Physical Sciences and Mathematics Commons^™

Nuclear Criticality, Shielding, And Thermal Analyses Of Separations Processes For The Transmutation Fuel Cycle, William Culbreth, Denis Beller

Separations Campaign (TRP)

The first step in any transmutation strategy is the separation of radionuclides in used nuclear fuel. The current separation strategy supporting the Advanced Fuel Cycle Initiative (AFCI) program is based on the use of a solvent extraction separation process to separate the actinides, fission products, and uranium from used commercial nuclear fuel, and on the use of pyrochemical separation technologies to process used transmuter fuels. To separate the fission products and transuranic elements from the uranium in used fuel, the national program is developing a new solvent extraction process, the Uranium Extraction Plus, or UREX+, process, based on the traditional …

Evaluation Of Fluorapatite As A Waste-Form Material, Dennis W. Lindle, Dale L. Perry

Separations Campaign (TRP)

Fluorapatite, fluorinated calcium phosphate, has been identified as a potential matrix for the entombment of the zirconium fluoride fission product waste stream from the proposed FLEX process. If the efficacy of fluorapatite based waste-storage can be demonstrated, then new and potentially more-efficient options for handling and separating high-level wastes, based on fluoride-salt extraction, will become feasible. This proposal is for renewal of the UNLV portion of a dual-path research project to develop a process to fabricate a synthetic fluorapatite waste form for the ZrF₄, FP waste stream, characterize the waste form, examine its performance under environmental conditions, and …

Evaluation Of Fluorapatite As A Waste-Form Material, Dennis W. Lindle, Dale L. Perry

Separations Campaign (TRP)

Argonne National Laboratory has proposed a new extraction procedure to handle TRISO-coated fuels, the Fluoride Extraction Process, or FLEX. The FLEX process is designed to separate the uranium in the fuel from the actinides and most fission products by taking advantage of the unique properties of uranium hexafluoride (UF₆). In the FLEX process, the used TRISO fuel is reacted with zirconium fluoride salt, forming UF₆ and the fluoride salts of the actinides and fission products. At process temperatures, the UF6 volatizes into a gas, and is released from the molten salt mixture. This leaves behind the actinides …

Perspectives On Economic Analyses For High Level Waste Disposal, Helen R. Neill, Robert H. Neill

Public Policy and Leadership Faculty Publications

There are both internal and external pressures on the U.S. Department of Energy (DOE) to reduce costs of disposal and still maintain radiation protection to both present and future generations. The question arises whether both of these goals are attainable.

Design And Evaluation Of Processes For Fuel Fabrication, Georg F. Mauer

Fuels Campaign (TRP)

The goal of this research project is to provide technical support to process designers working on the development of the fuel cycles for transmutation applications. Detailed process models are developed to better define the impact of fuel choice on the transmuter fuel cycle, including relative process losses, waste generation, and plant capital cost. These process models provide insight regarding required plant size and number of plants needed to mesh with the fuel recycling line. They also determine requirements for automation.

Manufacturing models for large-scale production in a hot cell environment are also developed. Combined, these two models allow the assessment …

Design And Evaluation Of Processes For Transmuter Fuel Fabrication, Georg F. Mauer

Fuels Campaign (TRP)

• Project Objective: examine autonomous robotic fuel fabrication processes with regard to hot cell and equipment design, operations, and costs.

• Fabrication processes for different fuel types differ in terms of equipment types, throughput, and cost.

• Design options are restricted by the requirement to employ only radiation-hardened machinery and components

• Benefit to Department of Energy: decision support for the selection of the most suitable manufacturing process.

