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Western Michigan University

Masters Theses

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Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link Aug 2023

Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link

Masters Theses

Concentrations, compositions, and variability of Per- and Polyfluoroalkyl Substances (PFAS) in sewage sludge are characterized using an extensive dataset of 350 samples from 190 wastewater treatment plants (WWTPs) across Michigan. All samples are comprised of final treated sewage sludge generated at the end of the wastewater treatment process. Concentrations of Σ24 PFAS are log normally distributed with a range of 1 to 3200 ng/g dry wt. and of average 108 ± 277 ng/g dry wt. Compounds with carboxyl and sulfonic functional groups comprised 29% and 71% of Σ24 PFAS concentrations, respectively, on average. Primary sample variability is associated …


Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link Aug 2023

Per- And Polyfluoroalkyl Substances (Pfas) In Treated Sewage Sludge From Michigan Wastewater Treatment Plants, Garrett Wesley Link

Masters Theses

Concentrations, compositions, and variability of Per- and Polyfluoroalkyl Substances (PFAS) in sewage sludge are characterized using an extensive dataset of 350 samples from 190 wastewater treatment plants (WWTPs) across Michigan. All samples are comprised of final treated sewage sludge generated at the end of the wastewater treatment process. Concentrations of Σ24 PFAS are log normally distributed with a range of 1 to 3200 ng/g dry wt. and of average 108 ± 277 ng/g dry wt. Compounds with carboxyl and sulfonic functional groups comprised 29% and 71% of Σ24 PFAS concentrations, respectively, on average. Primary sample variability is associated with …


Copper-Indazolate Nanojars: Synthesis And Characterization, Nicholas Alexander Rudell Jun 2023

Copper-Indazolate Nanojars: Synthesis And Characterization, Nicholas Alexander Rudell

Masters Theses

The field of synthetic supramolecular chemistry has exploded since the first syntheses of crown ethers by Charles Pedersen in the 1960s, leading to further development in the area of macrocycles and incorporation into a vast array of metal-organic structures. Supramolecular chemistry came to the forefront of science with the 1987 Nobel Prize in Chemistry, awarded jointly to Donald J. Cram, Jean-Marie Lehn, and Charles Pedersen “for their development and use of molecules with structure-specific interactions of high selectivity.”

Nanojars are supramolecular metal-organic complexes with a high affinity for hydrophilic anions and can efficiently transfer such anions from water into organic …


Concept Validation: Collecting Composite Samples To Understand The Presence Of Per- And Polyfluoroalkyl Substances (Pfas) In Michigan Forested Areas, Nicole Renee Sanabria Apr 2023

Concept Validation: Collecting Composite Samples To Understand The Presence Of Per- And Polyfluoroalkyl Substances (Pfas) In Michigan Forested Areas, Nicole Renee Sanabria

Masters Theses

This research discusses the results of a state-wide study conducted by The Michigan Department of Environment, Great Lakes, and Energy to assess the presence of PFAS in shallow soils of state-owned forested areas in Michigan utilizing a composite sampling method. One sample collected from each of Michigan’s 83 counties reveals the presence of PFAS in all but one sample, with total PFAS concentrations ranging from non-detect to 2.016 μg/kg (dry weight). PFOS is generally detected at the highest concentrations, ranging from non-detect to 0.88 μg/kg, followed by PFBA, with concentrations ranging from non-detect to 0.69 μg/kg, and PFOA, with concentrations …


Factors Affecting Groundwater Nitrate Concentration In Madinah Area, Saudi Arabia, Majed M. Almutairi Apr 2023

Factors Affecting Groundwater Nitrate Concentration In Madinah Area, Saudi Arabia, Majed M. Almutairi

Masters Theses

High levels of nitrate in groundwater are a serious problem in Madinah Area, Saudi Arabia. Identifying factors affecting groundwater nitrate contamination is important for managing groundwater quality. This study examined factors that have significant impacts on the high level of groundwater nitrate in Madinah Area. Factors examined included well-depth and land cover. Relationships between variables were explored using three statistical approaches: the Kruskal-Wallis test and two types of regression (ordinary least squares [OLS] and geographically weighted regression [GWR]).

