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Synthesis And Characterization Of Catalysts For The Selective Transformation Of Biomass-Derived Materials, Isaac Tyrone Ghampson

Electronic Theses and Dissertations

The experimental work in this thesis focuses on generating catalysts for two intermediate processes related to the thermal conversion of lignocellulosic biomass: the synthesis and characterization of mesoporous silica supported cobalt catalysts for the Fischer-Tropsch reaction, and an exploration of the reactivity of bulk and supported molybdenum-based nitride catalysts for the hydrodeoxygenation (HDO) of guaiacol, a lignin model compound. The first section of the work details the synthesis of a series of silicasupported cobalt Fischer-Tropsch catalysts with pore diameters ranging from 2-23 nm. Detailed X-ray diffraction measurements were used to determine the composition and particle diameters of the metal fraction, …

Development Of A Scale Model Wind Turbine For Testing Of Offshore Floating Wind Turbine Systems, Heather Rae Martin

Electronic Theses and Dissertations

This thesis presents the development of a 1/50th scale 5 MW wind turbine intended for wind and wave basin model testing of commercially viable floating wind turbine structures. The design is based on a popular 5 MW wind turbine designed by the National Renewable Energy Laboratory (NREL) commonly utilized in numerical modeling efforts. The model wind turbine is to accompany generic floating model platforms for basin model testing. The ultimate goal of the model development testing program is to collect data for validating various floating wind turbine simulation codes such as those developed by NREL. This thesis will present an …

Adsorption And Diffusion Of Light Hydrocarbons In Ddr Zeolite, Adam Vidoni

Electronic Theses and Dissertations

This thesis reports the results of an experimental study aimed at characterizing the transport properties of DDR crystals (a pure silica zeolite analog) by the “zero length column” technique. This material is potentially useful as a size selective molecular sieve adsorbent for separation of CH₄ – CO₂ in the upgrading of low grade natural gas (or biogas) as well as for the separation of C₃H₆ - C₃H₈ for production of polypropylene. In both these applications pure silica zeolites (such as DDR) have important practical advantages over the traditional cationic zeolites since they …

Characterization Of Mesoporous Materials Via Fluorescent Spectroscopic Methods, Raymond Russell Kennard

Electronic Theses and Dissertations

There are three components that need to be understood to create new porous membranes for industrial applications. 1.) To understand appropriate synthesis conditions to create a successful membrane system. 2.) To understand how the microstructures generated in synthesis affect the transport properties of that system. 3) To be able to characterize the heterogeneity of the fabricated membrane’s transport and physical structure.

Presented within this manuscript are new characterization methods to increase the understanding in membrane technology. It will be demonstrated that the novel application of standard fluorescent methods and the development of new fluorescent methods techniques allows for the measurement …

U.S. Forest Service Northern Conifer Experimental Forests: Historical Review And Examples Of Silvicultural Research Applications, Kate Berven

Electronic Theses and Dissertations

This study investigates U.S. Forest Service silvicultural research in the northern mixed-conifer forest of the Northeast. Chapter 1 is an overview of three closed experimental forests and is a cautionary tale regarding lost research opportunities. The Paul Smith, Finch-Pryun, and Gale River Experimental Forests (EFs) were established in the early to mid 1900s. Changing societal needs and research priorities led to redirected staffing and funding; all three were disestablished. Initial investments were lost and outcomes of the experiments not fully realized. This chapter highlights the importance of retaining and properly storing records. The Penobscot EF is an exemplary illustration of …

Examining The Role Of Specific Virulence Mechanisms During Pseudomonas Aeruginosa Infection In A Zebrafish Model Of Cystic Fibrosis, Ryan T. Phennicie

Electronic Theses and Dissertations

Cystic fibrosis (CF) is the most common lethal hereditary disease. CF is caused by recessive mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene and is associated with multi-­-organ defects resulting from improper ion transport across epithelial membranes. Chronic lung infection by the environmentally ubiquitous opportunistic human pathogen Pseudomonas aeruginosa and the subsequent hyperinflammation that occurs as the host immune system combats the bacterium cause substantial morbidity and mortality in CF. Despite numerous studies that have sought to elucidate the role of CFTR in the innate immune response, the links between CFTR, innate immunity, and P. aeruginosa infection remain …

