Physical Sciences and Mathematics Commons^™

Is Screening Cargo Containers For Smuggled Nuclear Threats Worthwhile?, Jason R. W. Merrick, Laura A. Mclay

Statistical Sciences and Operations Research Publications

In recent years, Customs and Border Protection (CBP) has installed radiation sensors to screen cargo containers entering theUnited States. They are concerned that terrorists could use containers to smuggle radiological material into the country and carry out attacks with dirty bombs or a nuclear device. Recent studies have questioned the value of improving this screening system with new sensor technology. The cost of delays caused by frequent false alarms outweighs any reduction in the probability of an attack in an expected cost analysis. We extend existing methodology in three ways to demonstrate how additional factors affect the value of screening …

Magnetism In Zno Nanowire With Fe/Co Codoping: First-Principles Density Functional Calculations, S. Ghosh, Q. Wang, G. P. Das, Puru Jena

Physics Publications

Using first-principles density functional calculations, at both generalized gradient approximation (GGA) and GGA+U levels we have investigated the electronic structure and magnetic properties of Fe/Co codoped ZnO nanowire. Here we have addressed some of the key issues such as, the preferable sites that Fe/Co can occupy, the coupling mechanism, and role of defects in coupling. We found that the spin alignment between the transition-metal atoms depends on their location. When Fe and Co atoms are nearest neighbors on the outer surface of the nanowire along [0001] direction is the lowest energy configuration with ferrimagnetic (FiM) ground state. At GGA level …

Probing The Existence Of Energetically Degenerate Cluster Isomers By Chemical Tagging, Qian Wang, Qiang Sun, Puru Jena

Physics Publications

Current methods for identifying the ground state geometry of a cluster require synergy between theory and experiment. However, this becomes a difficult problem when the accuracy of the theoretical methods is not sufficient to distinguish between nearly degenerate isomers. Using density functional theory based calculations, we show that the near degeneracy between the planar and the cage structures can be lifted by tagging these with halogens and superhalogens moieties such as Cl and BO2. The energy of the planar Au16− isomer is lowered from 0.15 eV before tagging to 0.51–0.55 eV after tagging, thus providing a way to probe its …

Genome-Scale Metabolic Analysis Of Clostridium Thermocellum For Bioethanol Production, Seth B. Roberts, Christopher M. Gowen, J. Paul Brooks, Stephen S. Fong

Chemical and Life Science Engineering Publications

Background

Microorganisms possess diverse metabolic capabilities that can potentially be leveraged for efficient production of biofuels. Clostridium thermocellum (ATCC 27405) is a thermophilic anaerobe that is both cellulolytic and ethanologenic, meaning that it can directly use the plant sugar, cellulose, and biochemically convert it to ethanol. A major challenge in using microorganisms for chemical production is the need to modify the organism to increase production efficiency. The process of properly engineering an organism is typically arduous.

Results

Here we present a genome-scale model of C. thermocellum metabolism, iSR432, for the purpose of establishing a computational tool to study the …

Communications: Chain And Double-Ring Polymeric Structures: Observation Of Alnh3n+1− (N=4–8) And Al4h14, Xiang Li, Andrej Grubisic, Kit H. Bowen, Anil K. Kandalam, Boggavarapu Kiran, Gerd Gantefor, Puru Jena

Physics Publications

A pulsed arc discharge source was used to prepare gas-phase, aluminum hydride cluster anions, AlnHm−, exhibiting enhanced hydrogen content. The maximum number of hydrogen atoms in AlnHm− species was m=3n+1 for n=5–8, i.e., AlnH3n+1−, and m=3n+2 for n=4, i.e., Al4H14−, as observed in their mass spectra. These are the most hydrogen-rich aluminum hydrides to be observed thus far, transcending the 3:1 hydrogen-to-aluminum ratio in alane. Even more striking, ion intensities for AlnHm− species with m=3n+1 and m=3n+2 hydrogen atoms were significantly higher than those of nearby AlnHm− mass peaks for which m<3n+1, i.e., the ion intensities for AlnH3n+1− and for Al4H14− deviated from the roughly bell-shaped ion intensity patterns seen for most AlnHm−species, in which m ranges from 1 to 3n. Calculations based on density functional theory showed that AlnH3n+1− clusters have chain and/or double-ring polymericstructures.