Nitrate concentration data show that 73% of obtained groundwater samples exceeded the United States Environmental Protection Agency (EPA) maximum contaminant level (MCL) …


Exploring The Effects Of Tree Roots On Infiltration Process, Nazife Onaral Dec 2022

Exploring The Effects Of Tree Roots On Infiltration Process, Nazife Onaral

Masters Theses

Effects of the root structures on soil infiltration dynamics are not clearly defined. Imaging the complex tree root structures and movement of water through the root ball is a challenging task to achieve without damaging the trees and roots by conventional methods. Commonly used methods are invasive, labor-intensive, and not easily accessible. Ground Penetrating Radar (GPR) has commonly been used to characterize soil profiles and it can be a reliable tool to map complex root structures with a novel high-resolution circular data collection technique. Electrical resistivity tomography (ERT) is another reliable geophysical method to image infiltration processes by the change …


“This Isn't Working For Me. Can We Do It A Different Way?" The Lived Experiences Of Geoscience Students With Learning Disabilities, Nina Morris Dec 2022

“This Isn't Working For Me. Can We Do It A Different Way?" The Lived Experiences Of Geoscience Students With Learning Disabilities, Nina Morris

Masters Theses

The purpose of this exploratory qualitative study is to better understand the lived experiences of geoscience students with learning disabilities in their geoscience classes. Students with learning disabilities bring a unique perspective while also facing unique challenges in post-secondary education. In the literature, there is limited information on what support and teaching strategies are beneficial to this population. Undergraduate and graduate geoscience students who identify as having a learning disability from colleges and universities in the United States were recruited. Six students consented to participate in the study, and each completed a semi-structured interview. Semi-structured interviews were designed to prompt …


Kinetic And Structural Characterization Of Pseudooxynicotine Amine Oxidase From Pseudomonas Putida S16, Vishakha Choudhary Aug 2022

Kinetic And Structural Characterization Of Pseudooxynicotine Amine Oxidase From Pseudomonas Putida S16, Vishakha Choudhary

Masters Theses

Our laboratory has previously shown that nicotine oxidoreductase (NicA2), a member of the flavin-containing amine oxidase family, uses a cytochrome c protein (CycN) as its electron acceptor rather than characteristically accepted molecular oxygen. Within the Pseudomonas putida S16 genome, the nicA2 gene forms an operon with cycN and pseudooxynicotine amine oxidase (pnao), another flavin containing amine oxidase enzyme. The first two steps in the nicotine catabolism pathway are catabolized by NicA2 and Pnao. Through redox chemistry, NicA2 converts nicotine to pseudooxynicotine and Pnao converts pseudooxynicotine to 3-succinoylsemialdehyde-pyridine. In this thesis, we characterize the kinetic and structural properties of …


Autonomous Eco-Driving With Traffic Light And Lead Vehicle Constraints: An Application Of Best Constrained Interpolation, Yara Hazem Mohamed Mahmoud Apr 2022

Autonomous Eco-Driving With Traffic Light And Lead Vehicle Constraints: An Application Of Best Constrained Interpolation, Yara Hazem Mohamed Mahmoud

Masters Theses

Eco-Driving is a critical technology for improving automotive transportation efficiency. It is achieved by modifying the driving trajectory over a particular route to minimize required propulsion energy. Eco-Driving can be approached as an optimal control problem subject to driving constraints such as traffic lights and positions of other vehicles. Best interpolation in a strip is a problem in approximation theory and optimal control. The solution to this problem is a cubic spline. In this research we demonstrate the connection between Eco-Driving and best interpolation in the strip. By exploiting this connection, we are able to generate optimal Eco-Driving trajectories that …


Parallel Resource Defined Fitness Sharing: A Study On Parallel Optimizations For Niching Algorithms, Blayne A. Rogers Apr 2022

Parallel Resource Defined Fitness Sharing: A Study On Parallel Optimizations For Niching Algorithms, Blayne A. Rogers

Masters Theses

The exploitation of niches by genetic algorithms (GAs) is a computationally expensive, but effective, methodology for solving complex open problems and real-world applications. Niching, differentiated on the modality of sharing, casts problems in terms of the specific resources available. These concepts arise from the broader natural algorithms that encapsulate the ideas and theories used in artificial intelligence. In remediating the computational costs, a study on exploiting niche-defined parallel structures is performed in the contest of the resourcedefined fitness sharing (RFS) algorithm.

