Physical Sciences and Mathematics Commons^™

Discrete-To-Continuum Simulation Approach To Polymer Chain Systems: Subdiffusion, Segregation, And Chain Folding, Grace M. Foo, Ras B. Pandey

Faculty Publications

A discrete-to-continuum approach is introduced to study the static and dynamic properties of polymer chain systems with a bead-spring chain model in two dimensions. A finitely extensible nonlinear elastic potential is used for the bond between the consecutive beads with the Lennard-Jones (LJ) potential with smaller (R_c=2^1/6σ=0.95) and larger (R_c=2.5σ=2.1) values of the upper cutoff for the nonbonding interaction among the neighboring beads. We find that chains segregate at temperature T =1.0 with R_c=2.1 and remain desegregated with R_c=0.95. At low temperature (T=0.2), chains become folded, …

Mössbauer-Effect And X-Ray-Absorption Spectral Study Of Sonochemically Prepared Amorphous Iron, Gary J. Long, Dimitri Hautot, Quentin A. Pankhurst, Denis Vandormael, Fernande Grandjean, Jean Pierre Gaspard, Valérie Briois, Taeghwan Hyeon, Kenneth S. Suslick

Chemistry Faculty Research & Creative Works

The Mössbauer spectra of amorphous iron, prepared by using sonochemical methods, exhibit a broad magnetic hyperfine sextet at both 78 and 295 K. The spectra do not change with time if the amorphous iron is not exposed to oxygen or moisture. An analysis of the spectra with the method of Lines and Eibschütz yields average magnetic hyperfine fields of 29.1 and 25.9 T at 78 and 295 K, respectively. The corresponding moments of 1.9_B and 1.7_B agree well with values obtained from earlier magnetization studies and, further, provide strong experimental support for earlier calculations of the magnetic moments …

Thermoconvective Instability Of Paramagnetic Fluids In A Nonuniform Magnetic Field, J. Huang, D. D. Gray, Boyd F. Edwards

All Physics Faculty Publications

The effect of a static, nonuniform magnetic field on a laterally unbounded nonconducting paramagnetic fluid layer heated from below or above is studied using a linear stability analysis of the Navier-Stokes equations supplemented by Maxwell’s equations and the appropriate magnetic body force. Buoyancy-driven convection can be controlled by subjecting the layer to a nonuniform magnetic field. Theoretical predictions agree with experimental observations.

Satellite Studies Of Mid- And Low-Latitude Ionospheric Disturbancezonal Plasma Drifts, L. Scherliess, Bela G. Fejer

Bela G. Fejer

We use low- and mid-latitude zonal ion drift observations from the DE-2 satellite and auroral electrojet indices to study the temporal and latitudinal variations of F-region perturbation drifts during magnetically disturbed conditions. These perturbation drifts are driven by magnetospheric and ionospheric disturbance dynamo electric fields with time constants from less than one to several hours. We determine, initially, the drift patterns due to the prompt penetration of magnetospheric electric fields and of longer lasting disturbances. In this study, we concentrate on the properties of the longer lasting perturbations which occur with latitude-dependent time delays after enhancements in the high-latitude ionospheric …

Determination Of Intracellular Glutathione Concentration Using Monobromobimane, Ryan R. Owens

Undergraduate Honors Capstone Projects

Asbestos is a general term for a group of fibrous silicates. Diseases such as asbestosis, bronchogenic carcinoma, and mesothelioma have been linked to asbestos exposure (1,2). The 1 two classes of asbestos, serpentine and amphibole, are distinguished by differences in structure and chemical composition (3). The amphibole crocidolite contains 27% iron while the serpentine chrysotile contains only 2-3% iron. The higher iron content of crocidolite is proposed to be a contributing factor for a much higher incidence of cancer with crocidolite exposure compared with chrysotile exposure ( 4). Iron mobilized intracellularly from asbestos fibers may participate in the formation of …

A Preliminary Analysis Of The Fluid History Of A Normal Fault In The Keno Pit, Alligator Ridge Mining District, White Pine County, Nevada, John G. Solum