2010 Annual Report Of The Water Quality Monitoring Project For The Water Quality Protection Program Of The Florida Keys National Marine Sanctuary, Joseph N. Boyer, Henry O. Briceño

SERC Research Reports

No abstract provided.

2010 Annual Report Of The Water Quality Monitoring Project For The Water Quality Protection Program Of The Florida Keys National Marine Sanctuary (Summary), Joseph N. Boyer, Henry O. Briceño

SERC Research Reports

No abstract provided.

Everglades Ridge, Slough, And Tree Island Mosaics: Year 2 Annual Report, Michael S. Ross, James B. Heffernan, Jay P. Sah, Pablo L. Ruiz, Adam A. Spitzig, Ewan Isherwood

SERC Research Reports

Status and history of the Ridge-Slough Mosaic The Florida Everglades is a large subtropical wetland with diverse hydrologic, edaphic, and vegetative characteristics. Historically, a significant portion of this system was a slow moving river originating from the Kissimmee River floodplain, flowing into the vast but shallow Lake Okeechobee, and draining south-southwest over extensive peatlands into Florida Bay (McVoy 2011). Human-induced alterations to the hydrologic regime, including reduction, stabilization, and impoundment of water flow through diversion and compartmentalization of water via canals and levees have degraded pre-drainage vegetation patterns and microtopographic structure (Davis and Ogden 1994, Ogden 2005, McVoy 2011). The …

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima. 2. Molecular Organization And Structural Stability, Andrea Scirè, Anna Marabotti, Maria Staiano, Luisa Iozzion, Matthew S. Luchansky, Bryan S. Der, Jonathan D. Dattelbaum, Fabio Tanfani, Sabato D'Auria

Chemistry Faculty Publications

ABC transport systems provide selective passage of metabolites across cell membranes and typically require the presence of a soluble binding protein with high specificity to a specific ligand. In addition to their primary role in nutrient gathering, the binding proteins associated with bacterial transport systems have been studied for their potential to serve as design scaffolds for the development of fluorescent protein biosensors. In this work, we used Fourier transform infrared spectroscopy and molecular dynamics simulations to investigate the physicochemical properties of a hyperthermophilic binding protein from Thermotoga maritima. We demonstrated preferential binding for the polar amino acid arginine …

Item Order Effects On Attitude Measures, Pei-Hua Chen

Electronic Theses and Dissertations

The purpose of this dissertation was to examine the effects of altered item order on attitude measures for both computerized adaptive and conventional survey formats. Based on items modified from a dissertation/thesis completion survey (Green & Kluever, 1997) with three scales, three survey versions were generated with items ordered by difficulty as hard-to-easy (H-E), easy-to-hard (E-H), and five medium trait level items presented first followed by randomly ordered items (M-R) for conventional survey format. Significant differences in item difficulty and item discrimination were found for two of the three scales. Differences in scale reliability were detected for the procrastination and …

Accelerated Lattice Boltzmann Method For Colloidal Suspensions Rheology And Interface Morphology, Hassan Farhat

Wayne State University Dissertations

ABSTRACT

ACCELERATED LATTICE BOLTZMANN MODEL FOR COLLOIDAL SUSPENSIONS RHEOLOGY AND INTERFACE MORPHOLOGY

by

HASSAN FARHAT

July 2010

Advisor: Dr. Singh Trilochan

Co-Advisor: Dr. Joon Sang Lee

Major: Mechanical Engineering

Degree: Doctor of Philosophy

Colloids are ubiquitous in the food, medical, cosmetic, polymer, water purification and pharmaceutical industries. Colloids thermal, mechanical and storage properties are highly dependent on their interface morphology and their rheological behavior.