Sharing is a natural algorithm paradigm that emulates the use of resources within an environment or population. Defining these …


Instructor Selection And Use Of Virtual Field Experiences In College Geoscience Course, Kristen Foley Apr 2022

Instructor Selection And Use Of Virtual Field Experiences In College Geoscience Course, Kristen Foley

Masters Theses

Virtual Field Experiences (VFEs) are a growing supplement and gateway to traditional fieldwork in the geosciences. With VFEs becoming more accepted for use in college geoscience courses, how instructors find and choose VFEs for their students is critical to creating greater accessibility and future resources. VFEs that are not easily accessed by instructors may go unused, and the effort put into making them would have been wasted. This phenomenological descriptive study utilized five focus groups of college geoscience instructors in the United States. Each 1-to-1.5-hour focus group session of 3-7 participants took place on video conferencing software, which was recorded …


Quantifying Surface Water Capture By Municipal Pumping Wells In An Urban Watershed Impacted By Road Salt, Austen York Dec 2021

Quantifying Surface Water Capture By Municipal Pumping Wells In An Urban Watershed Impacted By Road Salt, Austen York

Masters Theses

The Spring Valley sub-watershed is located within the Kalamazoo Township contains Spring Valley Lake, a man-made impoundment that ultimately discharges into the Kalamazoo River. Elevated chloride levels in pumped water from the Kalamazoo Station 14 municipal wellfield, located along the shoreline of Spring Valley Lake, has resulted in less than ideal corrosivity values for the water distribution system. Specific project objectives include: (1) identifying the cause of elevated chloride, (2) assessing surface water capture by the Station 14 wellfield, and (3) characterizing of water quality in Spring Valley Lake. Monitoring along a series of sampling transects spanning the sub-watershed, focused …


Using Sedimentary Mercury Geochemistry To Evaluate The Niagara-Salina Transition, Silurian Michigan Basin, Usa, Sara Hayes Dec 2021

Using Sedimentary Mercury Geochemistry To Evaluate The Niagara-Salina Transition, Silurian Michigan Basin, Usa, Sara Hayes

Masters Theses

The Niagara-Salina boundary in the Michigan Basin is marked by an abrupt transition from carbonates to evaporites. Though the cause is uncertain, previous work suggests the onset of Salina evaporites was driven by basin restriction, but the presence of several global carbon isotope excursions (CIE) suggest a global driver. This study builds on this discussion using two relatively new geochemical proxies - elemental mercury concentrations [Hg] and Hg isotopes.

Mercury concentrations [Hg] were measured in 88 samples from the State Kalkaska #2-15 core from 6604.03 ft to 6797.42 ft. [Hg] ranges from 0.11 to 0.62 mg/kg and [Hg]/TOC from 0.038 …


Impact Of Calcium Carbonate Reactant Size And Mineralogy On Dolomite Stoichiometry, Katharine G. Rose Aug 2021

Impact Of Calcium Carbonate Reactant Size And Mineralogy On Dolomite Stoichiometry, Katharine G. Rose

Masters Theses

Dolomite is a common, diagenetic, Mg-Ca carbonate mineral. Dolomitization occurs by a dissolution-precipitation reaction between a CaCO3 precursor (calcite or aragonite) and Mg bearing fluids. The amount of Mg in dolomite, referred to as dolomite stoichiometry (mol% MgCO3), varies in natural dolomites (38-50 mol% MgCO3). Laboratory experiments have shown that dolomite stoichiometry is dependent on physiochemical factors of the diagenetic fluids (i.e., temperature, salinity, and Mg/Ca). The impact of the CaCO3 precursor on stoichiometry, however, has not been studied directly. This study tests how the CaCO3 precursor size (sieve size) and mineralogy (calcite …


On Cup-Products Of Cofibers Of Maps Between Moore Spaces, Hopf Invariant, And Lusternik-Schnirelmann Category, Marwa A.S. Mosallam Aug 2021

On Cup-Products Of Cofibers Of Maps Between Moore Spaces, Hopf Invariant, And Lusternik-Schnirelmann Category, Marwa A.S. Mosallam

Masters Theses

In this thesis we make a detailed investigation of the cohomology rings of the cofibers Cβ of Moore spaces of dimension 2 by computing the cup products in cofibers and to do so we prove that the Hopf invariant in case of Moore spaces in the zero and nonzero homomorphism case is a homomorphism. We have shown when is 𝓍r,k a Co-H-Map. We calculated the homologies and cohomologies of Moore spaces of dimension 2 and of the cofibers Cβ where β=𝓍r,k. We used Lusternik-Schnirelmann category to determine the complexity of C …


