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Full-Text Articles in Chemistry

Climate And Environmental Controls On Forest Soil Organic Matter Cycling, Genevieve Goebel Jan 2026

Climate And Environmental Controls On Forest Soil Organic Matter Cycling, Genevieve Goebel

Dartmouth College Ph.D Dissertations

Climate change factors act on the soil environment in complex ways, known to disturb soil organic carbon (C). Rising global temperatures and alterations to regional precipitation and nitrogen deposition regimes may contribute to the intensification of global change by accelerating the rate of biological decomposition and CO2 efflux to the atmosphere. The magnitude and endurance of the disturbance to soil organic C across landscapes and throughout time that climate change factors may pose to soil C cycling are not comprehensively understood. These knowledge gaps in our field make it challenging to anticipate how soil environments and the vast ecosystems that …


A Geospatial Assessment Of Groundwater Salinization In A Multi-Aquifer System: Durango, Mexico, Juan Lopez-Sierra Jan 2026

A Geospatial Assessment Of Groundwater Salinization In A Multi-Aquifer System: Durango, Mexico, Juan Lopez-Sierra

Graduate Theses/Dissertations

Groundwater salinization poses a critical environmental concern for water resource sustainability in arid and semi-arid regions. This study evaluates spatial and temporal patterns of groundwater salinity across the state of Durango, Mexico, using total dissolved solids (TDS), sodium adsorption ratio (SAR), as salinity indicators and nitrate-nitrogen (NO₃–N) as an anthropogenic indicator. Groundwater quality data were obtained from (CONAGUA), a Mexican water agency. To assess salinity variations with respect to time, while minimizing interannual sampling bias, two multi-year sampling periods were selected: 2012-2013, and 2020-2021. Final datasets consisted of 122 wells for 2012–2013 and 131 wells for 2020–2021. The wells were …


Assessing Dissolved Organic Matter Sources And Dynamics In Urban Stormwater: Implications For Greenhouse Gases, Harper W. Schmalz Jan 2026

Assessing Dissolved Organic Matter Sources And Dynamics In Urban Stormwater: Implications For Greenhouse Gases, Harper W. Schmalz

Theses and Dissertations (Comprehensive)

Stormwater management ponds (SWMPs) are important aspects of land-use planning and increasingly recognized as active sites of biogeochemical processing that influence carbon cycling; however, little research has investigated the controls on dissolved organic and dissolved inorganic carbon (DOC and DIC) within these systems. This thesis examined the processing and transformations of dissolved carbon between three compartments to support the development of a greenhouse gas (GHG) box-model for urban stormwater ponds, including SWMP sediment, surface water, and vegetation. The objective of this thesis was to assess the biogeochemical processes that govern the rate and transformation of DOC and DIC between these …


Analysis Of Δ¹¹B As A Seawater Ph Proxy: Comparing Ocean Circulation Inverse Model Output With Marine Calcifier Geochemistry, Jesse I. Dong Jan 2026

Analysis Of Δ¹¹B As A Seawater Ph Proxy: Comparing Ocean Circulation Inverse Model Output With Marine Calcifier Geochemistry, Jesse I. Dong

CMC Senior Theses

Increasing anthropogenic carbon flux into the oceans decreases seawater pH, alters dissolved inorganic carbon speciation, and reduces biogenic calcification. The marine calcifiers— specifically corals and coralline algae—incorporate elements from surrounding seawater into their carbonate structures, which preserve past records of ocean carbon chemistry. In particular, boron in biogenic carbonate is a potentially valuable proxy for historical ocean pH across human timescales. Within seawater, boron primarily exists as boric acid B(OH)3 and borate ions B(OH)4 - , where higher pH favors the formation of borate ions. Borate ions preferentially incorporate the heavier ¹¹B isotope over 10B. On the other hand, if …


Feasibility Of Upcycling Spent Lithium-Ion Battery To Carbon Dioxide Capture Adsorbent, Chimezie Frank Onwudinjo Jan 2026