The Millimeter Legal Coordinated Cadastre, Carlton A. Brown

Electronic Theses and Dissertations

Land ownership is an important part of a nation’s wealth. Land value is determined by information about the land and about property rights that exist over the land. The Cadastre is the primary means of providing information about property rights, providing the private and public sector with: information identifying those people who have interests in parcels of land; information about those interests; and information about the parcels. The definitive cadastre would require anyone looking for information about a parcel of land to only go to the cadastre to find everything there is to know about the land such as: • …

Event Discovery And Classification In Space-Time Series: A Case Study For Storms, Avinash Rude

Electronic Theses and Dissertations

Recent advancement in sensor technology has enabled the deployment of wireless sensors for surveillance and monitoring of phenomenon in diverse domains such as environment and health. Data generated by these sensors are typically high-dimensional and therefore difficult to analyze and comprehend. Additionally, high level phenomenon that humans commonly recognize, such as storms, fire, traffic jams are often complex and multivariate which individual univariate sensors are incapable of detecting. This thesis describes the Event Oriented approach, which addresses these challenges by providing a way to reduce dimensionality of space-time series and a way to integrate multivariate data over space and/or time …

How Service-Learning Can Counter Cultural Narcissism, Gretchen Jordan

Electronic Theses and Dissertations

This thesis defines and describes cultural narcissism as a societal syndrome and details the causes and perpetrators of this cultural shift in the United States. More specifically, it explores the implications of cultural narcissism in our youth and the educational system. Next, it looks at the responsibility of public and private schools as civic education centers. This thesis proposes service-learning as a viable solution for the educator to combat cultural narcissism.

Exfoliated Graphite Nanoplatelet-Filled Impact Modified Polypropylene Nanocomposites, Alex Duguay

Electronic Theses and Dissertations

Exfoliated graphite nanoplatelets (xGnP)-filled polymer composites have demonstrated superior electrical, mechanical, physical and thermal properties and are becoming a major focus for both academic and industrial research and development (R&D) activities. The main objective of this study was to characterize the influence of xGnP particle diameter, filler loading and the addition of coupling agents on the mechanical, rheological and thermal properties of xGnP-filled impact modified polypropylene (IMPP) composites. IMPP is currently being used at the AEWC Advanced Structures and Composites Center in polymer impregnated (pre-preg) fiber reinforced polymer (FRP) tapes consisting of an IMPP matrix polymer and E-glass continuous fibers. …

Interannual Variability In American Lobster Settlement: Correlations With Sea Surface Temperature, Wind Stress And River Discharge, Mahima Jaini

Electronic Theses and Dissertations

Recruitment to benthic marine populations is fundamentally a biophysical problem. The American Lobster Settlement Index is an annual diver-based survey of the young-of-year American lobsters (Homarus americanus) found in inshore nurseries in New England, USA and Atlantic Canada at the end of the postlarval settlement season. The considerable interannual variability in the settlement index suggests that environmental factors play an important role in regulating planktonic larval supply and transport. In this study, I focused on the longest settlement time series from three oceanographically contrasting regions: Midcoast Maine, coastal Rhode Island and the lower Bay of Fundy. Sampling in these regions …

Photonic Non-Destructive Measurement Methods For Investigating The Evolution Of Polar Firn And Ice, Daniel James Breton

Electronic Theses and Dissertations

When snow falls on glaciers or ice sheets, it persists for many tens, hundreds and sometimes thousands of years before becoming ice. The granular material in between fresh snow and glacial ice is known as firn and is generally 50 to 100 m thick over polar ice sheets. The compaction mechanism of firn into ice (called densification) has important glaciological ramifications in determination of ice sheet stability and related sea level rise effects via remote sensing altimetry. Firn densification is also important for correctly interpreting ice core paleoclimate records, especially those analyzing gases trapped in air bubbles within the glacial …

Lower Limb Acceleration During The Block-Start Vs. Selected Power And Strength Exercises, Thomas A. Ordelt

Electronic Theses and Dissertations

The purpose of this study was to determine the effect of load changes on angular accelerations of the ankle, knee and hip joints. Accelerations were measured in the squat (S), power clean (PC) and power hang clean (PHC), and compared to the accelerations in the push-off phase of the sprint start (SS). Methods: Nine female Division I college track athletes performed block sprint-starts, single-leg squat jumps (1S0) with 0% of 1RM, squats (jump) with 0, 25, 40% of 1RM, and PC and PHC with 30, 50, 75, 100% of 1RM. The fastest trial of each exercise was analyzed for minimum …