Per- And Polyfluorinated Alkyl Substances (Pfas) Cycling Within Michigan: Connections Between Contaminated Sites, Landfills, And Wastewater Treatment Plants, Ross W. Helmer Aug 2021

Per- And Polyfluorinated Alkyl Substances (Pfas) Cycling Within Michigan: Connections Between Contaminated Sites, Landfills, And Wastewater Treatment Plants, Ross W. Helmer

Masters Theses

The disposal and treatment of Per- and Polyfluorinated Alkyl Substances (PFAS) contaminated solid and liquid wastes, and associated cycling within the natural and engineered environment is a complex topic. PFAS data on contaminated sites, landfill leachates, the influent, effluent, and biosolids from wastewater treatment plants (WWTPs) within Michigan were compiled from publicly available and private sources. Most of the datasets are based on a 28-analyte suite generated using a modified form of the US EPA 537 analytical method, with a subset of data from the 18-analyte ASTM D7979-19 method. Approximately 70% of the 171 contaminated sites in Michigan have maximum …


Development Of High Throughput Assays For Identification And Evaluation Of Small Molecule Inhibitors Of Microrna-31 Expression, Jackline A. Onyango May 2021

Development Of High Throughput Assays For Identification And Evaluation Of Small Molecule Inhibitors Of Microrna-31 Expression, Jackline A. Onyango

Masters Theses

Dysregulated expression of miRNAs has been linked to numerous cancers. On the other hand, miRNAs are potential drug targets due to the ability of their precursor molecules to fold into ligand binding structures. Small-molecule modulators of miRNAs offers opportunity for the development of new therapeutic agents and tools to further probe the mechanisms of miRNA functions. To facilitate the identification of miRNA modulators, the appropriate screening systems are needed, which would be adaptable for high-throughput applications, and allow for quantitative measurements. In this text, we present a molecular beacon-based assay to identify molecules that inhibit miRNA-31 processing by Dicer and …


Using Low-Flow Sampling Data To Estimate Hydraulic Conductivity In Aquifers, Joy Kiefer May 2021

Using Low-Flow Sampling Data To Estimate Hydraulic Conductivity In Aquifers, Joy Kiefer

Masters Theses

Hydrogeologists sample wells to test aquifer water quality and use slug tests to estimate aquifer permeability. Robbins et al. (2009) proposed a more efficient way to obtain the goals of the two tests—the use of low-flow sampling and the use of the resulting flow rate and drawdown data to estimate aquifer hydraulic conductivity (K). The Robbins et al. method calculates K by using the slope of the best fit line from the graph of flow rate vs. drawdown for all low-flow pumping data collected at a well. When the method was applied to low-flow data from four Kalamazoo, MI, it …


Towards Development Of A Remote Charting System For Connected Healthcare, Alex Bodurka Dec 2020

Towards Development Of A Remote Charting System For Connected Healthcare, Alex Bodurka

Masters Theses

Health Care Providers play a crucial role in a patients well-being. While their primary role is to treat the patient, it is also vital to ensure that they can spend adequate time with the patient to create a unique treatment plan and build a personal relationship with their patients to help them feel comfortable during their treatment. Health Care Providers are frequently required to manually record patient data to track their healthcare progress during their hospital stay. However, with hospitals continuously trying to optimize their workflows, this crucial one-on-one time with the patient is often not practical.

As a solution, …


Agricultural Irrigation Induced Evaporation In A Temperate Study Area: A Stable Isotope Approach, Lincoln Grevengoed Dec 2020

Agricultural Irrigation Induced Evaporation In A Temperate Study Area: A Stable Isotope Approach, Lincoln Grevengoed

Masters Theses

In regions where groundwater is used for irrigation, significant water losses take place due to evaporation. Previous studies demonstrated the utility of stable oxygen and hydrogen isotopes in estimating evaporative water loss experienced during return flow back to an aquifer. Unlike arid regions where the other studies took place, this study examined the region around Kalamazoo, Michigan, the United States, which experiences a more temperate climate. Irrigation in the Kalamazoo area primarily uses center-pivot systems supplied by wells, unlike flood irrigation in previous study areas. Water samples were taken periodically from wells close to center-pivot irrigation systems. Water losses due …


A Framework To Support Automatic Certification For Self-Adaptive Systems, Ioannis Nearchou Aug 2020

A Framework To Support Automatic Certification For Self-Adaptive Systems, Ioannis Nearchou

