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Detailed Study of the {sup 3}He Nucleus through Response function Separations at High Momentum Transfer

Description: In order to further our understanding of the few body system, a new series of measurements on the reaction {sup 3}He(e,e'p) has been made at Jefferson Lab. Making use of beam energies as high as 4.8{approx}GeV and of the two high resolution spectrometers in Hall A, kinematics which were previously unattainable have been investigated. In this paper the first preliminary results of this experiment will be presented.
Date: December 1, 2002
Creator: Higinbotham, Douglas W.
Partner: UNT Libraries Government Documents Department
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Measurement of Inclusive Spin Structure Functions of the Deuteron with CLAS

Description: We report the results of a new measurement of spin structure functions of the deuteron in the region of moderate momentum transfer (Q{sup 2} = 0.27 -- 1.3 (GeV/c){sup 2}) and final hadronic state mass in the nucleon resonance region (W = 1.08 -- 2.0 GeV). We scattered a 2.5 GeV polarized continuous electron beam at Jefferson Lab off a dynamically polarized cryogenic solid state target ({sup 15}ND{sub 3}) and detected the scattered electrons with the CEBAF Large Acceptance Spectrometer (CLAS). From our data, we extract the longitudinal double spin asymmetry A{sub {parallel}} and the spin structure function g{sub 1}{sup d}. Our data are generally in reasonable agreement with existing data from SLAC where they overlap, and they represent a substantial improvement in statistical precision. We compare our results with expectations for resonance asymmetries and extrapolated deep inelastic scaling results. Finally, we evaluate the first moment of the structure function g{sub 1}{sup d} and study its approach to both the deep inelastic limit at large Q{sup 2} and to the Gerasimov-Drell-Hearn sum rule at the real photon limit (Q{sup 2}-0). We find that the first moment varies rapidly in the Q{sup 2} range of our experiment and crosses zero at Q{sup 2} between 0.5 and 0.8 (GeV/c){sup 2}, indicating the importance of the {Delta} resonance at these momentum transfers.
Date: December 1, 2002
Creator: Yun, J. & Collaboration, CLAS
Partner: UNT Libraries Government Documents Department
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Review of Air Flow Measurement Techniques

Description: Airflow measurement techniques are necessary to determine the most basic of indoor air quality questions: ''Is there enough fresh air to provide a healthy environment for the occupants of the building?'' This paper outlines airflow measurement techniques, but it does not make recommendations for techniques that should be used. The airflows that will be discussed are those within a room or zone, those between rooms or zones, such as through doorways (open or closed) or passive vents, those between the building and outdoors, and those through mechanical air distribution systems. Techniques that are highlighted include particle streak velocimetry, hot wire anemometry, fan pressurization (measuring flow at a given pressure), tracer gas, acoustic methods for leak size determination, the Delta Q test to determine duct leakage flows, and flow hood measurements. Because tracer gas techniques are widely used to measure airflow, this topic is broken down into sections as follows: decay, pulse injection, constant injection, constant concentration, passive sampling, and single and multiple gas measurements for multiple zones.
Date: December 1, 2002
Creator: McWilliams, Jennifer
Partner: UNT Libraries Government Documents Department
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Assessment of Salmonids and their Habitat Conditions in the Walla Walla River Basin within Washington, 2001 Annual Report.

Description: Concerns about the decline of native salmon and trout populations have increased among natural resource managers and the public in recent years. As a result, a multitude of initiatives have been implemented at the local, state, and federal government levels. These initiatives include management plans and actions intended to protect and restore salmonid fishes and their habitats. In 1998 bull trout (Salvelinus confluentus) were listed under the Endangered Species Act (ESA), as ''Threatened'', for the Walla Walla River and its tributaries. Steelhead (Oncorhynchus mykiss) were listed as ''Threatened'' in 1999 for the mid-Columbia River and its tributaries. These ESA listings emphasize the need for information about these threatened salmonid populations and their habitats. The Washington Department of Fish and Wildlife (WDFW) is entrusted with ''the preservation, protection, and perpetuation of fish and wildlife....[and to] maximize public recreational or commercial opportunities without impairing the supply of fish and wildlife (WAC 77.12.010).'' In consideration of this mandate, the WDFW submitted a proposal in December 1997 to the Bonneville Power Administration (BPA) for a study to assess salmonid distribution, relative abundance, genetics, and the condition of salmonid habitats in the Walla Walla River basin. The primary purposes of this project are to collect baseline biological and habitat data, to identify major data gaps, and to draw conclusions whenever possible. The study reported herein details the findings of the 2001 field season (March to November, 2001).
Date: December 1, 2002
Creator: Mendel, Glen Wesley; Trump, Jeremy & Karl, David
Partner: UNT Libraries Government Documents Department
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Small-Scale Multiaxial Deformation Experiments on Solder for High-Fidelity Model Development