Undergraduate Honors Capstone Projects

The flow of oil along faults is only poorly understood. In many cases a fault is the only means of transportation for the oil from its area of deposition to its current location. This assumption is reasonable due to chemical fingerprinting of oil. In some cases the oil in a reservoir and the oil in a fault zone have been analyzed chemically and found to be the same. The problem is this; early in a fault's history it produces a thin layer of fine-grained material between its fault surfaces. This condition is not conductive to fluid flow. Therefore another mechanism …

On The Model Selection In A Frailty Setting, Jill F. Lundell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When analyzing data in a survival setting, whether of people or objects, one of the assumptions made is that the population is homogeneous. This is not true in reality and certain adjustments can be made in the model to account for heterogeneity. Frailty is one method of dealing with some of this heterogeneity. It is not possible to measure frailty directly and hence it can be very difficult to determine which frailty model is appropriate for the data in interest. This thesis investigates three model selection methods in their effectiveness at determining which frailty distribution best describes a given set …

Perceived Fairness And Effectiveness Of Rangeland Collaborative Processes, Kimberly J. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Involvement in collaborative partnerships in natural resource management has become a popular method for natural resource management agencies to collect public input, cope with conflicts, and develop ecosystem management plans. This thesis evaluates various collaborative processes, emphasizing multiple-owner partnerships. Qualitative interviews of 46 landowners in Utah were conducted to reveal concerns and suggestions regarding multiple-owner landscape-level collaborative partnerships. Landowners were concerned about private property rights infringement and losing control of their private land. Landowners were primarily concerned about the fairness and effectiveness of any partnership in which they were involved.

However, they were willing to consider participating if certain procedural …

Quaternary Amino Acid Geochronology Of The Lahontan Basin, Nevada, And The Chewaucan Basin, Oregon, Jeffrey Bigelow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Amino acid geochronology based on fossil molluscs provides a useful approach to determining the Quaternary history of Great Basin lakes. The Lahontan basin, Nevada, and the Chewaucan basin, Oregon, in the northwest corner of the Great Basin, both contained lakes during the Quaternary. The aim of this study is to improve the Quaternary geochronology in these two basins by measuring time-dependent changes in amino acids preserved in fossil molluscan shells. The abundance of D-alloisoleucine relative to Lisoleucine (All) characterizes the extent of racemization, which increases with age and Ul forms the basis of relative and correlated ages. An age-calibration curve …

All-Sky Measurements Of The Mesospheric "Frontal Events" From Bear Lake Observatory, Utah, Seon-Hee Seo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies of internal gravity waves in the earth's upper atmosphere are of considerable interest. These waves play a very important role in the dynamics of the mesosphere and lower thermosphere (ML T) region where they can transfer large amounts of energy and momentum from the lower atmosphere via wave saturation and dissipation. In particular, small-scale short-period ( < 1 hour) waves of the type regularly recorded by all-sky nightglow imagers operated by Utah State University (USU) are known to be very important contributors. In this thesis attention is focused on a subset of small-scale wave phenomena recently discovered using such image data, the so called "frontal events." Frontal events have distinguishable characteristics from usual short-period ( < 1 hour) gravity waves. The principal characteristics are a well defined leading "front, " which exhibits a sharp change in intensity followed by a coherent wave trail (often extending from horizon to horizon) and relatively high phase speeds ( > 50ms^-1) Another unusual characteristic of "frontal events" is an apparent reversal in contrast of the wave structures as imaged in the hydroxyl (OH) emission (peak altitude - 87 km) when compared with the oxygen (OJ) "green line" (557.7 nm) emission (peak …

The Role Of An Invasive Exotic Plant On The Structure Of Aquatic Invertebrate Assemblages: Tamarix In The Southwest United States, Bert Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past 100 years, riparian vegetation communities throughout the Southwest United States have been extensively invaded by Tamarix spp. (saltcedar). Saltcedar derives its common name from its physiological adaptation to excrete salts. The production of Tamarix detritus with associated secondary chemicals may affect the quality of aquatic invertebrate food and habitat resources. An alteration in food and habitat quality may affect the composition and structure of aquatic invertebrate assemblages.