Masters Theses

Presently, cyber-physical systems are increasingly being integrated into societies, from the economic sector to the nuclear energy sector. Cyber-physical systems are systems that combine physical, digital, human, and other components, which operate through physical means and software. When system errors occur, the consequences of malfunction could negatively impact human life. Academic studies have relied on the MAPE-K feedback loop model to develop various system components to satisfy the self-adaptive features, such that violation of the safety requirements can be minimized. Assurance of system requirement satisfaction is argued through an industrial standard form, called an assurance case, which is usually applied …


Assessing The Robustness And Versatility Of Nanojars For Anion Binding, Mia Lily Ann Jawor Aug 2020

Assessing The Robustness And Versatility Of Nanojars For Anion Binding, Mia Lily Ann Jawor

Masters Theses

Supramolecular chemistry is a field in chemistry that focuses on intermolecular bonds in a “host-guest complex” or supramolecular assemblies. Nanojars are supramolecular assemblies of the formula [anion⊂{Cu(μ-OH)(μ-pz)}n] (n = 27‒33) which incarcerate kosmotropic anions, such as carbonate (CO32‒), sulfate (SO42‒) and hydrogen phosphate (HPO42‒). Nanojars consist of three [Cu(μ-OH)(μ-pz)]x (x = 6‒14, except 11) rings that are assembled similarly to Matryoshka dolls, where the top and bottom rings act as guests for the central ring. The larger central ring is bound to the two smaller rings by multiple …


Analysis Of Interdunal Wetlands And Ecosystem Dynamics Using Uas And Obia In Ludington State Park, Michigan, Claire Gilbert Aug 2020

Analysis Of Interdunal Wetlands And Ecosystem Dynamics Using Uas And Obia In Ludington State Park, Michigan, Claire Gilbert

Masters Theses

The Great Lakes sand dunes are the world's largest freshwater dune complex. There is a functional relationship between coastal wetlands and freshwater sand dune, referred to as interdunal wetlands. Interdunal wetland systems are highly dynamic and change dramatically seasonally and annually. Using geographic information systems (GIS) and unoccupied aerial systems (UAS), this thesis project is focused on understanding the spatial distribution of sparse and dense vegetation, and abiotic influence such as distance to coast, slope, and aspect influence interdunal wetland stability within a Great Lakes shoreline dune system. Object-based image analysis (OBIA) classification results extracted meaningful vegetation densities of growth …


Using Historical Maps For Contaminated Site Identification And Prediction, And Environmental Justice Implications: A Case Study In Grand Rapids, Michigan, Dana Heusinkveld Jun 2020

Using Historical Maps For Contaminated Site Identification And Prediction, And Environmental Justice Implications: A Case Study In Grand Rapids, Michigan, Dana Heusinkveld

Masters Theses

As the production of synthetic chemicals has grown in the past centuries to increase production, lower costs, and generally make our lives more convenient, detecting and understanding the environmental impacts of these compounds has lagged significantly behind their mass production and wide-spread use. To combat this trend, sources of these contaminants, especially those that have been removed from the landscape, need to be quickly identified to make mitigation and remediation efforts more effective. In this study, historical Sanborn maps are used to extract and digitize historical site/land use in Grand Rapids during the early 1900s through the practical application of …


An Analysis Of Factors Influencing Chemistry Students’ Choice Of Major And Career, Jennifer Marie Ribble Apr 2020

An Analysis Of Factors Influencing Chemistry Students’ Choice Of Major And Career, Jennifer Marie Ribble

Masters Theses

In recent years there has been a push to increase the number of STEM graduates in the United States in order for the nation to retain its position as a global leader in the sciences. If educators are to address recruitment and attrition issues in STEM fields it is important to understand student perspectives related to choosing both a major and a career in chemistry. The present study explores the decision-making process students utilize to choose chemistry as a major and as a career, their perception of what careers are available to someone with a degree in chemistry and what …


Field And Numerical Evaluation Of Nitrogen Transport From Septic Systems In Surfical Aquifer Systems To Charlotte Harbor, Florida, Tanten T. Buszka Apr 2020

Field And Numerical Evaluation Of Nitrogen Transport From Septic Systems In Surfical Aquifer Systems To Charlotte Harbor, Florida, Tanten T. Buszka

