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  Partner: UNT Libraries Government Documents Department
 Decade: 1990-1999
[University of North Texas: Spring 1994, Campus Map]
This is a black and white map of the University of North Texas, dating back to at least 1994. The map covers campus buildings and streets. Numbers are assigned to the building and a legend is provided beneath the map. On the lower left corner of the next page is "Spring," indicating this map was distributed during the spring term.
[University of North Texas: Summer 1999, Campus Map]
This is a black and white map of the University of North Texas, dating back to at least 1999. The map covers campus buildings and streets. Numbers are assigned to the building and a legend is provided beneath the map. On the lower left corner of the next page is "Summer," indicating this map was distributed during the summer term. Printed on the upper left corner of the page is a compass for reference.
User`s manual for the radioactive decay and accumulation code RADAC
The RADAC computer code calculates radioactive decay and accumulation of decayed products using an algorithm based on the direct use of the Bateman equations and referred to here as the yield factor method. This report explains the yield factor method, gives an overview of the various modules in the RADAC code system, and describes the decay and accumulation code in detail. The RADAC code has capacity for two waste types and can accommodate up to 60 years of annual waste inputs. Decay times as high as 1 million years can be calculated. The user supplies the undecayed composition and radioactivity of the waste placed in storage each year. The code calculates the decayed composition, radioactivity, and thermal power of the accumulated waste at the end of each year and gives the results in terms of grams and curies of individual radionuclides. Calculations can be made for up to 19 waste storage sites in a single run. For each site and each waste type, calculations can be made by 1-year steps up to 60 years, by 10-year steps to 160 years, and by 6 discrete steps to 1 million years. Detailed outputs can be printed for each waste site and each time step by individual radionuclides. Summarized outputs are also available. Excluding data-preparation time, RADAC requires about 2 min to run 19 waste sites with two types of transuranic waste at each site, using a 486 DX computer with a clock speed of 33 MHz. Because RADAC uses a preselected set of decay times and does not make in-reactor calculations, it should not be viewed as a substitute for ORIGEN2. RADAC is intended for use in applications in which accumulations at the decay times provided by the code are sufficient for the user`s purposes.
Initiation of environmentally-assisted cracking in low-alloy steels
Environmentally-Assisted Cracking (EAC) in low alloy steels is activated by a critical level of sulfide ions at the crack tip, which is produced from dissolution of sulfide inclusions (MnS, FeS, etc.) in the steel following exposure by a growing crack. EAC of concern herein is the increase of fatigue crack growth rate of up to 40 to 100 times the rate in air that occurs at 240--300 C in high temperature LWR or boiler water environments. The initiation of EAC is the onset of the higher fatigue crack growth rates in fully developed cracks already presumed to be present due to fatigue, stress corrosion cracking, or induced by fabrication. Initiation of EAC is induced by a change in loading parameters causing the fatigue crack growth rate to increase from a small multiple (2--4) to 40--100 times the air rate. A steady state theory developed by Combrade, suggests that EAC will initiate only above a critical crack velocity and cease below this same velocity. However, more recent tests show that EAC can persist down to much lower velocities (100 times lower) in low oxygen water at slightly lower temperatures. A special set of experiments on high sulfur plate material demonstrate that EAC will not initiate from surface cracks with low sulfide inventories at low crack tip velocities. Transient diffusion calculations show that a finite crack extension at a high crack tip velocity is necessary to initiate EAC, providing a possible explanation for the lack of high crack growth observations reported in low alloy steels in structural applications involving low oxygen environments.
Stratigraphic data for wells at and near the Idaho National Engineering Laboratory, Idaho
A stratigraphic data base containing 230 stratigraphic units in 333 wells was constructed for deposits that make up the unsaturated zone and the Snake River Plain aquifer at and near INEL in eastern Idaho. Stratigraphic units, which were identified and correlated using data from numerous outcrops, 26 continuous cores, and 328 natural-gamma logs available in Dec. 1993, include 121 basalt-flow groups, 102 sedimentary interbeds, 6 andesite-flow groups, and 1 rhyolite dome. By volume, basalt flows make up about 90% of the deposits underlying most of this 890 mi{sup 2} area. Basalt, sediment, andesite, and rhyolite were identified from outcrops and cores that were selectively evaluated. Stratigraphic units were correlated using these data and natural-gamma logs. Best correlations were for basalt and sediment at Test Area North, the Naval Reactors Area, the Test Reactor Area, ICPP, and the Radioactive Waste Management Complex (RWMC), where most cores and 2/3 of the logs were obtained. Correlations range from good at the RWMC to uncertain the eastern half of the study area. A computer diskette containing the data is included.
Analysis of hydrogen vehicles with cryogenic high pressure storage
Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LIQ) or ambient-temperature compressed hydrogen (CH2). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). This paper shows an evaluation of the applicability of the insulated pressure vessels for light-duty vehicles. The paper shows an evaluation of evaporative losses and insulation requirements and a description of the current experimental plans for testing insulated pressure vessels. The results show significant advantages to the use of insulated pressure vessels for light-duty vehicles.
