Digital Commons Network^™

Effect Of Bronsted And Lewis Acids On Biochemical Conversion Of Various Lignocellulosic Feedstocks Into Biofuels And Chemicals, Srinivas Reddy Kamireddy

Theses and Dissertations

A biochemical process was investigated in the conversion of lignocellulosic biomass into biofuels and value added chemicals. Kenaf, two species of sorghum (brown mid rib (BMR) & non brown mid rib (NBMR)), sunn hemp, sunflower hulls, and cornstover were used as feedstocks in this study.

Lignocellulosic biomass primarily consists of three different components, cellulose, hemicellulose and lignin. In order to separate different fractions, and acid pretreatment is generally employed. This was achieved by using a 300 ml internal volume batch reactor. The heating source used was steam. During acid pretreatment most of the hemicellulose is hydrolyzed into the liquid fraction. …

Automated Usability Testing Of Websites Using Link Structure, Christoffer Odegaard Korvald

Theses and Dissertations

Websites keeps getting more important in business and other aspects of society. Making the websites as usable as possible is crucial as difficult to use systems tend to frustrate users, which might lead to users leaving or lost revenue for a business. Usability testing is needed to identify and fix those issues. Manual tests in usability labs can be very time consuming and costly. An automated system could reduce time and cost of testing, but are often too focused on one aspect to give a clear view of what needs to be fixed. A system to improve this is needed. …

Depression, Negative Self-Disclosure, And The Response Of Others On Facebook, Daniel Barrett Landauer

Theses and Dissertations

Depression has a number of deleterious effects on the interpersonal functioning of adolescents and emerging adults. The interpersonal theory of depression posits that depression is developed and maintained by both the behaviors of the individual and the responses of others to the individual. Adolescents and emerging adults are spending a significant amount of time interacting on social networking sites, such as Facebook, yet few studies have looked at the interpersonal behavior of depressed youth in the context of the interpersonal theory of depression. This study examined the interpersonal behavior of 328 emerging adult college students on Facebook using questionnaires related …

Investigation Of The Seasonal Variations Of Aerosol Physicochemical Properties And Their Impact On Cloud Condensation Nuclei Number Concentration, Timothy Logan

Theses and Dissertations

Aerosols are among the most complex yet widely studied components of the atmosphere not only due to the seasonal variability of their physical and chemical properties but also their effects on climate change. The three main aerosol types that are known to affect the physics and chemistry of the atmosphere are: mineral dust, anthropogenic pollution, and biomass burning aerosols. In order to understand how these aerosols affect the atmosphere, this dissertation addresses the following three scientific questions through a combination of surface and satellite observations:

SQ1: What are the seasonal and regional variations of aerosol physico-chemical properties at four selected …

Part I: An Approach To The Synthesis Of Plakortethers A-E Part Ii: Rhodium-Catalyzed Intramolecular C-H Insertion On Diazosulfonates And Its Synthetic Applications, Duminda Shiromalee Liyanage

Theses and Dissertations

This research work consists of two independent studies. The first study is the development of a synthetic route to plakortethers A-E along with possible derivatives. The second study focuses on the synthetic applications of rhodium-catalyzed intramolecular C-H insertion on diazosulfonates.

Plakortethers (A-G) represent a set of marine natural products, which contain of a characteristic tetrasubstituted tetrahydrofuran fragment. This group of compounds was isolated from the Caribbean sponge Plakortis simplex. Their selective cytotoxic activity against the RAW 264-7 cell lines (murine macrophage) makes them promising candidates for biological studies and, along with their unusual structure, warrants the synthesis of these natural …

An Experimental Investigation Of The Aerodynamic Losses For An Incident Tolerant Low Pressure Turbine Blade Over Moderate To Low Reynolds Numbers At Engine Representative Mach Numbers, Jonathan Long

Theses and Dissertations

In the interest of reducing airport congestion in the near future, researchers at NASA Glenn Research Facility have envisioned a new civilian transport aircraft which takes off vertically and cruises horizontally at Mach 0.5 using tilt-rotor technology. The engine under development consists of a four stage low pressure (LP) turbine. Many challenges are presented as the engine transitions from 100% shaft speed at takeoff to 54% shaft speed at cruise. The blading in this engine must be designed to optimize fuel efficiency, especially at cruise. The flow conditions in the LP turbine will change significantly from a Reynolds number of …