Numerical methods provide a cheap and reliable virtual laboratory for the study of colloids. However efficiency is a major concern to address when using numerical methods for practical applications.

This work introduces the main building-blocks for …

A Bioarchaeological Study Of A Prehistoric Michigan Population: Fraaer-Tyra Site (20sa9), Allison June Muhammad

Wayne State University Dissertations

ABSTRACT

The Saginaw Valley Region has been the focus of Michigan archaeology for many decades. The Late Woodland period of the Saginaw Valley has been characterized as an area that prehistoric people abandoned as a permanent resident, but exploited seasonally during times of scarcity. Furthermore, the valley's resources were exploited by a diverse group of prehistoric peoples, both native to Michigan and those Mississippian `intruders' (Halsey 1976; Holman and Brashler 1999; Norder et al. 2003; Stothers 1999). Though previous studies of the Frazer-Tyra site (20SA9) have included ceramic and lithic analysis (Andrews 1995; Halsey 1976) and a study of mortuary …

Photodissociation Dynamics In Titan's Atmosphere, Welvidanalage Ruchira Silva

Wayne State University Dissertations

Photodissociation dynamics of molecules relevant to understanding Titan's atmosphere (diacetylene, cyanoacetylene and heptane isomers) are carried out under collisionless condition using the DC slice imaging technique. In diacetylene photodissociation, two-photon processes dominate at 243 nm and 212 nm whereas at 121.6 nm, a one-photon dissociation process dominates. Direct measurement of the lifetime of metastable triplet diacetylene confirms sub-microsecond lifetimes. Photodissociation of cyanoacetylene at 193.3 nm proceeds on the S1 potential energy surface with an exit barrier. In heptane photodissociation, the dissociation occurs on the ground state or low-lying triplet states with nonradiative electronic relaxation. Time-of-flight mass spectroscopy studies in this …

Wind For Schools: A Wind Powering America Project, National Renewable Energy Laboratory

Publications (E)

Energy is largely taken for granted within our society, but that perception is changing as the economic and environmental impacts of our current energy structure are more widely understood. The U.S. Department of Energy’s (DOE’s) Wind Powering America program sponsors the Wind for Schools Project to raise awareness in rural America about the benefits of wind energy while simultaneously developing a wind energy knowledge base in the United States to educate future leaders of our communities, states, and nation about the importance of renewable energy.

The three primary project goals of the Wind for Schools Project are to:

• Engage …

The Role Of Energy Storage With Renewable Electricity Generation, Paul Denholm, Erik Ela, Brendan Kirby, Michael Milligan

Publications (E)

Renewable energy sources, such as wind and solar, have vast potential to reduce dependence on fossil fuels and greenhouse gas emissions in the electric sector. Climate change concerns, state initiatives including renewable portfolio standards, and consumer efforts are resulting in increased deployments of both technologies. Both solar photovoltaics (PV) and wind energy have variable and uncertain (sometimes referred to as “intermittent”) output, which are unlike the dispatchable sources used for the majority of electricity generation in the United States. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction …

Analysis Of Hybrid Hydrogen Systems: Final Report, J. Dean, R. Braun, D. Munoz, M. Penev, C. Kinchin

Publications (E)

This project examined biomass pathways for hydrogen production and how they can be hybridized to support renewable electricity generation. The project considered many potential hybrid systems before narrowing the focus to two. The systems were studied in detail for process feasibility and economic performance. The best-performing system was estimated to produce hydrogen at a cost ($1.67/kg) within range of the Department of Energy target for central biomass-derived hydrogen production, while also providing value-added energy services to the electric grid.