A statistical mechanical description of biomolecular hydration
We present an efficient and accurate theoretical description of the structural hydration of biological macromolecules. The hydration of molecules of almost arbitrary size (tRNA, antibody-antigen complexes, photosynthetic reaction centre) can be studied in solution and in the crystal environment. The biomolecular structure obtained from x-ray crystallography, NMR, or modeling is required as input information. The structural arrangement of water molecules near a biomolecular surface is represented by the local water density analogous to the corresponding electron density in an x-ray diffraction experiment. The water-density distribution is approximated in terms of two- and three-particle correlation functions of solute atoms with water using a potentials-of-mean-force expansion.
Stress and Defect Control in GaN Using Low Temperature Interlayers
In organometallic vapor phase epitaxial growth of Gail on sapphire, the role of the low- temperature-deposited interlayers inserted between high-temperature-grown GaN layers was investigated by in situ stress measurement, X-ray diffraction, and transmission electron microscopy. Insertion of a series of low temperature GaN interlayers reduces the density of threading dislocations while simultaneously increasing the tensile stress during growth, ultimately resulting in cracking of the GaN film. Low temperature AIN interlayers were found to be effective in suppressing cracking by reducing tensile stress. The intedayer approach permits tailoring of the film stress to optimize film structure and properties.
Evaluation of a non-cyanide gold plating process for switch tubes
Switch tubes are used in nuclear weapon firing sets and are required to be reliable and impervious to gas permeation for many years. To accomplish this, a gold plated coating of approximately 25 microns is required over all metal surfaces on the tube exterior. The gold has historically been plated using gold cyanide plating chemistry. In this work we proposed to replace the cyanide plating bath with an environmentally friendlier sulfite gold plating bath. Low and high pH sulfite plating chemistries were investigated as possible replacements for the cyanide gold plating chemistry. The low pH plating chemistry demonstrated a gold plated coating which met the high purity, grain size, and hardness requirements for switch tubes. The high pH chemistry was rejected primarily because the hardness of the gold plated coatings was too high and exceeded switch tube coating requirements. A problem with nodule formation on the gold plated surface using the low pH chemistry had to be resolved during this evaluation. The nodule formation was postulated to be produced by generation of SO{sub 2} in the low pH bath causing gold to be precipitated out when the sulfite concentration falls below a minimum level. The problem was resolved by maintaining a higher sulfite concentration and providing an active filtration system during plating. In this initial study, there were no major obstacles found when using a sulfite gold bath for switch tube plating, however, further work is needed on bath control and bath life before adopting it as the primary plating chemistry.
LANSCE beam current limiter
The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. Active instrumentation, such as the Beam Current Limiter, is a component of the RSS. The current limiter is designed to limit the average current in a beam line below a specific level, thus minimizing the maximum current available for a beam spill accident. The beam current limiter is a self-contained, electrically isolated toroidal beam transformer which continuously monitors beam current. It is designed as fail-safe instrumentation. The design philosophy, hardware design, operation, and limitations of the device are described.
Formulation and make-up of simulate dilute water, low ionic content aqueous solution
This procedure describes the formulation and make-up of Simulated Dilute Water (SOW), a low-ionic-content water to be used for Activity E-20-50, Long-Term Corrosion Studies. This water has an ionic content which is nominally a factor of ten higher than that of representative waters at or near Yucca Mountain. Representative waters were chosen as J-13 well water [Harrar, 1990] and perched water at Yucca Mountain [Glassley, 1996]. J-13 well water is obtained from ground water that is in contact with the Topopah Spring tuff, which is the repository horizon rock. The perched water is located in the Topopah Spring tuff, but below the repository horizon and above the water table. A nominal times ten higher ionic content was chosen to simulate the effect of ionic concentrating due to elevated temperature water flowing through fractures where salts and minerals have been deposited due to evaporation and boiling.
ORNL contribution to the IAEA bcnchmark problem on fission reactor decommissioning
Recently the International Atomic Energy Agency (IAEA) selected a benchmark problem for calculation of radioactivity inventories and dose estimates necessary for fission reactor decommissioning. Several researchers were invited to participate in the solution of this benchmark problem set. The contribution from Oak Ridge National Laboratory (ORNL) is presented in this paper.
Dependence of H-mode power threshold on global and local edge parameters
Measurements of local electron density n{sub e}, electron temperature T{sub e}, and ion temperature T{sub i} have been made at the very edge of the plasma just prior to the transition into H-mode for four different single parameter scans in the DIII-D tokamak. The means and standard derivations of n{sub e}, T{sub e}, and T{sub i} under these conditions for a value of the normalized toroidal flux of 0.98 are respectively, 1.5 {+-} 0.7 x 10{sup 19} m{sup -3}, 0.051 {+-} 0.016 keV, and 0.14 {+-} 0.03 keV. The threshold condition for the transition is more sensitive to temperature than to density. The data indicate that the dependence is not as simple as a requirement for a fixed value of the ion collisionality.