Evaluation Of Sampling Strategies On Load Estimation For Illinois River At Highway 59, T. S. Soerens, M. A. Nelson

Technical Reports

This study investigated the precision and accuracy of the two load calculation techniques. The study compared total phosphorus loads calculated by integration of Arkansas Water Resources Center (AWRC) intensive sampling data to loads calculated by a regression technique (rating curve) using fewer data. The 1998 AWRC dataset from the Illinois River at Arkansas Highway 59 was sub-sampled in a manner to simulate fixed period monitoring schemes supplemented with storm sampling. The ESTIMATOR software program was used to calculate loads. These loads were compared to the integrated load. The error of the integrated load when the variation in concentration between samples …

Relative Invertebrate Availability In Nebraska's Conservation Reserve Management Access Program, Ronald J. Leathers

Electronic Theses and Dissertations

The Conservation Reserve Management Access Program (CRP-MAP) is a joint effort of the Nebraska Game and Parks Commission and Pheasants Forever of Nebraska that seeks to address brood habitat needs of pheasants (Phasianus colchicus) and other grassland birds by light disking and interseeding legumes into portions of aging CRP fields. The program has two specific goals - increasing the total invertebrate availability as a food source for pheasant chicks and increasing the structural complexity of vegetation. This study compares invertebrate biomass and structural complexity of vegetation in treated (disked and interseeded with legumes) and idle portions of CRP-MAP fields to …

A Contrast-Based Neural Control System For Ant Navigation, Joanna R. Wares, Predrag-Peter Ilich, Daniel P. Dougherty

Department of Math & Statistics Faculty Publications

A mathematical model for a neural control system of ant locomotion was developed. Contrast-based detectors using excitation and inhibition were tuned to specific contrast orientations. A control system using multiple orientation contrast detectors was then developed and optimized for a model ant, which could move via a biased random walk. The system allowed sufficient control to guide the ant through various mazes.

Brane Factories, Eun-Joo Ahn, Marco Cavaglia, Angela V. Olinto

Physics Faculty Research & Creative Works

We propose that higher-dimensional extended objects (p-branes) are created by super-Planckian scattering processes in theories with TeV scale gravity. As an example, we compute the cross section for p-brane creation in a (n + 4)-dimensional spacetime with asymmetric compactification. We find that the cross section for the formation of a brane which is wounded on a compact submanifold of size of the fundamental gravitational scale is larger than the cross section for the creation of a spherically symmetric black hole. Therefore, we predict that branes are more likely to be created than black holes in super-Planckian …

Winter Ecology Of Kokanee: Implications For Salmon Management, G. B. Steinhart, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

We sampled various limnological parameters and measured growth and diet of age-0 kokanee Oncorhynchus nerka (lacustrine sockeye salmon) during two winters in a high-mountain lake of the Sawtooth Valley, Idaho. Although winter has been recognized as an important period for many warmwater fishes and for stream-dwelling salmonids, winter limitations have only recently been studied for coolwater and coldwater species. Ice and snow cover in winter limited light penetration. As a result, chlorophyll-a and zooplankton density were lower in ice-covered periods than during ice-free periods. The weight of stomach contents was often below a maintenance ration, yet the incidence of empty …

A Performance Analysis Of Distributed Algorithms In Javaspaces, Corba Services And Web Services, Suresh Sunku

UNF Graduate Theses and Dissertations

Implementation of distributed parallel algorithms on networked computers has always been very difficult until the introduction of service-oriented architectures (SOA) like JavaSpaces service, CORBA services and Web Services. Algorithms of the type Master/Worker pattern are implemented with relative ease using the SOAs. This project analyzes the performance of such algorithms on three contemporary SOAs namely JavaSpaces service, CORBA services and Web Services. These architectures make the implementations of distributed algorithms reasonably fault tolerant and highly and dynamically scalable. Also, the systems built on these architectures are generally loosely coupled and operate asynchronously.