A series of experiments was conducted contrasting aquatic invertebrate assemblage densities, colonization rates, and growth rates associated with Tamarix versus native vegetation, Populus fremontii (cottonwood) and Salix exigua (willow), to …

Center For Sustainable Agricultural Systems Newsletter, May/June 1998

Center for Sustainable Agricultural Systems: Newsletters (1993-2000)

Contents:

A Snapshot of CSAS Activity in Research, Education and Training

Vollmar to Be Interim CSAS Director

Highlights of Upcoming New Book: Under the Blade (Part 1)

CSAS Publishes Two More "Green Volumes"

USDA to Change Proposed Organic Standards

$31 Million Awarded in Fund for Rural America Grants

Sustainable Ag Seminar Series to Focus on Alternative Farming Systems and Foodsheds

Call for 1999 NCR SARE Preproposals

Newsletter Mailing List Clarification

Design And Implementation Of Triveni: A Process-Algebraic Api For Threads + Events, Christopher P. Colby, Lalita Jategaonkar Jagaeesan, Radhakrishnan Jagadeesan, Konstantin Laufer, Carlos Puchol

Computer Science: Faculty Publications and Other Works

We describe Triveni, a framework and API for integrating threads and events. The design of Triveni is based on an algebra, including preemption combinators, of processes. Triveni is compatible with existing threads standards, such as Pthreads and Java threads, and with the event models structured on the Observer pattern. We describe the software architecture and algorithms underlying a concrete implementation of Triveni in Java. This environment includes specification based testing of safety properties. The results described in the paper have been used to integrate process-algebraic methods into (concurrent) object orientated programming.

A Comparison Of Deterministic And Stochastic Population Models, Clarissa Smith

Masters Theses & Specialist Projects

In this thesis, the author considers the exponential and the predator-prey population models. A comparison of the deterministic and stochastic versions of each is made. The author shows that on average a stochastic model is precisely its corresponding deterministic model. The first model considered is the exponential model. A solution is provided for both the deterministic and the stochastic versions. A predator-prey model is also analyzed. A solution of the stochastic predator-prey model is shown to be intractable. Analysis of this model is performed through numerical simulation.

Invariant Representations Of Finite Rotation Matrices And Some Applications, N. L. Manakov, A. V. Meremianin, Anthony F. Starace

Anthony F. Starace Publications

Standard representations of finite rotation matrices (FRM) are defined by expressions that are wedded to two particular coordinate frames such as, e.g., are involved in the definition of Euler angles. We present here representations for the FRM in invariant tensor forms comprised of vectors defined in a space-fixed coordinate frame K. Three explicit expressions for a FRM are presented: First, in terms of tensor products of the spherical or Cartesian basis vectors of frame K, second in a differential form containing the tensor products of gradient operators, and, third, as the superposition of so-called “minimal” bipolar harmonics depending …

Characterization Of Dielectric Properties Of Earth Materials At Low Frequencies, Tarrah Dawn Henrie

Undergraduate Honors Capstone Projects

Sharma and de Lima (1992) have proposed a model based on Fixman's theoretical development of charged macromolecules in external fields (1980). There are three types of charges considered: the fixed surface charges that are covalently bonded, the layer of bound counterions, and the diffuse layer (Fixman, 1980, Lyklema, 1983 ). Figure (1) shows these different layers. Other common theories, such as Schurr's only consider the bound counterions and the diffuse layer. Schurr assumes that the diffuse layer ions can exchange with the electrolyte. A consequence of this assumption is the lack of polarization of the diffuse layer. This leads to …

Establishment Of A Nighthawk Migration Monitoring Program, Jeri Paige Guilliams

Theses & Honors Papers

The Nighthawk Migration Monitoring Program was initiated in 1997 to study the Common Nighthawk, Chordeiles minor. Modeled after the Hawk Migration Association of North America's hawkwatching methodology, the program enlisted volunteers to record time of day for peak flight, time of season for peak flight, weather conditions affecting migration, and other data. Volunteers were enlisted by establishment of a web­ page and e-mail address, preparation and circulation of a brochure, and through mail.