Edge conduction in vacuum glazing
Vacuum glazing is a form of low-conductance double glazing using in internal vacuum between the two glass sheets to eliminate heat transport by gas conduction and convection. An array of small support pillars separates the sheets; fused solder glass forms the edge seal. Heat transfer through the glazing occurs by radiation across the vacuum gap, conduction through the support pillars, and conduction through the bonded edge seal. Edge conduction is problematic because it affects stresses in the edge region, leading to possible failure of the glazing; in addition, excessive heat transfer because of thermal bridging in the edge region can lower overall window thermal performance and decrease resistance to condensation. Infrared thermography was used to analyze the thermal performance of prototype vacuum glazings, and, for comparison, atmospheric pressure superwindows. Research focused on mitigating the edge effects of vacuum glazings through the use of insulating trim, recessed edges, and framing materials. Experimentally validated finite-element and finite-difference modeling tools were used for thermal analysis of prototype vacuum glazing units and complete windows. Experimental measurements of edge conduction using infrared imaging were found to be in good agreement with finite-element modeling results for a given set of conditions. Finite-element modeling validates an analytic model developed for edge conduction.
Assessment of mercury in the Savannah River Site environment
Mercury has been valued by humans for several millennia. Its principal ore, cinnabar, was mined for its distinctive reddish-gold color and high density. Mercury and its salts were used as medicines and aphrodisiacs. At SRS, mercury originated from one of the following: as a processing aid in aluminum dissolution and chloride precipitation; as part of the tritium facilities` gas handling system; from experimental, laboratory, or process support facilities; and as a waste from site operations. Mercury is also found in Par Pond and some SRS streams as the result of discharges from a mercury-cell-type chlor-alkali plant near the city of Augusta, GA. Reactor cooling water, drawn from the Savannah River, transported mercury onto the SRS. Approximately 80,000 kg of mercury is contained in the high level waste tanks and 10,000 kg is located in the SWDF. Additional quantities are located in the various seepage basins. In 1992, 617 wells were monitored for mercury contamination, with 47 indicating contamination in excess of the 0.002-ppm EPA Primary Drinking Water Standard. More than 20 Savannah River Ecology Laboratory (SREL) reports and publications pertinent to mercury (Hg) have been generated during the last two decades. They are divided into three groupings: SRS-specific studies, basic studies of bioaccumulation, and basic studies of effect. Many studies have taken place at Par Pond and Upper Three Runs Creek. Mercury has been detected in wells monitoring the groundwater beneath SRS, but not in water supply wells in excess of the Primary Drinking Water Limit of 0.002 ppm. There has been no significant release of mercury from SRS to the Savannah River. While releases to air are likely, based on process knowledge, modeling of the releases indicates concentrations that are well below the SCDHEC ambient standard.
Applications of RQMD to Bose-Einstein correlations
Source size parameters measured via two-particle interferometry in experiment NA44 for 200 GeV/nucleon S+Pb collisions are compared to calculations using the RQMD event generator. Reasonable agreement is found in most cases. Based on this agreement, the model is used to study some of the interesting details of the collision dynamics which are not easily measured. 27 refs., 4 figs., 1 tab.
Rectangular Schlumberger resistivity arrays for delineating vadose zone clay-lined fractures in shallow tuff
Rectangular Schlumberger arrays can be used for 2-dimensional lateral profiling of apparent resistivity at a unique current electrode separation, hence single depth of penetration. Numerous apparent resistivity measurements are collected moving the potential electrodes (fixed MN spacing) within a rectangle of defined dimensions. The method provides a fast, cost-effective means for the collection of dense resistivity data to provide high-resolution information on subsurface hydrogeologic conditions. Several rectangular Schlumberger resistivity arrays were employed at Los Alamos National Laboratory (LANL) from 1989 through 1995 in an area adjacent to and downhill from an outfall pipe, septic tank, septic drainfield, and sump. Six rectangular arrays with 2 AB spacings were used to delineate lateral low resistivity anomalies that may be related to fractures that contain clay and/or vadose zone water. Duplicate arrays collected over a three year time period exhibited very good data repeatability. The properties of tritium make it an excellent groundwater tracer. Because tritium was present in discharged water from all of the anthropogenic sources in the vicinity it was used for this purpose. One major low resistivity anomaly correlates with relatively high tritium concentrations in the tuff. This was determined from borehole samples collected within and outside of the anomalous zone. The anomaly is interpreted to be due to fractures that contain clay from the soil profile. The clay was deposited in the fractures by aeolian processes and by surface water infiltration. The fractures likely served as a shallow vadose zone groundwater pathway.
Measurements of laser imprint by XUV radiography using an x-ray laser
We have developed a technique for studying the imprint of a laser beam on a thin foil using an x-ray laser as an XUV backlighter and XUV multilayer optics. This technique allows us to measure small fractional variations in the foil thickness due to hydrodynamics imprinted by direct laser irradiation. We present results of imprinted modulation and growth due to a low intensity 0.53 {mu}m drive beam incident on a 2 {mu}m Al foil using a germanium x-ray laser at the Vulcan facility. We present measurements of the modulation due to static RPP, SSD smoothed, and ISI smoothed speckle patterns at 0.53 {mu}m irradiation.
