Physical Sciences and Mathematics Commons^™

Acknowledgements, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Redox-Magnetohydrodynamic (Mhd) Microfluidics: Fundamentals, Optimization, And Applications To Analytical Chemistry, Melissa Christine Weston

Graduate Theses and Dissertations

Microfluidic systems are of great interest in analytical chemistry for the development of lab-on-a-chip devices. This dissertation describes fundamental investigations of magnetohydrodynamics with added redox species (redox-MHD) as a new microfluidic approach for use in analytical applications. Redox-MHD is attractive because it offers a unique combination of desirable features that are otherwise only available separately with individual micropumps. Redox-MHD is compatible with aqueous and nonaqueous solutions, does not require moving parts, easily reverses flow direction, and requires only low voltages. An ion flux is generated from the oxidation or reduction of an electroactive species at specific locations by activated electrodes …

Linkage Of Asteroids And Meteorites By The Study Of Terrestrial Analogs, Daniel Robert Ostrowski

Graduate Theses and Dissertations

Asteroids are one group of the bodies that can provide insights into the origin and early history of the solar system. Asteroids are considered to be fairly pristine, with alterations only occurring to their surface from the space environment. Studying them provides opportunities to learn about the primordial solar system, its materials, and processes and how it evolved into the current condition. Many asteroids have been discovered, but few have their surface compositions determined. The C and X complexes provide a difficulty in determination because their near infrared spectrum is featureless.

The C asteroids have been long associated with the …

The Role Of Sulfur In Biomineralization: Argopecten Irradians And The Impact Of Ocean Acidification, Bryanna Joy Broadaway

Graduate Masters Theses

The burning of fossil fuels, and other natural processes, has led to an increase of carbon dioxide (CO₂) in the atmosphere. The equilibration of atmospheric CO₂ with surface waters causes the ocean pH to decrease from the current value of 8.1. Evidence suggests that as the ocean becomes more alkaline, organisms such as the bay scallop, Argopecten irradians¸will become more stressed due to increased energy demands to maintain shell deposition and growth. This stress, as hypothesized here, may cause the deposition of S-bearing organic macromolecules to aid in mineralization as well as the potential for sulfate …

Shovelnose Sturgeon Age And Growth Characteristics And Fish Community Characteristics Of The Lower Platte River And Missouri River Near Nebraska, Tara L. Anderson

School of Natural Resources: Dissertations, Theses, and Student Research

There have been documented widespread losses of freshwater biodiversity over the past several decades. Many of these losses may be due to anthropogenic causes such as habitat alterations, pollution, and overharvest. Shovelnose sturgeon may also be influenced by anthropogenic causes and have experienced declines in population abundance near Nebraska. My objectives were to first to describe the age, growth and mortality of shovelnose sturgeon found in the lower Platte River (LPR). Second, I quantitatively evaluated similarities and differences between the Missouri River (MR) and the LPR fish community composition (presence-absence of species) and structure (abundance of species). We used trammel …

Ultrasonic Activation Of Triacetone Triperoxide, Latravia R. Dobson

Department of Chemistry: Dissertations, Theses, and Student Research

Triacetone triperoxide (TATP) is an organic peroxide that has received widespread attention in recent years. TATP is a ketone peroxide with a high active oxygen content. It is relatively shock sensitive, with explosive decomposition easily initiated, and is therefore considered a primary explosive. However, TATP is also a powerful explosive possessing about 83 % of the power of TNT. TATP can be prepared quickly and easily from inexpensive household chemicals in the absence of any specialized facilities, making it the explosive of choice for modern day terrorists. TATP poses a major challenge for security and law enforcement services around the …

Synthesis And Catalytic Activity Of Nanostructured Cerium Oxide, Neil J. Lawrence

Department of Chemistry: Dissertations, Theses, and Student Research

Cerium oxide (ceria, CeO_2-x where x is 0 to 0.5) has been one of the most widely used heterogeneous catalysts particularly in three way catalytic converters. Most of the catalytic traits can be attributed to two properties of ceria: first, the high mobility and storage capacity of oxygen within the lattice; second, the ease with which cerium changes between Ce³⁺ and Ce⁴⁺ states. These properties, combined with the abundance of cerium on earth, make ceria a low-cost highly effective alternative to noble metal catalysts. Recent research has been focused on the nanoscale properties of ceria.