Individual chapters of the Virginia Society of Ornithology and others expressing interest were sent a letter, brochure, a Nighthawk Count Report Form, and an instruction sheet for …

Structure Of 5-Nitro-2-Tosylaminobenzaldehyde Di(Morpholin-4-Yl)Aminal Complex With Carbon Tetrachloride, V. N. Khrustalev, Sergey V. Lindeman, L. Yu Ukhin, G. I. Orlova, T. N. Gribanova, O. V. Shishkin

Chemistry Faculty Research and Publications

The 5-nitro-2-tosylaminobenzaldehyde di(morpholin-4-yl)aminal forms a stable complex with carbon tetrachloride in the crystal phase. X-ray structural study of this complex indicates an essentially shortened intermolecular contact of 2.89 Å between the oxygen atom of the nitro group and one of the chlorine atom of the CCI₄ molecule. Quantum-chemical calculations by semiempirical AMI method showed that the formation of such complex did not cause considerable decrease of system energy or change of charge distribution in molecules. It was supposed that this associate has van der Waals character.

Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heterogeneous spatial and temporal distributions of soil resources important to plant growth have been documented in the sagebrush steppe ecosystem. There can exist as much variability in soil resources within the root zone of individual plants as exists across an entire field. The objective of this dissertation research was to evaluate how plants respond to, utilize and influence the spatial heterogeneity of soil resources. The three specific sets of questions addressed are outlined in the three main chapters of this dissertation.

My first study addressed how the number and concentration of phosphorus (P) patches in the root zone of an …

Statistical Characterization Of Fluvial-Deltaic Reservoirs With Archetypes, Laura L. Watkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Optimizing the extraction of oil and other hydrocarbon products from existing sites is important. One source of hydrocarbon products is reservoirs found within sedimentary rock formations. Understanding fluid behavior within such formations can be quite useful in optimizing oil production. Fluid behavior within sedimentary formations is influenced by the bedform structure and permeabilities within the formation. Thus, we are concerned with developing a physically and statistically valid method of characterizing sedimentary rock formations. The use of archetypal analysis to generate synthetic bedforms, as well as the use of Kriging to assign permeabilities within a bedform, was explored. With these tools, …

Late Pleistocene Glacial Chronology Of The Western Ahklun Mountains, Southwestern Alaska, Jason P. Briner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

New glacial mapping and 35 cosmogenic ³⁶Cl surface exposure ages, the first ever reported from Alaska, constrain the extent and timing of late Pleistocene glacial fluctuations in the western Ahklun Mountains, southwestern Alaska. Morphometric and soil relative-age data characterize two main drift units deposited during the Arolik Lake and Klak Creek glaciations, named herein. During the Arolik Lake glaciation (early Wisconsin), outlet glaciers emanated from an ice cap over the central portion of the Ahklun Mountains and deposited moraines at or beyond the modern coast. These moraines have slope angles averaging about 11° and crests averaging about 35 m …

Three-Dimensional Structure Of Small Strike-Slip Fault Zones In Granitic Rock: Implications For Fault-Growth Models, Kim R. Robeson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three small strike-slip fault zones exposed in granitic rock in the central Sierra Nevada, California, provide field-based data to construct three-dimensional representations of each fault zone in order to compare with the geometries predicted by existing fault-growth models. All three fault zones are nearly vertical, strike -N60°E, and have left-lateral slip. The fault zones range from 60 to 140 m in length and 1 to 12 m wide. Each fault zone consists primarily of parallel to subparallel fracture and fault traces 2 to 56 m long and is separated 25 cm to 7 m by intact rock. One fault zone …

Small Strike-Slip Faults In Granitic Rock: Implications For Three-Dimensional Models, Siang Joo Lim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The geometry and mineralization features of small left-lateral strike-slip faults and associated fractures in Lake Edison Granodiorite of the central Sierra Nevada, California, were examined in order to model the three-dimensional structure of strike-slip faults. These faults, which are reactivated joints, were also examined to determine fault sizes, starting joint size, and evidence for fluid flow.