Validation of nuclear criticality safety software and 27 energy group ENDF/B-IV cross sections. Revision 1
The original validation report, POEF-T-3636, was documented in August 1994. The document was based on calculations that were executed during June through August 1992. The statistical analyses in Appendix C and Appendix D were completed in October 1993. This revision is written to clarify the margin of safety being used at Portsmouth for nuclear criticality safety calculations. This validation gives Portsmouth NCS personnel a basis for performing computerized KENO V.a calculations using the Lockheed Martin Nuclear Criticality Safety Software. The first portion of the document outlines basic information in regard to validation of NCSS using ENDF/B-IV 27-group cross sections on the IBM3090 at ORNL. A basic discussion of the NCSS system is provided, some discussion on the validation database and validation in general. Then follows a detailed description of the statistical analysis which was applied. The results of this validation indicate that the NCSS software may be used with confidence for criticality calculations at the Portsmouth Gaseous Diffusion Plant. For calculations of Portsmouth systems using the specified codes and systems covered by this validation, a maximum k{sub eff} including 2{sigma} of 0.9605 or lower shall be considered as subcritical to ensure a calculational margin of safety of 0.02. The validation of NCSS on the IBM 3090 at ORNL was extended to include NCSS on the IBM 3090 at K-25.
TPX: Contractor preliminary design review. Volume 2, PF systems engineering
This system development specification covers the Poloidal Field (PF) Magnet System, WBS 14 in the Princeton Plasma Physics Laboratory TPX Program to build a tokamak fusion reactor. This specification establishes the performance, design, development and test requirements of the PF Magnet System.
Unit decontamination and dismantlement (D&D) costs
A series of relationships have been developed for estimating unit decontamination and dismantlement (D&D) costs for a number of building types which may be applied in the absence of other data to obtain rough order-of-magnitude (ROM) cost estimates for D&D activities. The relationships were developed using unit D&D costs for a number of building structure types at the Department of Energy Fernald site. These unit costs into account the level of radioactive contamination as well as the, building size.
Integration of sample analysis method (SAM) for polychlorinated biphenyls
A completely integrated Sample Analysis Method (SAM) has been tested as part of the Contaminant Analysis Automation program. The SAM system was tested for polychlorinated biphenyl samples using five Standard Laboratory Modules{trademark}: two Soxtec{trademark} modules, a high volume concentrator module, a generic materials handling module, and the gas chromatographic module. With over 300 samples completed within the first phase of the validation, recovery and precision data were comparable to manual methods. Based on experience derived from the first evaluation of the automated system, efforts are underway to improve sample recoveries and integrate a sample cleanup procedure. In addition, initial work in automating the extraction of semivolatile samples using this system will also be discussed.
RCRA Information Brief, June 1996: Conditional remedies under RCRA correction action
This document describes conditional remedies under RCRA corrective action. The definition of conditional remedies, criteria that must be met, applications to DOE facilities, applicable clean-up standards, and implementation of conditional remedies are discussed in the document.
HIPPI: What is it, where did it come from, and where is it going?
The first commercial High-Performance Parallel Interface (HIPPI) equipment was delivered in 1988, and HIPPI is the current interface of choice for supercomputers and other high end equipment. HIPPI currently supports data rates of 800 and 1600 Mbit/s. The evolution of HIPPI will be described, including some of the design choices made, describing where the author feels each came from, and the strengths and weaknesses of each. The HIPPI standards committee is now working on a new physical layer interface supporting data transfer rates of 6. 4 Gbit/s, an increase of eight times the current common HIPPI rate. The design objectives will be discussed, and the new interface will be described.
LLW notes: Volume 10, Number 6
The Low-Level Radioactive Waste Forum is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.
Quantitative prediction of stresses during thermoset cure
Two thin-walled Al tubes were filled with epoxy which were cured isothermally; one tube was instrumented with strain gauges, and the other with thermocouples. Finite element codes were used. Predicted and measured centerline hoop strains are shown; predictions and measurements agree. This is being applied to encapsulated components.
Advanced in-duct sorbent injection for SO{sub 2} control. Topical report number 3, Subtask 2.3: Sorbent optimization
The objective of this research project is to develop second-generation duct injection technology as a cost-effective compliance option for the 1990 Clean Air Act Amendments. Specific process performance goals are to achieve 90% SO{sub 2} removal and 60% sorbent utilization efficiency. Research is focused on the Advanced Coolside process, which has shown the potential of achieving these targets. The objective of Subtask 2.3, Sorbent Optimization, was to explore means of improving performance and economics of the Advanced Coolside process through optimizing the sorbent system. Pilot plant tests of commercial and specially prepared hydrated limes showed that the process is relatively insensitive to sorbent source. This can be an important economic advantage, allowing the use of the lowest cost sorbent available at a site. A pilot plant hydration study conducted in cooperation with Dravo Lime Company further indicated the relative insensitivity of process performance to lime source and to lime physical properties. Pilot plant tests indicated that the use of very small amounts of additives in the Advanced Coolside process can improve performance under some circumstances; however, additives are not necessary to exceed process performance targets.
Mechanisms of ionizing-radiation-induced gain degradation in lateral PNP BJTs
The physical mechanisms for gain degradation in laterals PNP bipolar transistors are examined experimentally and through simulation. The effect of increased surface recombination velocity at the base surface is moderated by positive oxide charge.