Faculty And Administrators Working Together In A Community College: A Retrospective Case Study, Paul J. Charpentier

Electronic Theses and Dissertations

Community colleges are facing many large-scale problems, such as increased accountability, in a time of shrinking budgets and students who are often unprepared for college level work. The implications of these problems to institutions that are striving to maintain access to higher education for vulnerable populations are grave. These problems, and others, require creative solutions that involve numerous individuals and groups across the institution. The purpose of this retrospective case study was to learn how faculty and administrators experienced collaboration in the context of a community college. The study was carried out at Southern Maine Community College (SMCC) in South …

A Theoretical Model Of A Lateral-Field Excited Sensor Element Under Liquid Loading, Lester A. French

Electronic Theses and Dissertations

The lateral-field excited (LFE) acoustic wave sensor element has been shown to be more sensitive to mass, viscous, and electrical loading than the quartz crystal microbalance. Despite this, no equivalent circuit exists to model the LFE sensor element under simultaneous mechanical and electrical loading by a liquid. In this work an equivalent circuit model of the LFE sensor element loaded with a Newtonian liquid is developed. This equivalent circuit model is the first to model an LFE sensor under liquid loads with lumped elements that relate to the piezoelectric crystal and the material properties of the contacting liquid. The LFE …

Exfoliated Graphite Nanoplatelet-Filled Impact Modified Polypropylene Nanocomposites, Alex Duguay

Electronic Theses and Dissertations

Exfoliated graphite nanoplatelets (xGnP)-filled polymer composites have demonstrated superior electrical, mechanical, physical and thermal properties and are becoming a major focus for both academic and industrial research and development (R&D) activities. The main objective of this study was to characterize the influence of xGnP particle diameter, filler loading and the addition of coupling agents on the mechanical, rheological and thermal properties of xGnP-filled impact modified polypropylene (IMPP) composites. IMPP is currently being used at the AEWC Advanced Structures and Composites Center in polymer impregnated (pre-preg) fiber reinforced polymer (FRP) tapes consisting of an IMPP matrix polymer and E-glass continuous fibers. …

Late-Pleistocene Glacial And Climate Fluctuations In The Torres Del Paine Region (51ºs), Southern South America, Juan Luis Garcia

Electronic Theses and Dissertations

Variations in Earth‘s orbital parameters affect insolation and are thought to drive ice-age cycles (Milankovitch Theory). Northern and southern mid-latitudes show opposing insolation signals, because of the effect of precession. Despite this difference, paleoclimate records from both hemispheres display broadly synchronous glacialinterglacial climate changes tied to northern hemisphere insolation. This would imply that southern hemisphere glaciers advanced in the face of increasing local summer insolation during the last glacial maximum and thus raises questions about the orbital theory of ice ages. Well-dated paleoclimate records are important for testing hypotheses concerning the origin of ice ages, particularly in the southern hemisphere. …

Electronic Transport Properties Of Ruthenium And Ruthenium Dioxide Thin Films, Michael M. Steeves

Electronic Theses and Dissertations

Resistivities (ρ) and Hall coefficients (R_H) of polycrystalline Ru and RuO₂ thin films were measured from 293 to 600 K in vacuum, O₂, and CO. Differing nanostructures and textures were sputtered at normal, confocal, and glancing incidences to 20 - 300 nm thickness. For Ru in planar or nanorod morphologies, defects have negligible effect on R_H, which is similar to R_H in bulk metal. Models of effective thickness are derived for the nanorod morphology. For Ru and RuO₂ films, decreases in ρ on first heating are caused by defect annealing; subsequent …

Identifying And Addressing Specific Student Difficulties In Advanced Thermal Physics, Trevor I. Smith

Electronic Theses and Dissertations

As part of an ongoing multi-university research study on student understanding of concepts in thermal physics at the upper division, I identified several student difficulties with topics related to heat engines (especially the Carnot cycle), as well as difficulties related to the Boltzmann factor. In an effort to address these difficulties, I developed two guided-inquiry worksheet activities (a.k.a. tutorials) for use in advanced undergraduate thermal physics courses. Both tutorials seek to improve student understanding of the utility and physical background of a particular mathematical expression. One tutorial focuses on a derivation of Carnot's theorem regarding the limit on thermodynamic efficiency, …