Feasibility Of Upcycling Spent Lithium-Ion Battery To Carbon Dioxide Capture Adsorbent, Chimezie Frank Onwudinjo

Master’s Theses

This study investigates the feasibility of repurposing spent lithium-ion battery (SLIB) to lithium orthosilicate (Li4SiO4), a high temperature carbon dioxide sorbent. Two synthesis pathways including conventional acid-leaching method (Scenario 1) and a pyrolysis-based route (Scenario 2) were explored. Additionally, techno-economic analysis (TEA) and lifecycle assessment (LCA) of the two processes were also performed. Different analytical characterization techniques were performed to understand the material properties of Li4SiO4 including surface area, crystallinity, morphology and thermal stability. CO2 capture performance of the synthesized Li4SiO4 was tested in a thermogravimetric analyzer (TGA) using …


Novel Methods For Environmental Fluoride Measurement, Cable Warren Jan 2026

Novel Methods For Environmental Fluoride Measurement, Cable Warren

Chemistry & Biochemistry Dissertations

Fluoride analysis has been an important focus of analytical analysis for many years and will continue to be so going forward. Today, fluorinated compounds, specifically per/polyfluoroalkyl substances (PFAS), better known as “forever chemicals” have captured the moment and are the subject of vast research and regulation. Under this context, I have researched new methods of fluoride separation and concentration in complex media as well as a novel method of PFAS destruction and total organic fluorine analysis for screening of PFAS in aqueous samples. Through research and work on micro-scale detection methods, an understanding of the state of the art and …


Marine Sentinels Of The Past: Holocene Trace Element Records From North Pacific Pinnipeds, Aidan M. Pflieger Jan 2026

Marine Sentinels Of The Past: Holocene Trace Element Records From North Pacific Pinnipeds, Aidan M. Pflieger

Honors Theses

Since the Last Glacial Maximum (20,000 years ago), the North Pacific has remained geologically dynamic and biologically diverse. Natural fluctuations in island arc volcanism and climate likely continue to influence the inputs of trace elements (TEs) to the Aleutian Island Archipelago. Bioaccumulation of these TEs in the region’s marine food webs provides a proxy for long-term environmental variability. In this study, 95 tephra-preserved pinniped bone samples from temporally identified archeological Aleut midden sites on Unalaska Island (5500-200 BP; BP=years before present, c. 1950), were analyzed for 20 TEs using inductively coupled plasma mass spectrometry (ICP-MS). Elemental concentrations were compared temporally …


Pipeline Corrosion And Relevant Microbial Influence, Renee E. Bamberger Jan 2026

Pipeline Corrosion And Relevant Microbial Influence, Renee E. Bamberger

Williams Honors College, Honors Research Projects

This study investigated the role of microbial activity and oxygen availability in the corrosion of carbon steel pipelines with a focus on microbially influenced corrosion (MIC). Sediment collected from Old Woman Creek, Ohio, was used to simulate natural soil conditions, and carbon steel coupons were incubated under four treatments: nonsterile oxic, nonsterile anoxic, autoclaved oxic, and autoclaved anoxic over 85 days. Corrosion was assessed through mass loss measurements and the analysis of pH, sulfate, chloride, and dissolved iron concentrations. The greatest mass loss was observed in autoclaved oxic conditions, contrary to the initial hypothesis that microbial activity would greatly enhance …


De Novo Protein Binding To Zinc Oxide Through Biomineralization Pathways, Jean-Mark A. Francis Jan 2026

De Novo Protein Binding To Zinc Oxide Through Biomineralization Pathways, Jean-Mark A. Francis