2008 Solar Technologies Market Report, U.S. Department Of Energy

Publications (E)

This report focuses on the U.S. solar electricity market, including photovoltaic (PV) and concentrating solar power (CSP) technologies. The report provides an overview of global and U.S. installation trends. It also presents production and shipment data, material and supply chain issues, and solar industry employment trends. It also presents cost, price, and performance trends; and discusses policy and market drivers such as recently passed federal legislation, state and local policies, and developments in project financing. The final chapter provides data on private investment trends and near-term market forecasts.

Wind Powering America: Fy09 Activities Summary, National Renewable Energy Laboratory

Publications (E)

The Wind Powering America FY09 Activities Summary reflects the accomplishments of state Wind Working Groups, WPA programs at the National Renewable Energy Laboratory, and partner organizations.

Wind Power In Nevada, Hamedah Dhalai

Brookings Mountain West Publications

This bibliography compiles scholarly information and new reports on the topic of wind power in Nevada. As a senior at UNLV majoring in both Economics and French, I began this project in June 2010 in consultation with William E. Brown, Jr., director of planning and communications at Brookings Mountain West. This research topic interests me greatly, and I believe that expanded research and commercial development of alternative energy, including wind power, is essential to the growth and development of Nevada. My service as a Student Ambassador in the College of Business, a position that allows me to represent UNLV to …

On Coalgebras Over Algebras, Adriana Balan, Alexander Kurz

Engineering Faculty Articles and Research

We extend Barr’s well-known characterization of the final coalgebra of a Set-endofunctor as the completion of its initial algebra to the Eilenberg-Moore category of algebras for a Set-monad M for functors arising as liftings. As an application we introduce the notion of commuting pair of endofunctors with respect to the monad M and show that under reasonable assumptions, the final coalgebra of one of the endofunctors involved can be obtained as the free algebra generated by the initial algebra of the other endofunctor.

On Universal Algebra Over Nominal Sets, Alexander Kurz, Daniela Petrişan

Engineering Faculty Articles and Research

We investigate universal algebra over the category Nom of nominal sets. Using the fact that Nom is a full re ective subcategory of a monadic category, we obtain an HSP-like theorem for algebras over nominal sets. We isolate a `uniform' fragment of our equational logic, which corresponds to the nominal logics present in the literature. We give semantically invariant translations of theories for nominal algebra and NEL into `uniform' theories and systematically prove HSP theorems for models of these theories.

Bitopological Duality For Distributive Lattices And Heyting Algebras, Guram Bezhanishvili, Nick Bezhanishvili, David Gabelaia, Alexander Kurz

Engineering Faculty Articles and Research

We introduce pairwise Stone spaces as a natural bitopological generalization of Stone spaces—the duals of Boolean algebras—and show that they are exactly the bitopological duals of bounded distributive lattices. The category PStone of pairwise Stone spaces is isomorphic to the category Spec of spectral spaces and to the category Pries of Priestley spaces. In fact, the isomorphism of Spec and Pries is most naturally seen through PStone by first establishing that Pries is isomorphic to PStone, and then showing that PStone is isomorphic to Spec. We provide the bitopological and spectral descriptions of many algebraic concepts important for the study …

Dynamics Of Porous Silicon Formation By Etching In Hf + V2o5 Solutions, Kurt W. Kolasinski, Justin B. Hartline, Bryan T. Kelly, Julia Yadlovskiy

Chemistry Faculty Publications

No abstract provided.

Influence Of Coulomb Interactions On Emission Dynamics In Semiconductor Quantum Dot Systems, Kamil Gradkowski

Theses

In this thesis the novel self-assembled quantum dots based on GaSb/GaAs technology are investigated for the possible application in the near- and mid-infrared, i.e. telecommunication networks, solar cells, gas sensors and imaging systems. These heterostructures exhibit a type-Il band alignment, which means that one species of carriers is confined to the dot, while the other is outside in the surrounding matrix. This physical separation of carriers leads to profound Coulomb interactions, which makes the optical properties of these structures dependent on the injected charge density. The relationship between two of those properties, the emission energy and transition probability, leads to …

Rademacher-Type Formulas For Partitions And Overpartitions, Andrew Sills

Department of Mathematical Sciences Faculty Publications

A Rademacher-type convergent series formula which generalizes the Hardy-Ramanujan-Rademacher formula for the number of partitions of n and the Zuckerman formula for the Fourier coefficients of ϑ4_0 | τ_−1 is presented.