An Investigation On Relationship Between Epistemological Beliefs And Instructional Practice Of Preservice And Inservice Teachers, Jacob Manu

Theses and Dissertations

This quantitative research sought to investigate the relationship between epistemological beliefs and instructional practice of preservice and inservice teachers. Despite the vigorous emphasis and investment on the need for teachers to adopt teaching and learning practices that are more authentic, learner-centered, project-based, meaningful, and context-based, there is a growing trend where inservice teachers are trained in constructivist learning environment but end up adopting traditional learning pedagogies. Thus, teachers are constantly struggling to incorporate the tenets of constructivism into the teaching and learning process. With the use of the discipline-focused epistemological beliefs questionnaire and instructional practice scale, preservice and inservice teachers …

Advanced Reactors And Novel Reactions For The Conversion Of Triglyceride Based Oils Into High Quality Renewable Transportation Fuels, Michael James Linnen

Theses and Dissertations

Sustainable energy continues to grow more important to all societies, leading to the research and development of a variety of alternative and renewable energy technologies. Of these, renewable liquid transportation fuels may be the most visible to consumers, and this visibility is further magnified by the long-term trend of increasingly expensive petroleum fuels that the public consumes. While first-generation biofuels such as biodiesel and fuel ethanol have been integrated into the existing fuel infrastructures of several countries, the chemical differences between them and their petroleum counterparts reduce their effectiveness. This gives rise to the development and commercialization of second generation …

Metal Enhanced Fluorescence With Gold Nanoparticles, Shaina Larissa Strating Mattingly

Theses and Dissertations

A novel hybrid nanocomposite of Au nanoparticle-modified silicon nanowire was developed for surface enhanced fluorescence applications. The designed nanocomposite contained a silicon nanowire, gold nanoparticles and a silica layer doped with dye molecules. The hybrid nanomaterial was characterized using scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), fluorescence measurements, Fourier transform infrared (FT-IR) spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). The results showed that the gold nanoparticles were uniformly adhered on the silicon nanowires and covered by a thin silica layer. The nanostructure exhibited strong capacity for surface enhanced fluorescence. Different enhancement factors were obtained by changing synthetic conditions.

The …

A "Keeping Place For Souls": Photo, Body, And Narrative Impulse In Cormac Mccarthy's Suttree, Melissa Anne Mondry

Theses and Dissertations

This paper examines how the treatment of photographs in Cormac McCarthy's novel Suttree sheds light on its main character's narrative project, his motivation for writing and his approach to his subjects. It extends the work of critics who have identified the character of Suttree as a burgeoning writer in order to examine what this narrative subplot might indicate about the purpose of narrative in McCarthy's world. It also responds to previous readings of the novel's photo album scene, which have focused on photographs as reminders of death. I argue that Suttree's adverse reaction to photographs is more complicated than fear …

Relational Aggression Among Caucasian And Northern Plains American Indian School Children, Stephanie Parisien

Theses and Dissertations

Relational aggression is a form of aggression that has received increasing attention within the psychological literature. Among the American Indian population, however, research on relational aggression is currently non-existent. To date, research is continuing to grow with regard to the base rates of relational aggression. The current study has examined both peer-nominated and self-report relational aggression among Caucasian and Northern Plains American Indian school children in order to explore cultural, gender, grade level, and age differences. Other forms of aggression and social status were also explored in order to understand how these constructs may play a role in peer relations. …

Potential Juror Credibility Evaluations Of Gay And Lesbian Witnesses, Lisa Mae Olson

Theses and Dissertations

This study looked at whether the sexual orientation of a witness has an effect on a potential juror's determination of the witness's credibility, and examined traits such as respondent gender and college major, that may predict high levels of sexual prejudice. The sample consisted of 379 undergraduate students at a medium sized, upper Midwestern university. Results did not reveal an overall link between witness credibility ratings and sexual orientation, with the gay male witness receiving the highest credibility rankings followed by the heterosexual male witness, heterosexual female witness, and lastly, the lesbian female witness. It does not appear that the …

Some Versions Of Timon's Epitaph: Performance, Text, And Gift In Shakespeare And Middleton's Timon Of Athens, Silas Frederick Pera

