Physical Sciences and Mathematics Commons^™

An Autothermal, Representative Scale Test Of Compost Heat Potential Using Geostatistical Analysis, William J. Mccune-Sanders

Graduate College Dissertations and Theses

Composting has been practiced for thousands of years as a way of stabilizing and recycling organic matter into useful soil amendments. Thermophilic compost releases significant amounts of heat at temperatures (~140 °F) that are useful for environmental heating or process water. This heat has been taken advantage of in various ways throughout history, but development of a widely adopted technology remains elusive.

The biggest barrier to adoption of compost heat recovery (CHR) systems is projecting accurate, attractive economic returns. The cost of transfer equipment is significant, and with variability in composting substrates and methods, it is difficult to predict the …

Applying Bayesian Belief Network To Understand Public Perception On Green Stormwater Infrastructures In Vermont, Qing Ren

Graduate College Dissertations and Theses

Decisions of adopting best management practices made on residential properties play an important role in reduction of nutrient loading from non-point sources into Lake Champlain and other waterbodies in Vermont. In this study, we use Bayesian belief network (BBN) to analyze a 2015 survey dataset about adoption of six types of green infrastructures (GSIs) in Vermont’s residential areas. Learning BBNs from physical probabilities of the variables provides a visually explicit approach to reveal the message delivered by the dataset. Using both unsupervised and supervised machine learning algorithms, we are able to generate networks that connect the variables of interest and …

Water Quality Performance And Greenhouse Gas Flux Dynamics From Compost-Amended Bioretention Systems & Potential Trade-Offs Between Phytoremediation And Water Quality Stemming From Compost Amendments, Paliza Shrestha

Graduate College Dissertations and Theses

Stormwater runoff from existing impervious surfaces needs to be managed to protect downstream waterbodies from hydrologic and water quality impacts associated with development. As urban expansion continues at a rapid pace, increasing impervious cover, and climate change yields more frequent extreme precipitation events, increasing the need for improved stormwater management. Although green infrastructure such as bioretention has been implemented in urban areas for stormwater quality improvements and volume reductions, these systems are seldom monitored to validate their performance. Herein, we evaluate flow attenuation, stormwater quality performance, and nutrient cycling from eight roadside bioretention cells in their third and fourth years …

Exploration Of Zirconium-Catalyzed Intermolecular Hydrophosphination With Primary Phosphines: Photocatalytic Single And Double Hydrophosphination, Christine Anne Bange

Graduate College Dissertations and Theses

Catalytic hydrophosphination has enormous potential in the selective preparation of value-added organophosphines, despite the challenge of the reaction. This dissertation aims to address the hurdles in catalytic hydrophosphination with respect to substrate scope, selectivity, and reaction conditions using [қ5 –N,N,N,N,C– (Me3SiNCH2CH2)2NCH2CH2NSiMe2CH2]Zr (1).

Compound 1 readily engages with a suite of primary phosphines. These are challenging substrates for this reaction, but 1 readily provides high conversions with these substrates. Increasingly large primary phosphines, including chiral phosphines, undergo catalysis with 1. Furthermore, a variety of underreported unsaturated substrates can be functionalized in catalytic hydrophosphination with 1. Alkynes are underreported substrates, but 1 …

Land Use, Power, And Knowledge At The Northern Resource Frontier: Mining, Public Engagement, And Contentious Land Imaginaries In Bristol Bay And The Yukon-Kuskokwim Delta, Jonathan Tollefson

Graduate College Dissertations and Theses

The Donlin and Pebbles mines are two of the eight industrial-scale hard rock mines currently under the review of Alaska’s Large Mine Permitting program. Both projects promise to deliver profit and employment to their respective regions: Pebble to Bristol Bay in the southwest, and Donlin to the Yukon-Kuskokwim Delta, just north of Pebble. Both projects would also produce exceptional quantities of waste and will require almost-unprecedented infrastructure development, potentially threatening the lives and subsistence livelihoods of the Alaska Native peoples in their respective regions. The Pebble project inspired international protest and led to the emergence of a powerful resistance coalition …

Fluvial Processes In Motion: Measuring Bank Erosion And Suspended Sediment Flux Using Advanced Geomatic Methods And Machine Learning, Scott Douglas Hamshaw