Theses and Dissertations

De novo proteins are structurally distinct from proteins found in nature and thus capable of having their amino acid sequence modified to accomplish tasks such as increasing protein-nanoparticle binding without unfolding or decomposing. Zinc Oxide nanoparticles are functionally distinct from their bulk counterparts and are widely used as semiconductors in a variety of fields such as medicine and agriculture. With demand for these nanoparticles increasing, environmentally sustainable methods of Zinc Oxide nanoparticle synthesis are being investigated as an eco-friendly alternative to currently utilized but environmentally hazardous chemical and physical techniques. This research investigates the binding characteristics between Zinc Oxide nanoparticles …


Nanostructured Cathode Catalysts For Aem Electrolysis: From Catalyst Design To Degradation And Hydrogen Dynamics, Yamini Kumaran Jan 2026

Nanostructured Cathode Catalysts For Aem Electrolysis: From Catalyst Design To Degradation And Hydrogen Dynamics, Yamini Kumaran

Electronic Theses & Dissertations (2024 - present)

Anion exchange membrane water electrolysis (AEMWE) presents a promising pathway toward cost-effective and sustainable hydrogen production by integrating the chemical robustness of alkaline systems with the compact, zero-gap design of proton exchange membrane electrolyzers. However, the widespread implementation of AEMWE is limited by the availability of highly active and durable platinum-group-metal (PGM)-free catalysts and by an incomplete understanding of their degradation behavior under realistic operating conditions.

This dissertation focuses on the development, characterization, and mechanistic investigation of nanostructured MoNi4–MoO2-based electrodes for efficient and stable hydrogen generation under alkaline and membrane-integrated environments. MoNi4–MoO2 nanorods …


Swimming In Uncertainty: Filling Data Gaps And Providing An Educational Platform For Beach Water Quality At Tybee Island, Georgia, Lukas Roberson Jan 2026

Swimming In Uncertainty: Filling Data Gaps And Providing An Educational Platform For Beach Water Quality At Tybee Island, Georgia, Lukas Roberson

College of Graduate Studies: Theses & Dissertations

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Swimming in beaches water contaminated with high levels of bacteria can make you sick. Current monitoring at the public beaches on Tybee Island consists of weekly monitoring and enumeration of fecal indicator bacteria that takes 24 hours for results. If the number of bacteria exceed regulatory limits, a public health advisory is issued, and affected waters are retested until …


Application Of Organic Geochemistry To The Characterization Of Hydrochar And Biochar: Insights Into Composition And Optimization, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Rubén Forján, José Luis Gallego Jan 2026

Application Of Organic Geochemistry To The Characterization Of Hydrochar And Biochar: Insights Into Composition And Optimization, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Rubén Forján, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Hydrothermal carbonization has garnered significant attention in recent studies due to potential applications of the hydrochar produced, which overlap with those of torrefied biochar, including soil improvement, carbon sequestration, and energy production. However, unlike the relatively uniform properties of biochar, hydrochar characteristics can vary greatly depending on the feedstock used. Advanced characterization techniques are essential to better understand these materials and enhance their practical applications. Research on hydrochar requires a multi-faceted approach, including molecular-level studies, to optimize production processes and identify specific applications.

In this regard, analytical methods commonly used in organic geochemistry could play a crucial role in deepening …


Bio-Papcz: Corn Starch-Based Composite Bioplastic Reinforced With Pineapple Leaf Fiber (Palf), Zinc Oxide (Zno), And Polyvinyl Alcohol (Pva), Marvin C. Caya, Shervin Austin C. Huang, Jovar Khalel J. Maghari, Ruel M. Levida Dec 2025

Bio-Papcz: Corn Starch-Based Composite Bioplastic Reinforced With Pineapple Leaf Fiber (Palf), Zinc Oxide (Zno), And Polyvinyl Alcohol (Pva), Marvin C. Caya, Shervin Austin C. Huang, Jovar Khalel J. Maghari, Ruel M. Levida