Theses and Dissertations

This paper examines how notions of textuality influence the production of William Shakespeare and Thomas Middleton's Timon of Athens in both scholarly, print editions and in theatrical performances of the play. It focuses specifically on the scenes involving Timon's epitaph, which have proven difficult to handle both editorially and theatrically, and seeks to show how changing views of the nature of textuality has significantly altered the way that different readers and audiences encounter this play. These issues regarding the idea of textuality begin with the play itself, which enacts its own ideas about the power of texts to intervene in …

Emergence Of Algal Blooms: The Effects Of Short-Term Variability In Water Quality On Phytoplankton Abundance, Diversity, And Community Composition In A Tidal Estuary, Todd A. Egerton, Ryan E. Morse, Harold G. Marshall, Margaret R. Mulholland

OES Faculty Publications

Algal blooms are dynamic phenomena, often attributed to environmental parameters that vary on short timescales (e.g., hours to days). Phytoplankton monitoring programs are largely designed to examine long-term trends and interannual variability. In order to better understand and evaluate the relationships between water quality variables and the genesis of algal blooms, daily samples were collected over a 34 day period in the eutrophic Lafayette River, a tidal tributary within Chesapeake Bay's estuarine complex, during spring 2006. During this period two distinct algal blooms occurred; the first was a cryptomonad bloom and this was followed by a bloom of the mixotrophic …

A Video Game Cycling Intervention Assessing Exercise Enjoyment, Rpe, Heart Rate, And Total Work Output In College Students, Shawn Ryan Reich

Theses and Dissertations

Background: Physical inactivity can lead to numerous health issues. More recently, advances in technology have catered to this area of concern. Activity-promoting video games or exergames, have recently been providing consumers with an innovative and alternative experience to exercise. Traditional exercise modalities such as the cycle ergometer (CE) have utilized video game (VG) play to help increase exercise enjoyment and overall health benefits. However, few studies have examined CE and VG play in this regard.

Purpose: The purpose of this study was to investigate if cycling with a non-interactive CE while playing a VG is a viable option to increasing …

Novel Sustainable Structural Materials By Using Benign Waste Materials, M Faisal Riyad

Theses and Dissertations

We propose a Green Cement Paradigm (GCPa) for fabricating environmentally friendly cementitious materials. By using GCPa, we report for the first time, the usage of Class C Fly Ash as a sole source of cementitous phase without any activation by alkali. During this study, Class C Fly Ash, and its composites with sand were fabricated at different compaction stresses by maintaining a low w/c (w-water, c-cement) ratio of 0.17-0.24 in the compacts. The porosity and the number of days for curing played a significant role in the evolution of compressive strength. The experimental results indicate that the curing for 28 …

Investigation Of Marine Stratocumulus Under Coupled And Decoupled Conditions Over The Arm Azores Site, Adam Christopher Schwantes

Theses and Dissertations

Stratocumuli are a type of low clouds composed of individual convective elements that together form a continuous layer of clouds. Stratocumuli cover large regions of the Earth's surface, which make them important components in the Earth's radiation budget. Stratocumuli strongly reflect solar shortwave radiation, while weakly affecting outgoing longwave radiation. This leads to a strong radiative cooling effect that affects the Earth's radiation budget. Therefore it is important to investigate the mechanisms that affect the longevity of stratocumuli, so that their impact on the Earth's radiation budget can be fully understood. One mechanism that is currently being studied as influencing …

A Collapsar Model For Bright Linear Type Ii Supernovae And Numerical Simulations Of Multiple, Interacting Supernova Remnants, Dean D. Smith

Theses and Dissertations

This dissertation includes two projects. Part one applies the collapsar model to Bright Linear Type II supernovae. The collapsar model is commonly used to explain gamma-ray bursts. In this model, a stellar core collapses to a black hole surrounded by an accretion disk. In addition to the supernova caused by the core collapse, the black hole powers a high energy jet. Shocks within the jet create the gamma ray burst while the jet's later interaction with circumstellar material creates an afterglow. In a Type II supernova, the hydrogen envelope of the star results in a lower energy jet that does …

Bayesian Modeling For Dealing With Uncertainty In Cognitive Radios, Hector Ivan Reyes Moncayo

