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Development of small-bore, high-current-density railgun as testbed for study of plasma-materials interaction. Progress report for October 16,2000 - May 13, 2003

Description: The present document is a final technical report summarizing the progress made during 10/16/2000 - 05/13/2003 toward the development of a small-bore railgun with transaugmentation as a testbed for investigating plasma-materials interaction.
Date: May 14, 2003
Creator: Kim, Kyekyoon (Kevin)
Partner: UNT Libraries Government Documents Department

Cavitational Hydrothermal Oxidation: A New Remediation Process - Final Report

Description: During the past year, we have continued to make substantial scientific progress on our understanding of cavitation phenomena in aqueous media and applications of cavitation to remediation processes. Our efforts have focused on three separate areas: sonoluminescence as a probe of conditions created during cavitational collapse in aqueous media, the use of cavitation for remediation of contaminated water, and an addition of the use of ultrasound in the synthesis of novel heterogeneous catalysts for hydrodehalogenation of halocarbons under mild conditions.
Date: July 5, 2001
Creator: Suslick, K. S.
Partner: UNT Libraries Government Documents Department

Final report DOE project, ''Origins of asymmetric stress-strain response in phase transformations,'' DEFG02-93ER143993

Description: For the first time, experiments on NiTi under pressure loadings were conducted in Ref. (1). This work showed that the stress-strain response of NiTi is highly pressure sensitive and there was an asymmetry of tension and compression results. The results were obtained based on the special rig developed in (Ref. 2) by Sehitoglu and his students. Several experiments under pressure were also conducted on CuZnAl alloys with also pressure dependent response. accounted for variant-variant interaction and texture effects in the case of NiTi alloys (Ref. 3). It was found that the polycrystalline version of these materials has a strong texture due to the cold rolling process (Figure 4). Consequently, they almost behave as single crystals oriented in the [111] direction (Figure 3). We showed that if the texture effects are not accounted for the models give the incorrect trends when compared with experiments (Figure 5). Our work also showed that the evolution of the variants in tension is much more rapid compared to the compression case (Ref. 3). In the second year of the work, our attention focused exclusively on the deformation behavior of single crystals. Several key results were achieved with single crystals. Initially, we studied the role of aging treatment on tension compression asymmetry and crystal orientation dependence. It was shown that the orientation dependence of critical resolved shear stress is significant in the case of peak aged crystals while the orientation dependence decreases with overaging. A micro-mechanical model was developed to explain these trends based on the determination of the local shear stresses due to the precipitate on the 24 possible martensite variants (Figure 6). It was found that those variants that have high resolved shear stress due to external loading experience low local stresses due to the precipitate weakening the orientation dependence (Refs. 4-6). Overall the ...
Date: January 30, 2002
Creator: Sehitoglu, Huseyin
Partner: UNT Libraries Government Documents Department

Investigation of groundwater flow paths through combined inversion of strontium isotope ratios and hydraulic head data. Final report

Description: Strontium (Sr) isotope and other geochemical data were collected for groundwater samples from the Snake River Plain aquifer in the vicinity of the Idaho National Engineering and Environmental Laboratory (INEEL). These geochemical data provide strong evidence for slow and fast groundwater flow zones that had not been previously characterized. The geochemical data were combined with existing hydraulic head data in groundwater flow and transport models. These models enable quantitative extraction of flow information from the data (i.e., inversion of the data). This new approach and the implications for INEEL environmental activities will be reported in two journal articles. One submitted recently and a second in preparation.
Date: December 4, 1999
Creator: Johnson, Thomas M.
Partner: UNT Libraries Government Documents Department

Oxide film microstructure: the link between surface preparation processes and strength/durability of adhesively bonded aluminum. Final report

Description: Strength and durability of adhesive bonding of aluminum alloys structures are intrinsically determined by the surface microstructures and interfacial failure micromechanisms. The current project presents a multidisciplinary approach to addressing critical issues controlling the strength and durability of adhesive bonds of aluminum alloys. Three main thrust areas have been pursued: surface treatment technology development to achieve desirable surface microstructures; relationship between surface structure and properties of adhesive bonds; and failure mechanisms of adhesively bonded components.
Date: November 30, 2000
Creator: Hsia, K. Jimmy; Pearlstein, Arne J.; Scheeline, Alexander & Shang, Jian Ku
Partner: UNT Libraries Government Documents Department

A New Framework for Adaptive Sampling and Analysis During Long- Term Monitoring and Remedial Action Management

