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Microporous Organic Polymers: Synthesis And Post Synthetic Modifications, Phillip Andrew Kerneghan 2010 Wilfrid Laurier University

Microporous Organic Polymers: Synthesis And Post Synthetic Modifications, Phillip Andrew Kerneghan

Theses and Dissertations (Comprehensive)

Microporous solids are an important class of materials that have been studied extensively. Newer to this field are Microporous Organic Polymers (MOPs) which are networks constructed from smaller organic building blocks and exhibit large surface areas, small pore sizes and low densities. It is due to these characteristics that MOPs have attracted attention because of their potential use in applications such as catalysis, chemical separations and gas storage.

In this thesis is described the synthesis of two novel MOPs, the first of which being a network based on benzenediboronic acid and triptycene building blocks linked together by boronate esters. This …


Plant Isotopes As Indicators Of N Cycling Processes In Agricultural Fields, Eric Thuss 2010 Wilfrid Laurier University

Plant Isotopes As Indicators Of N Cycling Processes In Agricultural Fields, Eric Thuss

Theses and Dissertations (Comprehensive)

When nitrogen (N) availability exceeds biological demand, excess N, especially nitrate (NO3), may subsequently pollute ground and surface water. Agricultural practices in Southern Ontario typically supplement soils with organic and inorganic nutrients to aid in crop development, and employ various management techniques to limit nutrient loss. Excess N has several potential fates, which are controlled by the net effects of numerous N cycling reactions in the soil that are often difficult to measure directly. N cycling in soils is controlled in large part by soil moisture, as it affects microbial activity and soil redox conditions. Stable isotope geochemistry …


Carbon Dioxide Exchange In A Permafrost-Dominated Boreal Wetland In The Northwest Territories, Canada, Andrea J. Kenward 2010 Wilfrid Laurier University

Carbon Dioxide Exchange In A Permafrost-Dominated Boreal Wetland In The Northwest Territories, Canada, Andrea J. Kenward

Theses and Dissertations (Comprehensive)

Northern boreal wetland complexes are substantial reservoirs for carbon and play a crucial role in both regional and global carbon budgets but they are showing significant signs of impact by climate change. This study examined the carbon dioxide flux of a high boreal wetland during the snowmelt and growing season of 2008 in Scotty Creek Basin, located near Fort Simpson (61°18'N, 121°18'W), Northwest Territories. This basin is not only responding to shifts in atmospheric temperatures, but it is also under additional pressure from increasing permafrost degradation. A dynamic closed-system chamber was used to monitor and quantify mid-day total respiration (R …


Paleolimnological Reconstruction Of Hydrologic Change In The Slave River And Great Slave Lake During The Past Millennium, Matthew Ennis 2010 Wilfrid Laurier University

Paleolimnological Reconstruction Of Hydrologic Change In The Slave River And Great Slave Lake During The Past Millennium, Matthew Ennis

Theses and Dissertations (Comprehensive)

The Slave River Delta (SRD), NWT, represents a pivotal node in the upper Mackenzie Basin watershed and is a productive northern wetland landscape with a rich natural and cultural heritage. Concerns over environmental consequences of natural and anthropogenic-driven decline in river discharge as well as climate variability have prompted hydroecological sstudies to improve understanding of how this ecosystem functions over time and space. However, long-term natural hydrological variability of the Slave River system is not well documented and needs to be further developed. In order to provide a temperal context for understanding and evaluating the impacts of climate variability and …


Rethinking Biodiversity Conservation Effectiveness And Evaluation In The National Protected Areas Systems Of Tropical Islands: The Case Of Jamaica And The Dominican Republic, Suzanne Mae Camille Davis 2010 Wilfrid Laurier University

Rethinking Biodiversity Conservation Effectiveness And Evaluation In The National Protected Areas Systems Of Tropical Islands: The Case Of Jamaica And The Dominican Republic, Suzanne Mae Camille Davis

Theses and Dissertations (Comprehensive)

Island conservation theory and practice with regard to conservation of tropical terrestrial biodiversity in protected areas systems has yet to be adequately addressed in conservation literature. This knowledge gap is identified as a key contributor to the adoption of scientific principles for in situ biodiversity conservation, and “universal” conservation and protected area management paradigms that are unsuitable for island contexts and geographical scale. The underlying assumption is that “universal” concepts of biodiversity conservation, protected areas management, and evaluation of their effectiveness are transferable to the ecological and socio-economic contexts of tropical islands. The expected outcome of this knowledge transfer is …