Hydrologic review services. Final project report, May 24--December 31, 1993
Research on the runoff, sediment, and contaminant transport in Big Buck Canyon at the Los Alamos National Laboratory began in 1993. The final research goal is to estimate how fast and how much contaminated sediment is moving in the canyon. Due to equation of state experiments involving high explosives, soils in the vicinity of the three test sites have been contaminated with heavy metals such as uranium and cadmium. There are three main parts to the research that will eventually be combined to address the final goal of estimating total contaminant movement. The first part involves the collection and interpretation of experimental field data, such as rainfall and runoff amounts. The second part involves numerical modeling the watershed response to rainfall inputs. The third part involves experimental chemistry work to evaluate the concentration of contaminants in a representative sample of sediment. The details about the model development and testing are presented. The simulation of a large flood in 1991 did not compare well with observations of the event. The model seriously underpredicted the flow out of the watershed because the value of the hydraulic conductivity in the channel was too large. The infiltration of water into the channel bed, known as transmission losses, is a direct function of hydraulic conductivity. Field measurements of hydraulic conductivity yielded values that are much larger than those found in the literature. Consequently, the high input values of hydraulic conductivity produced model results that underestimated the flow. Future research on the process of transmission losses is recommended to resolve this issue and improve the accuracy of the model results.
State and national energy environmental risk analysis systems for underground injection control. Final report, April 7, 1992--May 31, 1995
The purpose of this effort is to develop and demonstrate the concept of a national Energy and Environmental Risk Analysis System that could support DOE policy analysis and decision-making. That effort also includes the development and demonstration of a methodology for assessing the risks of groundwater contamination from underground injection operations. EERAS is designed to enhance DOE`s analytical capabilities by working with DOE`s existing resource analysis models for oil and gas. The full development of EERAS was not planned as part of this effort. The design and structure for the system were developed, along with interfaces that facilitate data input to DOE`s other analytical tools. The development of the database for EERAS was demonstrated with the input of data related to underground injection control, which also supported the risk assessment being performed. The utility of EERAS has been demonstrated by this effort and its continued development is recommended. Since the absolute risk of groundwater contamination due to underground injection is quite low, the risk assessment methodology focuses on the relative risk of groundwater contamination. The purpose of this methodology is to provide DOE with an enhanced understanding of the relative risks posed nationwide as input to DOE decision-making and resource allocation. Given data problems encountered, a broad assessment of all oil reservoirs in DOE`s resource database was not possible. The methodology was demonstrated using a sample of 39 reservoirs in 15 states. While data difficulties introduce substantial uncertainties, the results found are consistent with expectations and with prior analyses. Therefore the methodology for performing assessments appears to be sound. Recommendations on steps that can be taken to resolve uncertainties or obtain improved data are included in the report.
National Laboratories and Internatioanl Partnering
For nearly fifty years the US held a dominant position in research and development in the free world. The situation has changed dramatically in the last decade. Countries around the world realize that to foster sustainable economic growth, they must build and maintain a foundation in science and technology. The time in which a country could base its gross national product solely on extraction of raw materials or on people-intensive manufacturing is drawing to a close. The funding for research and development has been growing in the rest of the world, while US expenditures have not kept pace. In 1961, the United States funded 71 `?40 of the world's R&D. It is estimated that the US contribution to research and development fimding today has reached the 3 3o/0 level, and will drop to 26o/0 of the world's total by 2003.1 In 1981 US government spending per capita on non-defense research and development was nearly fifty percent above our major competitors; by 2002 it is projected to be f@ percent below them.2 This trend has a profound impact on how research and development institutions in the United States plan for their future technical growth. Sandia National Laboratories, as one of the largest US-government tided research establishments, has been watching this trend for some time. %ndi~ focusing on the Laboratories' missions in nuclear weapons and related defense systems, energy security, environmental integrity, and emerging national challenges, is committed to bringing the best in world-class technology to bear on the nation's problems. We realize maintaining our state-of-the-art technolo=~ base requires we look not only to domestic sources in universities, industries and other laboratories, but also to sources overseas. The realization that we must be "worldwide gatherers of technology" has led Sandia National Laboratories to consider the question of international partnering in some detaiI. As a national laboratory with a national security mission we are well aware of the issues that we face in pursuing international collaborations. In order to make the proper decisions, we are interested in understanding the history of such partnerships, when they are appropriate, why we expect them to be important, the risks they present and what we can do to mitigate those risks.
Experimental assessment of absorbed dose to mineralized bone tissue from internal emitters: An electron paramagnetic resonance study
EPR resonances attributable to radiation-induced centers in hydroxyapatite were not detectable in bone samples supplied by the USTUR. These centers are the basis for imaging and dose assessment. Presumable, the short range of the alpha particles emitted precluded the formation of appreciable amounts of hydroxyapatite centers. However, one bone sample did offer a suggestion of hydroxyapatite centers and newly-developed methods to extract this information will be pursued.