Description: Solder in our applications is used for more than just an electrical connection. It also serves as the load bearing structures for some electronic components. Thus the mechanical properties of solder interconnects were studied to ensure the reliability of electronic assemblies. Studies include deformation and failure associated with size effect, deformation mechanism map, and microstructural coarsening. Results show that tensile stress-strain behavior is size dependent. Small solder specimens do not follow bulk material properties when the cross-sectional area of the gage section is less than 0.1 mm{sup 2}. The effect of microstructural size is found to be minimal, based on two averaged Pb-rich phase sizes, 2 and 4 {micro}m. From multiaxial creep experiments at room temperature and 100 C, the activation energy and stress exponent are consistent with published values for Region-I creep behavior. The creep conditions explored in this study establish the aspects of a multiaxial deformation mechanism map that are typical of normal stockpile conditions. The Von Mises equivalent stress appears to work well for various loading modes. The coarsening phenomenon of eutectic solder is still not very clear. It requires a large number of observations to mitigate the extensive variability in both starting microstructure and response. From isothermal torsional fatigue at 10{sup -4} and 10{sup -5} s{sup -1}, there is no correlation between the initial phase size and the magnitude of accumulated strain experienced by the specimen. In creep specimens, localized coarsening is observed at the failed region for some loading conditions, predominantly under pure shear.
Date: December 1, 2002
Creator: Lu, Wei-Yang
Partner: UNT Libraries Government Documents Department
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2001 environmental monitoring report for the Bettis Atomic Power Laboratory, West Mifflin Site

Description: The 2001 results for the Bettis-Pittsburgh radiological and nonradiological environmental monitoring programs are presented. The results demonstrate that the existing procedures ensured that releases to the environment during 2001 were in accordance with applicable Federal, State, County, and local regulations. Evaluation of the environmental data indicates that current operations at the Site continue to have no adverse effect on human health and the quality of the environment. A conservative assessment of radiation exposure to the general public as a result of Site operations demonstrates that the dose received by any member of the public was well below the most restrictive dose limits established by the Environmental Protection Agency, the Nuclear Regulatory Commission, and the U.S. Department of Energy. A risk assessment of potentially exposed populations to chemical residues in the environment at the Site demonstrates that any potential risk posed by these residues is much less than the risks encountered in normal everyday life.
Date: December 1, 2002
Partner: UNT Libraries Government Documents Department
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Recovery and Sequestration of co2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Progress Report: July-September 2002

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 July to 30 September 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.
Date: December 1, 2002
Creator: Nakamura, T.; Olaizola, Miguel & Masutani, Stephen M.
Partner: UNT Libraries Government Documents Department
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Use of Intense Ion Beams for Surface Modification and Creation of New Materials

