Physical Sciences and Mathematics Commons^™

Development Of An Automated Detection System For Nitrite In Aquatic Environments, Tim Schierenbeck

Theses and Dissertations

The main objective of the project is to develop an automated nitrite sensor for use in aquatic environments, and more specifically for use in recirculating aquaculture systems (RAS), where monitoring can help sustain a controlled environment, protect against nitrite intoxication, and promote fish health. Detecting nitrite manually with semi-quantitative colorimetric test kits, although inexpensive and simple, is prone to inter-user variability and poor sensitivity. An automated nitrite sensor has potential to provide higher resolution measurements at both concentration and time scales and can serve as a research tool for the study of filtration systems essential in maintaining a healthy RAS …

Rational Design Of Cathode Materials For High Performance Lithium-Sulfur Batteries, Xi Chen

Theses and Dissertations

Sulfur, one of most promising cathode candidates for next-generation lithium ion batteries, shows a limited cycling performance due to its shuttling effect, low conductivity, self-discharge and volume expansion during lithiation and delithiation process. According to the operation principles, failure mechanism, and recent progress on lithium-sulfur batteries, here we developed several scalable and rational synthesis methods for high performance cathode materials. We dissolved commercial sulfur to anhydrous ethylenediamine (EDA) to form an EDA-S precursor, and then we reduced the sulfur particles size at conductive carbon black substrate. The 70% theoretical capacity of sulfur cathode battery was obtained. We also melted commercial …

Addressing Instability Issues In Microgrids Caused By Constant Power Loads Using Energy Storage Systems, Eklas Hossain

Theses and Dissertations

Renewable energy sources, the most reasonable fuel-shift taken over the naturally limited conventional fuels, necessarily deal with the self-functional microgrid system rather than the traditional grid distribution system. The study shows that the microgrid system, a comparatively low-powered system, experiences the challenge of instability due to the constant power load (CPL) from many electronic devices such as inverter-based systems. In this dissertation, as a methodical approach to mitigate the instability complication, AC microgrid stability is thoroughly investigated for each and every considerable parameter of the system. Furthermore, a specific loading limit is depicted by evaluating the stability margin from the …

Seasonal And Spatial Variations In Chemical Composition And Fluxes Of Dissolved Organic Matter And Nutrients In The Lower Milwaukee River, Tarek A. Teber

Theses and Dissertations

Physical, chemical and biological processes directly influence the transport, composition, and fluxes of dissolved organic matter (DOM) in river watersheds. Changes in the abundance and composition of DOM and nutrients (P&N) in the watershed should reflect changes in hydrological cycle, effluent discharge, land-use and land-cover, and anthropogenic activities in the river basin, especially in rivers that run through metropolitan areas such as the Milwaukee River. Despite the importance of DOM to ecosystem health and function, a literature search to date finds no comprehensive accounting of DOM in the Milwaukee River. To examine DOM dynamics, monthly water samples were collected between …

Analysis Of The Run-To-Run Variability Within The Namm Forecasts For The Northeast U.S. Blizzard Of 8-9 February 2013, Kaitlyn Heinlein

Theses and Dissertations

On 8-9 February 2013, a strong extratropical cyclone brought historic winter storm conditions to the Northeast United States with a swath of one to three feet of snow falling across much of New England, with isolated pockets exceeding three feet across south-central Connecticut. Given the high socioeconomic impact that resulted from this blizzard, this study focuses on the run-to-run variability in operational model (North American Mesoscale model; NAM) forecasts leading up to the event. These forecasts, initialized forty-eight hours or less from the start of the event, showed two instances indicating a substantial shift in the expected impact. The first …

Restricting A Representation To A Principally Embedded Sl(2) Subalgebra, Hassan Lhou

Theses and Dissertations

Fix n>2. Let s be a principally embedded sl(2)-subalgebra in sl(n). A special case of work by Jeb Willenbring and Gregg Zuckerman implies that there exists a positive integer b(n) such that for any finite dimensional sl(n)-representation, V, there exists an irreducible s-representation embedding in V with dimension at most b(n). We prove that the best possible value for the bound is b(n)=n.

