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DATA MINING AT THE NEBRASKA OIL & GAS COMMISSION

Description: The purpose of this study of the hearing records is to identify factors that are likely to impact the performance of a waterflood in the Nebraska panhandle. The records consisted of 140 cases. Most of the hearings were held prior to 1980. Many of the records were incomplete, and data believed to be key to estimating waterflood performance such as Dykstra-Parson permeability distribution or relative permeability were absent. New techniques were applied to analyze the sparse, incomplete dataset. When information is available, but not clearly understood, new computational intelligence tools can decipher correlations in the dataset. Fuzzy ranking and neural networks were the tools used to estimate secondary recovery from the Cliff Farms Unit. The hearing records include 30 descriptive entries that could influence the success or failure of a waterflood. Success or failure is defined by the ratio of secondary to primary oil recovery (S/P). Primary recovery is defined as cumulative oil produced at the time of the hearing and secondary recovery is defined as the oil produced since the hearing date. Fuzzy ranking was used to prioritize the relevance of 6 parameters on the outcome of the proposed waterflood. The 6 parameters were universally available in 44 of the case hearings. These 44 cases serve as the database used to correlate the following 6 inputs with the respective S/P. (1) Cumulative Water oil ratio, bbl/bbl; (2) Cumulative Gas oil ratio, mcf/bbl; (3) Unit area, acres; (4) Average Porosity, %; (5) Average Permeability, md; (6) Initial bottom hole pressure, psi. A 6-3-1 architecture describes the neural network used to develop a correlation between the 6 input parameters and their respective S/P. The network trained to a 85% correlation coefficient. The predicted Cliff Farms Unit S/P is 0.315 or secondary recovery is expected to be 102,700 bbl.
Date: May 1, 2001
Creator: Weber, James R.
Partner: UNT Libraries Government Documents Department

Efficiency Improvement of Crystalline Solar Cells: Final Subcontract Report; October 2001--December 2004

Description: The approach in this subcontract was to use unique analytical tools available at Berkeley to perform systematic fundamental physical studies of the distribution and chemical state of metal clusters in a variety of multicrystalline silicon materials. Two analytical techniques were essential for the success of this project. The total metal concentration in the areas of multicrystalline silicon with high and low lifetime was determined by neutron activation analysis, a technique that involves irradiation of a sample with neutrons in a nuclear reactor and analysis of its residual radioactivity. The distribution and chemical state of metal clusters was characterized by synchrotron radiation-based X-ray microscopes available at the Advanced Light Source (Beamlines 10.3.1 and 10.3.2) at Lawrence Berkeley National Laboratory and Advanced Photon Source (Beamlines 2-ID-D and 20-ID-B) at Argonne National Laboratory.
Date: February 1, 2005
Creator: Weber, E. R.
Partner: UNT Libraries Government Documents Department

Nondestructive examination development and demonstration plan

Description: Nondestructive examination (NDE) of waste matrices using penetrating radiation is by nature very subjective. Two candidate systems of examination have been identified for use in WRAP 1. This test plan describes a method for a comparative evaluation of different x-ray examination systems and techniques.
Date: August 21, 1991
Creator: Weber, J. R.
Partner: UNT Libraries Government Documents Department

Impurity Precipitation, Dissolution, Gettering and Passivation in PV Silicon: Final Technical Report, 30 January 1998--29 August 2001

Description: This report describes the major progress in understanding the physics of transition metals in silicon and their possible impact on the efficiency of solar cells that was achieved during the three-year span of this subcontract. We found that metal-silicide precipitates and dissolved 3d transition metals can be relatively easily gettered. Gettering and passivating treatments must take into account the individuality of each transition metal. Our studies demonstrated how significant is the difference between defect reactions of copper and iron. Copper does not significantly affect the minority-carrier diffusion length in p-type silicon, at least as long as its concentration is low, but readily precipitates in n-type silicon. Therefore, copper precipitates may form in the area of p-n junctions and cause shunts in solar cells. Fortunately, copper precipitates are present mostly in the chemical state of copper-silicide and can relatively easily be dissolved. In contrast, iron was found to form clusters of iron-oxides and iron-silicates in the wafers. These clusters are thermodynamically stable even in high temperatures and are extremely difficult to remove. The formation of iron-silicates was observed at temperatures over 900C.
Date: February 1, 2002
Creator: Weber, E. R.
Partner: UNT Libraries Government Documents Department