Sinaya: A Philippine Journal for Senior High School Teachers and Students

Plastic pollution poses a serious global threat, as petroleum-based plastics persist for centuries, and their surging production of over 450 million tons overwhelms ecosystems (Ritchie et al., 2023). Using a quantitative experimental research design, the study examined the effects of varying concentrations of cornstarch-based bioplastic reinforced with pineapple leaf fiber (PALF), polyvinyl alcohol (PVA), and zinc oxide (ZnO) on the bioplastic’s tensile strength and soil degradability. Sample C2 (ZnO 3.0 %w/w; PVA 9.0 %w/w) demonstrated the optimal tensile properties with a tensile strength of 0.76 MPa and an elongation at break of 6.40%, which was attributed to the addition of …


Suitability Of Mobile Phase Recycling For Methylxanthine Quantification In Coffee Samples Using Hplc, Kaitlin O’Keeffe, Marcos Mariano, Brian Murphy Dec 2025

Suitability Of Mobile Phase Recycling For Methylxanthine Quantification In Coffee Samples Using Hplc, Kaitlin O’Keeffe, Marcos Mariano, Brian Murphy

SURE Journal: Science Undergraduate Research Experience Journal

Caffeine, theobromine and theophylline fall under a drug class known as methylxanthines. These three compounds are of major interest in the food industry due to their presence in popular foods and beverages such as tea, coffee, and chocolate. As these compounds can cause physical and mental stress at high dosages, their quantification is essential to ensure product safety and quality. Here, we describe an eco-friendly HPLC method developed to quantify the amount of these analytes in coffee samples sourced across the SETU Waterford, Cork Road campus. Using an isocratic mixture of water and methanol, a mobile phase recycling approach was …


Investigating Mariculture-Associated Ecosystem Services Across The Northern Gulf Of Alaska, Josianne Haag Dec 2025

Investigating Mariculture-Associated Ecosystem Services Across The Northern Gulf Of Alaska, Josianne Haag

Oceanography

The rapid expansion of mariculture in Alaska can drive physical and chemical alterations to the marine environment by introducing non-native organisms or artificially increasing the biomass of a native species. Currently, the main mariculture products grown in Alaska include the Pacific oyster (Crassostrea gigas), the Pacific blue mussel (Mytilus trosuslus), and three macroalgae species: ribbon kelp (Alaria marginata), sugar kelp (Saccharina latissima), and bull kelp (Nereocystis luetkeana). This dissertation examines how these species can impact their surrounding environment to better inform management practices for this growing industry. This research characterized the resource use of C. gigas and M. trossulus seasonally …


Terrestrial And Lacustrine Organic Matter Biomolecular Transformations Via Thermal Maturation And Oxidative Degradation, Louis Connor Bondurant Dec 2025

Terrestrial And Lacustrine Organic Matter Biomolecular Transformations Via Thermal Maturation And Oxidative Degradation, Louis Connor Bondurant

Chemistry & Biochemistry Theses & Dissertations

The most abundant source of fossil fuel-forming kerogen on Earth is classified as Type II kerogen, believed to originate from marine biomass. However, a significant amount of lacustrine and terrigenous carbon is transported to the ocean through fluvial discharge. Less than half of the exported organic carbon is observed in coastal regions and the open ocean. There is a great need for an explanation of what is happening to this organic carbon during transport and deposition. Traditionally, the marine organic matter in coastal regions accumulates to eventually be buried and transformed into petroleum over millions of years due to its …


Molecular Design And Engineering Of Luminophores For Aggregation Induced Electrogenerated Chemiluminescence, Jesy Alka Motchaalangaram Dec 2025

Molecular Design And Engineering Of Luminophores For Aggregation Induced Electrogenerated Chemiluminescence, Jesy Alka Motchaalangaram