In this project we measure and analyze the …

Charge Storage, Conductivity And Charge Profiles Of Insulators As Related To Spacecraft Charging, John R. Dennison, A. R. Frederickson, Prasanna Swaminathan

All Physics Faculty Publications

Dissipation of charges built up near the surface of insulators due to space environment interaction is central to understanding spacecraft charging. Conductivity of insulating materials is key to determine how accumulated charge will distribute across the spacecraft and how rapidly charge imbalance will dissipate. To understand these processes requires knowledge of how charge is deposited within the insulator, the mechanisms for charge trapping and charge transport within the insulator, and how the profile of trapped charge affects the transport and emission of charges from insulators. One must consider generation of mobile electrons and holes, their trapping, thermal detrapping, mobility and …

The Helically Reduced Wave Equation As A Symmetric Positive System, Charles G. Torre

All Physics Faculty Publications

Motivated by the partial differential equations of mixed type that arise in the reduction of the Einstein equations by a helical Killing vector field, we consider a boundary value problem for the helically-reduced wave equation with an arbitrary source in 2+1 dimensional Minkowski spacetime. The reduced equation is a second-order partial differential equation which is elliptic inside a disk and hyperbolic outside the disk. We show that the reduced equation can be cast into symmetric-positive form. Using results from the theory of symmetric-positive differential equations, we show that this form of the helically-reduced wave equation admits unique, strong solutions for …

Secondary Electron Production And Transport Mechanisms By Measurement Of Angle-Energyresolved Cross Sections Of Secondary And Backscattered Electrons, Jason Kite, John R. Dennison

All Physics Faculty Publications

The angle dependence of emitted electron spectra from a polycrystalline Au surface has been measured at several incident electron beam energies. The range of incident energies (~100 eV to 2500 eV) extends from below the first crossover energy, through Emax, to above the second crossover energy. The traditional distinction between secondary electrons (50 eV) is found to be inconsistent with our energy- and angle-resolved measurements. We suggest a more “natural” delineation occurs at the local minima of the emission spectra; this feature is studied as a function of incident energy and emission angle. This work is also supported by the …

Lisa, Binary Stars, And The Mass Of The Graviton, Curt Cutler, William A. Hiscock, Shane L. Larson

All Physics Faculty Publications

We extend and improve earlier estimates of the ability of the proposed LISA (Laser Interferometer Space Antenna) gravitational wave detector to place upper bounds on the graviton mass m_g by comparing the arrival times of gravitational and electromagnetic signals from binary star systems. We show that the best possible limit on m_g obtainable this way is ∼50 times better than the current limit set by solar system measurements. Among currently known, well-understood binaries, 4U1820-30 is the best for this purpose; LISA observations of 4U1820-30 should yield a limit ≈3-4 times better than the present solar system bound. AM …

Water Management: Partnerships For Future Directions (Research And Testing Education Support Outreach), Mac Mckee

Reports

The UWRL is uniquely positioned to form collaborations with USU departments, other academic institutions and water centers, government, and private sector organizations involved in addressing water issues. The strong and consistent support of the State of Utah illustrates the importance of water and the creation of knowledge to manage water in Utah and the surrounding western states. The scope of projects ranges from multimillion dollar partnerships related to soil and groundwater remediation with national impacts, to small scale projects related to outreach to a specific city or county public sector audience. The UWRL mission, the strategy used to accomplish the …

Electron Emission Properties Of Insulator Materials Pertinent To The International Space Station, C. D. Thomson, V. V. Zavyalov, John R. Dennison, Jodie Corbridge

All Physics Faculty Publications

We present the results of our measurements of the electron emission properties of selected insulating and conducting materials used on the International Space Station (ISS). Utah State University (USU) has performed measurements of the electron-, ion-, and photon-induced electron emission properties of conductors for a few years, and has recently extended our capabilities to measure electron yields of insulators, allowing us to significantly expand current spacecraft material charging databases. These ISS materials data are used here to illustrate our various insulator measurement techniques that include: i) Studies of electron-induced secondary and backscattered electron yield curves using pulsed, low current electron …

Measurement Of Conductivity And Charge Storage In Insulators Related To Spacecraftcharging, A. R. Fredrickson, John R. Dennison

All Physics Faculty Publications

Novel methods have been developed to measure conductivity and charge storage in thin film insulating spacecraft materials subjected to space radiations. For a variety of such samples, conductivity values differ by up to 104 from values based on ASTM standards. Conductivity and charge storage properties are found to be functions of prior radiation history. A highly-charged insulator emits electrons for hours (Malter Effect) after the irradiation beam is turned off. Visible light can be used to induce emission from previously charged samples with shallow traps.