High-level core sample x-ray imaging at the Hanford Site

Description: Waste tank sampling of radioactive high-level waste is required for continued operations, waste characterization, and site safety. Hanford Site tank farms consist of 28 double-shell and 149 single-shell underground storage tanks. The single shell tanks are out-of-service an no longer receive liquid waste. Core samples of salt cake and sludge waste are remotely obtained using truck-mounted, core drill platforms. Samples are recovered from tanks through a 2.25 inch (in.) drill pipe in 26-in. steel tubes, 1.5 in. diameter. Drilling parameters vary with different waste types. Because sample recovery has been marginal an inadequate at times, a system was needed to provide drill truck operators with ``real-time feedback`` about the physical condition of the sample and the percent recovery, prior to making nuclear assay measurements and characterizations at the analytical laboratory. The Westinghouse Hanford Company conducted proof-of-principal radiographic testing to verify the feasibility of a proposed imaging system. Tests were conducted using an iridium 192 radiography source to determine the effects of high radiation on image quality. The tests concluded that samplers with a dose rate in excess of 5000 R/hr could be imaged with only a slight loss of image quality and samples less than 1000 R/hr have virtually no effect on image quality. The Mobile Core Sample X-Ray Examination System, a portable vendor-engineered assembly, has components uniquely configured to produce a real-time radiographic system suitable for safely examining radioactive tank core segments collected at the Hanford Site. The radiographic region of interest extends from the bottom (valve) of the sampler upward 19 to 20 in. The purpose of the Mobile Core Sample X-Ray Examination System is to examine the physical contents of core samples after removal from the tank and prior to placement in an onsite transfer cask.
Date: October 1, 1995
Creator: Weber, J. R. & Keve, J.K.
Partner: UNT Libraries Government Documents Department

Nondestructive Examination Equipment in the Hanford Site WRAP 1 and Retrieval Project

Description: The Waste Receiving and Processing Facility, Module 1 (WRAP-1) is currently under construction at the Hanford Nuclear Site in south-central Washington Stage. The facility is scheduled to begin operation in 1996. Its mission is to annually receive more than 6,800 55-gallon drums of both newly generated and retrieved contact-handled solid waste and prepare them for certification and disposal. WRAP 1, the Nondestructive Examination (NDE) System has two primary functions: To identify the presence or verify the absence of non-compliant materials in the un-manifested, retrieved drums, and to certify that all outgoing drums of TRU waste (newly generated and processed) are free of liquids and other non-compliant items. The Solid Waste Retrieval Facility, Phase 1 Project will unearth and recover the first 10,000 of 38,000 drums of suspect TRU waste buried between 1970 and 1985 for which no detailed contents manifests exist. Follow-on projects will recover the balance of the buried drums. To resolve safely issues about storing the newly unearthed drums, the containers and contents will be examined at the recovery site before the containers are placed in storage facilities.
Date: August 1, 1994
Creator: Keve, J. K. & Weber, J. R.
Partner: UNT Libraries Government Documents Department

Testing and evaluation of alternative process systems for immobilizing radioactive mixed particulate waste in cement

Description: Radioactive and Hazardous Mixed Wastes have accumulated at the Department of Energy (DOE) Hanford Site in south-central Washington State. Ongoing operations and planned facilities at Hanford will also contribute to this waste stream. To meet the Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions most of this waste will need to be treated to permit disposal. In general this treatment will need to include stabilization/solidification either as a sole method or as part of a treatment train. A planned DOE facility, the Waste Receiving and Processing (WRAP) Module 2A, is scoped to provide this required treatment for containerized contact-handled (CH), mixed low-level waste (MLLW) at Hanford. An engineering development program has been conducted by Westinghouse Hanford Company (WHC) to select the best system for utilizing a cement based process in WRAP Module 2A. Three mixing processes were developed for analysis and testing; in-drum mixing, continuous mixing, and batch mixing. Some full scale tests were conducted and 55 gallon drums of solidified product were produced. These drums were core sampled and examined to evaluate mixing effectiveness. Total solids loading and the order of addition of waste and binder constituents were also varied. The highest confidence approach to meet the WRAP Module 2A waste immobilization system needs appears to be the out-of-drum batch mixing concept. This system is believed to offer the most flexibility and efficiency, given the highly variable and troublesome waste streams feeding the facility.
Date: March 1, 1994
Creator: Weingardt, K. M. & Weber, J. R.
Partner: UNT Libraries Government Documents Department