Description: The Argonne team has gathered available data on monitoring wells and measured hydraulic heads from the Argonne 317/319 site and sent it to UIUC. Xiaodong Li, a research assistant supported by the project, has reviewed the data and is beginning to fit spatiotemporal statistical models to it. Another research assistant, Yonas Demissie, has gotten the site's Modflow model working and is developing a transport model that will be used to generate artificial data. Abhishek Singh, a third research assistant supported by the project, has performed a literature review on inverse modeling and is receiving training on the software that will be used in this project (D2K). He has also created two models of user preferences and successfully implemented them with an interactive genetic algorithm on test functions. Meghna Babbar, the fourth research assistant supported by the project, has created an interactive genetic algorithm code and initial user interface in D2K. Gayathri Gopalakrishnan, the last research assistant who is partially supported by the project, has collected and analyzed data from the phytoremediation systems at the 317/319 site. She has found good correlations between concentrations in the ground water and in branches of the trees, which indicates excellent promise for using the trees as cost-effective long-term monitoring of the contaminants.
Date: June 1, 2003
Creator: Minsker, Barbara
Partner: UNT Libraries Government Documents Department

Nonlinear Dynamics of Parametrically Excited Gyroscopic Systems

Description: The primary objective of this project is to determine how some of the powerful geometric methods of dynamical systems can be applied to study nonlinear gyroscopic systems. We proposed to develop techniques to predict local and global behavior and instability mechanisms and to analyze the interactions between noise, stability, and nonlinearities inherent in gyroscopic systems. In order to obtain these results we use the method of normal forms, global bifurcation techniques, and various other dynamical systems tools.
Date: June 1, 2001
Creator: Namachchivaya, N. S.
Partner: UNT Libraries Government Documents Department

Improvements, Evaluation, and Application of 1D Vetem Inversion and Development and Application of 3D Vetem Inversion to Waste Pits at The Idaho National Engineering and Environmental Laboratory

Description: The project aim was the improvement, evaluation, and application of one dimensional (1D) inversion and development and application of three dimensional (3D) inversion to processing of data collected at waste pits at the Idaho National Engineering and Environmental Laboratory. The inversion methods were intended mainly for the Very Early Time Electromagnetic (VETEM) system which was designed to improve the state-of-the-art of electromagnetic imaging of the shallow (0 to about 5m) subsurface through electrically conductive soils.
Date: October 27, 2004
Creator: Chew, Weng Cho
Partner: UNT Libraries Government Documents Department

Investigation of Pore Scale Processes That Affect Soil Vapor Extraction

Description: Dense nonaqueous phase liquid (DNAPL) contamination in the vadose zone is a significant problem at Department of Energy sites. Soil vapor extraction (SVE) is commonly used to remediate DNAPLs from the vadose zone. In most cases, a period of high recovery has been followed by a sustained period of low recovery. This behavior has been attributed to multiple processes including slow interphase mass transfer, retarded vapor phase transport, and diffusion from unswept zones of low permeability. Prior attempts to uncouple and quantify these processes have relied on column experiments, where the effluent concentration was monitored under different conditions in an effort to quantify the contributions from a single process. In real porous media these processes occur simultaneously and are inter-related. Further, the contribution from each of these processes varies at the pore scale and with time. This research aims to determine the pore-scale processes that limit the removal of DNAPL components in heterogeneous porous media during SVE. The specific objectives are to: (1) determine the effect of unswept zones on DNAPL removal during SVE, (2) determine the effect of retarded vapor phase transport on DNAPL removal during SVE, and (3) determine the effect of interphase mass transfer on DNAPL removal during SVE, all as a function of changing moisture and DNAPL content. To fulfill these objectives we propose to use magnetic resonance imaging (MRI) to observe and quantify the location and size of individual pores containing DNAPL, water, and vapor in flow through columns filled with model and natural sediments. Imaging results will be used in conjunction with modeling techniques to develop spatially and temporally dependent constitutive relations that describe the transient distribution of phases inside a column experiment. This work will lead to improved models that will allow decision makers to better assess the risk associated with vadose zone ...
Date: June 24, 2004
Creator: Valocchi, Albert J.; Werth, Charles J. & Webb, Andrew G.
Partner: UNT Libraries Government Documents Department

Final Report: Investigation of Saturated Degenerate Four-Wave Mixing Spectroscopy For Quantitative Concentration Measurements

Description: Our research efforts over the last few years have focused on the development of strategies for the quantitative application of DFWM and PS in flame environments. We have developed, validated, and applied a theoretical methodology based on direct numerical integration (DNI) of the time-dependent density matrix equations for analysis of the physics of the DFWM and PS processes. The incorporation of the Zeeman state structure of the energy levels of the radiative transitions has allowed us to investigate the physics of the PS process and polarization effects in DFWM. Our research effort has focused mainly on the moderate saturation regime, with laser pulse lengths significantly greater than characteristic collisional times, and with the assumption of monochromatic lasers. Recently, we have completed a study of multi-axial-mode laser effects of homogeneously broadened PS.
Date: March 20, 2001
Creator: Lucht, R. P.
Partner: UNT Libraries Government Documents Department