Description: We have conducted surface treatment and alloying experiments with Al, Fe, and Ti-based metals on the RHEPP-1 accelerator (0.8 MV, 20 W, 80 ns FHWM, up to 1 Hz repetition rate) at Sandia National Laboratories. Ions are generated by the MAP gas-breakdown active anode, which can yield a number of different beam species including H, N, and C, depending upon the injected gas. Beams of intense pulsed high-power ion beams have been used to produce surface modification by changes in microstructure caused by rapid heating and cooling of the surface. Increase of beam power leads to ablation of a target surface, and redeposition of ablated material onto a separate substrate. Experiments are described in which ion beams are used in an attempt to increase high-voltage breakdown of a treated surface. Surface alloying of coated Pt and Hf layers is also described. This mixing of a previously deposited thin-film layer into a Ti-alloy substrate leads to significantly enhanced surface wear durability, compared to either untreated Ti-alloy alone, or the Ti alloy alone treated with the ion beam. Thin-film layers have been produced from a number of target materials. Films of fine-grain Pt and Er are described, and are compared to conventionally formed films. First attempts to form high-dielectric constant BaTiO{sub 3} are described.
Date: December 1, 2002
Creator: RENK, TIMOTHY J.; PROVENCIO, PAULA P.; CLEM, PAUL G.; PRASAD, SOMURI V. & THOMPSON, M.O.
Partner: UNT Libraries Government Documents Department
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Continuum Definitions for Stress in Atomistic simulation

Description: This report is a collection of documents written by the group members of the Engineering Sciences Research Foundation (ESRF), Laboratory Directed Research and Development (LDRD) project titled ''A Robust, Coupled Approach to Atomistic-Continuum Simulation''. An essential requirement of this project is to develop definitions for continuum quantities that can be evaluated locally within an atomistic region. We are developing physical measures of stress, deformation and temperature that are calculable in an atomistic simulation and have well-defined meanings when evaluated in the continuum limit. During the course of FY02, we reviewed many articles presenting the use of definitions of stress in atomistic simulation. The key articles were identified and summarized via internal documents.
Date: December 1, 2002
Creator: Zimmerman, Jonathan A.
Partner: UNT Libraries Government Documents Department
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Bias and self-bias of magnetic macroparticle filters for cathodic arc plasmas

Description: Curved magnetic filters are often used for the removal of macroparticles from cathodic arc plasmas. This study addresses the need to further reduce losses and improving plasma throughput. The central figure of merit is the system coefficient Kappa defined as filtered ion current normalized by the plasma-producing arc current. The coefficient Kappa is investigated as a function of DC and pulsed magnetic field operation, magnetic field strength, external electric bias, and arc amplitude. It increases with positive filter bias but saturates at about 15 V for relatively low magnetic field ({approx}10 mT), whereas stronger magnetic fields lead to higher Kappa with saturation at about 25 V. Further increase of positive bias reduces Kappa. These findings are true for both pulsed and DC filters. Bias of pulsed filters has been realized using the voltage drop across a self-bias resistor, eliminating the need for a separate bias circuit. Almost 100 A of filtered copper ions have been obtained in pulse d mode, corresponding to Kappa approximately equal to 0.04. The results are interpreted by a simplified potential trough model.
Date: December 1, 2002
Creator: Byon, Eungsun & Anders, Andre
Partner: UNT Libraries Government Documents Department
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Development of a 400 Level 3C Clamped Downhole Seismic Receiver Array for 3D Borehole Seismic Imaging of Gas Reservoirs, Quarterly Report: July 1 - September 30, 2002

Description: Borehole seismology is the highest resolution geophysical imaging technique available today to the oil and gas industry for characterization and monitoring of oil and gas reservoirs. However, the industry's ability to economically do high resolution 3D imaging of deep and complex gas reservoirs using borehole seismology is currently frustrated by the lack of the acquisition technology necessary to record the large volumes of the high frequency, high signal-to-noise-ratio borehole seismic data needed to do 3D imaging. This project takes direct aim at this shortcoming by developing a 400 level 3C clamped downhole seismic receiver array, and accompanying software, for borehole seismic 3D imaging. This large borehole seismic array will remove the technical acquisition barrier for recording the necessary volumes of data to do high resolution 3D VSP or 3D cross well seismic imaging. 3D VSP and long range Cross-Well Seismology (CWS) are two of the borehole seismic techniques that will allow the Gas industry to take the next step in their quest for higher resolution images of the gas reservoirs for the purpose of improving the recovery of the natural gas resources. Today only a fraction of the original Oil or Gas in place is produced when reservoirs are considered depleted. This is primarily due to our lack of understanding of the detailed compartmentalization of the oil and gas reservoirs. The 400 level 3C borehole seismic receiver array will allow for the economic use of 3D borehole seismic imaging for reservoir characterization and monitoring by allowing the economic recording of the required large data volumes that have a sufficiently dense spatial sampling. By using 3C surface seismic or 3C borehole seismic sources the 400 level receiver array will furthermore allow 3D reservoir imaging using 9C data. The 9C borehole seismic data will provide P, SH and SV information for imaging …
Date: December 1, 2002
Creator: Paulsson, Bjorn N. P.
Partner: UNT Libraries Government Documents Department
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Geology of the Western Part of Los Alamos National Laboratory (TA-3 to TA-16), Rio Grande Rift, New Mexico