Transient Control Of Synchronous Machine Active And Reactive Power In Micro-Grid Power Systems, Luke Gerard Weber

Theses and Dissertations

There are two main topics associated with this dissertation. The first is to investigate

phase–to–neutral fault current magnitude occurring in generators with multiple zero–sequence

current sources. The second is to design, model, and tune a linear control system for oper-

ating a micro–grid in the event of a separation from the electric power system.

In the former case, detailed generator, AC8B excitation system, and four–wire electric

power system models are constructed. Where available, manufacturers data is used to

validate the generator and exciter models. A gain–delay with frequency droop control

is used to model an internal combustion engine and governor. …

An Exponential Time Differencing Scheme With A Real Distinct Poles Rational Function For Advection-Diffusion Reaction Equations, Emmanuel Owusu Asante-Asamani

Theses and Dissertations

A second order Exponential Time Differencing (ETD) scheme for advection-diffusion reaction systems is developed by using a real distinct poles rational function for approximating the underlying matrix exponential. The scheme is proved to be second order convergent. It is demonstrated to be robust for reaction-diffusion systems with non-smooth initial and boundary conditions, sharp solution gradients, and stiff reaction terms. In order to apply the scheme efficiently to higher dimensional problems, a dimensional splitting technique is also developed. This technique can be applied to all ETD schemes and has been found, in the test problems considered, to reduce computational time by …

An Evaluation Of Paleomagnetic Techniques To Determine Emplacement Temperatures Of Pyroclastic Density Currents At Mount St. Helens, Devin Gerzich

Theses and Dissertations

During a volcanic eruption, pyroclastic density currents (PDCs) deposit new pumice and ash and rip out and transport lithic fragments from past eruptions. Magnetic minerals in the lithic fragments, such as titanomagnetite, may be partially or completely remagnetized, depending on their emplacement temperature with respect to their Curie and blocking temperatures. By finding the temperature at which this remagnetized overprint is removed, the emplacement temperature of the pyroclastic flow is estimated. This method assumes that the rock magnetic properties that govern magnetic unblocking are constant given a specific magnetic mineral composition, but recent studies demonstrate that Curie temperatures (Tc) in …

Nonlocal Debye-Hückel Equations And Nonlocal Linearized Poisson-Boltzmann Equations For Electrostatics Of Electrolytes, Yi Jiang

Theses and Dissertations

Dielectric continuum models have been widely applied to the study of aqueous electrolytes since the early work done by Debye and Hückel in 1910s. Traditionally, they treat the water solvent as a simple dielectric medium with a permittivity constant without considering any correlation among water molecules. In the first part of this thesis, a nonlocal dielectric continuum model is proposed for predicting the electrostatics of electrolytes caused by any external charges. This model can be regarded as an extension of the traditional Debye Hückel equation. For this reason, it is called the nonlocal Debye-Hückel equation. As one important application, this …

Existence Of The Mandelbrot Set In The Parameter Planes Of Certain Rational Functions, Alexander Jay Mitchell

Theses and Dissertations

In complex dynamics we compose a complex valued function with itself repeatedly and

observe the orbits of values of that function. Particular interest is in the orbit of critical

points of that function (critical orbits). One famous, studied example is the quadratic

polynomial Pc(z) = z^2 +c and how changing the value of c makes a difference to the orbit of the critical point z = 0. The set of c values for which the critical orbit is bounded is called

the Mandelbrot set.

This paper studies rational functions of the form Rn;a;c(z) = z^n + a/z^n + c and …

Sedimentology Of The Mid-Carboniferous Basal Fill Of The Olta Paleovalley, Eastern Paganzo Basin, Argentina, Levi Darwin Moxness

Theses and Dissertations

As global climate transitioned from the icehouse of the Late Paleozoic Ice Age (LPIA) to greenhouse conditions of the Late Permian, glaciers vanished across Gondwana; however, not all ice centers responded synchronously. The Paganzo basin, northwestern Argentina, was geographically adjacent to significant mid-Carboniferous ice centers that disappeared notably earlier than ice over much of Gondwana. Confining the extent of glacial ice during the LPIA and resolving the timing of its disappearance is of particular interest as this dramatic climatic transition is the closest analogue in Earth history to late Cenozoic climate change, potentially aiding in anticipating the response of modern …

Domain Decomposition Based Hybrid Methods Of Finite Element And Finite Difference And Applications In Biomolecule Simulations, Jinyong Ying