Masters Theses

Shallow water tables in coastal surficial aquifers limit effective treatment of septic effluent which can result in excess nutrient loading into nearby surface water bodies. Approximately 45,000 septic systems in Charlotte County, Florida transmit effluent into an under studied surficial aquifer and contribute to harmful algal blooms and outbreaks of E. coli. An undeveloped field site was characterized using standard hydrogeologic methods, including a one-year duration natural gradient tracer test, to obtain representative lithology of the sandy surficial aquifer and estimates of groundwater velocity, flow directions, effective porosity and dispersion. These data were used to support the development of a …


Distribution And Variability In Sulfur Isotopes Within Paleoproterozoic Metasedimentary Strata Of The Michigamme Formation, Upper Peninsula, Michigan, Beau J. Haag Apr 2020

Distribution And Variability In Sulfur Isotopes Within Paleoproterozoic Metasedimentary Strata Of The Michigamme Formation, Upper Peninsula, Michigan, Beau J. Haag

Masters Theses

In the Upper Peninsula of Michigan, the Paleoproterozoic Michigamme Formation is composed of a thick package of metasedimentary rocks derived from foreland basin sediments which were deposited during the 1.8Ga Penokean Orogeny. These rocks contain significant, but variable amounts of texturally distinct sulfide minerals such as pyrrhotite and pyrite. We report a systematic relationship between δ34S values from sulfide mineral occurrences, and their stratigraphic locations regardless of texture and mineral composition. We suggest the sulfide minerals within the Michigamme Formation have inherited δ34S values from early sedimentarydiagenetic sulfides, therefore preserving primary isotopic signatures. The observed stratigraphic …


An Analysis Of Large Displacement Pneumatic Slug Tests For The Characterization Of Aquifer Parameters – Guidelines For An Alternative Field Procedure, Madison E. Wayt Apr 2020

An Analysis Of Large Displacement Pneumatic Slug Tests For The Characterization Of Aquifer Parameters – Guidelines For An Alternative Field Procedure, Madison E. Wayt

Masters Theses

Variations in hydraulic conductivity (K) between larger scale aquifer tests and smaller scale slug tests, and within individual aquifer tests, have been linked to method bias and aquifer heterogeneity. The impacts of varying slug sizes on K, which represents K dependence on a smaller scale, is not as well understood. To examine the relationship between K and slug size, a series of slug tests with a range of initial displacements were performed in three intermediate to high K, unconfined aquifers encompassing homogeneous, mildly heterogeneous, and moderate to highly heterogeneous conditions. Slug test estimated K values at Asylum Lake are compared …


Evaluating The Effects Of Sodium, Potassium, Magnesium, And Calcium Concentrations On Dolomite Stoichiometry, Cation Ordering, And Reaction Rate, Hanna F. Cohen Dec 2019

Evaluating The Effects Of Sodium, Potassium, Magnesium, And Calcium Concentrations On Dolomite Stoichiometry, Cation Ordering, And Reaction Rate, Hanna F. Cohen

Masters Theses

Numerous environmental factors affect dolomitization. Shallow peritidal and restricted marine environments, for example, are often associated with more abundant and more stoichiometric dolomite than deeper marine environments. Higher fluid Mg/Ca ratios resulting from gypsum precipitation are often invoked to explain this observation, even when evidence of evaporites is absent. In this study, high-temperature dolomitization experiments show that the concentrations of major cation concentrations (Na, K, Mg, and Ca) impact dolomite stoichiometry and reaction rate. Nearly 200 batch dolomitization experiments were run whereby 100 mg of natural aragonite ooids were dolomitized at 215°C in ionic solutions. Fluid [NaCl] and [KCl] correlate …


Synthesis And Characterization Of Ion-Implanted Gold Nanoparticles, Nurlathifah Fnu Dec 2019

Synthesis And Characterization Of Ion-Implanted Gold Nanoparticles, Nurlathifah Fnu

Masters Theses

Gold negative ions of 70 keV energy were implanted within the quartz substrates at room temperature at seven different fluences starting from 2 x 1016 particles/cm2 to 8 x 1016 particles/cm2 with the increment of 1 x 1016. Prior to the implantation, Stopping and Range of Ions in Matter (SRIM) calculations were carried to obtain the Bragg peak below the surface of quartz. Rutherford Backscattering Spectrometry (RBS) was carried out using 2.0 MeV He++ ions to measure depth and implanted fluence of gold, and learn how they varied with fluence. Backscattered He particles …