Graduate College Dissertations and Theses

Excessive erosion and fine sediment delivery to river corridors and receiving waters degrade aquatic habitat, add to nutrient loading, and impact infrastructure. Understanding the sources and movement of sediment within watersheds is critical for assessing ecosystem health and developing management plans to protect natural and human systems. As our changing climate continues to cause shifts in hydrological regimes (e.g., increased precipitation and streamflow in the northeast U.S.), the development of tools to better understand sediment dynamics takes on even greater importance. In this research, advanced geomatics and machine learning are applied to improve the (1) monitoring of streambank erosion, (2) …

Geochronologic Constraints On The Timing Of Metamorphism And Exhumation Of The Tillotson Peak Complex In Northern Vermont, Cheyne Aiken

Graduate College Dissertations and Theses

The Tillotson Peak Complex (TPC) in northern Vermont records high-pressure (HP) subduction zone metamorphism that occurred during the Ordovician Taconic Orogeny, and subsequent retrograde metamorphism and deformation that occurred during the Silurian Salinic Orogeny. Previous studies have documented a polymetamorphic history, with peak metamorphic pressures possibly up to 2.5 GPa and temperatures of 550°C. Prior to this research, constraints on the timing of metamorphism in the TPC were limited to a single Middle Ordovician 40Ar/39Ar total fusion age for glaucophane. This study integrates 40Ar/39Ar step heating analyses of multiple mineral phases and U-Pb dating of titanite with field and microstructural …

Unprecedented Reactivity And Applications Of 1-Aza-2-Azoniaallene Salts, Ramya Srinivasan

Graduate College Dissertations and Theses

1-Aza-2-azoniaallene salts, derived by oxidation of substituted hydrazones, are highly reactive cationic heteroallenes. These species participate in several mechanistically distinct reactions including: (1) intramolecular [3+2] cycloadditions, (2) polar [4 +2] cycloadditions, (3) stereospecific C-H aminations, (4) electrophilic aromatic substitutions, and (5) chloroamination reactions. We have shown that this versatile reactivity is governed by the length of the tether and nature of the π-system.

A novel intramolecular electrophilic aromatic substitution reaction is observed when the tether length separating the 1-aza-2-azoniaallene salt and a pendant aryl ring is three methylene units to generate alkylaryl azo products. Variations in the electronics and sterics …

Quantum Many - Body Interaction Effects In Two - Dimensional Materials, Sanghita Sengupta

Graduate College Dissertations and Theses

In this talk, I will discuss three problems related to the novel physics of two-dimensional quantum materials such as graphene, group-VI dichalcogenides family (TMDCs viz. MoS2 , WS2, MoSe2 , etc) and Silicene-Germanene class of materials.

The first problem poses a simple question - how do the quantum excitations in a graphene membrane affect adsorption? Using the tools of diagrammatic perturbation theory, I will derive the scattering rates of a neutral atom on a graphene membrane. I will show how this seemingly naive model can serve as a non-relativistic condensed matter analogue of the infamous infrared problem in Quantum Electrodynamics. …

Spectroscopic Insight Into Oxidative Heme Cleavage By The Non-Canonical Heme Oxygenase Isdg From Staphylococcus Aureus, Matthew A. Conger

Graduate College Dissertations and Theses

IsdG and IsdI are non-canonical heme oxygenases (HO) from Staphylococcus aureus that catalyze the oxidative cleavage of heme to give novel organic products (staphylobilins) and iron as a nutrient for the pathogen. Comparison of the reported equilibrium dissociation constant (Kd) values for heme from IsdG and IsdI compared to the reported concentration of the labile heme pool called into question whether these enzymes are competent HOs in vivo. We took advantage of a second-sphere Trp whose fluorescence is quenched upon heme binding, which led to Kd values 2-3 orders of magnitude smaller than reported in the literature. Importantly, these Kd …

Soil Aggregates: The Mechanistic Link To Increased Dissolved Organic Carbon In Surface Waters?, Malayika Cincotta

Graduate College Dissertations and Theses

Dissolved organic carbon (DOC) plays an important role in the global carbon (C) cycle because increases in aqueous C potentially contribute to rising atmospheric CO2 levels. Over the past few decades, headwater streams of the northern hemisphere have shown increased amounts of DOC coinciding with decreased acid deposition. Although the issue is widely discussed in the literature, a mechanistic link between precipitation composition and stream water DOC has not yet been proposed.