Experimental and Theoretical Analysis of Flashing Instability for Next Generation Natural Circulation Reactors

Description: The project had four parts: (1) Modeling and simulation of nonlinear dynamics in forced BWRs using reduced order models; (2) Modeling and simulation of nonlinear dynamics in natural circulation BWRs using reduced order models; (3) Comparison of results with those obtained using large scale system codes; and (4) Experiments to investigate natural circulation flashing phenomenon.
Date: May 13, 2005
Creator: Zboray, Robert; de Kruijf, Wilhelmus J. M.; Hagen, Tim H.J.J. van der & Rizwan-uddin
Partner: UNT Libraries Government Documents Department

Final Technical Report EMSP 70045 Investigation of Pore Scale Processes That Affect Soil Vapor Extraction

Description: Dense nonaqueous phase liquid (DNAPL) contamination in the vadose zone is a significant problem at Department of Energy sites. Soil vapor extraction (SVE) is commonly used to remediate DNAPLs from the vadose zone. In most cases, a period of high recovery has been followed by a sustained period of low recovery. This behavior has been attributed to multiple processes including slow interphase mass transfer, retarded vapor phase transport, and diffusion from unswept zones of low permeability. This research project used a combination of laboratory experimentation and mathematical modeling to determine how these various processes interact to limit the removal of DNAPL components in heterogeneous porous media during SVE. Our results were applied to scenarios typical of the carbon tetrachloride spill zone at the Hanford Site. Our results indicate that: (a) the initial distribution of the spilled DNAPL (i.e., the spill-zone architecture) has a major influence upon the performance of any subsequent SVE operations; (b) while the pattern of higher and lower conductivity soil zones has an important impact upon spill zone architecture, soil moisture distribution plays an even larger role when there are large quantities of co-disposed waste-water (as in the Hanford scenario); (c) depending upon soil moisture dynamics, liquid DNAPL that is trapped by surrounding water is extremely difficult to remove by SVE; (d) natural barometric pumping can remove a large amount of the initial DNAPL mass for spills occurring close to the land surface, and hence the initial spilled inventory will be over-estimated if this process is neglected.
Date: December 10, 2004
Creator: Valocchi, Albert J.; Werth, Charles W. & Webb, Andrew W.
Partner: UNT Libraries Government Documents Department

Development of a Two-Phase Model for the Hot Deformation of Highly-Alloyed Aluminum

Description: Conventional processing methods for highly alloyed aluminum consist of ingot casting, followed by hot rolling and thermal treatments. Defects result in lost productivity and wasted energy through the need to remelt and reprocess the material. This research centers on developing a fundamental understanding for deformation of wrought 705X series alloys, a key alloy system used in structural airframe applications. The development of damage at grain boundaries is characterized through a novel test that provides initiation of failure while preserving a controlled deformation response. Data from these mechanical tests are linked to computer simulations of the hot rolling process through a critical measure of damage. Transmission electron microscopy provides fundamental insight into deformation at these high working temperatures, and--in a novel link between microscale and macroscale response--the evolution of microstructure (crystallographic orientation) provides feedback for tuning of friction in the hot rolling process. The key product of this research is a modeling framework for the analysis of industrial hot rolling.
Date: October 31, 2005
Creator: Beaudoin, A. J.; Dantzig, J. A.; Robertson, I. M.; Gore, B. E.; Harnish, S. F. & Padilla, H. A.
Partner: UNT Libraries Government Documents Department

Determining the mechanical constitutive properties of metals as a function of strain rate and temperature: A combined experimental and modeling approach

Description: OAK-135 Development and validation of constitutive models for polycrystalline materials subjected to high strain rate loading over a range of temperatures are needed to predict the response of engineering materials to in-service type conditions (foreign object damage, high-strain rate forging, high-speed sheet forming, deformation behavior during forming, response to extreme conditions, etc.). To account accurately for the complex effects that can occur during extreme and variable loading conditions, requires significant and detailed computational and modeling efforts. These efforts must be closely coupled with precise and targeted experimental measurements that not only verify the predictions of the models, but also provide input about the fundamental processes responsible for the macroscopic response. Achieving this coupling between modeling and experimentation is the guiding principle of this program. Specifically, this program seeks to bridge the length scale between discrete dislocation interactions with grain boundaries and continuum models for polycrystalline plasticity. Achieving this goal requires incorporating these complex dislocation-interface interactions into the well-defined behavior of single crystals. Despite the widespread study of metal plasticity, this aspect is not well understood for simple loading conditions, let alone extreme ones. Our experimental approach includes determining the high-strain rate response as a function of strain and temperature with post-mortem characterization of the microstructure, quasi-static testing of pre-deformed material, and direct observation of the dislocation behavior during reloading by using the in situ transmission electron microscope deformation technique. These experiments will provide the basis for development and validation of physically-based constitutive models, which will include dislocation-grain boundary interactions for polycrystalline systems. One aspect of the program will involve the dire ct observation of specific mechanisms of micro-plasticity, as these will indicate the boundary value problem that should be addressed. This focus on the pre-yield region in the quasi-static effort (the elasto-plastic transition) is also a tractable one from an ...
Date: January 5, 2004
Creator: Robertson, I. M.; Beaudoin, A. & Lambros, J.
Partner: UNT Libraries Government Documents Department