Atmospheric Effects On The Propagation Of Mmw And Sub-Mmw Radiation, John S. Cetnar

Browse all Theses and Dissertations

This thesis is a study of the propagation of millimeter wavelength (MMW) and submillimeter wavelength (sub-MMW) electromagnetic radiation (a.k.a. THz radiation) through the Earth's atmosphere. THz radiation is electromagnetic radiation that exists between the microwave and far infrared regions of the electromagnetic spectrum. It is nonionizing radiation but can penetrate through materials that are opaque to visible light so therefore has many new and useful applications. Unfortunately, THz radiation is heavily attenuated by the Earth's atmosphere as it propagates through it. This therefore represents a challenge to communications and sensing applications at millimeter and sub-millimeter wavelengths. In this work, the …

Towards The Total Synthesis Of Haplomyrtin, Nora Ellen Hunter

Browse all Theses and Dissertations

Haplomyrtin, a 1-aryl-2,3-naphthalide lignan obtained from Turkish Haplophyllum myrtifolium and Haplophyllum telephioides offers a number of synthetic challenges with the incorporation of two aromatic hydroxyl groups at positions C4 and C7 on the naphthalene ring system and regiospecific condensation of the γ-lactone ring. Improvements towards the total synthesis of haplomyrtin were pursued with commercially available vanillin and piperonal in a total of 8 separate steps. All steps have excellent reproducibility. This strategy includes bromination of protected vanillin to yield 2-(4-(4-methoxybenzyloxy)-2-bromo-5-methoxyphenyl)-1,3-dioxolane and 2-(4-(benzyloxy)-2-bromo-5-methoxyphenyl)-1, 3-dioxolane in 48% and 88% yield respectively, and incorporation of the fully functionalized pendant aryl ring through a …

Surveillance In A Smart Home Environment, Ryan Stewart Patrick

Browse all Theses and Dissertations

A system for assisting the elderly in maintaining independent living is currently being designed. When mature, it is expected that this system will have the ability to track objects that a resident may lose periodically, detect falls within the home, and alert family members or health care professionals to abnormal behaviors.

This thesis addresses the early stages of this system's development. It presents a survey of the work that has previously been completed in the area of surveillance within a home environment, information on the physical characteristics of the system that is being designed, early results related to this system, …

Mercury Speciation In Temperate Tree Foliage, Melissa Danielle Tabatchnick

Browse all Theses and Dissertations

Cycling of mercury (Hg) and monomethylmercury (MMHg) in forest ecosystems can affect exposures of terrestrial and aquatic wildlife within the watershed. Litterfall has been posited to be a major source of MMHg and total Hg to the forest floor; however, the origin of MMHg associated with tree foliage is largely unknown. I tested the hypothesis that leaf MMHg would be controlled by root uptake and thereby proportional to levels in soil. Fresh leaves and associated soil samples were sampled from nine tree species (deciduous and coniferous) at 30 locations spanning a 1145 km2 area in southwest Ohio, a region presumed …

Prognosis: A Wearable System For Health Monitoring Of People At Risk, Alexandros A. Pantelopoulos

Browse all Theses and Dissertations

Wearable Health Monitoring Systems (WHMS) have drawn a lot of attention from the research community and the industry during the last decade. The development of such systems has been motivated mainly by increasing healthcare costs and by the fact that the world population is ageing. In addition to that, RandD in WHMS has been propelled by recent technological advances in miniature bio-sensing devices, smart textiles, microelectronics and wireless communications techniques. These portable health systems can comprise various types of small physiological sensors, which enable continuous monitoring of a variety of human vital signs and other physiological parameters such as heart …