Lisa Data Analysis: Doppler Demodulation, Neil J. Cornish, Shane L. Larson

All Physics Faculty Publications

The orbital motion of the Laser Interferometer Space Antenna (LISA) produces amplitude, phaseand frequency modulation of a gravitational wave signal. The modulations have the effect of spreading a monochromatic gravitational wave signal across a range of frequencies. The modulations encode useful information about the source location and orientation, but they also have the deleteriousaffect of spreading a signal across a wide bandwidth, thereby reducing the strength of the signalrelative to the instrument noise. We describe a simple method for removing the dominant, Doppler,component of the signal modulation. The demodulation reassembles the power from a monochromatic source into a narrow spike, …

Lisa Data Analysis: Source Identification And Subtraction, Neil J. Cornish, Shane L. Larson

All Physics Faculty Publications

The Laser Interferometer Space Antenna will operate as an AM-FM receiver for gravitational waves. For binary systems, the source location, orientation and orbital phase are encoded in the amplitude and frequency modulation. The same modulations spread a monochromatic signal over a range of frequencies, making it difficult to identify individual sources. We present a method for detecting and subtracting individual binary signals from a data stream with many overlapping signals.

Comparison Of Classical And Charge Storage Methods For Determining Conductivity Of Thin Film Insulators, Prasanna Swaminathan, A. R. Frederickson, John R. Dennison, Alec Sim, J. Brunson, Eric Crapo

All Physics Faculty Publications

Conductivity of insulating materials is a key parameter to determine how accumulated charge will distribute across the spacecraft and how rapidly charge imbalance will dissipate. Classical ASTM and IEC methods to measure thin film insulator conductivity apply a constant voltage to two electrodes around the sample and measure the resulting current for tens of minutes. However, conductivity is more appropriately measured for spacecraft charging applications as the "decay" of charge deposited on the surface of an insulator. Charge decay methods expose one side of the insulator in vacuum to sequences of charged particles, light, and plasma, with a metal electrode …

Instrumentation For Studies Of Electron Emission And Charging From Insulators, C. D. Thomson, V. V. Zavyalov, John R. Dennison

All Physics Faculty Publications

Making measurements of electron emission properties of insulators is difficult since insulators can charge either negatively or positively under charge particle bombardment. In addition, high incident energies or high fluences can result in modification of a material’s conductivity, bulk and surface charge profile, structural makeup through bond breaking and defect creation, and emission properties. We discuss here some of the charging difficulties associated with making insulator-yield measurements and review the methods used in previous studies of electron emission from insulators. We present work undertaken by our group to make consistent and accurate measurements of the electron/ion yield properties for numerous …

Hydrologic Properties And Structure Of The Mozumi Fault, Central Japan, Craig B. Forster, James P. Evans, Hidemi Tanaka, Ronald Jeffreys, Tsuyoshi Nohara

Geosciences Faculty Publications

Analyses of rocks from the Active Fault Survey Tunnel (AFST) provides insight into the structure and hydrogeology of the northeast-trending Mozumi-Sukenobu fault, an active strike-slip fault with 125 to 500 m of right-lateral slip in central Japan. Interlayered regions of sub-vertical permeability zones formed by cataclasis and slip on clay-rich foliated zones. Core samples range from 10⁻¹⁹ m² to almost 10⁻¹³ m². CFC analyses of waters from the fault zone show that water entering the tunnel is 27–36 years old, yielding a bulk fault permeability of 10⁻¹⁴ to 10⁻¹⁵ m². The …

Comparison Between Hydrogen And Dihydrogen Bonds Among H3bnh3, H2bnh2, And Nh3, T. Kar, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Several possible binary complexes among ammonia-borane, aminoborane, and ammonia, via hydrogen and/or dihydrogen bonds, have been investigated to understand the effect of different hybridization. Møller–Plesset second-order perturbation theory with aug-cc-pVDZ basis set was used. The interaction energy is corrected for basis set superposition error, and the Morokuma–Kitaura method was employed to decompose the total interaction energy. Like H₃BNH₃, the sp² hybridized H₂BNH₂ also participates in H- and dihydrogen bond formation. However, such bonds are weaker than their sp³ analogs. The contractions of BN bonds are associated with blueshift in …