Low-temperature geothermal resources of Washington
This report presents information on the location, physical characteristics, and water chemistry of low-temperature geothermal resources in Washington. The database includes 941 thermal (>20C or 68F) wells, 34 thermal springs, lakes, and fumaroles, and 238 chemical analyses. Most thermal springs occur in the Cascade Range, and many are associated with stratovolcanoes. In contrast, 97 percent of thermal wells are located in the Columbia Basin of southeastern Washington. Some 83.5 percent are located in Adams, Benton, Franklin, Grant, Walla Walla, and Yakima Counties. Yakima County, with 259 thermal wells, has the most. Thermal wells do not seem to owe their origin to local sources of heat, such as cooling magma in the Earth`s upper crust, but to moderate to deep circulation of ground water in extensive aquifers of the Columbia River Basalt Group and interflow sedimentary deposits, under the influence of a moderately elevated (41C/km) average geothermal gradient.
Liquid natural gas as a transportation fuel in the heavy trucking industry. Second quarterly progress report, [October 1, 1994-- December 30, 1994]
Emphasis of this project focuses on LNG research issues in use of liquefied natural as a transportation fuel in heavy trucking industry. These issues maybe categorized as: task 1--direct diesel replacement with LNG fuel; and task 2--short and long term storage. Accomplishments for these tasks are discussed. Task 1 consists of atomization, fundamentals of direct replacement, and distribution of emissions. Task 2 includes modified adsorbents, vent gas, and LNG storage at moderate conditions.
Comprehensive supernate treatment: Task summary
Short communication.
Diagnosis of high-temperature implosions using low- and high-opacity Krypton lines
High-temperature laser target implosions can be achieved by using relatively thin-shell targets, and they can be. diagnosed by doping the fuel with krypton and measuring K-shell and L-shell lines. Electron temperatures of up to 5 keV at modest compressed densities ({approximately}1-5g/cm{sup 3}) are predicted for such experiments, with ion temperatures peaking above 10 keV at the center. It is found that the profiles of low-opacity (optically thin) lines in the expected density range are dominated by the Doppler broadening and can provide a measurement of the ion temperature if spectrometers of spectral resolution {Delta}{lambda}/{lambda} {ge} 1000 are used. For high-opacity lines, obtained with a higher krypton fill pressure, the measurement of the escape factor can yield the {rho}R of the compressed fuel. At higher densities, Stark broadening of low-opacity lines becomes important and can provide a density measurement, whereas lines of higher opacity can be used to estimate the extent of mixing.
Condensed-phase decomposition in thermally-aged explosives
In previous work, the isothermal decomposition of nitrocellulose (NC) was examined using two substantially different experimental techniques that are being developed to investigate condensed-phase chemistry occurring during the thermal decomposition of a variety of explosives. The confined isothermal aging technique involved confined thin-film samples heated to temperatures of 150 to 170{degrees}C, for 1 to 72 hours. Condensed-phase chemistry was monitored real-time using FTIR. Results indicated that the first step in decomposition was scission of the O-NO{sub 2} bond and subsequent formation of carbonyl and hydroxyl products. Scission of the O-NO{sub 2} bond appeared to occur by a first-order reaction. Additional unconfined rapid isothermal decomposition experiments with NC have been completed and are described in this paper. Those additional experiments extended the previous work and investigated the effect of varying film thickness (from about 0.2 to 0.6 microns), varying temperature (from about 420 to 640{degrees}C), and using {sup 15}NO{sub 2}-labled NC. The results indicated that decomposition of NC appears to involve at least two principal mechanisms: (1) O-NO{sub 2} bond scission, which is accompanied by carbonyl or hydroxyl formation, and (2) polymer fragmentation. These two mechanisms occur simultaneously. At temperatures of 170{degrees}C, or lower, polymer fragmentation appears negligible, but at temperatures of 420{degrees}C, or higher, polymer fragmentation is appreciable and occurs at rates comparable to those for O-NO{sub 2} bond scission. While polymer fragmentation may be associated with O-NO{sub 2} bond scission, at higher temperatures, additional steps must be involved in the fragmentation mechanism. At each end of the temperatures range from about 150 to 420{degrees}C, the rate of O-NO{sub 2} bond scission appears reasonably consistent with a mechanism dominated by a first-order decomposition step.
Engineered materials characterization report, volume 3 - corrosion data and modeling update for viability assessments
This Engineered Materials Characterization Report (EMCR), Volume 3, discusses in considerable detail the work of the past 18 months on testing the candidate materials proposed for the waste-package (WP) container and on modeling the performance of those materials in the Yucca Mountain (YM) repository setting This report was prepared as an update of information and serves as one of the supporting documents to the Viability Assessment (VA) of the Yucca Mountain Project. Previous versions of the EMCR have provided a history and background of container-materials selection and evaluation (Volume I), a compilation of physical and mechanical properties for the WI� design effort (Volume 2), and corrosion-test data and performance-modeling activities (Volume 3). Because the information in Volumes 1 and 2 is still largely current, those volumes are not being revised. As new information becomes available in the testing and modeling efforts, Volume 3 is periodically updated to include that information.