In this study, the breakup of soil aggregates is hypothesized as the mechanistic link between reduced acid deposition and DOC increases in surface waters. Specific hypotheses state that …

Microscale Controls On Lead Speciation In Soils: A Framework For Sustainable Remediation, Grant Reeder

Graduate College Dissertations and Theses

The potential of a soil to immobilize heavy metal ions is dependent on the presence of adsorption sites, and the stability of metal species over the range of geochemical conditions present in the soil over time. Lead (Pb) is a cumulative toxin that is enriched in much of the urban pedosphere due to historical use of Pb-based paint and Pb-amended gasoline. Because in-situ remediation of Pb is possible if the bioavailable fraction can be rendered inert, understanding Pb-sorbent interactions is necessary to accurately and efficiently alter Pb speciation in soils. The objectives of this study are to 1) determine efficient …

Some Results On A Class Of Functional Optimization Problems, David Rushing Dewhurst

Graduate College Dissertations and Theses

We first describe a general class of optimization problems that describe many natu- ral, economic, and statistical phenomena. After noting the existence of a conserved quantity in a transformed coordinate system, we outline several instances of these problems in statistical physics, facility allocation, and machine learning. A dynamic description and statement of a partial inverse problem follow. When attempting to optimize the state of a system governed by the generalized equipartitioning princi- ple, it is vital to understand the nature of the governing probability distribution. We show that optimiziation for the incorrect probability distribution can have catas- trophic results, e.g., …

Novelty Detection Of Machinery Using A Non-Parametric Machine Learning Approach, Enrique Angola

Graduate College Dissertations and Theses

A novelty detection algorithm inspired by human audio pattern recognition is conceptualized and experimentally tested. This anomaly detection technique can be used to monitor the health of a machine or could also be coupled with a current state of the art system to enhance its fault detection capabilities. Time-domain data obtained from a microphone is processed by applying a short-time FFT, which returns time-frequency patterns. Such patterns are fed to a machine learning algorithm, which is designed to detect novel signals and identify windows in the frequency domain where such novelties occur. The algorithm presented in this paper uses one-dimensional …

Fragmentation, Rearrangement, And C-H Insertion: Reactions Of Vinyl Cations Derived From Diazo Carbonyls, Sarah Elizabeth Cleary

Graduate College Dissertations and Theses

Many commercialized medicinal compounds are analogs of chemicals isolated from sources found in nature (also called natural products). However, the natural sources of these chemicals, such as plants, fungi, or insects, only offer small quantities of these bioactive agents. Thus, it is typically desirable to find ways to synthesize these products and their analogs in large quantities using cost-effective methods that also minimize the impact on the environment. It is also important to develop strategies that expedite the process of modifying the natural products, which allows medicinal chemists to determine which functional groups are enhancing or deleterious to the bioactivity. …

Ecological Stormwater Management: Analysis Of Design Components To Improve Understanding And Performance Of Stormwater Retention Ponds, Rebecca Tharp

Graduate College Dissertations and Theses

Stormwater runoff from developed land is a source of pollution and excessive flow to waterways. The most commonly employed practices for flow and volume control are stormwater ponds and basins (also referred to as detention and retention ponds). These structures can be effective at controlling peak discharge to water bodies by managing flow timing but are often ineffective at removing nutrients, particularly in dissolved forms. Pond morphology coupled with place-specific characteristics (like soil type and drainage area characteristics) may influence plant community composition in these water bodies. The interaction of physical, chemical, and biological elements in stormwater ponds may affect …

Application Of Geophysical And Geochronological Methods To Sedimentologic And Stratigraphic Problems In The Lower Cambrian Monkton Formation: Northwestern Vermont, Henry C. Maguire

Graduate College Dissertations and Theses

The Monkton Formation of the western shelf stratigraphic sequence in Vermont (VT) is identified as a Lower Cambrian regressive sandstone unit containing parasequences recording tidal flat progradation. Previous workers identified cycles believed to represent parasequences in a portion of a 1034' deep geothermal well drilled at Champlain College in Burlington, Vermont. For this study, both outcrop and well geophysical surveys were completed to better identify gamma emission curves and relative values for parasequences and select lithologies that are indicators of bathymetry and sea level. After using physical stratigraphic techniques to assemble a composite stratigraphic section for the Monkton Formation, analysis …

Geochronological Constraints On The Timing Of Deformation: An Examination Of The Prospect Rock Fault Footwall In North-Central Vermont, Evan Tam

