Environmental Chemistry Commons^™

Lc-Ms Discriminates Between Effects Of Sulfur Nanoparticles Vs Molybdenum Disulfide Nanoparticles On Lettuce (Lactuca Sativa), Mary Fakunle

Graduate Theses/Dissertations

Nanotechnology is gaining attention in agriculture, majorly due to their potential benefits in farming practices. Sulfur and molybdenum disulfide nanoparticles are reported to enhance plant growth, protection, and nutrient delivery. However, there is a need to understand how nano-fertilizers affect the metabolites and nutritional benefits of plants. Here, lettuce was cultivated under greenhouse in one of three treatments: control, 50 ppm S NPs, and 20 ppm MoS2 NPs. A method was developed on Liquid Chromatography – Mass Spectrometry (LC-MS) instrument to quantify the concentration of amino acids and antioxidants in the harvested lettuce plants. Inductively Coupled Plasma – Mass Spectrometry …

Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones

Graduate Theses/Dissertations

Karst landscapes are abundant in Missouri, with features such as caves, springs, and sinkholes that form through the dissolution of limestone. Leith Creek is a small stream in Polk County, Missouri fed by two springs and the shallow unconfined Springfield Plateau aquifer, a highly karstified aquifer which is made up of limestone and minor interbedded shale-mudstone units. To determine if Leith Creek is gaining or losing, stream flow, water chemistry and temperature sensors were monitored. Stream flow results required multiple visits to take measurements while temperature sensors required two visits, one to install the dataloggers and another to remove the …

Cloud Condensation Nuclei Activity Of Fresh And Aged Phenolic Acid Aerosol Particles, Emily A. Nortmann

Honors Undergraduate Theses

In recent years, the incidence of wildfires has considerably increased, with fire seasons starting earlier and ending later than usual due to changes in snowpack, precipitation, and temperature, which are attributed in part to climate change. Wildfires are responsible for the emission of a variety of gases and organic aerosol particles in the atmosphere with profound impacts on air quality, visibility, and human health. The aerosol particles produced by wildfires can contribute to climate change by scattering or absorbing solar radiation, affecting the radiative balance of the planet through cooling or warming effects, or by acting as cloud condensation nuclei …

High Throughput, Solid Sample Analysis With Cone-Based Mass Spectrometric Ionization Sources, Emily J. Wiggins

Theses and Dissertations

The widespread presence of environmental and consumer-product contaminants (e.g. trace metals, opium alkaloids) has underscored the need for rapid, reliable, and high-throughput analytical techniques that are capable of handling complex solid samples. While traditional mass spectrometric (MS) methods tend to have high sensitivity and accuracy, they often require labor-intensive and time-consuming sample preparation steps that limit throughput and field applicability. This thesis investigates the use of 3D-Printed Cone Spray Ionization-Mass Spectrometry (3D-PCSI-MS) as an ambient ionization technique for the direct screening of contaminants from solid matrices, eliminating the need for traditional sample preparation and allowing for real-time analysis.

In …

Cfd Analysis Of Hydrodynamic Cavitation Through An Orifice: Influence Of Different Inlet Pressures And Number Of Orifice Holes, Lemthong Chanphavong, Vongsavanh Chanthaboune, Keophousone Phonhalath

ASEAN Journal on Science and Technology for Development

Hydrodynamic cavitation (HC) is considered an energy-efficient process with high potential for utilization in many chemical processes. This study presents a computational fluid dynamics (CFD) analysis of cavitating flow through an orifice with a constant flow area. The Reynolds-Averaged Navier-Stokes (RANS) equations, coupled with turbulence and cavitation models, are employed to capture the complex flow behaviors. The effects of inlet pressures and number of orifice-holes on cavitation behavior are investigated. Result of the numerical simulation is validated with the existing experimental data from the literature. The CFD study revealed that cavitation initiates just behind the inlet edge of the orifice …

Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …

Targeted Mitigation Strategies To Reduce Secondary Emissions In Co2 Capture Systems, Keemia Abad

