
System:
The UNT Digital Library
Mechanistic Feature-Scale Profile Simulation of SiO2LPCVD by TEOS Pyrolysis
Simulation of chemical vapor deposition (CVD) in submicron features typical of semiconductor devices has been facilitated by extending the EVOLVE thin film etch and deposition simulation code to use thermal reaction mechanisms expressed in the Chemkin format. This allows consistent coupling between EVOLVE and reactor simulation codes that use Chemkin. In an application of a reactor-scale simulation code providing surface fluxes to a feature-scale simulation code, a proposed reaction mechanism for TEOS pyrolysis to deposit SiO{sub 2}, which had been applied successfully to reactor-scale simulation, is seen not to predict the low step coverage over trenches observed under short reactor residence time conditions. An apparent discrepancy between the mechanism and profile-evolution observations is a reduced degree of sensitivity of the deposition rate to the presence of reaction products, i.e., the byproduct inhibition effect is underpredicted. The cause of the proposed mechanism's insensitivity to byproduct inhibition is investigated with the combined reactor and topography simulators first by manipulating the surface to volume ratio of a simulated reactor and second by calibrating parameters in the proposed mechanism such as the calculated free energies of surface molecules. The conclusion is that the byproduct inhibition can not be enhanced to fit profile evolution data …
Date:
September 13, 1999
Creator:
CALE, TIMOTHY S.; LABUN, ANDREW H. & MOFFAT, HARRY K.
Object Type:
Article
System:
The UNT Digital Library
Post Waterflood C02 Miscible Flood in Light Oil Fluvial-Dominated Deltaic Reservoirs
Only one well remains in production in the Port Neches CO2 project; Kuhn #14. Production from this project is approaching economic limit and the project is nearing termination at this point. The work over to return Kuhn #38 to production failed and the well is currently shut in. All produced CO2 is currently being reinjected in the reservoir. The CO2 recycled volume is 2 MMCFD.
Date:
January 13, 1998
Creator:
Augustine, John
Object Type:
Report
System:
The UNT Digital Library
Pentan isomers compound flame front structure
The fuels (hexane, pentane, diethyl ether) and conditions investigated in this study are relevant to engine knock in spark- ignition engines. A review is provided of the field of low temperature hydrocarbon oxidation. Studies were made of radical and stable intermediate distribution in the front of cool flames: Maximum concentrations of H atoms and peroxy radicals were observed in the luminous zone of the cool flame front. Peroxy radicals appear before the luminous zone at 430 K due to diffusion. H atoms were found in cool flames of butane and hexane. H atoms diffuses from the luminous zone to the side of the fresh mixture, and they penetrate into the fresh mixture to a small depth. Extension of action sphear of peroxy radicals in the fresh mixture is much greater than that of H atoms due to their small activity and high concentrations.
Date:
August 13, 1995
Creator:
Mansurov, Z. A.; Mironenko, A. W.; Bodikov, D. U. & Rachmetkaliev, K. N.
Object Type:
Report
System:
The UNT Digital Library
Heavy ion fusion notes 94-1 through 94-9
This report contains information on the following topics dealing with heavy ion fusion accelerators: steering errors and corrections in a small recirculator; evaluation of a capacitive beam position monitor diagnostic for use on the heavy ion recirculator; beam steering with dipole biased electrostatic quadrupoles; estimate of emittance growth; c-probes for the recirculator; analysis of the dipole plate shape and location; and generation of electric dipole waveforms.
Date:
March 13, 1995
Creator:
Judd, D.; Rintamaki, J. & Lund, S.
Object Type:
Report
System:
The UNT Digital Library
State-of-the-Art developments in accelerator controls at the APS.
