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Nitrogen Dynamics And Retention In The River Network Of A Tropical Forest, Luquillo Mountains, Puerto Rico, Richard Brereton

Doctoral Dissertations

This dissertation identifies gaps in the scientific understanding of nutrient cycling, particularly nitrogen (N) cycling, in streams and riparian zones of tropical montane forests, and addresses several of those gaps with original field-based research using study watersheds in the Luquillo Mountains of Puerto Rico as the model system. The Luquillo Mountains have features typical of mature montane tropical forests, such as high background N concentrations in streams and groundwater relative to streams in other biomes. As a USDA Forest Service Experimental Forest, the Luquillo Mountains are accessible to researchers and have abundant monitoring and experimental datasets from which to build …

Surface Chemisty Study Of Monazite Flotation In Coal Refuse Systems, Wencai Zhang

Theses and Dissertations--Mining Engineering

Rare earth mineral recovery from alternative resources such as coal and coal byproducts is increasingly important to provide an opportunity for economic recovery from U.S. sources. Currently, China produces the majority of the 149,000 tons of rare earth elements used annually worldwide of which the U.S. imports 11% or around 16,000 tons. There are no significant mining operations producing rare earth elements in the U.S. However, there are many U.S. sources containing rare earth minerals such as monazite including heavy mineral sand and phosphate operations. Monazite mineral particles of a few microns have also been detected in Fire Clay seam …

Working As Partners: Course Development By A Student–Teacher Team, Charlotta Bengtson, Mikaela Ahlkvist, William Ekeroth, Astrid Nilsen-Moe, Nathalie Proos Vedin, Katerina Rodiuchkina, Sofie Ye, Marcus Lundberg

International Journal for the Scholarship of Teaching & Learning

A first-year undergraduate course at Uppsala University has been redesigned in a process exploring different levels of student participation. In the first part of the project, the student voice was heard through interviews focusing on the role of the course in the degree program. In the second part, a student-teacher team was formed to develop course curriculum and teaching material in partnership. Among the implemented changes were new seminars focusing on conceptual understanding, redesign of all lectures to include active student participation, and a change of the course literature. The redesigned course significantly increased student satisfaction compared to previous years. …

Charles Holmes Herty Papers, Zach S. Henderson Library Special Collections

Finding Aids

Collection contains notebooks, photographs, and published material concerning Charles Homes Herty's 1901 experiments that resulted in the turpentine (or Herty) cup. The experiments were partly conducted on what later became the Georgia Southern University’s Statesboro campus. Includes typescript of "Charles Holmes Herty in Statesboro," by Maxwell Taylor Courson.

Find this collection in the University Libraries' catalog.

Distribution, Composition And Functions Of Gelatinous Tissues In Deep-Sea Fishes, Mackenzie E. Gerringer, Jeffrey C. Drazen, Thomas D. Linley, Adam P. Summers, Alan J. Jamieson, Paul H. Yancey

Biology

Many deep-sea fishes have a gelatinous layer, or subdermal extracellular matrix, below the skin or around the spine. We document the distribution of gelatinous tissues across fish families (approx. 200 species in ten orders), then review and investigate their composition and function. Gelatinous tissues from nine species were analysed for water content (96.53 ± 1.78% s.d.), ionic composition, osmolality, protein (0.39 ± 0.23%), lipid (0.69 ± 0.56%) and carbohydrate (0.61 ± 0.28%). Results suggest that gelatinous tissues are mostly extracellular fluid, which may allow animals to grow inexpensively. Further, almost all gelatinous tissues floated in cold seawater, thus their lower …

Water Quality And Physical Hydrogeology Of The Amarapura Township, Mandalay, Myanmar, Michael Grzybowski

Graduate Research Theses & Dissertations

Mandalay is a major city in central Myanmar with a high urban population that lacks a wastewater management system, a solid waste disposal process, and access to treated drinking water. The purpose of this study is to investigate the groundwater quality of local dug and tube wells, determine quantitative data on characteristics of the Amarapura Aquifer, and compare seasonal variations in groundwater flow and quality. Major ion chemistry data was collected during the dry and wet seasons, and analyzed using ion chromatography to identify indicators of wastewater contamination to the shallow aquifer and compare seasonal variations in groundwater chemistry. An …