Theses and Dissertations--Chemistry

Global CO₂ emissions from industrial, power generation and transportation sources has led to the call for increased implementation of carbon capture strategies. The most developed of these is point source carbon capture, which refers to the process of capturing CO₂ directly from large (point) source emitters, before the CO₂ is released into the atmosphere. The challenge becomes separating CO₂ from the other components of the emitted gas, mainly nitrogen. These CO₂ capture processes typically involve the use of aqueous solutions of amines to absorb (capture) CO₂ from the gas stream, where the CO₂ and the …

A Biogeochemical Perspective On Acidification And Buffering Capacity In The Piscataqua Estuary, Sanjana Varanasi

Master's Theses and Capstones

Coastal acidification is influenced not only by rising atmospheric CO2 and river-ocean mixing, but also by metabolic processes that alter seawater carbonate chemistry and buffering capacity. This study examines how sedimentary biogeochemical processes contribute to carbonate system variability in the Piscataqua Estuary, a tidally dynamic channel connecting Great Bay to the Gulf of Maine. The biogeochemical processes considered include sedimentary aerobic respiration, denitrification, sulfate reduction, and carbonate dissolution or precipitation. Two incubation experiments were conducted in September and October of 2024 at the University of New Hampshire’s Coastal Marine Laboratory (CML) to quantify changes in pH, dissolved inorganic carbon (DIC), …

Quantifying Inositol Phosphate Dephosphorylation To Understand The Role Of Recalcitrant Organic Phosphorus Forms On Harmful Algal Blooms In Freshwater Systems, Iffat Tasnim

College of Graduate Studies: Theses & Dissertations

Organophosphorus such as phytic acid, a surrogate species of inositol phosphate (IP), may serve as a source for orthophosphate (OP) in freshwater. In absence of OP, competent aquatic microorganisms upregulate the production of specialized enzymes to obtain growth-sustaining OP from organic phosphorus (org-P) forms. The contribution of recalcitrant org-P to the OP pool has been overlooked due to the lack of capable tools to measure OP production from org-P accurately. The objective of this study was to quantify OP production from phytic acid (a surrogate form of recalcitrant org-P) to assess the contribution of recalcitrant org-P forms to the total …

Catalytic Innovation For Sustainable Styrene Production: Green Chemistry Strategies Utilizing Octahedral Ruthenium (Ii) Complexes Supported By A Single Bipyridine Ligand, Kennedy G. Musso, Brandon Quillian, Clifford Padgett, Jose Jimenez

College of Graduate Studies: Theses & Dissertations

This study investigates: 1) the synthesis and reactivity of the mono- substituted systems, [κ²-(t-bipy)Ru(NCMe)2(Ph)(PR3)][BArF'] supported by different ancillary ligands PR3 = (P(OCH3)3 and P(CH3)3) and a single bidentate ligand, 4,4′-di-tert-butyl-2,2′-bipyridine (t-bipy), and 2) UV/heat formation of di-PR3 and tri-PR3 systems supported by a single bidentate ligand to better understand the mechanism of styrene production. Utilizing [(η6-p-cymene)RuI(µ-I)]2 (1), the complexes (η6-p-cymene)RuI2(P(OCH3)3) (2) and (η6-p-cymene)RuI2(P(CH3)3) (3) were synthesized and phenylated to produce (η6-p-cymene)RuI(Ph)(PR3) (6; PR3 = P(OCH3)3 and 7; PR3 = P(CH3)3). Complex 4, (η6-p-cymene)RuCl2(P(CH3)3), was also synthesized and phenylated to produce (η6-p-cymene)RuClPh(P(CH3)3) (5) to understand the impact of chloride versus iodine …

Extreme Value Theory Analysis Of High Emitter Trends Across Four Us Cities From 1995 To 2021, M. Matti Maricq, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