Drop Dynamics and Speciation in Isolation of Metals from Liquid Wastes by Reactive Scavenging

Description: Computational and experimental studies of the motion and dynamics of liquid drops in gas flows were conducted with relevance to reactive scavenging of metals from atomized liquid waste. Navier-Stoke's computations of deformable drops revealed a range of conditions from which prolate drops are expected, and showed how frajectiones of deformable drops undergoing deceleration can be computed. Experimental work focused on development of emission fluorescence, and scattering diagnostics. The instrument developed was used to image drop shapes, soot, and nonaxisymmetric departures from steady flow in a 22kw combustor
Date: August 30, 2002
Creator: Pearlstein, Arne J. & Scheeline, Alexander
Partner: UNT Libraries Government Documents Department

Modeling and Thermal Performance Evaluation of Porous Curd Layers in Sub-Cooled Boiling Region of PWRs and Effects of Sub-Cooled Nucleate Boiling on Anomalous Porous Crud Deposition on Fuel Pin Surfaces

Description: A significant number of current PWRs around the world are experiencing anomalous crud deposition in the sub-cooled region of the core, resulting in an axial power shift or Axial Offset Anomaly (AOA), a condition that continues to elude prediction of occurrence and thermal/neutronic performance. This creates an operational difficulty of not being able to accurately determine power safety margin. In some cases this condition has required power ''down rating'' by as much as thirty percent and the concomitant considerable loss of revenue for the utility. This study examines two aspects of the issue: thermal performance of crud layer and effect of sub-cooled nucleate boiling on the solute concentration and its influence on initiation of crud deposition/formation on fuel pin surface.
Date: June 27, 2005
Creator: Jones, Barclay
Partner: UNT Libraries Government Documents Department

A New Framework for Adptive Sampling and Analysis During Long-Term Monitoring and Remedial Action Management

Description: Yonas Demissie, a research assistant supported by the project, has successfully created artificial data and assimilated it into coupled Modflow and artificial neural network models. His initial findings show that the neural networks help correct errors in the Modflow models. Abhishek Singh has used test cases from the literature to show that performing model calibration with an interactive genetic algorithm results in significantly improved parameter values. Meghna Babbar, the third research assistant supported by the project, has found similar results when applying an interactive genetic algorithms to long-term monitoring design. She has also developed new types of interactive genetic algorithms that significantly improve performance. Gayathri Gopalakrishnan, the last research assistant who is partially supported by the project, has shown that sampling branches of phytoremediation trees is an accurate approach to estimating soil and groundwater contaminations in areas surrounding the trees at the Argonne 317/319 site.
Date: June 1, 2005
Creator: Minsker, Barbara
Partner: UNT Libraries Government Documents Department

Novel Chemical Strategies for Labeling Small Molecule Ligands for Androgen, Progestin, and Peroxisome Proliferator-Activated Receptors for Imaging Prostate and Breast Cancer and the Heart

Description: Summary of Progress The specific aims of this project can be summarized as follows: • Aim 1: Prepare and evaluate radiolabeled ligands for the peroxisome proliferator-activated receptor  (PPAR), a new nuclear hormone receptor target for tumor imaging and hormone therapy. • Aim 2: Prepare steroids labeled with a cyclopentadienyl tricarbonyl technetium or rhenium unit. • Aim 3: Prepare and evaluate other organometallic systems of novel design as ligand mimics and halogenated ligands for nuclear hormone receptor-based tumor imaging. As is described in detail below, we made excellent progress on all three of these aims; the highlights of our progress are the following: • we have prepared the first fluorine-18 labeled analogs of ligands for the PPAR receptor and used these in tissue distribution studies in rats • we have developed three new methods for the synthesis of cyclopentadienyltricarbonyl rhenium and technetium (CpRe(CO)3 and CpTc(CO)3) systems and we have adapted these to the synthesis of steroids labeled with these metals, as well as ligands for other receptor systems • we have prepared a number of fluorine-18 labeled steroidal and non-steroidal androgens and measured their tissue distribution in rats • we have prepared iodine and bromine-labeled progestins with high progesterone receptor binding affinity • we have prepared inorganic metal tricarbonyl complexes and steroid receptor ligands in which the metal tricarbonyl unit is an integral part off the ligand core.
Date: April 19, 2007
Creator: Katzenellenbogen, John, A.
Partner: UNT Libraries Government Documents Department