Universality And Chaoticity In Ultracold K+Krb Chemical Reactions, J. F.E. Croft, C. Makrides, M. Li, A. Petrov, B. K. Kendrick, Balakrishnan Naduvalath, S. Kotochigova

Chemistry and Biochemistry Faculty Research

A fundamental question in the study of chemical reactions is how reactions proceed at a collision energy close to absolute zero. This question is no longer hypothetical: quantum degenerate gases of atoms and molecules can now be created at temperatures lower than a few tens of nanokelvin. Here we consider the benchmark ultracold reaction between, the most-celebrated ultracold molecule, KRb and K. We map out an accurate ab initio ground-state potential energy surface of the K2Rb complex in full dimensionality and report numerically-exact quantum-mechanical reaction dynamics. The distribution of rotationally resolved rates is shown to be Poissonian. An analysis of …

Evans Syndrome Complicated By Intratubular Hemoglobin Cast Nephropathy, Ivan Gonzalez, Rehan Rais, Joseph P. Gaut, Louis P. Dehner

Open Access Publications

No abstract provided.

Differences In Survival Times, By Gender, Among Those Diagnosed With Necrotizing Fasciitis, Ashley Elizabeth Hill

Walden Dissertations and Doctoral Studies

Necrotizing fasciitis infections have high mortality rates especially when treatment is delayed. Despite the abundance of research in many areas of necrotizing fasciitis infection, there are limited and conflicting studies focusing on gender-related outcomes for those diagnosed and died with necrotizing fasciitis infection. The purpose of this study was to determine the association that gender plays on survival time of patients who have been diagnosed with necrotizing fasciitis using a cross-sectional study design. Succeeding the conceptual design of the life course model, the research question tested whether there was a significant difference in survival time between the genders while in …

Frontiers In Otolith Chemistry: Insights, Advances And Applications, B. D. Walther, K. E. Limburg, C. M. Jones, J. J. Schaffler

OES Faculty Publications

The rapid proliferation of publications employing chemical assays of fish hard parts, and otoliths in particular, has led to many novel insights into the migration patterns, life history strategies and mixed stock dynamics of fishes across the globe (Campana et al., 2000; Elsdon et al., 2008; Walther & Limburg, 2012). These insights include uncovering diverse migratory strategies within species and populations (Kerr et al., 2009; Hogan et al., 2014; Schoen et al., 2016), quantifying rates of mixing among stocks across management boundaries (Rooker et al., 2008; Walther & Thorrold, 2010) and estimating the relative …

Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler

OES Faculty Publications

Classification method performance was evaluated using otolith chemistry of juvenile Atlantic menhaden Brevoortia tyrannus when assumptions of data normality were met and were violated. Four methods were tested [linear discriminant function analysis (LDFA), quadratic discriminant function analysis (QDFA), random forest (RF) and artificial neural networks (ANN)] using computer simulation to determine their performance when variable-group means ranged from small to large and their performance under conditions of typical skewness to double the amount of skewness typically observed. Using the kappa index, the parametric methods performed best after applying appropriate data transformation, gaining 2% better performance with LDFA performing slightly better …

A Qualitative Comparison Of General Chemistry And Advanced Placement Chemistry Students' Misconceptions Regarding Solution Chemistry, Megan J. Vandersee

Dissertations and Theses @ UNI

This study focused on identifying misconceptions which high school AP and collegiate general chemistry students hold with regards to solution chemistry topics and comparing the misconceptions held by each student group. Previous research has found that misconceptions can greatly impact students’ understanding of material and have a negative impact on student learning. However, not all solution chemistry topics had been explored in previous research. In addition, it has been suggested that collegiate students have reached a higher level of cognitive development as they are older and more advanced in their studies. If this is the case, one could assume that …

2016 Fall - Commencement Program, Office Of The Registrar, East Tennessee State University

ETSU Commencement Ceremonies and Programs

No abstract provided.