Rocks as poroelastic composites
In Biot's theory of poroelasticity, elastic materials contain connected voids or pores and these pores may be filled with fluids under pressure. The fluid pressure then couples to the mechanical effects of stress or strain applied externally to the solid matrix. Eshelby's formula for the response of a single ellipsoidal elastic inclusion in an elastic whole space to a strain imposed at infinity is a very well-known and important result in elasticity. Having a rigorous generalization of Eshelby's results valid for poroelasticity means that the hard part of Eshelby' work (in computing the elliptic integrals needed to evaluate the fourth-rank tensors for inclusions shaped like spheres, oblate and prolate spheroids, needles and disks) can be carried over from elasticity to poroelasticity - and also thermoelasticity - with only trivial modifications. Effective medium theories for poroelastic composites such as rocks can then be formulated easily by analogy to well-established methods used for elastic composites. An identity analogous to Eshelby's classic result has been derived [Physical Review Letters 79:1142-1145 (1997)] for use in these more complex and more realistic problems in rock mechanics analysis. Descriptions of the application of this result as the starting point for new methods of estimation are presented.
Test fire environmental testing operations at Mound Applied Technologies
This paper describes Mound Laboratory`s environmental testing operations. The function of environmental testing is to perform quality environmental (thermal, mechanical, spin, resistance, visual) testing/conditioning of inert/explosive products to assure their compliance with specified customer acceptance criteria. Capabilities, organization, equipment specifications, and test facilities are summarized.
Subpilot-scale testing of acoustically enhanced cyclone collectors. Final report, September 1988--September 1994
Gas turbines are used to recover energy from high temperature exhaust gases in coal-fired pressurized-fluidized bed, combined-cycle power generation systems. However, prior to entering the turbine hot-section, the majority of the fly ash must be removed in order to protect the turbine components from erosion, corrosion, and deposition of the ash. The U.S. Department of Energy under the direction of the Morgantown Energy Technology Center (METC) sponsored the development of an acoustically enhanced cyclone collector which offers the potential of achieving environmental control standards under Pressurized Fluid Bed Combustors (PFBC) conditions without the need for post-turbine particulate control. Pulse combustors developed by Manufacturing and Technology Conversation International, Inc. (MTCI) produced the acoustic power necessary to agglomerate ash particles into sizes large enough to be collected in a conventional cyclone system. A hot gas cleanup system that meets both turbine protection and emissions requirements without post-turbine particulate controls would also have improved overall system economics.
Heat capacity of quantum adsorbates: Hydrogen and helium on evaporated gold films
The author has constructed an apparatus to make specific heat measurements of quantum gases adsorbed on metallic films at temperatures between 0.3 and 4 K. He has used this apparatus to study quench-condensed hydrogen films between 4 and 923 layers thick with J = 1 concentrations between 0.28 and 0.75 deposited on an evaporated gold surface. He has observed that the orientational ordering of the J = 1 molecules depends on the substrate temperature during deposition of the hydrogen film. He has inferred that the density of the films condensed at the lowest temperatures is 25% higher than in bulk H{sub 2} crystals and have observed that the structure of those films is affected by annealing at 3.4 K. The author has measured the J = 1 to J = 0 conversion rate to be comparable to that of the bulk for thick films; however, he found evidence that the gold surface catalyzes conversion in the first two to four layers. He has also used this apparatus to study films of {sup 4}He less than one layer thick adsorbed on an evaporated gold surface. He shows that the phase diagram of the system is similar to that for {sup 4}He/graphite although not as rich in structure, and the phase boundaries occur at different coverages and temperatures. At coverages below about half a layer and at sufficiently high temperatures, the {sup 4}He behaves like a two-dimensional noninteracting Bose gas. At lower temperatures and higher coverages, liquidlike and solidlike behavior is observed. The Appendix shows measurements of the far-infrared absorptivity of the high-{Tc} superconductor La{sub 1.87}Sr{sub 0.13}CuO{sub 4}.
Investigation of the effect of microstructure on the R-Curve behavior of metal-ceramic composites
An investigation was made into the effect of microstructure on the peak toughness and shape of the crack growth resistance curves for two ceramic-metal composites. An Al{sup 2}O{sup 3}/Al composite formed by Reactive Metal Penetration was used along with an AlN/Al composite formed using a reactive infiltration technique. The results indicate that the toughness increases with an increase in the volume fraction of the metal phase for a particular composite composition, and the peak toughness and shape of the R-Curve also depend on the composite microstructure and metal composition.
Developments of advanced hot-gas desulfurization sorbents. Quarterly technical progress report, April--June 1995
The objectives of this project are to develop hot-gas cleanup sorbents for relatively lower temperature application, with emphasis on the temperature range from 343-538{degrees}C. The candidate sorbents include highly dispersed mixed metal oxides of zinc, iron, copper, cobalt and molybdenum. The specific objective in the successful preparation of H{sub 2}S absorbents will be to generate as high and as stable a surface area as possible, in order to develop suitable sorbent, that are sufficiently reactive and regenerable at the relatively lower temperatures of interest in this work. A number of formulations will be prepared and screened for testing in a 1/2-inch fixed bed reactor at high pressure (1 to 20 atm) and high temperatures using simulated coal-derived fuel-gases. Screening criteria will include, chemical reactivity, stability, and regenerability over the temperature range of 343{degrees}C (650{degrees}F) to 538{degrees}C (1000{degrees}F). Each formulation will be tested for up to 5 cycles of absorption and regeneration. To prevent sulfation, catalyst additives will be investigated, which would promote a lower ignition of the regeneration. Selected superior formulation will be tested for long term (up to least 30 cycles) durability and chemical reactivity in the reactor.