A Phase I And Pharmacologic Study Of Weekly Gemcitabine In Combination With Infusional 5-Fluorodeoxyuridine And Oral Calcium Leucovorin, Jean L. Grem, Mary G. Quinn, Bruce Keith, Brian P. Monahan, J. Michael Hamilton, Yan Xu, Nancy Harold, Dat Nguyen, Chris H. Takimoto, Anthony Rowedder, Janet Pang, Geraldine Morrison, Alice Chen

Chemistry Faculty Publications

Purpose: Since preclinical studies have shown more than additive cytotoxicity and DNA damage with the combination of gemcitabine and 5-fluoro-2′-deoxyuridine (FUDR), we studied this combination in a phase I trial. Methods: Gemcitabine alone was given in cycle 1 as a 24-h, 2-h or 1-h i.v. infusion weekly for 3 of 4 weeks; if tolerated, a 24-h i.v. infusion of FUDR was added with oral leucovorin. The cycle was aborted for grade 3 thrombocytopenia, grade 4 neutropenia, and grade 2 or worse nonhematologic toxicity. Results: During cycle 1, six of eight patients who received 150 or 100 mg/m2 over 24 h …

Estimation Of Hydraulic Conductivity From Borehole Flowmeter Tests Considering Head Losses, Vitaly A. Zlotnik, Brian R. Zurbuchen

Department of Earth and Atmospheric Sciences: Faculty Publications

Recent numerical studies have demonstrated that the conventional interpretation of the borehole flowmeter test (BFT) may lead to considerable errors in estimates of the horizontal hydraulic conductivity (K_r) due to neglect of head loss across the electromagnetic borehole flowmeter (EBF). Even in uniform aquifers, the conventional interpretation underestimates K_r at the base and overestimates K_r at the top of the aquifer. In this paper, we derive exact analytical solutions for hydraulic head and streamlines induced by the BFT in a confined homogeneous aquifer. The solutions explicitly consider head loss across the EBF. The derived analytical solutions …

Coastal Resources Management Training Needs Assessment: Strategies And Opportunities, Kevin O'Brien, Claudette Robey, Wendy A. Kellogg, Michael J. Tevesz

All Maxine Goodman Levin School of Urban Affairs Publications

The Old Woman Creek National Estuarine Research Reserve (OWC), Ohio Department of Natural Resources-Coastal Management Program (ODNRCMP), and Ohio Sea Grant College Program engaged the Great Lakes Environmental Finance Center (GLEFC) to aid them in developing a coastal resources management training initiative for Ohio coastal decision-makers. Coastal decision-maker professionals are expected to formulate effective strategies and apply interdisciplinary approaches to solving problems and policy issues that affect the environments of coastal regions. There are a number of professionals in a variety of occupations who make decisions regarding coastal and environmental policy issues. These individuals include those within the coastal resources …

Census 2000 Demographic Profile Report Of The Older Adult Population In Cuyahoga, Lake, Geauga, Lorain And Medina Counties, Mark Salling, Sharon Bliss, Mcnamara, Brian

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.

Needs Assessment: A Report On Seven Focus Groups In Ohio: Report Summary, Kevin O'Brien, Daniel Baracskay, Wendy A. Kellogg, Michael Mcgoun, Claudette Robey, Michael J. Tevesz, Kirstin S. Toth

All Maxine Goodman Levin School of Urban Affairs Publications

Coastal decision-makers and training providers in the Ohio Lake Erie basin participated in seven focus groups to generate information on coastal resources knowledge and training needs. Six of the focus groups were comprised of a cross-section of professionals who make decisions affecting watershed areas or Lake Erie coastal areas (non-providers); the seventh was comprised of training providers (providers). Discussions centered on two main areas: core knowledge needs and training needs.