Theses and Dissertations

The dielectric continuum models, such as Poisson Boltzmann equation (PBE), size modified PBE (SMPBE), and nonlocal modified PBE (NMPBE), are important models in predicting the electrostatics of a biomolecule in an ionic solvent. To solve these dielectric continuum models efficiently, in this dissertation, new finite element and finite difference hybrid methods are constructed by Schwartz domain decomposition techniques based on a special seven-box partition of a cubic domain. As one important part of these methods, a finite difference optimal solver --- the preconditioned conjugate gradient method using a multigrid V-cycle preconditioner --- is described in details and proved to have …

Development Of Cellular High Throughput Assays To Determine The Electrophysiological Profile Of Gaba(A) Receptor Modulators For Neurology And Immunology, Nina Yina Yuan

Theses and Dissertations

Gamma (γ) -aminobutyric acid (GABA) is the major inhibitory neurotransmitter found in

the mammalian central nervous system. Its effect stems from its ability to cause the opening of ion channels which causes an influx of negatively charged chloride ions or an efflux of positively charged potassium ions. This hyperpolarization of the neuron lowers the threshold for neuronal firing. This has an overall inhibitory effect on neurotransmission, decreasing the excitability of the neuron and diminishing the likelihood of a successful action potential occurring. There are two classes of GABA receptor: ligand-gated GABAA receptor (GABAAR) and metabotropic GABAB receptor (GABABR). The GABAAR …

Assessing The Remanufacturability Of Office Furiniture: A Multi-Criteria Decision Making Approach, Po-Hsun Chen

Theses and Dissertations

While the average life cycle of consumer goods is continuously decreasing, the amount of used product at their end-of-life (EOL) is accumulating fast at and at the same pace. Most EOL products end up in landfills, and many of which are not biodegradable. These two challenges have necessitated renewed global interest in product EOL management strategies by manufacturers, third party companies, consumers and governments. Remanufacturing is one of the EOL strategies which is highly environmental-friendly. Additionally, remanufacturing is seen as one of the highly profitable re-use business strategies. The selling price of remanufactured products is usually about 50—80% of a …

Molecular Recognition In Water: Design, Synthesis, And Characterization Of Rigid Molecular Receptors And Enzymatic Mechanistic Probes, Robert William Hoppe

Theses and Dissertations

Molecular recognition can be defined as a selective and reversible binding between two or more molecules through non-covalent interactions. Multiple weakly attractive intermolecular forces work in concert to achieve selectivity in association. Such discrimination is critical to the physiological processes of catalysis, transport, antigen recognition, and storage. To better understand this phenomenon, acyclic synthetic molecular receptors also known as “molecular tweezers” were made to study the inclusion of small molecule guests from water. Three anionic tweezers derivatives with syn¬- cofacial orientation were constructed from a 1,2:4,5-bis-Trӧger’s Base skeleton that differed in the amount and distribution of negative charge about the …

The Role Of Proteome In Cellular Zn2+ Trafficking And In The Ability Of The Fluorescent Zinc Sensors To Image Intracellular Zn2+, Mohammad Rezaul Karim

Theses and Dissertations

Zinc is an essential biological trace metal used in as many as 3000 Zn-proteins, about 10% of the eukaryotic proteome, as either a structural constituent or a catalytic cofactor. These proteins include the zinc fingers, the most prevalent transcription factors that bind a wide range of gene promoters and thus regulate gene expression. A eukaryotic cell contains several hundred micromolar of Zn2+- almost all of it is bound to specific Zn-proteins. Recently, Zn2+ has been reported to serve as a regulatory signal and a neurotransmitter, suggesting that there also exists a dynamic Zn2+ pool in cells. These findings led to …

Structural And Functional Characterization Of Acetoacetate Decarboxylase-Like Enzymes, Lisa Mueller

Theses and Dissertations

The acetatoacetate decarboxylase-like superfamily (ADCSF) is a largely unexplored group of enzymes that may be a potential source of new biocatalysts. Bioinformatic analysis has grouped these approximately 2000 enzymes into seven different families based on comparison of predicted active site residues. To date, only the prototypical ADCs (Family I) that catalyze the decarboxylation of acetoacetate have been studied. Analysis of gene context suggests that Family V contains predominantly enzymes predicted to be involved in secondary metabolism. On average, these share about 20% sequence identity to the true ADCs. To learn more about the diversity of chemistries performed by members of …