Description: We present data that elucidate the stratigraphy, geomorphology, and structure in the western part of Los Alamos National Laboratory between Technical Areas 3 and 16 (TA-3 and TA-16). Data include those gathered by geologic mapping of surficial, post-Bandelier Tuff strata, conventional and high-precision geologic mapping and geochemical analysis of cooling units within the Bandelier Tuff, logging of boreholes and a gas pipeline trench, and structural analysis using profiles, cross sections, structure contour maps, and stereographic projections. This work contributes to an improved understanding of the paleoseismic and geomorphic history of the area, which will aid in future seismic hazard evaluations and other investigations. The study area lies at the base of the main, 120-m (400-ft) high escarpment formed by the Pajarito fault, an active fault of the Rio Grande rift that bounds Los Alamos National Laboratory on the west. Subsidiary fracturing, faulting, and folding associated with the Pajarito fault zone extends at least 1,500 m (5,000 ft) to the east of the main Pajarito fault escarpment. Stratigraphic units in the study area include upper units of the Tshirege Member of the early Pleistocene Bandelier Tuff, early Pleistocene alluvial fan deposits that predate incision of canyons on this part of the Pajarito Plateau, and younger Pleistocene and Holocene alluvium and colluvium that postdate drainage incision. We discriminate four sets of structures in the area between TA-3 and TA-16: (a) north-striking faults and folds that mark the main zone of deformation, including a graben in the central part of the study area; (b) north-northwest-striking fractures and rare faults that bound the eastern side of the principal zone of deformation and may be the surface expression of deep-seated faulting; (c) rare northeast-striking structures near the northern limit of the area associated with the southern end of the Rendija Canyon fault; and (d) several …
Date: December 1, 2002
Creator: C.J.Lewis; A.Lavine; S.L.Reneau; J.N.Gardner; R.Channell & C.W.Criswell
Partner: UNT Libraries Government Documents Department
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The Confederated Tribes of the Warm Springs Indian Reservation of Oregon John Day Basin Office : Watershed Restoration Projects : Annual Report, 2001.

Description: The John Day River is the nation's second longest free-flowing river in the contiguous United States, which is entirely unsupplemented for it's runs of anadromous fish. Located in eastern Oregon, the John Day Basin drains over 8,000 square miles, is Oregon's fourth largest drainage basin, and the basin incorporates portions of eleven counties. Originating in the Strawberry Mountains near Prairie City, the mainstem John Day River flows 284 miles in a northwesterly direction entering the Columbia River approximately four miles upstream of the John Day dam. With wild runs of spring Chinook salmon, summer steelhead, westslope cutthroat, and redband and bull trout, the John Day system is truly a basin with national significance. The Majority of the John Day Basin was ceded to the Federal government in 1855 by the Confederated Tribes of the Warm Springs Reservation of Oregon (Tribes). In 1997, the Tribes established an office in John Day to coordinate basin restoration projects, monitoring, planning, and other watershed restoration activities on private and public lands. Once established, the John Day Basin Office (JDBO) formed a partnership with the Grant Soil and Water Conservation District (GSWCD), also located in John Day, who subcontracts the majority of the construction implementation activities for these restoration projects from the JDBO. The GSWCD completes the landowner contact, preliminary planning, engineering design, permitting, construction contracting, and construction implementation phases of most projects. The JDBO completes the planning, grant solicitation/defense, environmental compliance, administrative contracting, monitoring, and reporting portion of the program. Most phases of project planning, implementation, and monitoring are coordinated with the private landowners and basin agencies, such as the Oregon Department of Fish and Wildlife and Oregon Water Resources Department. In 2001, the JDBO and GSWCD continued their successful partnership between the two agencies and basin landowners to implement an additional ten (10) …
Date: December 1, 2002
Creator: Office., Confederated Tribes of the Warm Springs Reservation of Oregon. John Day Basin
Partner: UNT Libraries Government Documents Department
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Ecological Monitoring and Compliance Program Fiscal Year 2002 Report