The performance requirements of the Advanced Photon Source (APS) challenge the control system in a number of areas. This paper will review a few applications of advanced technology in the control and monitoring of the APS. The application of digital signal processors (DSPs) and techniques will be discussed, both from the perspective of a large distributed multiprocessor system and from that of embedded systems. In particular, two embedded applications will be highlighted, a beam position monitor processor and a DSP-based power supply controller. Fast data distribution is often a requirement. The application of a high-speed network based on reflective memory will also be discussed in the context of the APS global orbit feedback system. Timing systems provide opportunities to apply technologies such as high-speed logic and fiber optics. Examples of the use of these technologies will also be included. Finally, every modern accelerator control system of any size requires networking. Features of the APS accelerator controls network will be discussed.
Date:
April 13, 1999
Creator:
Lenkszus, F.
Object Type:
Article
System:
The UNT Digital Library
Thermophotovoltaic Cell Temperature Measurement Issues
The power produced by photovoltaic devices changes with temperature, ranging from 0.1% to nearly 1% per degrees Celsius depending on the structure. The temperature across the surface of TPV cells will vary depending on the amount of absorbed power. Thus the temperature over a region of a wafer where there is no cell will be different from a region of the wafer containing a cell with an antireflection coating and back surface reflector. Vacuum hold-downs or back surface probes may result in local hot spots. Bonding a cell to a heat sink may not be practical in a research environment, and a temperature gradient between the heat sink and space-charge region will still exist. Procedures for determining the current versus voltage (I-V) characteristics at a given temperature are discussed. For continuous illumination measurement systems, the temperature of the heat sink or backside of the device can be directly measured. The temperature can also be inferred by placing the sample at a known temperature in the dark, and monitoring the open-circuit voltage (Voc) as a high-speed shutter is opened. The maximum Voc from this method corresponds to the temperature in the dark and the plate temperature can then be lowered until …
Date:
November 13, 1998
Creator:
Emery, K. & Moriarty, T.
Object Type:
Article
System:
The UNT Digital Library
TEWI Analysis: Its Utility, Its Shortcomings, and Its Results
The past decade has been a challenging time for the refrigeration and air conditioning industry worldwide. Provisions of the Montreal Protocol and its amendments require the phaseout of chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) compounds that have been used extensively as insulating foam blowing agents and refrigerants in refrigeration systems, heat pumps, and air conditioners. In response, hydrofluorocarbon (HFC) compounds were proposed, developed, and are starting to be used as the primary alternatives to CFCs and HCFCs. However, in 1997 under the Kyoto Protocol, industrialized nations have agreed to roll back emissions of HCFCs, carbon dioxide (CO*), and four other greenhouse gases which threaten to cause excessive global warming. The US. Department of Energy and the Alternative Fluorocarbon Environmental Acceptability Study (AFEAS) jointly sponsored research projects to identify the major applications of CFCs, HCFCs, and HFCs and to examine the impacts of these compounds and the energy use of applications employing these compounds on global warming. The five major uses of fluorocarbons based on sales were automobile air conditioning, supermarket refrigeration, unitary heat pumps and air conditioning, chillers for cooling large office buildings, and household refrigeration. Almost all of the refrigerants used in these applications are global warming gases, and if …
Date:
September 13, 1999
Creator:
Baxter, V.D.; Fischer, S.K. & Sand, J.R.
Object Type:
Article
System:
The UNT Digital Library
B-Physics prospects at CDF
Between 1992 to 1996, the CDF experiment has collected a data sample of 110 pb{sup -1} of p{bar p} collisions at {radical}s = 1.8 TeV at the Fermilab Tevatron. In the year 2001 the Tevatron will commence p{bar p} collisions again at {radical}s = 2.0 TeV delivering an integrated luminosity of 1 fb{sup -1} per year. In the mean time the CDF detector will have undergone substantial upgrades which will allow for a rich B physics program with unique capabilities. In this paper we discuss the B physics prospects at CDF with the data that will be collected during this upcoming Tevatron run.