Mole Street Journal, December 2016, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Microstructural Evolution During The Homogenization Heat Treatment Of 6xxx And 7xxx Aluminum Alloys, Pikee Priya

Open Access Dissertations

Homogenization heat treatment of as-cast billets is an important step in the processing of aluminum extrusions. Microstructural evolution during homogenization involves elimination of the eutectic morphology by spheroidisation of the interdendritic phases, minimization of the microsegregation across the grains through diffusion, dissolution of the low-melting phases, which enhances the surface finish of the extrusions, and precipitation of nano-sized dispersoids (for Cr-, Zr-, Mn-, Sc-containing alloys), which inhibit grain boundary motion to prevent recrystallization. Post-homogenization cooling reprecipitates some of the phases, changing the flow stress required for subsequent extrusion. These precipitates, however, are deleterious for the mechanical properties of the alloy …

Computational Quantum Chemistry Studies Of The Stabilities Of Radical Intermediates Formed During The Oxidation Of Melatonin, Constance E. Warden

Electronic Theses and Dissertations

Melatonin, a nontoxic natural antioxidant, is of interest as a possible spin trap for use in spectroscopic methods to observe and identify short-lived free radicals, which have been linked to oxidative stress that may result in serious health problems. However, the reaction mechanisms for the oxidation of melatonin to form the product N¹-acetyl-N²-formyl-5-methoxykynuramine are still not well understood. Computational quantum chemistry studies have been done on four proposed reaction mechanisms, involving the following major intermediate structures: a dioxetane, an epoxide, a melatonin radical cation, and a spin radical adduct. Molecular geometries were optimized at the …

Is It Scholarly? A Lesson Plan For Collaborative Chemistry Information Literacy, Barbara C. Harvey

Books and Contributions to Books

This chapter describes a lesson plan that incorporates information literacy into an introductory chemistry course. The learning outcomes of the activity include becoming familiar with the peer-review process, knowing how to locate original research articles based on “clues” in a general news article, and differentiating between popular and scholarly periodicals. Students work in small groups in a collaborative classroom setting. The activities of the lesson plan are mapped to the Framework for Information Literacy for Higher Education. The lesson plan is supported by a literature review outlining the importance of collaborative, active learning in STEM courses, and highlights the correlation …

Continuing The Career: An Oral History Of An Emeritus Professor, Kimberly Read

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to describe and explain the perspectives of a professor emeritus regarding his life experiences in the discipline of chemistry and in a career dedicated to research, service and teaching. Another purpose, interwoven within the perspective of this one individual, was to explore the potential influence a professor emeritus can have on his institution, and the impact the institution, its changing culture, and its shifting priorities may have on a member of the professoriate dedicated to this chosen career path. The research guiding questions for this study were: (a) What elements of this professor emeritus’ …

The Role Of Low-Energy (≤ 20 Ev) Electrons In Astrochemistry, Michael C. Boyer, Nathalie Rivas, Audrey A. Tran, Clarissa A. Verish, Christopher R. Arumainayagam

Faculty Research and Scholarship

UV photon-driven condensed phase cosmic ice reactions have been the main focus in understanding the extraterrestrial synthesis of complex organic molecules. Low-energy (≤20 eV) electron-induced reactions, on the other hand, have been largely ignored. In this article, we review studies employing surface science techniques to study low-energy electron-induced condensed phase reactions relevant to astrochemistry. In particular, we show that low-energy electron irradiation of methanol ices leads to the synthesis of many of the same complex molecules formed through UV irradiation. Moreover, our results are qualitatively consistent with the hypothesis that high-energy condensed phase radiolysis is mediated by low-energy electron-induced reactions. …

Mole Street Journal, October 2016, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Measurements By Controlled Meteorological Balloons In Coastal Areas Of Antarctica, Lars R. Hole, Alexis Pérez Bello, Tjarda J. Roberts, Paul B. Voss, Timo Vihma

Engineering: Faculty Publications

An experiment applying controlled meteorological (CMET) balloons near the coast of Dronning Maud Land, Antarctica, in January 2013 is described. Two balloons were airborne for 60 and 106 hours with trajectory lengths of 885.8 km and 2367.4 km, respectively. The balloons carried out multiple controlled soundings on the atmospheric pressure, temperature and humidity up to 3.3 km. Wind speed and direction were derived from the balloon drift. Observations were compared with radiosonde sounding profiles from the Halley Research Station, and applied in evaluating simulations carried out with the weather research and forecasting (WRF) mesoscale atmospheric model. The most interesting feature …