Dissertations

Most conventional luminophores produce intense emissions in solutions but suffer from weak emissions or quenching when aggregated in poor solvents due to intermolecular interactions, such as π-π stacking. This phenomenon is known as aggregation caused by quenching (ACQ), limits their applications in their solid state. In contrast, aggregation induced emission (AIE) is a phenomenon in which luminophores are weak- or non-emissive in solution but emit intensively in their aggregated or solid states. AIE has enabled significant advancements in various real-world applications and has inspired new areas of research. The combination of AIE with electrogenerated chemiluminescence (ECL) has resulted in a …


Assessment Of Bacteriological Quality And Physico-Chemical Parameters Of Domestic Water Sources In Relation To Human Health Risk In Kigamboni, Tanzania, Joseph A. Mwakosya Oct 2025

Assessment Of Bacteriological Quality And Physico-Chemical Parameters Of Domestic Water Sources In Relation To Human Health Risk In Kigamboni, Tanzania, Joseph A. Mwakosya

Tanzania Journal of Science

Data on bacteriological quality and physico-chemical parameters is crucial for protection and sustainable utilization of water resources. This study determined bacteriological quality and physico-chemical parameters of well and tap water sourcesin relation to human health risk in Kigamboni, Tanzania. Thirty water samples were collected randomly and analyzed using SPSS software. The mean values for well water samples of pH, electrical conductivity (EC), total dissolved solids (TDS), turbidity, Chloride, Sulphate, Nitrate, Phosphate, and Calcium Carbonate were 7.2, 960.27 mg/L, 528.13 mg/L, 1.52 NTU, 288.00 mg/L, 30.13 mg/L, 0.05 mg/L, 0.08 mg/L, and 160.07 mg/L, respectively. The mean values for tap water …


Dramatic Biases In Terrestrial Nitrogen Fixation In Earth System Models Revealed By Natural Isotope Signatures, Maoyuan Fang, Shushi Peng, Philippe Ciais, Daniel S. Goll, Benjamin Z. Houlton, Ying-Ping Wang, Yilong Wang, Pan Liu, Joshua B. Fisher, Pierre Regnier Oct 2025

Dramatic Biases In Terrestrial Nitrogen Fixation In Earth System Models Revealed By Natural Isotope Signatures, Maoyuan Fang, Shushi Peng, Philippe Ciais, Daniel S. Goll, Benjamin Z. Houlton, Ying-Ping Wang, Yilong Wang, Pan Liu, Joshua B. Fisher, Pierre Regnier

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Biological nitrogen fixation (BNF) is the primary input of new reactive nitrogen to natural terrestrial ecosystems. However, this flux is poorly constrained due to its unclear drivers and associated control mechanisms. Here, we extend the existing theory of nitrogen (N) isotope mass balance to estimate BNF rates and then use a Bayesian approach to constrain the BNF rates in natural terrestrial ecosystems by using measurements of natural N-isotope ratios (δ15N) in plants (δP) and soil (δS). Together with pairwise δP and δS measurements from 18 forest sites covering diverse climates and thousands …


Day-Night Shifts In Water-Soluble Ions Of Size-Resolved Aerosols Before And After The Covid-19 Lockdown In A Coastal Megacity: Metro Manila, Philippines, Grace Betito, Paola Angela Bañaga, Rachel A. Braun, Maria Obiminda Cambaliza, Melliza Templonuevo Cruz, Alexander B. Macdonald, James Bernard Simpas, Connor Stahl, Armin Sooroshian Oct 2025

Day-Night Shifts In Water-Soluble Ions Of Size-Resolved Aerosols Before And After The Covid-19 Lockdown In A Coastal Megacity: Metro Manila, Philippines, Grace Betito, Paola Angela Bañaga, Rachel A. Braun, Maria Obiminda Cambaliza, Melliza Templonuevo Cruz, Alexander B. Macdonald, James Bernard Simpas, Connor Stahl, Armin Sooroshian