Graduate College Dissertations and Theses

The Prospect Rock Fault (PRF) is key to our understanding of the regional tectonic evolution of Vermont during the Taconic, Salinic, and Acadian Orogenies, and may have played an important role in the exhumation of blueschist and eclogite-facies rocks in the Tillotson Peak Complex (TPC) during the Taconic Orogeny. The TPC is in the footwall of the PRF in the eastern limb of the Green Mountain Anticlinorium. In the TPC, the dominant foliation is S2 and E-W trending F2 folds parallel L2 stretching lineations, which trend orthogonal to regional N-S trending folds associated with the Taconic Orogeny. The PRF itself …

Combining Observations Of Soils And Streams To Investigate Trends Caused By Reduced Acid Depositon In The Sleepers River Watershed, Jesse Armfield

Graduate College Dissertations and Theses

Acid deposition forms when emission-derived sulfur dioxide and nitrogen oxides interact with precipitation and was particularly severe in the northeastern US. Effects of acid deposition include declining soil quality due to low pH and base cation leaching, which subsequently altered the composition of soil solution, ground water (GW) and eventually stream water. Because of the high buffering capacity of carbonates, watersheds underlain by carbonate rich rocks have received limited attention in acid deposition studies, however, carbonate weathering by strong anthropogenic acids can increase atmospheric CO2 levels.

Emission reductions due to the Clean Air Act and Amendments has led to a …

Improving Scalability Of Evolutionary Robotics With Reformulation, Anton Bernatskiy

Graduate College Dissertations and Theses

Creating systems that can operate autonomously in complex environments is a challenge for contemporary engineering techniques. Automatic design methods offer a promising alternative, but so far they have not been able to produce agents that outperform manual designs. One such method is evolutionary robotics. It has been shown to be a robust and versatile tool for designing robots to perform simple tasks, but more challenging tasks at present remain out of reach of the method.

In this thesis I discuss and attack some problems underlying the scalability issues associated with the method. I present a new technique for evolving modular …

Smart Classifiers And Bayesian Inference For Evaluating River Sensitivity To Natural And Human Disturbances: A Data Science Approach, Kristen Underwood

Graduate College Dissertations and Theses

Excessive rates of channel adjustment and riverine sediment export represent societal challenges; impacts include: degraded water quality and ecological integrity, erosion hazards to infrastructure, and compromised public safety. The nonlinear nature of sediment erosion and deposition within a watershed and the variable patterns in riverine sediment export over a defined timeframe of interest are governed by many interrelated factors, including geology, climate and hydrology, vegetation, and land use. Human disturbances to the landscape and river networks have further altered these patterns of water and sediment routing.

An enhanced understanding of river sediment sources and dynamics is important for stakeholders, and …

Cityscape Connections: National Park Service Relevance And Resilience In Urban Areas, Elizabeth Eleanor Perry

Graduate College Dissertations and Theses

The National Park Service (NPS) strives to embody U.S. democratic ideals, conserving our collective stories and scenery for their intrinsic value and the enjoyment of current and future generations. However, although these places are conserved for all, they are not enjoyed by all. As with other conservation agencies, the NPS finds itself increasingly concerned with building relevance with diverse potential stewards. In cities, where 80% of the U.S. population and 40% of the NPS portfolio is based, there is a prime opportunity to build relevance with large, diverse, and proximate audiences. Recognizing this opportunity, the NPS initiated its Urban Agenda …

Conservation Of Ecosystem Services And Biodiversity In Vermont, Usa, Keri B. Watson

Graduate College Dissertations and Theses

Supporting a growing human population while avoiding biodiversity loss is a central challenge towards a sustainable future. Ecosystem services are benefits that people derive from nature. People have drastically altered the earth’s land surface in the pursuit of those ecosystem services that have been ascribed market value, while at the same time eroding biodiversity and non-market ecosystem services. The science required to inform a more balanced vision for land-cover change in the future is rapidly developing, but critical questions remain unanswered regarding how to quantify ecosystem services and ascribe value to them, and how to coordinate efforts to safeguard multiple …

Bottom-Up Adaptive Management And Stakeholder Participation For Clean Water And Healthy Soils In A Complex Social-Ecological System, Sarah Coleman

Graduate College Dissertations and Theses

Protection of water resources in a changing climate depends on bottom-up stewardship and adaptive management. From the ground up, a vital component is maintaining soil ecosystem services that regulate water, recycle nutrients, sequester carbon, provide food, and other benefits. Interacting spatial, social, and physical factors determine agricultural and stormwater management, and their impact on water. This dissertation explores these dimensions within a complex social-ecological system. The first chapter evaluates a participatory process to elicit solutions to complex environmental problems across science, policy, and practice. The second chapter studies on-farm soil assessment and its role in informing management decisions and supporting …