The effect …

Characteristics And Stability Of Oxide Films On Plutonium Surfaces, Harry Guillermo García Flores

Department of Chemistry: Dissertations, Theses, and Student Research

The oxidation of plutonium (Pu) metal continues to be an area of considerable activity. The reaction characteristics have significant implications for production use, storage, and disposition of this radiological material. Developing an accurate physical model of the structures, oxidation states, and oxygen concentration gradients present during oxidation are essential to understanding this process. Traditionally, the stable oxides of Pu have been thought to be plutonium sesquioxide (Pu₂O₃, O/Pu = 1.5, Pu³⁺) and plutonium dioxide (PuO₂, O/Pu = 2.0, Pu⁴⁺), existing in a layered structure on Pu metal. Many of the …

I, A New Synthetic Approach To The Synthesis Of N-(Phosphonoacetyl)-L-Ornithine. Ii, The Influence Of Pyridine On The Ozonolysis Of Alkenes, Bradley M. Johnson

Department of Chemistry: Dissertations, Theses, and Student Research

Part I. The use of chemical inhibitors to manipulate the level of amino acids in cells has proven to be invaluable in the mechanistic study of gene expression in bacteria and fungi. Here we present a new approach to the synthesis of δ‐N‐ (phosphonoacetyl)‐L‐ornithine (PALO), a potent ornithine transcarbamylase inhibitor, using a new amino acid protecting group, 9‐borabicyclononane (9‐BBN). Starting from commercially available reagents and utilizing mild reaction conditions, we were able to form PALO in fewer synthetic steps and in greater yields than previous attempts.

Part II. Ozonolysis is widely used to transform alkenes into oxygen‐rich functional groups (e.g.– …

Abrupt Longitudinal Magnetic Field Changes In Flaring Active Regions, G. J.D. Petrie, Jeffrey J. Sudol

Physics & Engineering Faculty Publications

No abstract provided.

Oil And Gas Management In Nigeria: Lessons For Ghana, Omolara O. Akanji Mrs.

Bullion

This paper is to discuss the oil and gas management in Nigeria: Lessons for Ghana. The paper is structured into five parts with part 1 being the introduction while part 2 scoops the literature on the economics of natural resources and its management globally. Part 3 will situate the Nigeria's multifaceted crisis of oil and gas governance and all related issues. Part 4 will sieve out the lessons for Ghana while part 5 summarizes and concludes the paper.

Technology Capacity Development Through Oss Implementation: The Case Of Public Higher Education Institutions In Ethiopia, Nigussie Tadesse Mengesha

The African Journal of Information Systems

The Open Source Software (OSS) literature gives little attention to the study and practice of domain specific end-user OSS implementation in general and in the public sector of developing countries (DCs) in particular. This paper, however, investigates the trajectories of two OSS-based information systems (IS) implementation projects in a developing country (DC) context with the aim to uncover the practice-based learning and resource sharing evident among locally situated and globally dispersed developers and users. The result of the interpretative case study research shows that the OSS philosophy and practice of software development, implementation and ownership, facilitates for the emergence of …

On The Perfection Of Broccoli: Talking To Ed Brush, Lee Torda

Bridgewater Review

No abstract provided.

A Genetic Algorithm For Multiobjective Hard Scheduling Optimization, Elías Niño, Carlos Ardila, Alfredo J. Perez, Yexid Donoso

Computer Science Faculty Publications

This paper proposes a genetic algorithm for multiobjective scheduling optimization based in the object oriented design with constrains on delivery times, process precedence and resource availability. Initially, the programming algorithm (PA) was designed and implemented, taking into account all constraints mentioned. This algorithm’s main objective is, given a sequence of production orders, products and processes, calculate its total programming cost and time.
Once the programming algorithm was defined, the genetic algorithm (GA) was developed for minimizing two objectives: delivery times and total programming cost. The stages defined for this algorithm were: selection, crossover and mutation. During the first stage, the …

Notes From The Director, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Mcnair Scholars Program, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Friends Of The Library Mcnair Scholarship Awards, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

Biochemical Characterization Of Theromin, A Novel Leech Inhibitor, And The Interaction Between The Fourth Metalbinding Domain Of Wilson Disease Protein And Its Copper(I) Chaperone Hah1, Brian A. Zeider