SOSE Affiliate: Manila Observatory

The COVID-19 pandemic-driven lockdowns offer a unique opportunity to examine how reductions in anthropogenic emissions impacted atmospheric aerosol composition in urban environments. This study investigates the day-night variability of size-resolved water-soluble ions in ambient particulate matter (PM) collected in Metro Manila before (November 2019–February 2020) and after (November 2020–February 2021) lockdown implementation. Using tandem Micro-Orifice Uniform Deposit Impactors (MOUDIs), aerosol samples were collected during daytime (06:00–18:00) and nighttime (18:00–06:00) periods and analyzed for key ionic species (sulfate, ammonium, nitrate, oxalate, sodium, chloride, calcium, and magnesium) via ion chromatography. Submicrometer water-soluble mass declined post-lockdown, particularly during daytime, reflecting suppressed secondary formation …


Mechanistic Distinction Between Oxidative And Chlorination Transformations Of Chloroperoxidase From Caldariomyces Fumago Demonstrated By Dye Decolorization, Norman Paz-Ramirez, Jacob Redwinski, Matthew A. Cranswick, Kyle A. Grice, Kari Stone Oct 2025

Mechanistic Distinction Between Oxidative And Chlorination Transformations Of Chloroperoxidase From Caldariomyces Fumago Demonstrated By Dye Decolorization, Norman Paz-Ramirez, Jacob Redwinski, Matthew A. Cranswick, Kyle A. Grice, Kari Stone

Chemistry Department Faculty Articles

Effluents from the textile industry, particularly those containing synthetic azo dyes, poses a significant environmental threat, necessitating the development of more effective and sustainable pollutant removal methods. Traditional dye removal techniques often fall short in efficiency and environmental impact, prompting the exploration of enzymatic degradation as a promising alternative. This study focuses on chloroperoxidase, a natural biocatalyst recognized for its ability to oxidize synthetic dyes into less harmful products. By exploring the mechanistic distinction between chlorination and oxidative processes, we investigate the enzyme’s specific degradation pathways for azo dyes and the resulting by-products. Utilizing analytical techniques, including liquid chromatography/mass spectrometry …


Unraveling Crop Nitrogen-Water Dynamics With Hyperspectral-Thermal Sensing In Northern Central Valley, California, Shahryar Fazli, Surendra Maharjan, Wenzhao Li, Joshua B. Fisher, Rejoice Thomas, Fernando Romero Galvan, Gabriela Shirkey, Hesham El-Askary Sep 2025

Unraveling Crop Nitrogen-Water Dynamics With Hyperspectral-Thermal Sensing In Northern Central Valley, California, Shahryar Fazli, Surendra Maharjan, Wenzhao Li, Joshua B. Fisher, Rejoice Thomas, Fernando Romero Galvan, Gabriela Shirkey, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Ensuring global food security in the face of climate change requires optimizing crop water use and nutrient management. This study investigates the relationship between canopy nitrogen (N) and evapotranspiration (ET) across sunflower, rice, walnut, alfalfa, and plum crops using advanced remote sensing technologies. High-resolution hyperspectral data from NASAs Earth Surface Mineral Dust Source Investigation (EMIT) and thermal multispectral data from the Landsat-based OpenET system were analyzed over 1,135 km2 in California. Regression analysis revealed strong spatial association between canopy N and ET for sunflower (R2 = 0.82), rice (R2 = 0.71), and walnut (R2 = 0.68), …


Anionic Azo Dyes: Wastewater Pollutants As Functionalizing Agents For Porous Polycarbonate Membranes Aiding In Water Decolorization, Alan Jarrett Messinger, Isabella S. Mays, Brennon Craigo, Jeffrey Joering, Sean P. Mcbride Aug 2025

Anionic Azo Dyes: Wastewater Pollutants As Functionalizing Agents For Porous Polycarbonate Membranes Aiding In Water Decolorization, Alan Jarrett Messinger, Isabella S. Mays, Brennon Craigo, Jeffrey Joering, Sean P. Mcbride