Littoral Cells, Longshore Transport And Wave Climate: An Examination Of Littoral Transport Along The Western Shore Of Prince Edward County, Ontario, Jayson A. Childs 2010 Wilfrid Laurier University

Littoral Cells, Longshore Transport And Wave Climate: An Examination Of Littoral Transport Along The Western Shore Of Prince Edward County, Ontario, Jayson A. Childs

Theses and Dissertations (Comprehensive)

This study discusses the wave climate and potential littoral transport along the western shore of Prince Edward County approximately two hours east of Toronto along the northern shoreline of Lake Ontario. The limestone headlands and barrier bars of the western coast are exposed toward a southwesterly fetch of approximately 200 km that can produce large offshore wave heights of 2–5 m. The wave model STWAVE was used to transform a standard set of wave conditions developed from recent hindcast data to examine fair weather, storm and extreme conditions for five directions between south and west-northwest along the shore. The resulting …


Project Explorations And Student Learning In Geometry, Verna Marie Richard 2010 Louisiana State University and Agricultural and Mechanical College

Project Explorations And Student Learning In Geometry, Verna Marie Richard

LSU Master's Theses

The purpose of this study was to examine the structural framework of the EBRPSS 8th Grade Mathematics Comprehensive Curriculum and to compare its effectiveness to a set of project-based lessons that I created for “Unit 4: Measurement and Geometry”. Two classes participated in this study. Pretest and Posttest scores were analyzed to determine if there was a significant advantage to using my supplements. Results of the analysis revealed that there was an advantage to using the supplements, in spite of the time shortage. Hopefully, the supplements implemented in this study will serve as a model for teaching “Unit 4: Measurement …


Seventh-Grade Curriculum In Probability (A Guide For Teachers), David Nganga Njenga 2010 Louisiana State University and Agricultural and Mechanical College

Seventh-Grade Curriculum In Probability (A Guide For Teachers), David Nganga Njenga

LSU Master's Theses

A review of the literature indicates that teachers try to make connections between experimental and theoretical probabilities while teaching their students, but these connections are often not very clear. This greatly increases misconceptions students have about probability. This thesis presents a treatment of teaching probability that is geared for seventh grade and intended to minimize the misconceptions that both teachers and students may have. We present a concise mathematical exposition of finite probability models as well as collection of examples and activities, so as to help teachers and students organize their thinking and minimize misconceptions. The various examples and activities …


Positive Solutions Of The (N-1, 1) Conjugate Boundary Value Problem, Bo Yang 2010 Kennesaw State University

Positive Solutions Of The (N-1, 1) Conjugate Boundary Value Problem, Bo Yang

Faculty Publications

We consider the (n - 1, 1) conjugate boundary value problem. Some upper estimates to positive solutions for the problem are obtained. We also establish some explicit sufficient conditions for the existence and nonexistence of positive solutions of the problem.


Investigating The Effectiveness Of Informal Science Education Through Quantitative And Qualitative Analysis: Ocean Commotion, Catherine Angela Sutera 2010 Louisiana State University and Agricultural and Mechanical College

Investigating The Effectiveness Of Informal Science Education Through Quantitative And Qualitative Analysis: Ocean Commotion, Catherine Angela Sutera

LSU Master's Theses

Informal science education serves as an important source for science education for both individuals and school groups. However, the effectiveness of school visits to informal science education events outside of either museums or science centers has received little investigation. This study explores the short-term effects of a hands-on learning experience on students’ attitude and content knowledge. Specifically, it investigates the impact of Ocean Commotion, a one-day event where exhibitors present information and hands-on demonstrations about marine environments and products, especially those important to Louisiana. Pre-tests were utilized to document students’ initial knowledge of and attitude toward wetlands and the ocean, …


Optimal Control And Nonlinear Programming, Qingxia Li 2010 Louisiana State University and Agricultural and Mechanical College