Description: The Ecological Monitoring and Compliance program, funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office, monitors the ecosystem of the Nevada Test Site (NTS) and ensures compliance with laws and regulations pertaining to NTS biota. This report summarizes the program's activities conducted by Bechtel Nevada (BN) during fiscal year 2002. Program activities included: (1) biological surveys at proposed construction sites, (2) desert tortoise compliance, (3) ecosystem mapping and data management, (4) sensitive species and unique habitat monitoring, and (5) biological monitoring at the HAZMAT Spill Center. Biological surveys for the presence of sensitive species and important biological resources were conducted for 26 NTS projects. These projects have the potential to disturb a total of 374 acres. Thirteen of the projects were in desert tortoise habitat, and 13.38 acres of desert tortoise habitat were disturbed. No tortoises were found in or displaced from project areas, and no tortoises were accidentally injured or killed at project areas or along paved roads. Compilation of historical wildlife data continued this year in efforts to develop faunal distribution maps for the NTS. Photographs associated with the NTS ecological landform units sampled to create the NTS vegetation maps were cataloged for future retrieval and analysis. The list of sensitive plant species for which long-term population monitoring is scheduled was revised. Six vascular plants and five mosses were added to the list. Plant density estimates from ten populations of Astragalus beatleyae were collected, and eight known populations of Eriogonum concinnum were visited to assess plant and habitat status. Minimal field monitoring of western burrowing owl burrows occurred. A report relating to the ecology of the western burrowing owl on the Nevada Test Site was prepared which summarizes four years of data collected on this species' distribution, burrow use, reproduction, activity patterns, and …
Date: December 1, 2002
Creator: Wills, C. A.
Partner: UNT Libraries Government Documents Department
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Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents

Description: Vibrational spectra can serve as chemical fingerprints for positive identification of chemical and biological warfare molecules. The required speed and sensitivity might be achieved with surface-enhanced Raman spectroscopy (SERS) using nanotextured metal surfaces. Systematic and reproducible methods for preparing metallic surfaces that maximize sensitivity have not been previously developed. This work sought to develop methods for forming high-efficiency metallic nanostructures that can be integrated with either gas or liquid-phase chem-lab-on-a-chip separation columns to provide a highly sensitive, highly selective microanalytical system for detecting current and future chem/bio agents. In addition, improved protein microchromatographic systems have been made by the creation of acrylate-based porous polymer monoliths that can serve as protein preconcentrators to reduce the optical system sensitivity required to detect and identify a particular protein, such as a bacterial toxin.
Date: December 1, 2002
Creator: ASHBY, CAROL I.; SHEPODD, TIMOTHY J.; YELTON, WILLIAM G. & MURON, DAVID J.
Partner: UNT Libraries Government Documents Department
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Kinetic Understanding of the Syngas-to-Dme Reaction System and Its Implications to Process and Economics