The Synthesis Of Fluorescent 3, 6-Dihydroxyxanthones: A Route To Substituted Fluoresceins, Surajudeen Omolabake

Theses and Dissertations

ABSTRACT

THE SYNTHESIS OF FLUORESCENT 3, 6-DIHYDROXYXANTHONES:

A ROUTE TO SUBSTITUTED FLUORESCEIN

by

Surajudeen Omolabake

University of Wisconsin-Milwaukee, 2016

Under the Supervision of Professor Alan W Schwabacher

Xanthones belong to the family of compounds of the dibenzo-γ-pyrone framework. Naturally occurring xanthones have been reported to show a wide range of biological and medicinal activities including antifungal,19 antimalarial,20 antimicrobial,21 antiparasitic,22 anticancer,23 and inhibition of HIV activity in cells.24 Xanthones have also been used as a turn on fluorescent probe for metal ions,32 including use as pH indicators, metal ion sensors, in molecular biology, medicinal chemistry and in the construction of other …

An Energy Efficient, Load Balancing, And Reliable Routing Protocol For Wireless Sensor Networks, Kamil Samara

Theses and Dissertations

AN ENERGY EFFICIENT, LOAD BALANCING, AND RELIABLE ROUTING PROTOCOL FOR WIRELESS SENSOR NETWORKS

by

Kamil Samara

The University of Wisconsin-Milwaukee, 2016

Under the Supervision of Professor Hossein Hosseini

The Internet of Things (IoT) is shaping the future of Computer Networks and Computing in general, and it is gaining ground very rapidly. The whole idea has originated from the pervasive presence of a variety of things or objects equipped with the internet connectivity. These devices are becoming cheap and ubiquitous, at the same time more powerful and smaller with a variety of onboard sensors. All these factors with the availability of …

Synthesis Of Subtype Selective Bz/Gabaa Receptor Ligands For The Treatment Of Anxiety, Epilepsy And Neuropathic Pain, As Well As Schizophrenia And Asthma, Michael M. Poe

Theses and Dissertations

The α2/α3 subtype selective Bz/GABAA receptor positive allosteric modulator HZ-166 (3) has been shown to be a nonsedating anxiolytic with anticonvulsant and antihyperalgesic activity. However, instability in vitro and in vivo has hindered its advancement into clinical trials. A series of ligands based off HZ-166 (3) were synthesized. Many of these ligands were designed to increase metabolic stability, while others were synthesized to study the effects that electronics and sterics have on the efficacy exerted when bound to the GABAA receptor. The α3 subtype selective methyl ester MP-III-024 (19) was shown to have increased resistance to metabolism in in vitro …

Modelling Of Dreissenid Mussel Impacts On Lake Michigan, Chunqi Shen

Theses and Dissertations

Invasive dreissenid mussel appear to have profoundly altered Great Lakes food webs and nutrient cycles during the past several decades. Recent declines of phytoplankton were supposed to be highly related with the increase of mussel population. These phytoplankton declines were further found to be coincident with declines in the abundance of planktivorous fish. In addition, the resurgence of Cladophora in Great lakes was estimated to be associated with the high density colonization of mussels. More light is available at lake bottom due to the mussels’ graze effect. The mussels further promote Cladophora growth by fertilizing it with nutrient-rich excrement. And …

Phase Sensitive Thermography Of Magnetostrictive Materials Under Periodic Excitations, Peng Yang

Theses and Dissertations

The use of giant magnetostrictive materials in actuator and sensor applications is still relatively new. Giant magnetostrictive materials, such as Terfenol-D, are unique in producing large deformation under a magnetic field. Applications of these materials in solid state actuators and transducers may require more knowledge on the interaction between geometry and material properties for a specific design. In order to gain more understanding of the magnetostriction mechanism, phase sensitive or lock-in thermography has been used to study Terfenol-D. Thermography is useful in that it allows for full field measurement of the surface of an object with a relatively simple setup. …

Electrical Measurements And Attenuated Total Reflection Infrared Spectroscopic Study Of Aromatic Isocyanides And Thiols On Gold, Rasha Khaled Abuflaha