Date:
December 13, 1999
Creator:
Papadimitriou, Vaia
Object Type:
Article
System:
The UNT Digital Library
Detector limitations, STAR
Every detector has limitations in terms of solid angle, particular technologies chosen, cracks due to mechanical structure, etc. If all of the presently planned parts of STAR [Solenoidal Tracker At RHIC] were in place, these factors would not seriously limit our ability to exploit the spin physics possible in RHIC. What is of greater concern at the moment is the construction schedule for components such as the Electromagnetic Calorimeters, and the limited funding for various levels of triggers.
Date:
July 13, 1998
Creator:
Underwood, D. G.
Object Type:
Article
System:
The UNT Digital Library
Comparison of measured and calculated composition of irradiated EBR-II blanket assemblies.
In anticipation of processing irradiated EBR-II depleted uranium blanket subassemblies in the Fuel Conditioning Facility (FCF) at ANL-West, it has been possible to obtain a limited set of destructive chemical analyses of samples from a single EBR-II blanket subassembly. Comparison of calculated values with these measurements is being used to validate a depletion methodology based on a limited number of generic models of EBR-II to simulate the irradiation history of these subassemblies. Initial comparisons indicate these methods are adequate to meet the operations and material control and accountancy (MC and A) requirements for the FCF, but also indicate several shortcomings which may be corrected or improved.
Date:
July 13, 1998
Creator:
Grimm, K. N.
Object Type:
Article
System:
The UNT Digital Library
High-Speed, High-Resolution Analog Waveform Sampling in VLSI Technology
Switched-capacitor analog memories are well-suited to a number of applications where a continuous digitization of analog signals is not needed. In data acquisition systems based on the use of an analog memory, the input waveforms are sampled and stored at a high rate for a limited period of time, and the analog samples are then retrieved at a lower rate and digitized with a slow ADC before new waveforms are acquired. The advantages of using an analog memory are lower overall power dissipation and cost, higher density and reliability, and potentially superior performance. The analog memory essentially exploits the fact that the sampling and storage of samples in a bank of analog memory cells can be accomplished at a higher rate and with a greater precision than direct digital conversion. This dissertation examines the important components of an analog memory in detail and investigates their use in a number of architectures. The research has led to the design of an analog memory that can acquire analog waveforms at sampling rates of several hundred MHz with a dynamic range and linearity of more than 12 bits, without the need for elaborate calibration and correction procedures. This is accomplished by means of …
Date:
October 13, 1998
Creator:
Haller, Gunther
Object Type:
Report
System:
The UNT Digital Library
Experimental observations to the electrical field for electrorefining of spent nuclear fuel in the Mark-IV electrorefiner.
Experimental results from the pilot scale electrorefiner (Mark-IV ER) treating spent nuclear fuel are reported in this article. The electrorefining processes were carried out in a LiCl-KCl-UCl{sub 3} electrolyte. It has been noted that spool of molten cadmium below the electrolyte plays an important role in the electrorefining operations. In addition, formations of electrical shorting path between anode baskets and the electrorefiner vessel were observed, which lessened the uranium dissolution process from anode baskets, however appeared to improve the morphology of cathode deposit. The FIDAP simulation code was used to calculate the electrical potential field distributions and the potential gradient near the cathode. The effect of the electrical shorting between anode baskets and electrorefiner vessel on the morphology of cathode products is discussed.
Date:
May 13, 1998
Creator:
Li, S. X.
Object Type:
Article
System:
The UNT Digital Library
Vector Boson Pair Production in Hadronic Collisions at Order alpha(s): Lepton Correlations and Anomalous Couplings
We present cross sections for production of electroweak vector boson pairs, WW, WZ and ZZ, in p{bar p} and pp collisions, at next-to-leading order in {alpha}{sub s}. We treat the leptonic decays of the bosons in the narrow-width approximation, but retain all spin information via decay angle correlations. We also include the effects of WWZ and WW{gamma} anomalous couplings.
Date:
July 13, 1999
Creator:
Dixon, Lance
Object Type:
Report
System:
The UNT Digital Library