Pushing And Pulling Sara: A Case Study Of The Contrasting Influences Of High School And University Experiences On Engineering Agency, Identity, And Participation, Allison Godwin, Geoff Potvin

School of Engineering Education Faculty Publications

This manuscript reports on a longitudinal case study of how one woman, Sara, who had previously considered dropping out of high school authored strong mathematics and science identities and purposefully exhibited agency through her experiences in high school science. These experiences empowered her to choose an engineering major in college; however, her introductory university engineering experiences ultimately pushed her out of engineering. Drawing on critical agency theory, we argue that by paying careful attention to how and why women author their identities and build agency through their experiences in high school, we may gain insight into why women may choose …

Theoretical Study Of Photoelectrochemical Reactions And Ec-Sers On Spr Metallic Electrodes Of Silver And Gold, Yuan-Fei Wu, Ran Pang, Meng Zhang, Jian-Zhang Zhou, Bin Ren, Zhong-Qun Tian, De-Yin Wu

Journal of Electrochemistry

At present photoelectrochemistry has received much concern back to nanostructures of noble metals from semiconductor electrodes. This is due to the surface plasmon resonance (SPR) effect of metallic nanostructures, which can effectively convert the far-field light to the near-field light and concentrate the photonic energy to the local surface area with high energy density. Thus, the different enhancement mechanisms, such as the local optical field enhancement, the formation of light generated hot carriers (hot electron-hole pairs), or the photothermal effect, have been proposed in literatures. On the basis of the SPR enhancement effect, the surface-enhanced Raman spectroscopy (SERS) can be …

Mole Street Journal, August 2016, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

August 2016 Commencement Program, Bowling Green State University

Commencement Programs

No abstract provided.

Development Of Biocompatible Small-Molecule Spacers As Metal Oxide Nanoparticles' Stabilizing Agents, Galina Goloverda, Huy Do, Ezinne U. Agwaramgbo, Anastasia Labeaud, Rajesh Komati, Vladimir Kolesnichenko

Nanotechnology in Medicine: From Molecules to Humans

Development and study of the magnetic nanoparticles for biological and clinical applications remains one of the challenging research areas in chemistry and materials science. The performance of these particles as, for example, drug delivery, MRI, hyperthermia or cell tracking agents, depends on their magnetic susceptibility. Their ability to form stable aqueous colloids, the mobility, and diffusion properties in biological media, rely on organic coating, which is usually composed of hydrophilic biocompatible polymers such as dextrans or poly(ethylene glycol)s. Some areas of biomedical imaging, labeling and delivery application can benefit from magnetic nanoparticles with higher mobility and penetration, stronger interaction with …

Chemistry, Saint Mary's College Of California

Undergraduate Academic Catalog

No abstract provided.

Quantum Dot Metrics For Preparative Chemistry And Fluorescence Applications, Yi Shen

Theses and Dissertations

Colloidal semiconductor quantum dots (QDs) are considered to be a promising candidate for bio-imaging and solar cells because of their extraordinary photo-physical properties. The ultimate goal of this dissertation is to design a reliable matrix and a reproducible method to prepare QDs-based biocompatible probe for fluorescence applications. Synthesis of quantum dots requires a large amount of ligands to improve the stability at high temperature. However, for further application and surface modification of QDs, excess ligands must be removed. In this dissertation, I will first describe using gel permeation chromatography (GPC) as a media to purify different types of QDs. A …

Development And Implementation Of Problem-Based Chemistry Experiments For Engineering Students In A Multi-Disciplinary Course, Tiffany Hesser, Stephanie R. Bunyea

Chemistry and Chemical Engineering Faculty Publications

This paper will describe the implementation and continuing development of five problem based laboratory experiments in a general chemistry course designed specifically for multiple disciplines of engineering students at the University of New Haven. The Problem Based Laboratory Experiments (PBLE) were developed to provide students with the opportunity to perform and develop experimental procedures working in interdisciplinary teams, while achieving a greater understanding of the role of chemistry in engineering fields. In each PBLE, students first complete a traditional chemistry experiment to gain an understanding of the chemical concepts and to become familiar with executing a written procedure with a …

Mole Street Journal, June 2016, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.