The associated secondary fractures are usually found in the dilational quadrants of fault-tip regions. The longest fault-segment trace is 32.14 m; the longest joint trace is 22 m. The joint population length (l) is represented by a power-law distribution (l^{-n …}

Measuring The Applicability Of The Seville Strategy To The Mammoth Cave Area Biosphere Reserve, Debra Kreitzer

Masters Theses & Specialist Projects

The dominant paradigms of the past decade involve the preservation of biodiversity through the use of landscape corridors and buffer zones, as well as the integration of economic growth through sustainable use. The International Biosphere Reserve (IBR) program, as defined in the Seville Strategy, encourages locations already involved in conservation to continue to protect biodiversity and foster harmonious relationships between humans and their environment through sustainable development. An excellent example of an IBR is the Mammoth Cave Area Biosphere Reserve (MCABR) in south-central Kentucky. In order to measure the significance of the implementation of the Seville Strategy in the MCABR, …

Radio Pulse Properties Of The Millisecond Pulsar Psr J0437-4715. I. Observations At 20 Centimeters, F. A. Jenet, S. B. Anderson, V. M. Kaspi, T. A. Prince, S. C. Unwin

Physics and Astronomy Faculty Publications and Presentations

We present a total of 48 minutes of observations of the nearby, bright millisecond pulsar PSR J0437-4715 taken at the Parkes Observatory in Australia. The data were obtained at a central radio frequency of 1380 MHz using a high-speed tape recorder that permitted coherent Nyquist sampling of 50 MHz of bandwidth in each of two polarizations. Using the high time resolution available from this voltage recording technique, we have studied a variety of single-pulse properties, many for the first time in a millisecond pulsar. We show that individual pulses are broad band, have pulse widths ranging from ∼ 10 (∼ …

Adaptation Space: Surviving Non-Maskable Failures, Crispin Cowan, Lois Delcambre, Anne-Francoise Le Meur, Ling Liu, David Maier, Dylan Mcnamee, Michael Miller, Calton Pu, Perry Wagle, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Some failures cannot be masked by redundancies, because an unanticipated situation occurred, because fault-tolerance measures were not adequate, or because there was a security breach (which is not amenable to replication). Applications that wish to continue to offer some service despite nonmaskable failure must adapt to the loss of resources. When numerous combinations of non-maskable failure modes are considered, the set of possible adaptations becomes complex. This paper presents adaptation spaces, a formalism for navigating among combinations of adaptations. An adaptation space describes a collection of possible adaptations of a software component or system, and provides a uniform way of …

The New Aleph Silicon Vertex Detector, D. Creanza, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The ALEPH collaboration, in view of the importance of effective vertex detection for the Higgs boson search at LEP 2, decided to upgrade the previous vertex detector. Main changes were an increased length (+/- 20 cm), a higher granularity for r phi view (50 mu m), a new preamplifier (MX7 rad hard chip), a polymide (upilex) fan-out on z side to carry the signals from the strips to the front-end electronics outside the fiducial region reducing consequently the passive material in the central region by a factor of two. The detector, the running experience and its performance will be described. …

An Atlas Of The Sand Hills, Ann S. Bleed, Charles A. Flowerday

Conservation and Survey Division

The Sand Hills region, approximately 19,300 square miles of sand dunes stretching 265 miles across Nebraska and into South Dakota, is the largest sand-dune area in the Western Hemisphere and is one of the largest grass-stabilized dune regions in the world.

The Price Of Clean Air: A Consideration Of Market Based Emissions Trading, Mark W. Miller

UNLV Theses, Dissertations, Professional Papers, and Capstones

Traditional regulatory approaches for environmental protection do not consider

the costs and benefits of the standards they impose. Further, imposing strict performance

standards on firms with heterogeneous control costs leads to an inefficient allocation of resources devoted to pollution control. This paper explores the use of emission allowance trading as a way to improve economic efficiency within the context of environmental protection. PM10 air pollution from sources within the Las Vegas Valley is used as the case study.

This paper found that an emission trading

program in this particular case study would not live up to the theoretical expectations. Although, …

Identification Of Subaqueous Groundwater Discharge To Large Scale Surface Water Bodies, East Tennessee Technology Park Site, Doe Oak Ridge Reservation, Oak Ridge, Tennessee, Thomas Frank Zondlo

Masters Theses

In East Tennessee, the Tennessee River and its tributaries cut across many of the sub-parallel strike valleys in the Valley and Ridge several times, including the karstic carbonate strike belts within them. The construction of dams along the Tennessee River and its tributaries, including the Clinch River, has increased the river stage between 5 and 20 m, which caused inundation of considerable areas. This also raised the baselevel for drainage, thus altering the groundwater regime within the valleys intersected by these rivers. The stud area addressed in this research includes an industrial facility situated on karstic carbonate bedrock which is …