Theses and Dissertations

Wireless communication systems can be affected by several factors, including propagation losses, co-channel interference, and multipath fading. Uncertainty affects all of these factors making it even more difficult to model these systems. This dissertation proposes the use of probabilistic graphical models (PGM), such as Bayesian Networks and Influence Diagrams, as the core for reasoning and decision making in adaptive radios operating under uncertainty. PGM constitute a tool to understand and model complex relations among random variables. This dissertation explains how to build effective communication models that perform its functions under uncertainty. In addition, this work also presents a spectrum sensing …

Identifying Landscape-Level Trends In Prairie Songbirds With Fragmented Habitats, Jessica Shahan

Theses and Dissertations

Grassland songbirds are experiencing significant population declines due to habitat loss and degradation. This study investigated the relationship between landscape-level patterns and prairie-level patterns in presence/absence, richness, and diversity for seven individual species, the total grassland songbird community, and three community subgroups. Overall, grassland songbirds did respond to landscape-level variables, although the strength of the relationship and the variables involved differed by species and functional group.

Educational Experiences Of Rural Minnesota High-Ability Mathematics Learners, Jodi Lynn Sandmeyer

Theses and Dissertations

Meeting the educational needs of rural Minnesota high school high-ability learners in mathematics can be challenging for educators. This qualitative study involved interviewing high school graduates who scored between 30 and 36 on the mathematics subtest of the ACT and high school mathematics teachers who observed high-ability mathematics students. The graduates were from four different one-section or two-section schools from three counties in rural Minnesota. The purpose of this study was to use phenomenological qualitative research methods to identify educational experiences of high-ability mathematics learners from rural one-section and two-section high schools. There were two research questions guiding this study. …

Academic Achievement And Perceptions Of Nature Appreciation, Environmental Awareness, And Well-Being Of Participants In Sully's Hill Nature Education Program, Jared Duane Schlenker

Theses and Dissertations

Experiential and hands-on learning are important for any effective educational environment, and when combined with natural elements that can stimulate students' senses to enhance their learning, these educational methods may have a profound effect (Louv, 2008). The Sully's Hill Nature Education Program (SHNEP) allows fifth-grade students at Central Middle School in Devils Lake, North Dakota, to learn in an outdoor setting.

The purpose of this study was to determine if a relationship exists between Devils Lake fifth graders and sixth graders who participate(d) in the Sully's Hill Nature Education Program (SHNEP), and those students who have not participated in the …

Human Performance Profiles For Planetary Analog Extra-Vehicular Activities: 120 Day And 30 Day Analog Missions, Tiffany M. Swarmer

Theses and Dissertations

Understanding performance factors for future planetary missions is critical for ensuring safe and successful planetary extra-vehicular activities (EVAs). The goal of this study was to gain operational knowledge of analog EVAs and develop biometric profiles for specific EVA types. Data was collected for a 120 and 30 day analog planetary exploration simulation focusing on EVA type, pre and post EVA conditions, and performance ratings. From this five main types of EVAs were performed: maintenance, science, survey/exploratory, public relations, and emergency. Each EVA type has unique characteristics and performance ratings showing specific factors in chronological components, environmental conditions, and EVA systems …

Gravin Regulates Crosstalk Between Calcium And Pka Dependent Signaling Pathways In Cultured Cells, Micah Schott

Theses and Dissertations

A-Kinase Anchoring Proteins (AKAPs) comprise a family of roughly 70 scaffolds that anchor PKA and other enzymes to a variety of subcellular compartments. Although characterized as "anchoring proteins", some AKAPs are not spatially and temporally static but can undergo dynamic subcellular trafficking, thus repositioning anchored enzyme complexes within the cell. Gravin (also called SSeCKS or AKAP12) anchors PKA and other enzymes to the plasma membrane but redistributes to the cytosol upon intracellular calcium ([Ca2+]i) elevation. However, the impact of gravin redistribution on PKA-dependent signaling pathways is poorly understood. We hypothesize that through Ca2+-mediated redistribution, gravin facilitates cross-talk between Ca2+-dependent and …

Improving Satellite Quantitative Precipitation Estimates By Incorporating Deep Convective Cloud Optical Depth, Ronald Stenz