Extreme value theory provides a direct means to characterize the distribution of high emitters within a vehicle fleet and calculate statistical confidence intervals for comparisons. Defining a “high emitter” as the maximum emitter in a random sample of N vehicles implies in the limit of large N that high emitters follow an extreme value distribution, comprised of three distinct domains. The analysis of over twenty years of roadside remote sensing emissions measurements in Chicago, Denver, Los Angeles and Tulsa reveals clear differences between gasoline vehicle high emitter distributions across pollutants (hydrocarbons (HC), carbon monoxide (CO) and nitric oxide (NO)), but …

A Potentially Fruitful Path Toward A Cleaner And Safer Environment: Mxenes Uses In Environmental Remediation, Ali Mohammad Amani, Milad Abbasi, Atena Najdian, Farzaneh Mohamadpour, Seyed Reza Kasaee, Hesam Kamyab, Shreeshivadasan Chelliapan, Hanieh Ardeshiri, Lobat Tayebi, Ehsan Vafa, Sarah Mosleh-Shirazi, Alireza Jahanbin, Saravanan Rajendran, Daniel Simancas-Racines

Electrical & Computer Engineering Faculty Publications

The rapid industrialization of the world has resulted in severe environmental pollution, necessitating the development of new materials such as pollution remediation. Two-dimensional (2D) MXenes have emerged as a promising family of materials due to their unique physicochemical properties, making them ideal for environmental remediation. The article sheds light on the new opportunities of MXenes in the removal of organic and inorganic contaminants, including organic dyes, pharmaceuticals, heavy metals, radionuclides, and gas pollutants. MXenes also show excellent performance in photocatalytic degradation, adsorption, and microbial inactivation with environmental safety. Moreover, their application in recovering valuable elements from waste streams is also …

New Psychoactive Substances Detected In Wastewater Samples Collected Along The Interstate Highway Rest Areas In Kentucky, Durga Prasad Kodati

Murray State Theses and Dissertations

The rapid emergence and proliferation of new psychoactive substances (NPS) pose significant challenges to public health and law enforcement. The potential for abuse and toxicity of these substances, which are intended to mimic the effects of controlled drugs, has been raising concerns as these compounds are designed to evade being regulated. There are traditional methods of tracking NPS, such as seizures and forensic toxicology, but they are delayed and seldom effective because these substances continue to evolve rapidly. Wastewater-based epidemiology (WBE) has emerged as a promising tool for real-time surveillance of drug consumption. The primary objective of this research was …

Potential Health Risks From Trace Elements In Four Commercially Important Fish Species From The Gulf Of Alaska And Bering Sea Excel Data Sheet, Miranda Brohman, Dimtirios Giarikos, Amy Hirons

SECLER Data

Alaskan waters support a diverse array of fish species that are critical to apex predators and substantial commercial fisheries. Archived white lateral muscle tissue for capelin, herring, walleye pollock, and Pacific cod, from 1993 to 1996 were analyzed for 15 trace elements using induced coupled plasma mass spectrometry. This analysis serves as a proxy for assessing trace element concentrations in the Gulf of Alaska and Bering Sea. The highest concentrations of eight of the 15 elements (cadmium, chromium, cobalt, iron, manganese, selenium, vanadium, and zinc) were found in fish from the central Gulf of Alaska, while capelin showed the …

Recyclable Composites Prepared From Animal Coproducts And Industrial Waste Sulfur, Perla Y. Sauceda-Oloño

All Dissertations

Pursuing sustainable and environmentally friendly materials has become a significant objective in materials science, particularly flame retardants and construction materials. This dissertation explores the development and evaluation of novel composites and high sulfur-content materials (HSMs) as potential alternatives to conventional, environmentally harmful materials.

Chapter one reviews recent advancements in environmentally benign flame-retardant additives, highlighting the potential of bio-derived phenols, polysaccharide derivatives, and greener phosphorus sources. The review discusses how green additives can enhance the flame retardancy, thermal stability, and smoke suppression properties of various polymers while addressing the challenges and future directions in the field.