Dissertations

Theromin, a novel thrombin inhibitor from the leech Theromyzon tessulatum, has been shown to be the strongest inhibitor to date. There has been a lot of attention on direct thrombin inhibitors as a much more efficient drug for anticoagulation therapy. One main reason for the need of strong direct thrombin inhibitors is that the current therapy, heparin, causes alternative clotting events in some patients where antibodies are made to the heparin/thrombin complex and causes clots to occur by different methods. Recently there has been a strong inhibitor from a leech used, hirudin, that can inhibit with a K_{i …}

Geochemical, Isotopic, And U-Pb Geochronologic Investigations Of Intrusive Basement Rocks From The Wallowa And Olds Ferry Arc Terranes, Blue Mountains Province, Oregon-Idaho, Gene Alan Kurz

Boise State University Theses and Dissertations

Late Paleozoic to Mesozoic arc terranes comprising the Blue Mountains Province of northeastern Oregon and western Idaho are poorly understood in terms of the timing and duration of recorded magmatism and deformation. Intrusive basement rocks of the Wallowa and Olds Ferry arc terranes are investigated using a combination of highprecision U-Pb geochronology, radiogenic isotope and trace element geochemistry, and structural geology to help constrain their tectonomagmatic evolution and to provide a better understanding for the accretionary history of the Blue Mountains Province.

The Cougar Creek Complex is a compositionally diverse intrusive complex interpreted as the mid-crustal portion of the Wallowa …

Inner-Shell Photodetachment Of Transition Metal Negative Ions, Ileana Dumitriu

Dissertations

This thesis focuses on the study of inner-shell photodetachment of transition metal negative ions, specifically Fe¯ and Ru¯. Experimental investigations have been performed with the aim of gaining new insights into the physics of negative atomic ions and providing valuable absolute cross section data for astrophysics. The experiments were performed using the X-ray radiation from the Advanced Light Source, Lawrence Berkeley National Laboratory, and the merged-beam technique for photoion spectroscopy.

Negative ions are a special class of atomic systems very different from neutral atoms and positive ions. The fundamental physics of the interaction of transition metal negative ions with photons …

F5c: A Variant Of Faugere's F5 Algorithm With Reduced Gröbner Bases, Christian Eder, John E. Perry

Faculty Publications

The F5 algorithm for computing Gröbner bases achieves a high level of efficiency through the careful analysis of signatures assigned to each computed polynomial. However, it computes and uses many polynomials that turn out to be redundant. Eliminating these redundant polynomials is a non-trivial task, because they correspond to signatures required for reduction. This paper revisits the theory underlying F5 and describes F5C, a new variant that prunes redundant polynomials, then re-computes signatures to preserve correctness. This strategy successfully reduces both overhead and execution time. (C) 2010 Elsevier Ltd. All rights reserved.

Confidence Intervals And Tests On The Difference Of Means Of Two Delta Distributions, Karen Grace Villarente Rosales

Dissertations

Various research fields produce data that are lognormally distributed and inflated with zero values. This type of data follows a delta distribution. In this study, we want to extensively investigate different interval and hypothesis testing methods for comparing the means of two delta populations to see which methods are optimal under different conditions of the populations.

For confidence intervals, existing MVUE methods are extended to two sample cases and compared to classical and two proposed robust methods. We investigated the performance of the classical Student's t, Welch t, and Wilcoxon-based interval to see if these methods really perform badly on …

The K-Cores Of A Graph, Allan Bickle

Dissertations

Full abstract attached as supplemental file.

New Exact Solutions Of Some Nonlinear Partial Differential Equations By The First Integral Method, Nasir Taghizadeh, Mohammad Mirzazadeh, Foroozan Farahrooz

Applications and Applied Mathematics: An International Journal (AAM)

The first integral method is an efficient method for obtaining exact solutions of nonlinear partial differential equations. The efficiency of the method is demonstrated by applying it for two selected equations. This method can be applied to nonintegrable equations as well as to integrable ones.