Optimal Control And Nonlinear Programming, Qingxia Li

LSU Doctoral Dissertations

In this thesis, we have two distinct but related subjects: optimal control and nonlinear programming. In the first part of this thesis, we prove that the value function, propagated from initial or terminal costs, and constraints, in the form of a differential equation, satisfy a subgradient form of the Hamilton-Jacobi equation in which the Hamiltonian is measurable with respect to time. In the second part of this thesis, we first construct a concrete example to demonstrate conjugate duality theory in vector optimization as developed by Tanino. We also define the normal cones corresponding to Tanino's concept of the subgradient of …


Non-Axisymmetric Instabilities In Self-Gravitating Tori Around Black Holes, And Solving Einstein Constraints With Superconvergent Finite Element Methods, Oleg Korobkin 2010 Louisiana State University and Agricultural and Mechanical College

Non-Axisymmetric Instabilities In Self-Gravitating Tori Around Black Holes, And Solving Einstein Constraints With Superconvergent Finite Element Methods, Oleg Korobkin

LSU Doctoral Dissertations

This thesis contains results on two related projects. In the first project, we explore non-axisymmetric instabilities in general relativistic accretion disks around black holes. Such disks are created as transient structures in several astrophysical scenarios, including mergers of compact objects and core collapse of massive stars. These disks are suggested for the role of cenral engines of gamma-ray bursts. We address the stability of these objects against the runaway and non-axisymmetric instabilities in the three-dimensional hydrodynamical fully general relativistic treatment. We explore three slender and moderately slender disk models with varying disk-to-black hole mass ratio. None of the models that …


Pharmaceutical Compounds In Treatment Wetlands: Potential Removal And Effects On Microbial Processes, Jeremy Landon Conkle 2010 Louisiana State University and Agricultural and Mechanical College

Pharmaceutical Compounds In Treatment Wetlands: Potential Removal And Effects On Microbial Processes, Jeremy Landon Conkle

LSU Doctoral Dissertations

active compounds (PhACs) have been detected in the aquatic environment as a result of loading from various sources. In Louisiana, USA, many municipalities treat wastewater using natural systems, such as lagoons and wetlands, rather than using conventional wastewater treatment technologies and may discharge PhACs into the environment. These treatment systems are not designed to remove PhACs from wastewater, nor is it currently a regulatory requirement. Research on the fate of PhACs in the environment is needed to understand impacts on Louisiana’s important coastal system. Wastewater sampling for PhACs at the Mandeville, LA wastewater treatment plant (WWTP) determined that this system …


Homogenization Of Nonlinear Partial Differential Equations, Silvia Jiménez 2010 Louisiana State University and Agricultural and Mechanical College

Homogenization Of Nonlinear Partial Differential Equations, Silvia Jiménez

LSU Doctoral Dissertations

This dissertation is concerned with properties of local fields inside composites made from two materials with different power law behavior. This simple constitutive model is frequently used to describe several phenomena ranging from plasticity to optical nonlinearities in dielectric media. We provide the corrector theory for the strong approximation of fields inside composites made from two power law materials with different exponents. The correctors are used to develop bounds on the local singularity strength for gradient fields inside microstructured media. The bounds are multiscale in nature and can be used to measure the amplification of applied macroscopic fields by the …


Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis 2010 Louisiana State University and Agricultural and Mechanical College

Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis

LSU Doctoral Dissertations

With the expansion of the human population and associated industries there is a concomitant increase in both resource utilization and the production of waste and deleterious by-products. Mercury is a naturally-occurring toxic metal with a complicated and unique biogeochemical cycle, and is often a contaminant of ecotoxicological concern in unindustrialized aquatic habitats. The research described herein was designed to elucidate multiple aspects regarding the behavior of mercury in oligohaline wetland habitats, particularly with respect to edaphic and vegetative effects, through a monitoring and characterization study as well as a series of manipulative experiments. The observational study, conducted in the wetlands …


Diatom Stratigraphy Defining Ice Sheet Grounding Chronology, Ross Sea, Antarctica, Juan Manuel Chow 2010 Louisiana State University and Agricultural and Mechanical College

Diatom Stratigraphy Defining Ice Sheet Grounding Chronology, Ross Sea, Antarctica, Juan Manuel Chow