Chapter two investigates the production …

Co2 Capture Utilizing Novel Deep Eutectic Solvents: Modeling, Process Simulation, And Cost Analysis, Nazneen Aspi Kolah

Masters Theses

One of the most pressing global issues that humans face is climate change caused by anthropogenic greenhouse gas emissions, especially carbon dioxide (CO2). Conventional solvents utilized for CO₂ capture, such as amines, are widely used in industrial applications due to their high CO2 absorption capacity. However, deep eutectic solvents (DES) have attracted a lot of academic attention recently due to their biodegradability and low energy for regeneration.

This research serves as a foundational proof-of-concept for using DESs in industrial gas separation processes. Five DES are evaluated for CO2 removal from flue gases. Aspen Plus is utilized to simulate the performance …

Bioremediation Of Effluent Water In A Coal Ash Disposal Area: Optimizing Microbial Sulfate Reduction, Ryka Shea

Electronic Theses and Dissertations

Coal combustion residues (CCR) pose a serious environmental threat, even long after they are disposed of in specialized landfills, due to their complex composition and potential for leaching into waterways. This study focuses on the issue of elevated sulfate concentrations at the Martin Lake Steam Electric Station (MLSES) A-I Disposal Area in Panola County, Texas, where CCR are disposed of in a permanent landfill. Currently, this site is exceeding its regulatory limit of sulfate concentrations in its effluent and is in need of a cost-effective and sustainable solution to this problem. This research utilized benchtop experiments to investigate sulfate reducing …

Potential Cell Preservation In Mars-Relevant Clay Minerals, Hanford Gerille Gonzales, Leena M. Cycil, Elisabeth Hausrath

Undergraduate Research Symposium Posters

This study investigates the potential of Fe-nontronite, a clay mineral found on Mars, to preserve biological cells and retain biosignatures such as trace metals. The research explores the preservation potential of nontronite by reacting it with cells under the following conditions: 1) reacting cells with nontronite precursors at low temperature and 2) reacting cells with the already synthesized nontronite made at high temperature. Microbial species Shewanella oneidensis and Geobacter metallireducens, known for their relevance to iron-rich environments, were introduced in intact and lysed forms to assess their interactions with each condition of nontronite. Preliminary results from scanning electron microscopy (SEM) …

Carbon Restoration Potential On Global Land Under Water Resource Constraints, Shouzhang Peng, César Terrer, Benjamin Smith, Philippe Ciais, Qinggong Han, Jialan Nan, Joshua B. Fisher, Liang Chen, Lei Deng, Kailiang Yu

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ecosystem restoration is a critical nature-based solution to mitigate climate change. However, the carbon sequestration potential of restoration, defined as the maximum achievable carbon storage, has likely been overestimated because previous studies have not adequately accounted for the competition between ecosystem water demands for maximizing carbon sequestration and human water needs. Here we used a comprehensive process-based model combined with extensive land-use data and evaporation recycling accounting for land–atmosphere feedback to estimate the water requirements associated with ecosystem restoration. We found that achieving the carbon sequestration potential of restoration would significantly reduce global water availability per capita by 26%, posing …

Local Hydroclimate Alters Interpretation Of Speleothem Δ18o Records, E. W. Patterson, V. Skiba, A. Wolf, M. L. Griffiths, D. Mcgee, T. N. Bùi, M. X. Trần, T. H. Đinh, Q. Đỗ-Trọng, Gregory R. Goldsmith, V. Ersek, K. R. Johnson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Oxygen isotopes (δ¹⁸O) are the most commonly utilized speleothem proxy and have provided many foundational records of paleoclimate. Thus, understanding processes affecting speleothem δ¹⁸O is crucial. Yet, prior calcite precipitation (PCP), a process driven by local hydrology, is a widely ignored control of speleothem δ¹⁸O. Here we investigate the effects of PCP on a stalagmite δ¹⁸O record from central Vietnam, spanning 45 – 4 ka. We employ a geochemical model that utilizes speleothem Mg/Ca and cave monitoring data to correct the δ¹⁸O record for PCP effects. The resulting record …