Physics Faculty Research

Efficient water decolorization techniques are vital for ensuring fresh water for future generations. Azo dyes are used heavily in the textile industry and are a challenge to remove from industrial wastewater. This research expands on recent innovative work where anionic azo dyes themselves were used to functionalize track-etched porous polycarbonate filtration membranes with decolorized water obtained as a byproduct. The objective of this research is to determine whether the observed dye rejection is dependent on the magnitude of the intrinsic charge of the dye molecule or on its structure, using two selectively chosen anionic azo dye series during functionalization. The …


Milkfish (Chanos Chanos) Bones As A Biosorbent For Mercury (Ii) Contamination In Water, Seth Uriel K. Neri, Ethan Kyle Mangao, Christian Kevin F. Redoblado, Anthony Cesar Y. Ponce, Roby Boy P. Riego, Jupiter O. Yap Aug 2025

Milkfish (Chanos Chanos) Bones As A Biosorbent For Mercury (Ii) Contamination In Water, Seth Uriel K. Neri, Ethan Kyle Mangao, Christian Kevin F. Redoblado, Anthony Cesar Y. Ponce, Roby Boy P. Riego, Jupiter O. Yap

Sinaya: A Philippine Journal for Senior High School Teachers and Students

Heavy metals, such as mercury contamination in water sources are a major environmental and public health issue in many countries. Traditional methods for removing heavy metals from water are effective but often costly and unsustainable and may produce secondary waste. Recent trends favor more sustainable alternatives, such as biosorbents in treating water with heavy metals. Milkfish (Chanos chanos), a common fish in the Philippines, contains hydroxyapatite in the bones that can bind with heavy metals through physical and chemical adsorption mechanisms. This study aims to evaluate the mercury (II) reduction capacity of biosorbent derived from milkfish bones in water, specifically …


New Precipitation Is Scarce In Deep Soils: Findings From 47 Forest Plots Spanning Switzerland, Emily I. Burt, Scott T. Allen, Sabine Braun, Simon Tresch, James W. Kirchner, Gregory R. Goldsmith Aug 2025

New Precipitation Is Scarce In Deep Soils: Findings From 47 Forest Plots Spanning Switzerland, Emily I. Burt, Scott T. Allen, Sabine Braun, Simon Tresch, James W. Kirchner, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

As precipitation infiltrates into soils, it can recharge them, displace previously stored waters, or bypass already-filled pores. Using 3,697 δ2H and δ18O measurements of water collected nearly monthly over >3 years in 47 forest plots across Switzerland, we present a systematic investigation of the controls on mobile soil water transport. We quantified the lags and damping of water as it percolates downward using young water fraction analysis (Fyw), and the fractions of soil water composed by precipitation that fell within the previous month (new water fractions, Fnew). The Fnew of water sampled in surface soils ranged …


Mixture Effects On Metal Accumulation In The Asian Clam, Corbicula Fluminea, Mark A. Huff Aug 2025

Mixture Effects On Metal Accumulation In The Asian Clam, Corbicula Fluminea, Mark A. Huff

Electronic Theses and Dissertations

Field collected Corbicula fluminea were exposed to trace level copper, lead, and zinc with the aim of examining the preferential accumulation between the soft tissue and shell. Metal levels were based on those in a permitted industrial effluent. At 1X effluent and 2X effluent exposure levels, copper was found to preferentially accumulate in the clam soft tissue, lead was found to preferentially accumulate in the clam shell, and zinc was found to excrete back into the diluent after preferentially accumulating in the clam soft tissue. When exposed as a mixture at 1X effluent levels, copper and lead were found to …


Highly Contaminated Sediments From The Gowanus Canal (New York) Superfund Site: An Environmental Forensic Approach, Michael A. Kruge, Kevin K. Olsen, Eric A Stern, Maria Mastalerz, Albert Permanyer Jul 2025