Theses and Dissertations

As Deep Convective Systems (DCSs) are responsible for most severe weather events, increased understanding of these systems along with more accurate satellite precipitation estimates will improve NWS (National Weather Service) warnings and monitoring of hazardous weather conditions. A DCS can be classified into convective core (CC) regions (heavy rain), stratiform (SR) regions (moderate-light rain), and anvil (AC) regions (no rain). These regions share similar infrared (IR) brightness temperatures (BT), which can create large errors for many existing rain detection algorithms. This study assesses the performance of the National Mosaic and Multi-sensor Quantitative Precipitation Estimation System (NMQ) Q2, and a simplified …

A Study Of Parents' Retrospective Opinions On Kindergarten Enrollment, Christopher D. Swenson

Theses and Dissertations

Should children born during the summer months be enrolled in kindergarten onetime or should they be delayed a year? The purpose of this comparative case study was to formulate recommendations for parents and schools based on parent perspectives who made the enrollment choice, but also have had four to five years to evaluate their decision.

The research identifies points of consideration for parents and schools regarding kindergarten enrollment decisions for children born shortly before the enrollment cutoff date.

The researcher gathered data from parents who previously made this decision and had the option to enroll their child on-time or delay …

Phytoplankton And Nutrient Dynamics In A Tidally Dominated Eutrophic Estuary: Daily Variability And Controls On Bloom Formation, Ryan E. Morse, Margaret R. Mulholland, Todd A. Egerton, Harold G. Marshall

OES Faculty Publications

To better understand nutrient dynamics and factors that promote the initiation of algal blooms, the Lafayette River, a tidal subestuary of Chesapeake Bay that experiences seasonal algal blooms, was sampled daily for a period of 54 d in the fall of 2005. Three phytoplankton blooms (chl a concentrations exceeding twice the average of monthly measurements from 2000 to 2009) occurred during this period: a mixed bloom of Akashiwo sanguinea and Gymnodinium sp., a monospecific Skeletonema costatum bloom, and a monospecific Gymnodinium sp. bloom. Over the sampling period, nutrient concentrations increased following precipitation events and were elevated between bloom periods but …

The Effect Of Non-Weight And Shape-Related Appearance Dissatisfaction On Eating Disordered Behaviors, Terra Towne

Theses and Dissertations

Studies have found that greater dissatisfaction with non-weight-related body parts is associated with drive for thinness and body dissatisfaction, suggesting that eating disorder behaviors may be compensatory mechanisms for less malleable aspects of appearance. The aim of the present study was to explore the relationship between non-weight and shape-related appearance dissatisfaction (NWSAD), perceived malleability, and eating disorder and appearance-related behaviors. Participants were students enrolled in undergraduate psychology courses at a mid-size midwestern university. All participants completed the Eating Disorders Examination Questionnaire, Drive for Muscularity Scale, Body Shape Questionnaire, visual analogue scales assessing NWSAD, appearance-related behaviors checklist, and a measure assessing …

Retrievals Of The Deep Convective System Ice Cloud Microphysical Properties Using The Arm Radar And Aircraft In-Situ Measurements, Jingjing Tian

Theses and Dissertations

This study presents an algorithm for retrieving the Deep Convective Systems (DCSs) ice cloud microphysical properties using the DOE Atmospheric Radiation Measurement (ARM) Ka-band Zenith Radar (KAZR) reflectivity during the Midlatitude Continental Convective Clouds Experiment (MC3E) at the ARM Southern Great Plain (SGP) site ( 36° 36' 18.0" N, 97° 29' 6.0" W) from April-June 2011. It is a challenge to retrieve DCS ice cloud microphysical properties due to the attenuation of cloud radar reflectivity, unknown particle size distributions (PSDs), and the bulk habit of the ice particles within the sample volume. To address the most pronounced of these radar …

Preparation And Analysis Of Evaporatively Bonded Superalloys For Use In Hydrogen Burning Gas Turbines, Serges Eric Tatsinkou Nguelo

Theses and Dissertations

Superalloys for use in hydrogen-burning gas turbines must demonstrate long-term durability in environments that may be more corrosive than typical turbines due to the presence of impurities in the combusted syngas. This long-term durability implies high oxidation and spallation resistance to different types of corrosion attacks as well as a high strength to be able to withstand the residual stresses induced by the temperature gradients. The performance of these superalloys in these environments can only be realistically assessed if their design involves a good understanding of the types of microcontaminants present in the syngas as well as resulting stresses induced …