Description: In a single-step synthesis gas-to-dimethyl ether process, synthesis gas (or syngas, a mixture of H{sub 2} and CO) is converted into dimethyl ether (DME) in a single reactor. The three reactions involved in this process, methanol synthesis, methanol dehydration and water gas shift, form an interesting reaction network. The interplay among these three reactions results in excellent syngas conversion or reactor productivity. A fundamental understanding of this interplay helps to explain many experimental and simulation observations, to identify optimal reaction conditions, and to provide guidelines for process development. The higher syngas conversion or reactor productivity in the syngas-to-DME reaction system, compared to that in the syngas-to-methanol reaction system, is referred to as chemical synergy. This synergy exhibits a strong dependence on the composition of the reactor feed. To demonstrate the extent of this dependence, simulations with adjusted activity for each reaction were performed to reveal the relative rate of each reaction. The results show that the water gas shift reaction is the most rapid, being practically controlled by the equilibrium. Both methanol synthesis and methanol dehydration reactions are kinetically controlled. The kinetics of the dehydration reactions is greater than that of the methanol synthesis reaction in the CO-rich regime. However, the rates of these two reactions come closer as the H{sub 2} concentration in the reactor feed increases. The role of the dehydration reaction is to remove the equilibrium barrier for the methanol synthesis reaction. The role of the water gas shift reaction is more complex; it helps the kinetics of methanol dehydration by keeping the water concentration low, which in turn enhances methanol synthesis. It also readjusts the H{sub 2}:CO ratio in the reactor as the reactions proceed. In the CO-rich regime, the water gas shift reaction supplements the limiting reactant, H{sub 2}, by reacting water with CO. This …
Date: December 1, 2002
Creator: Peng, Xiang-Dong
Partner: UNT Libraries Government Documents Department
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PROTON-CONDUCTING DENSE CERAMIC MEMBRANES FOR HYDROGEN SEPARATION

Description: This project is aimed at preparation of thin membranes of a modified strontium ceramic material on porous substrates with improved hydrogen permeance. The research work conducted in this reporting period was focused on studying synthesis methods for preparation of thin thulium doped strontium cerate (SrCe{sub 0.95}Tm{sub 0.05}O{sub 3}, SCTm) membranes. The following two methods were studied in the past year: (1) polymeric-gel casting and (2) dry-pressing. The polymeric-gel casting method includes preparation of mixed metal oxide gel and coating of the gel on a macroporous alumina support. Micrometer thick SCTm films of the perovskite structure can be obtained by this method. However, the deposited films are not hermetic and it may require about 50 coatings in order to obtain gas-tight SCTm films by this method. Asymmetric SCTm membranes consisting of a thick macroporous SCTm support and a thin SCTm layer can be effectively prepared by the dry-pressing method. The membranes were prepared by pressing together a thick layer of coarse SCTm powder and a thin layer of finer SCTm powder, followed by calcination and sintering under proper conditions. The asymmetric SCTm membranes have desired phase structure and are hermetic. Hydrogen permeation flux through the SCT membranes is inversely proportional to the thickness of the dense layer of the asymmetric membranes. The results show a substantial improvement in hydrogen permeation flux by reducing the SCTm membrane thickness.
Date: December 1, 2002
Creator: Lin, Jerry Y.S.
Partner: UNT Libraries Government Documents Department
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Nanostructured Materials Integrated in Microfabricated Optical Devices

Description: This project combined nanocomposite materials with microfabricated optical device structures for the development of microsensor arrays. For the nanocomposite materials we have designed, developed, and characterized self-assembling, organic/inorganic hybrid optical sensor materials that offer highly selective, sensitive, and reversible sensing capability with unique hierarchical nanoarchitecture. Lipid bilayers and micellar polydiacetylene provided selective optical response towards metal ions (Pb(II), Hg(II)), a lectin protein (Concanavalin A), temperature, and organic solvent vapor. These materials formed as composites in silica sol-gels to impart physical protection of the self-assembled structures, provide a means for thin film surface coatings, and allow facile transport of analytes. The microoptical devices were designed and prepared with two- and four-level diffraction gratings coupled with conformal gold coatings on fused silica. The structure created a number of light reflections that illuminated multiple spots along the silica surface. These points of illumination would act as the excitation light for the fluorescence response of the sensor materials. Finally, we demonstrate an integrated device using the two-level diffraction grating coupled with the polydiacetylene/silica material.
Date: December 1, 2002
Creator: SASAKI, DARRYL Y.; LAST, JULIE A.; BONDURANT, BRUCE; WAGGONER, TINA A.; BRINKER, C. JEFFREY; KEMME, SHANALYN A. et al.
Partner: UNT Libraries Government Documents Department
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HETEROGENEOUS SHALLOW-SHELF CARBONATE BUILDUPS IN THE PARADOX BASIN, UTAH AND COLORADO: TARGETS FOR INCREASED OIL PRODUCTION AND RESERVES USING HORIZONTAL DRILLING TECHNIQUES