Highly Contaminated Sediments From The Gowanus Canal (New York) Superfund Site: An Environmental Forensic Approach, Michael A. Kruge, Kevin K. Olsen, Eric A Stern, Maria Mastalerz, Albert Permanyer

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The 2.5 km long Gowanus Canal (Brooklyn, NY, USA) is a severely contaminated urban waterway dating from the mid-19th century, listed as a US Environmental Protection Agency (USEPA) Superfund site since 2010. Applying an environmental forensics approach to the extensive USEPA data set, we detect systematic variations in parent PAH ring number distributions in the canal sediments, as well as an extraordinary enrichment in organic carbon. We subjected a supplemental sample set to a more detailed analysis by quantitative pyrolysis-GC-MS, Rock-Eval pyrolysis, and organic petrology. With these sensitive methods, we can confirm the alkyl-PAH fingerprint of coal tar (a legacy …


Green Innovation: Optimizing The Potential Of Plastic Waste As An Alternative To Fossil Fuels, Hani Alfiyani, Evi Gusmayanti, Nelly Wahyuni Jul 2025

Green Innovation: Optimizing The Potential Of Plastic Waste As An Alternative To Fossil Fuels, Hani Alfiyani, Evi Gusmayanti, Nelly Wahyuni

Journal of Environmental Science and Sustainable Development

Plastic bag waste has the potential to be converted into alternative fuel oil through the pyrolysis method. This study applies the principle of thermal pyrolysis, conducted without oxygen, at the Edelweis Integrated Waste Management Site. The purpose is to analyze the characteristics of fuel oil derived from plastic bag waste based on parameters such as density, viscosity, calorific value, and acid number, as well as to estimate the potential fuel oil yield from plastic bag waste in Pontianak City. The results show that the density, viscosity, and calorific value of the produced fuel oil meet or closely approach standard requirements. …


Electrochemistry Behind Pfas: Mechanistic And Analytical Approach For Sensing And Degradation Strategies, Jonathan Josue Calvillo Solis Jul 2025

Electrochemistry Behind Pfas: Mechanistic And Analytical Approach For Sensing And Degradation Strategies, Jonathan Josue Calvillo Solis

Open Access Theses & Dissertations

Understanding the fundamental electrochemistry of perfluoroalkyl substances (PFAS) is key to developing effective water remediation and sensing strategies. This work explores the thermodynamics and kinetics of perfluorooctanoic acid (PFOA) electroreduction, focusing on C-F bond cleavage. These insights were applied to design a highly sensitive electrochemical sensor for detecting trace levels of PFOA in water. This dissertation focuses on the electrochemical investigation of the reduction reaction of PFOA in aqueous and organic media employing different electrode materials. This exploration allows to understand the defluorination reaction of PFAS to further propose potential strategies for water treatment and PFOA electrosensing. Through electrochemical, spectroscopical …


Electrocatalytic Degradation Of Methylene Blue Using Graphene Oxide, Antimony Oxide, And Graphene Oxide-Supported Antimony Oxide Ink-Based Electrodes, Maria Irene Myers Armas Jul 2025

Electrocatalytic Degradation Of Methylene Blue Using Graphene Oxide, Antimony Oxide, And Graphene Oxide-Supported Antimony Oxide Ink-Based Electrodes, Maria Irene Myers Armas

Theses and Dissertations

This study investigates the electrocatalytic degradation of methylene blue (MB) using copper mesh electrodes coated with graphene oxide (GO), antimony oxide (Sb₂O₃), and their composite (GO/Sb₂O₃). These materials were evaluated across a pH range of 2 to 8 using sodium sulfate as the supporting electrolyte. UV-Vis spectroscopy at 665 nm confirmed dye degradation, with removal efficiencies reaching up to 95% at pH 2. However, degradation decreased at higher pH, with 40 – 60% removal at pH 8, depending on the electrode. Kinetic analyses revealed optimum performance under acidic conditions. GO/Sb₂O₃ electrodes demonstrated the most consistent and effective performance across all …