Kinematics And Vorticity In Kangmar Dome, Southern Tibet: Testing Midcrustal Channel-Flow Models For The Himalaya, Tom Wagner, Jeffrey Lee, Bradley R. Hacker, Gareth Seward

All Faculty Scholarship for the College of the Sciences

Kinematic, kinematic vorticity (W_m), and deformation temperature analyses were completed to test the hypothesis that midcrustal rocks exposed in the core of the Kangmar gneiss dome, southern Tibet record ductile deformation patterns of a “frozen” segment of a southward flowing midcrustal channel. Microscopic and mesoscopic kinematic indicators exhibit a downward transition from a subequal mix of top-north and top-south shear in garnet zone rocks to dominantly top-north shear in staurolite/kyanite zone and deeper rocks. Kinematic vorticity values indicate an increase in pure shear component with depth from ∼48% pure shear in chloritoid zone rocks through ∼62% in …

The Influence Of Nanoporous Crystalline Structure On Low Molecular Weight Mass Transport In Syndiotactic Polystyrene, Justin Paul Brandt

Dissertations

Solid-state structure, crystalline morphology, crystallization kinetics, thermal, free volume, and gas transport properties of semicrystalline syndiotactic polystyrene (sPS) and ethylene vinyl alcohol copolymers (EVOH) have been investigated. Solid-state structure of sPS after crystallization from the melt and glassy state was examined by differential scanning calorimetry (DSC), density and wide angle x-ray diffraction analysis (WAXD). The measurements confirmed low density of syndiotactic polystyrene crystalline forms, which in the case of α and δe was smaller and in the case of β and γ crystalline forms was slightly larger than the density of the glassy amorphous sPS. Positron annihilation lifetime spectroscopy (PALS) …

The Update, December 2010, University Of Northern Iowa. College Of Humanities, Arts And Sciences.

Update

Inside this issue:

-- American Chemical Society, a student affiliate group
-- Department News
-- Iowa Writing Project
-- UNI School of Music to Host 50th Anniversary Celebration: Varsity Men's Glee Club Christmas Variety Shows
-- Communication Studies: Student Showcased on the Jay Leno Show
-- Dmitri Vorobiev: An All Beethoven Recital Series
-- Student Spotlight: Philosophy: Joel Anderson
-- Student Spotlight: World Religions: Elizabeth Wiedenheft
-- Student Spotlight: Industrial Technology: Hannah Loan
-- UNI Students attend and participate in sixth Annual Multicultural Conference
-- Student Spotlights Continued
-- School of Music Events
-- UNI Forensics
-- Communication Studies Students …

Robust Interval Estimation Of A Treatment Effect In Observational Studies Using Propensity Score Matching, Scott F. Kosten

Dissertations

Estimating the treatment effect between a treatment group and a control group in an observational study is a challenging problem in statistics. Without random assignment of subjects, there are likely to be differences between the treatment group and control group on a set of baseline covariates. If one of these baseline covariates is correlated to the response variable, then the difference in sample means between the groups is likely to be a biased estimate of the true treatment effect.

Propensity score matching has become an increasingly popular strategy for reducing bias in estimates of the treatment effect. This reduction in …

Dielectronic Recombination For Aluminum-Like Ions And Photoabsorption Cross Sections For Magnesium Ions At The K-Edge, Shahin Ahmed Abdel-Azim Abdel Naby

Dissertations

Accurate and reliable recombination data are needed for modeling the ions in the finitedensity plasmas that may take place in solar flares and in divertors of magnetically confined fusion devices such as the International Thermonuclear Experimental Reactor (ITER). Dielectronic recombination (DR) is the dominant recombination mechanism in photoionized and collisionally-ionized plasmas. DR rate coefficients for M-shell argon ions have been calculated using a configuration-average approach. DR rate coefficients for the aluminumlike isoelectronic sequence are instead calculated using the state-of-the-art multiconfiguration Breit-Pauli (MCBP) atomic structure and collision code AUTOSTRUCTURE. Good agreement is obtained with the measurements from the Heidelberg heavy-ion Test …

Heavy Metal Concentrations In Water And Surface Sediments Of Wilgreen Lake, Madison County, Kentucky, Chad Von Gruenigen, Walter S. Borowski

EKU Faculty and Staff Scholarship

Heavy metal pollution remains problematic in natural waters, particularly for localities near plausible anthropogenic sources. We assayed the level of heavy metals in surface waters and within surface sediments of Wilgreen Lake, whose watershed drains industrial, urban, agricultural, and residential areas near Richmond, Kentucky. Water samples were treated according to Environmental Protection Agency (EPA) protocols and digested with trace-metal-grade nitric and hydrochloric acids. Sediment samples were collected with a grab sampler and digested using established EPA procedures with hydrogen peroxide and trace-metal-grade nitric acid. Both water samples and sediment samples were sent to Activation Laboratories for analysis, and were measured …