Theses and Dissertations

In 1947, Bell Laboratories produced an amplifier design in which an electric field would enhance the flow of electrons near the surface of a layer of silicon, it was called the “point-contact transistor”, the world’s first semiconductor amplifier. In order to minimize the electronic circuit elements (device miniaturization), the ability to utilize single molecules that function as self-contained electronic devices (molecular electronics) has motivated researchers around the world. Molecular electronics investigates single molecules and collections of molecules assembled into electronic circuits. Currently, semiconductor devices are fabricated using a “top-down” approach that employs lithographic and etch techniques to pattern a substrate, …

The Function Of Renalase, Brett Allen Beaupre

Theses and Dissertations

Renalase was originally reported to be an enzyme secreted into the blood by the kidney to lower blood pressure and slow heart rate. Despite multiple reports claiming to confirm this activity in vivo there has been considerable discord in regards to the reaction catalyzed by renalase. The structural topology of renalase resembles that of known flavoprotein oxidases, monooxygenases and demethylases, but the conserved active site residues are unique to renalase. It has been reported that the catalytic function of renalase is to oxidize circulating catecholamines, however in vitro studies have failed to demonstrate a catalytic activity in the presence of …

A New Paradigm Of Maximizing The Wind And Solar Penetration– A Economical Assessment, Yuming Chen

Theses and Dissertations

Wind and solar energies are the most potential and widely-used renewable energies. But in most cases these energies cannot be maximized because of transmission line capacity and their remote location. Therefore, this thesis proposes a new paradigm which using battery transportation and logistics instead of transmission line, to maximize wind and solar energies. The main focus of this work is to investigate the economical feasibilities of this new paradigm.

In the first part, different models and application are presented. The purpose is finding an appropriate model which can make full use of existing grid resources such as transmission line and …

3d Sem Surface Reconstruction: An Optimized, Adaptive, And Intelligent Approach, Ahmad Pahlavan Tafti

Theses and Dissertations

Structural analysis of microscopic objects is a longstanding topic in several scientific disciplines, including biological, mechanical, and material sciences. The scanning electron microscope (SEM), as a promising imaging equipment has been around to determine the surface properties (e.g., compositions or geometries) of specimens by achieving increased magnification, contrast, and resolution greater than one nanometer. Whereas SEM micrographs still remain two-dimensional (2D), many research and educational questions truly require knowledge and information about their three-dimensional (3D) surface structures. Having 3D surfaces from SEM images would provide true anatomic shapes of micro samples which would allow for quantitative measurements and informative visualization …

Synthesis And Performance Analysis Of Polyurethane Foam Nanocomposite For Arsenic Removal From Drinking Water, Faten Bakri Hussein

Theses and Dissertations

Water contamination by various heavy metal pollutants such as, Lead, Arsenic, Cadmium, and Mercury, have severe toxic effects on living organisms and humans. High concentrations of arsenic in drinking water cause serious damage to the central and peripheral nervous systems, as well as, the dermal, cardiovascular, gastrointestinal, and respiratory systems. Arsenic contamination of ground water poses a substantial concern in many countries throughout the world, including the United States.

Considerable research work, aimed at finding and developing various separation and treatment techniques, has been conducted over the past few decades. The conventional treatment methods of arsenic involve coagulation with ferric …

A Conservative Type System Based On Fractional Permissions, Chao Sun

Theses and Dissertations

The system of fractional permissions is a useful tool for giving semantics to various

annotations for uniqueness, data groups, method effect, nullness, etc. However, due

to its complexity, the current implementation for fractional permissions has various

performance issues, and is not suitable for real world applications.

This thesis presents a conservative type system on top of the existing fractional

permission type system. The system is designed with high-level types, and is more

restrictive. The benefit is that it can run much faster. With this system, we propose a

multi-tiered approach for type checking: the conservative type system is first applied, …

The Selective Survival Of Escherichia Coli In Freshwater Beach Sand, Natalie Ann Rumball

Theses and Dissertations

The quantification of Escherichia coli or E. coli is the most common method used to detect recent fecal pollution in recreational water, as this species is known for its high abundance in fecal matter and assumed host-associated nature. However, it has been determined that some strains are capable of long-term survival and potential propagation in non-host environments, such as the beach sand. These long-term environmental survivors are host-independent and are not associated with the same health risks as those E. coli from recent fecal pollution. However, they have been shown to impact how water quality is perceived as they are …