Learning To Discuss Literature Online: Where Technology Design And Instruction Intersect, Kenneth H. Martin

Electronic Theses and Dissertations

While agreement exists that computer-mediated communication (CMC) should support rich discussion, research has not yet established how or if such discussion can be realized. The problem is that users often do not attend effectively to others’ entries. The main question guiding this case study was the following: How does an introduction to the design elements of Moodle Forum in a twelfth-grade English classroom influence participants’ threaded discussion? Drawing upon CMC research, this investigation documented the impact of a 15-week instructional intervention designed to increase users’ explicit reference to peers’ entries in Moodle Forum discussion. Participants included twenty students in two …

High Resolution Antarctic Glaciochemical Climate Proxy Records And Their Global Implications, Daniel Arthur Dixon

Electronic Theses and Dissertations

The first section of this study presents major ion, trace element, heavy metal, rare earth element and oxygen isotope data from a series of surface snow samples and shallow firn sections collected along four US ITASE traverses across extensive regions of East and West Antarctica. In each sample the dissolved major ion, total trace element, and d18O concentrations are measured. This provides a baseline from which changes in the chemistry of the atmosphere over Antarctica can be monitored under expected warming scenarios and continued intensification of industrial activities in the Southern Hemisphere. Satellite remote sensing measurements of microwave backscatter and …

Do Relationships With Helpful And Not-Helpful Teachers Make A Difference? Perspectives From Nine At-Risk Adolescents, Emanuel Pariser

Electronic Theses and Dissertations

Every year in the United States close to 25% of students fail to graduate with the classmates with whom they began high school. The economic, social and personal impact of not completing high school is staggering on the individual and society. The literature fails to adequately document relational factors in the classroom that can alter the academic trajectory of at-risk students. This dissertation explores how nine at-risk adolescents view the impact of relationships with helpful and not-helpful teachers on their academic success. My three research questions were: (a) what qualities do at-risk students attribute to helpful and not-helpful teachers; (b) …

Forest Succession And Amphibian Migrations: Implications For Landscape Connectivity, Viorel Dan Popescu

Electronic Theses and Dissertations

Conservation of forest-dependent amphibians is dependent on finding a balance between timber management and species’ habitat requirements. Accurate predictions of the response of amphibian communities to disturbance rely on a good understanding of the scales at which ecological processes affect distribution and abundance through space and time. I investigated the response of 14 species to four different forestry treatments (partial harvest, clearcut with coarse woody debris [CWD] removed, clearcut with CWD retained, and uncut control) over a six-year period, using 2.1-ha experimental treatments. Forest amphibians showed a strong negative response to complete canopy removal at a broad spatial scale, but …

Crenulation Cleavage Development And The Influence Of Rock Microstructure On Crustal Seismic Anisotropy, Felice Maria Johanna Naus-Thijssen

Electronic Theses and Dissertations

This thesis investigates the cause of mass transfer during crenulation cleavage formation and the role that elastically anisotropic minerals and fabric development play in promoting seismic anisotropy in the crust. Crenulation cleavage is the most common fabric in multiplydeformed, phyllosilicate-rich metamorphic rocks. During its formation the originally planar fabric gets crenulated, eventually leading to the differentiation of quartz- and feldspar-rich regions (QFdomains) in the crenulation hinges, and phyllosilicate-rich regions (P-domains) in the crenulation limbs. This differentiation is driven by the dissolution of quartz and feldspar in the P-domains, and the precipitation of those minerals in the QF-domains. Finite element models …

The Extended Kalman-Consensus Filter, Andrew Pellett

Electronic Theses and Dissertations

An algorithm called the extended Kalman-Consensus filter is developed as an extension of the Kalman-Consensus filter to the non-linear case. The extended Kalman- Consensus filter is a technique for estimating the state of a non-linear process disturbed by noise using multiple observations from a distributed set of sense nodes. All sense nodes attempt to estimate the same state by determining how their observations affect that state, and by communicating with neighbor nodes. The algorithm is designed to be more accurate through measurement diversity, scalable to a large number of nodes, and robust against loss of nodes during operation. Simulations are …