Waste receiving and processing module 2A mixing tests status report

Description: The purpose of this report is to document the Phase II test conditions, observations, and results of this work. This report provides additional mixing performance test data and rheologic data that provide further indications that there are clear and distinct advantages in the preliminary choice of high-shear mixing alone, and high-shear dispersion in combination with, or followed by, a low-speed type mixer/stirrer for WRAP 2A facility design. Another objective was to determine if significant scale-up problems might exist in the various mix and mixer designs. In the later Phase 2 tests the test material quantities were significantly larger than in the Phase 1 tests.
Date: November 18, 1994
Creator: Weber, J. R. & Hull, K. J.
Partner: UNT Libraries Government Documents Department

Mobile X-ray imaging systems for the tank waste characterization project at the Hanford site

Description: Stored waste tank sampling of radioactive high-level nuclear waste is reilu ired for continued operations, waste characterization, and site safety. The Hanford site tank farms consist of 28 double- shell and 1.49 single-shell underground storage tanks. The ``full`` capacity of each of these tanks is approximately 1 million gallons. The waste stored in these tanks was generated as a result of defense materials production over the course of 4 decades. The single shell tanks are out-of-service and no longer receive liquid waste. Core samples of salt cake, liquid and sludge are remotely obtained using truck-mounted core drill platforms. Samples are recovered from the tanks through a 2.25-inch diameter drill pipe,, in segments contained in specially designed stainless steel samplers approximately 1.5-inch in outside diameter and 26-inches long. The sampled material in a given segment can include crystalline salt-cake, liquid, sludge and entrained gas. Drilling parameters will necessarily vary with different waste types, e.g., crystalline salt-cake versus sludge. At times, the core sample recovery has been marginal and inadequate for laboratory analysis needs. This necessitated a system to provide the drill-truck operators with ``real-time`` feedback about the physical condition of the sampled ``formation`` and the percent recovery, prior to receiving .,isual characterization information and nuclear assay measurements from the Hanford site 222-S Analytic!al laboratories, a process often requiring two week turn-around of data. This real- time information allows the drill-truck engineers to immediately vary the drilling parameters to maintain sample recovery.
Date: September 25, 1996
Creator: Weber, J.R.
Partner: UNT Libraries Government Documents Department

Copper in silicon: Quantitative analysis of internal and proximity gettering

Description: The behavior of copper in the presence of a proximity gettering mechanism and a standard internal gettering mechanism in silicon was studied. He implantation-induced cavities in the near surface region were used as a proximity gettering mechanism and oxygen precipitates in the bulk of the material provided internal gettering sites. Moderate levels of copper contamination were introduced by ion implantation such that the copper was not supersaturated during the anneals, thus providing realistic copper contamination/gettering conditions. Copper concentrations at cavities and internal gettering sites were quantitatively measured after the annealings. In this manner, the gettering effectiveness of cavities was measured when in direct competition with internal gettering sites. The cavities were found to be the dominant gettering mechanism with only a small amount of copper gettered at the internal gettering sites. These results reveal the benefits of a segregation-type gettering mechanism for typical contamination conditions.
Date: August 1, 1997
Creator: McHugo, S.A.; Flink, C. & Weber, E.R.
Partner: UNT Libraries Government Documents Department

Atomic scale interface structure of In{sub 0.2}Ga{sub 0.8}As/GaAs strained layers studied by cross-sectional scanning tunneling microscopy

Description: A molecular beam epitaxy-grown In{sub 0.2}Ga{sub 0.8}As/GaAs strained layer structure has been studied by scanning tunneling microscopy in cross-section on the (110) cleavage plane perpendicular to [001] the growth direction. Individual indium atoms were differentially imaged in the group III sublattice, allowing, a direct observation of the interface roughness due to the indium compositional fluctuation. In the In{sub 0.2}Ga{sub 0.8}As layers, Indium atoms are found in clusters preferentially along the growth direction with each cluster containing 2--3 indium atoms. Indium segregation induced asymmetrical interface broadening is studied on an atomic scale. The interface of In{sub 0.2}Ga{sub 0.8}As grown on GaAs is sharp within 2--4 atomic layers. The interface of GaAs grown on In{sub 0.2}Ga{sub 0.8}As is found to be broadened to about 5--10 atomic layers. The atomic scale fluctuation due to indium distribution is about 20 {angstrom} alone the interface in this case. The authors conclude that clustering and segregation are the main reason for the In{sub 0.2}Ga{sub 0.8}As/GaAs interface roughness.
Date: November 1, 1993
Creator: Zheng, J.F.; Weber, E.R. & Salmeron, M.B.
Partner: UNT Libraries Government Documents Department

Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders

Description: This primer is a tool to help prepare scientists for meetings with stakeholders. It was prepared for staff involved with the Natural and Accelerated Bioremediation Research (NABIR) program, sponsored by the U.S. Department of Energy. It discusses why some efforts in science communication may succeed while others fail, provides methods of approaching group interactions about science that may better orient expert participants, and summarizes experience drawn from observations of groups interacting about topics in bioremediation or the NABIR program. The primer also provides brief, useful models for interacting with either expert or non-expert groups. Finally, it identifies topical areas that may help scientists prepare for public meetings, based on the developers' ongoing research in science communication in public forums.
Date: September 27, 2000
Creator: Bilyard, G.R.; Word, C.J.; Weber, J.R. & Harding, A.K.
Partner: UNT Libraries Government Documents Department

Influence of the Richtmyer-Meshkov instability on the kinetic energy spectrum.

Description: The fluctuating kinetic energy spectrum in the region near the Richtmyer-Meshkov instability (RMI) is experimentally investigated using particle image velocimetry (PIV). The velocity field is measured at a high spatial resolution in the light gas to observe the effects of turbulence production and dissipation. It is found that the RMI acts as a source of turbulence production near the unstable interface, where energy is transferred from the scales of the perturbation to smaller scales until dissipation. The interface also has an effect on the kinetic energy spectrum farther away by means of the distorted reflected shock wave. The energy spectrum far from the interface initially has a higher energy content than that of similar experiments with a flat interface. These differences are quick to disappear as dissipation dominates the flow far from the interface.
Date: September 1, 2010
Creator: Weber, Christopher R. (University of Wisconsin-Madison, Madison, WI)
Partner: UNT Libraries Government Documents Department

Experimental investigation of the Richtmyer-Meshkov instability.

Description: The Richtmyer-Meshkov instability (RMI) is experimentally investigated using several different initial conditions and with a range of diagnostics. First, a broadband initial condition is created using a shear layer between helium+acetone and argon. The post-shocked turbulent mixing is investigated using planar laser induced fluorescence (PLIF). The signature of turbulent mixing is present in the appearance of an inertial range in the mole fraction energy spectrum and the isotropy of the late-time dissipation structures. The distribution of the mole fraction values does not appear to transition to a homogeneous mixture, and it is possible that this effect may be slow to develop for the RMI. Second, the influence of the RMI on the kinetic energy spectrum is investigated using particle image velocimetry (PIV). The influence of the perturbation is visible relatively far from the interface when compared to the energy spectrum of an initially flat interface. Closer to the perturbation, an increase in the energy spectrum with time is observed and is possibly due to a cascade of energy from the large length scales of the perturbation. Finally, the single mode perturbation growth rate is measured after reshock using a new high speed imaging technique. This technique produced highly time-resolved interface position measurements. Simultaneous measurements at the spike and bubble location are used to compute a perturbation growth rate history. The growth rates from several experiments are compared to a new reshock growth rate model.
Date: September 1, 2011
Creator: Weber, Christopher R. (University of Wisconsin-Madison, Madison, WI)
Partner: UNT Libraries Government Documents Department

Guidelines A Primer for Communicating Effectively with NABIR Stakeholders

Description: The purpose of this report is to help scientists communicate with stakeholders and the public (primarily nonscientists) about fundamental science research. The primary audience for this report is scientists involved in the Natural and Accelerated Bioremediation Research (NABIR) program of the U.S. Department of Energy. However, the information and insights in the report that are not program-specific should be helpful to scientists in other fundamental science research programs. The report first discusses why scientists should talk to stakeholders and the public, and the challenges associated with discussing the NABIR program. It is observed that communication initiatives can be characterized by three factors: relationships in the social environment, views of what constitutes communication, and accepted forms of communication practices and products. With a focus on informal science communication, recent efforts to gauge public understanding of science and the factors that affect public trust of science institutions are discussed. The social bases for scientist-nonscientist interactions are then examined, including possible sources of distrust and difficulties in transferring discussions of fundamental science from classrooms (where most of the public first learns about science) to public forums. Finally, the report contains specific suggestions for preparing, meeting, and following up on public interactions with stakeholders and the public, including themes common to public discussions of NABIR science and features of scientist-nonscientist interactions observed in interpersonal, small group, and large group interactions between NABIR scientists and stakeholders. A Quick Preparation Guide for Meeting NABIR Stakeholders is provided immediately following the Summary. It condenses some of the information and advice found in the text of the report.
Date: March 15, 2002
Creator: Weber, James R.; Word, Charlotte J. & Bilyard, Gordon R.
Partner: UNT Libraries Government Documents Department

Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders

Description: This version of the communication primer comprises two interlocking parts: Pat 1, a practical section, intended to prepare you for public interactions, and Part 2, a theoretical section that provides social and technical bases for the practices recommended in Part 1. The mutual support of practice and theory is very familiar in science and clearly requires a willingness to observe and revise our prior assumptions--in this document, we invoke both. We hope that is offering will represent a step both towards improving practice and maturing the theory of practical science communication.
Date: February 10, 2004
Creator: Weber, James R.; Schell, Charlotte J.; Marino, T & Bilyard, Gordon R.
Partner: UNT Libraries Government Documents Department

Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders

Description: This primer is a tool to help prepare scientists for meetings with stakeholders. It was prepared for staff involved with the Natural and Accelerated Bioremediation Research (NABIR) program, sponsored by the U.S. Department of Energy. It discusses why some efforts in science communication may succeed while others fail, provides methods of approaching group interactions about science that may better orient expert participants, and summarizes experience drawn from observations of groups interacting about topics in bioremediation or the NABIR program. The primer also provides brief, useful models for interacting with either expert or non-expert groups. Finally, it identifies topical areas that may help scientists prepare for public meetings, based on the developers' ongoing research in science communication in public forums.
Date: September 27, 2000
Creator: Bilyard, Gordon R.; Word, Charlotte J.; Weber, James R. & Harding, Anna K.
Partner: UNT Libraries Government Documents Department

Energies of x conduction band minima in disordered and ordered GaInP{sub 2} alloys

Description: A pressure-induced change from a direct bandgap to an indirect bandgap semiconductor has been observed in both partially ordered and disordered GaInP{sup 2}. By extrapolating back to ambient pressure the indirect {Gamma}-X band gap energy has been deduced. It was found that the {Gamma}-X conduction band separation remains almost constant between the ordered and disordered phases. A phenomenological model is proposed to explains this result.
Date: July 1, 1994
Creator: Uchida, K.; Yu, P. Y.; Weber, E. R. & Noto, N.
Partner: UNT Libraries Government Documents Department

Competition between gettering by implantation-induced cavities in silicon and internal gettering associated with SiO{sub 2} precipitation

Description: Dissolved or metallic impurities can degrade silicon integrated circuit (IC) device yields when present in the near surface, active device region. This is such a critical issue that the IC community has set specifications for the reduction of metallic impurities down to 2.5 {times} 10{sup 9} atoms/cm{sup 3}. The exceptionally high diffusivity and solubility of Cu and Fe in silicon and their presence in many processing tools makes these impurities of particular interest. Additionally, Cu is being considered as an interconnect material because of its low electrical resistivity which creates a high potential for contamination. Here, the gettering behavior of Cu and Fe was investigated in CZ silicon which contained both internal-gettering sites in the bulk due to SiO{sub 2} precipitation and a device-side layer of cavities formed by He implantation and annealing. The objective was to quantify the effectiveness of impurity gettering at cavities relative to the widely used internal-gettering process. Both rapid thermal anneals and furnace anneals were used during the gettering sequences to reveal transient effects as well as the final, thermodynamically-equilibrated condition. For temperatures of 700, 800 and 850 C, the cavity gettering was observed to predominate over internal gettering as indicated both by the number of gettered atoms in the cavities and the residual solution concentration in the device region. The results are interpreted in detail by numerically solving the diffusion equation with sink-related source terms based on earlier, fundamental studies of the underlying mechanisms of internal and cavity gettering.
Date: December 31, 1996
Creator: McHugo, S.A.; Weber, E.R.; Myers, S.M. & Petersen, G.A.
Partner: UNT Libraries Government Documents Department

Scanning tunneling microscopy of Si donors in GaAs

Description: Using scanning tunneling microscopy, we have identified and characterized Si donors (Si{sub Ga}) in GaAs located on the (110) surface and in subsurface layers. Si{sub Ga} on the surface shows localized features with characteristic structures in good agreement with a recent theoretical calculation. Si{sub Ga} in subsurface layers appears as delocalized protrusions superimposed on the background lattice, which are interpreted in terms of the modification of the tunneling due to the tip-induced band bending perturbed by the Si{sub Ga} Coulomb potential.
Date: July 1, 1993
Creator: Zheng, J.F.; Weber, E.R.; Liu, X.; Newman, N.; Ogletree, D.F. & Salmeron, M.B.
Partner: UNT Libraries Government Documents Department