Description: The Paradox Basin of Utah, Colorado, Arizona, and New Mexico contains nearly 100 small oil fields producing from carbonate buildups within the Pennsylvanian (Desmoinesian) Paradox Formation. These fields typically have one to 10 wells with primary production ranging from 700,000 to 2,000,000 barrels (111,300-318,000 m{sup 3}) of oil per field and a 15 to 20 percent recovery rate. At least 200 million barrels (31.8 million m{sup 3}) of oil will not be recovered from these small fields because of inefficient recovery practices and undrained heterogeneous reservoirs. Several fields in southeastern Utah and southwestern Colorado are being evaluated as candidates for horizontal drilling and enhanced oil recovery from existing, vertical, field wells based upon geological characterization and reservoir modeling case studies. Geological characterization on a local scale is focused on reservoir heterogeneity, quality, and lateral continuity, as well as possible reservoir compartmentalization, within these fields. This study utilizes representative cores, geophysical logs, and thin sections to characterize and grade each field's potential for drilling horizontal laterals from existing development wells. The results of these studies can be applied to similar fields elsewhere in the Paradox Basin and the Rocky Mountain region, the Michigan and Illinois Basins, and the Midcontinent region. This report covers research activities for the first half of the third project year (April 6 through October 5, 2002). This work included capillary pressure/mercury injection analysis, scanning electron microscopy, and pore casting on selected samples from Cherokee and Bug fields, Utah. The diagenetic fabrics and porosity types found at these fields are indicators of reservoir flow capacity, storage capacity, and potential for enhanced oil recovery via horizontal drilling. The reservoir quality of Cherokee and Bug fields has been affected by multiple generations of dissolution, anhydrite plugging, and various types of cementation which act as barriers or baffles to fluid flow. …
Date: December 1, 2002
Creator: Chidsey, Thomas C. Jr.
Partner: UNT Libraries Government Documents Department
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Measurement of Beam-Spin Asymmetries for Deep Inelastic pi{sup +} Electroproduction

Description: We report the first evidence for a non-zero beam-spin azimuthal asymmetry in the electroproduction of positive pions in the deep-inelastic region. Data have been obtained using a polarized electron beam of 4.3 GeV and with the CLAS detector at the Thomas Jefferson National Accelerator Facility (JLab). The amplitude of the sin phi modulation increases with the momentum of the pion relative to the virtual photon, z, with an average amplitude of 0.038+/-0.005+/-0.003 for 0.5<z<0.8 range.
Date: December 1, 2002
Creator: Avakian, H.; Burkert, Volker D.; Elouadrhiri, Latifa & al., et.
Partner: UNT Libraries Government Documents Department
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Impact of beam transport method on chamber and driver design for heavy ion inertial fusion energy

Description: In heavy ion inertial fusion energy systems, intense beams of ions must be transported from the exit of the final focus magnet system through the target chamber to hit millimeter spot sizes on the target. In this paper, we examine three different modes of beam propagation: neutralized ballistic transport, assisted pinched transport, and self-pinched transport. The status of our understanding of these three modes is summarized, and the constraints imposed by beam propagation upon the chamber environment, as well as their compatibility with various chamber and target concepts, are considered. We conclude that, on the basis of our present understanding, there is a reasonable range of parameter space where beams can propagate in thick-liquid wall, wetted-wall, and dry-wall chambers.
Date: December 1, 2002
Creator: Rose, D. V.; Welch, D. R.; Olson, C. L.; Yu, S. S.; Neff, S. & Sharp, W. M.
Partner: UNT Libraries Government Documents Department
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What are Spent Nuclear Fuel and High-Level Radioactive Waste?

Description: Spent nuclear fuel and high-level radioactive waste are materials from nuclear power plants and government defense programs. These materials contain highly radioactive elements, such as cesium, strontium, technetium, and neptunium. Some of these elements will remain radioactive for a few years, while others will be radioactive for millions of years. Exposure to such radioactive materials can cause human health problems. Scientists worldwide agree that the safest way to manage these materials is to dispose of them deep underground in what is called a geologic repository.
Date: December 1, 2002
Creator: United States. Department of Energy.
Partner: UNT Libraries Government Documents Department
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