Consumer Engagement With Efficient And Renewable Energy Technology: Case Studies On Smart Meter Utilization And Support For A Community Anaerobic Biodigester System In Vermont, Samantha Whitney Lewandowski

Graduate College Dissertations and Theses

Residential electricity consumption in the United States has many adverse impacts, such as greenhouse gas emissions, dependence on fossil fuels, and costs. Efficient and renewable energy technologies have the potential to help mitigate some of these impacts, but appear to be under-utilized in the United States. One major barrier to expanding the deployment of these kinds of technologies and maximizing the benefits they can provide is a lack of consumer engagement. The overall purpose of this thesis is to better understand the extent to which efficient and renewable energy technologies are being engaged with and what factors may influence such …

From Sea To Lake: The Depositional History Of Saint Albans Bay, Vt, Usa, Matthew Kraft

Graduate College Dissertations and Theses

Sediment accumulated in lakes stores valuable information about past environments and paleoclimatological conditions. Cores previously obtained from Saint Albans Bay, located in the Northeast Arm of Lake Champlain, VT record the transition from the Champlain Sea to Lake Champlain. Belrose (2015) documented the presence of a peat horizon separating the sediments of the Champlain Sea from those of Lake Champlain. Initially, this layer was thought to comprise the transition from the marine environment of the Champlain Sea to a freshwater wetland. However, based on the results from this study, the transition between marine and freshwater conditions is thought to be …

Cargo Transport By Myosin Va Molecular Motors Within Three-Dimensional In Vitro Models Of The Intracellular Actin Cytoskeletal Network, Andrew Thomas Lombardo

Graduate College Dissertations and Theses

Intracellular cargo transport involves the movement of critical cellular components (e.g. vesicles, organelles, mRNA, chromosomes) along cytoskeletal tracks by tiny molecular motors. Myosin Va motors have been demonstrated to play a vital role in the transport of cargos destined for the cell membrane by navigating their cargos through the three-dimensional actin networks of the cell. Transport of cargo through these networks presents many challenges, including directional and physical obstacles which teams of myosin Va-bound to a single cargo must overcome. Specifically, myosin Va motors are presented with numerous actin-actin intersections and dense networks of filaments which can act as a …

Networks, (K)Nots, Nucleotides, And Nanostructures, Ada Morse

Graduate College Dissertations and Theses

Designing self-assembling DNA nanostructures often requires the identification of a route for a scaffolding strand of DNA through the target structure. When the target structure is modeled as a graph, these scaffolding routes correspond to Eulerian circuits subject to turning restrictions imposed by physical constraints on the strands of DNA. Existence of such Eulerian circuits is an NP-hard problem, which can be approached by adapting solutions to a version of the Traveling Salesperson Problem. However, the author and collaborators have demonstrated that even Eulerian circuits obeying these turning restrictions are not necessarily feasible as scaffolding routes by giving examples of …

Genetic And Demographic Consequences Of Lake And River Habitat Fragmentation On Fishes In Vermont, Peter T. Euclide

Graduate College Dissertations and Theses

Globally, habitat fragmentation has had a major impact on the conservation and management of many species and is one of the primary causes of species extinction. Habitat fragmentation is loosely defined as a process in which a continuous habitat is reduced to smaller, disconnected patches as the result of habitat loss, restriction of migration or the construction of barriers to movement. Aquatic systems are particularly vulnerable to habitat fragmentation, and today an estimated 48% of rivers are fragmented worldwide. My dissertation evaluates how habitat fragmentation has influenced the populations of four different species of fish in the Lake Champlain basin. …

The Progressive Evolution Of The Champlain Thrust Fault Zone: Insights From A Structural Analysis Of Its Architecture, Matthew Merson

Graduate College Dissertations and Theses

Near Burlington, Vermont, the Champlain Thrust fault placed massive Cambrian dolostones over calcareous shales of Ordovician age during the Ordovician Taconic Orogeny. Although the Champlain Thrust has been studied previously throughout the Champlain Valley, the architecture and structural evolution of its fault zone have never been systematically defined. To document these fault zone characteristics, a detailed structural analysis of multiple outcrops was completed along a 51 km transect between South Hero and Ferrisburgh, Vermont.

The Champlain Thrust fault zone is predominately within the footwall and preserves at least four distinct events that are heterogeneous is both style and slip direction. …