LSU Doctoral Dissertations

Evidence of Antarctic ice sheet behavior and paleoenvironment is often approached from proxy records because there is a dearth of direct records from Antarctica itself. The studies presented here seek to augment our knowledge of translations of the West Antarctic Ice Sheet’s (WAIS) marine termination based on direct biostratigraphic evidence. Diatom analyses were conducted from two areas of Ross Sea, Antarctica. In the first study, diatoms were used to constrain the age of diamictons from five seismic units in the Eastern Basin and thus expand our knowledge of WAIS behavior during the Southern Hemisphere Last Glacial Maximum (LGM). All five …


Volcanological And Petrogenetic Characteristics Of Komatiites Of The 3.3 Ga Saw Mill Complex, Weltevreden Formation, Barberton Greenstone Belt, South Africa, Matthew Stephen Huber 2010 Louisiana State University and Agricultural and Mechanical College

Volcanological And Petrogenetic Characteristics Of Komatiites Of The 3.3 Ga Saw Mill Complex, Weltevreden Formation, Barberton Greenstone Belt, South Africa, Matthew Stephen Huber

LSU Master's Theses

The Saw Mill Complex (SMC) is a 1275 m thick layered komatiitic sequence in the 3.3 Ga Weltevreden Formation, uppermost stratigraphic unit of the Onverwacht Group in the northern part of the Barberton Greenstone Belt, South Africa. A series of ultramafic complexes in the Weltevreden Formation have been interpreted as layered ultramafic intrusions, consisting of thick, layered ultramafic units of peridotite, pyroxenite, dunite, and gabbro. However, recent work on the Pioneer complex of the Weltevreden Formation has demonstrated an extrusive origin of komatiites and tuffs. The Weltevreden Formation has been less studied than other Onverwacht Group units. It is likely …


Physical And Microbial Responses Of Dredged Sediment To Two-Soil-Stabilizing Amendments, Xanthan Gum And Guar Gum, For Use In Coastal Wetland Restoration, Lauren Land 2010 Louisiana State University and Agricultural and Mechanical College

Physical And Microbial Responses Of Dredged Sediment To Two-Soil-Stabilizing Amendments, Xanthan Gum And Guar Gum, For Use In Coastal Wetland Restoration, Lauren Land

LSU Master's Theses

In wetland sediments, organic matter provides a substrate for microbial activity. During metabolism, microbes release extracellular polymeric substances, which accumulate to bind soil particles. A similar concept can be implemented on a large scale to reduce wetland loss in Louisiana. Hypothetically, hydraulically dredged sediment can be amended with polymer and deposited on subsiding marshes as a restoration method where the polymer increases sediment stabilization until plants become established. This lab study focused on investigating the influence of natural polymer additions on particle aggregation to increase sediment stability and the effects on microbial activity. Sediments from three sites (i.e. freshwater, intermediate, …


A Dynamic Physical Model For Soil Temperature And Water In Taylor Valley, Antarctica, H. W. Hunt, Andrew G. Fountain, Peter T. Doran, Hassan J. Basagic 2010 Colorado State University - Fort Collins

A Dynamic Physical Model For Soil Temperature And Water In Taylor Valley, Antarctica, H. W. Hunt, Andrew G. Fountain, Peter T. Doran, Hassan J. Basagic

Geography Faculty Publications and Presentations

We developed a simulation model for terrestrial sites including sensible heat exchange between the atmosphere and ground surface, inter- and intra-layer heat conduction by rock and soil, and shortwave and longwave radiation. Water fluxes included snowmelt, freezing/thawing of soil water, soil capillary flow, and vapour flows among atmosphere, soil, and snow. The model accounted for 96-99% of variation in soil temperature data. No long-term temporal trends in soil temperature were apparent. Soil water vapour concentration in thawed surface soil in summer often was higher than in frozen deeper soils, leading to downward vapour fluxes. Katabatic winds caused a reversal of …


Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron 2010 Louisiana State University and Agricultural and Mechanical College

Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron

LSU Doctoral Dissertations

Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region is most sensitive to nest success, and nest success is most strongly influenced by predation. I evaluated the efficacy of reducing predator populations to improve nest success and increase local breeding populations of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005−2008. I also examined potential territorial limitations on local population growth for mallards. Trappers annually removed an average of 245 predators per trapped site. I monitored 7,489 nests on 7 trapped and 5 nontrapped sites, …


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