Plasma rotation and the radial electric field during off-axis NBI in the DIII-D tokamak
Experiments have been carried out on the DIII-D tokamak to investigate whether off-axis NBI can: (a) drive significant perpendicular flow to lead to increased suppression of turbulence and improved confinement, and (b) be used to control the radial electric field profile. Measurements of both impurity ion poloidal and toroidal rotation profiles were made using charge exchange recombination spectroscopy. These experiments used a low current, low elongation (I{sub p} = 0.5 MA, {kappa} = 1.2) plasma whose magnetic axis was shifted 36 cm vertically upward from the vessel midplane and then shifted downward to be centered on the midplane later in the discharge. 10.7 MW of beam power was applied to maximize NBI effect while operating at low target densities and high temperature to minimize poloidal damping. Results from these experiments show a slight increase in impurity ion poloidal rotation velocity during the vertical shifted phase of off-axis NBI discharge. The toroidal rotation profile is more peaked during off-axis NBI. Both these effects lead to a change in the V x B contribution to the radial electric field during off-axis NBI.
Laboratory Directed Research & Development program. Annual report to the Department of Energy
This report briefly discusses the following projects coordinated at Brookhaven National Laboratory: investigation of the utility of max-entropy methods for the analysis of powder diffraction data; analysis of structures and interactions of nucleic acids and proteins by small angle x-ray diffraction; relaxographic MRI and functional MRI; very low temperature infra-red laser absorption as a potential analytical tool; state-resolved measurements of H{sub 2} photodesorption: development of laser probes of H{sub 2} for in-situ accelerator measurements; Siberian snake prototype development for RHIC; synthesis and characterization of novel microporous solids; ozone depletion, chemistry and physics of stratospheric aerosols; understanding the molecular basis for the synthesis of plant fatty acids possessing unusual double bond positions; structure determination of outer surface proteins of the Lyme disease spirochete; low mass, low-cost multi-wire proportional chambers for muon systems of collider experiments; theory of self-organized criticality; development of the PCR-SSCP technique for the detection, at the single cell level, of specific genetic changes; feasibility of SPECT in imaging of F-18 FDG accumulation in tumors; visible free electron laser oscillator experiment; study of possible 2 + 2 TeV muon-muon collider; ultraviolet FEL R & D; precision machining using hard x-rays; new directions in in-vivo enzyme mapping: catechol-O-methyltransferase; proposal to develop a high rate muon polarimeter; development of intense, tunable 20-femtosecond laser systems; use of extreme thermophilic bacterium thermatoga maritima as a source of ribosomal components and translation factors for structural studies; and biochemical and structural studies of Chaperon proteins from thermophilic bacteria and other experiments.
Advanced gas turbine systems research quarterly report, July-- September 1995
Major accomplishments and reports issued during the quarter are reported.
RG analysis of magnetic catalysis in dynamical symmetry breaking
We perform the renormalization group analysis on the dynamical symmetry breaking under strong external magnetic field, studied recently by Gusynin, Miransky and Shovkovy. We find that any attractive four-Fermi interaction becomes strong in the low energy, thus leading to dynamical symmetry breaking. When the four-Fermi interaction is absent, the {beta}-function for the electromagnetic coupling vanishes in the leading order in 1/N. By solving the Schwinger-Dyson equation for the fermion propagator, we show that in 1/N expansion, for any electromagnetic coupling, dynamical symmetry breaking occurs due to the presence of Landau energy gap by the external magnetic field. 5 refs.
Multiscale Modeling of Recrystallization
We propose a multi length scale approach to modeling recrystallization which links a dislocation model, a cell growth model and a macroscopic model. Although this methodology and linking framework will be applied to recrystallization, it is also applicable to other types of phase transformations in bulk and layered materials. Critical processes such as the dislocation structure evolution, nucleation, the evolution of crystal orientations into a preferred texture, and grain size evolution all operate at different length scales. In this paper we focus on incorporating experimental measurements of dislocation substructures, rnisorientation measurements of dislocation boundaries, and dislocation simulations into a mesoscopic model of cell growth. In particular, we show how feeding information from the dislocation model into the cell growth model can create realistic initial microstructure.
The in-situ generation of silica reinforcement in modified polydimethylsiloxane elastomers
Structure and properties of a series of modified polydimethylsiloxane (PDMS) elastomers reinforced by {ital in situ} generated silic particles were investigated. The PDMS elastomer was modified by systematically varying the molecular weight between reactive groups incorporated into the backbone. Tetraethoxysilane (TEOS) and partial hydrolyzate of TEOS were used to generate silic particles. Chemistry and phase structure of the materials were investigated by {sup 29}Si magic angle spinning nuclear magnetic resonance spectroscopy and swelling experiments.