Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, 2020 University of Arkansas, Fayetteville
Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, Shane Ylagan
Crop, Soil and Environmental Sciences Undergraduate Honors Theses
The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4·6H2O) is an understudied material that can be created from Pcontaining wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple super phosphate (TSP) on corn (Zea mays) and soybean (Glycine max) response in a 79-day greenhouse ...
Heavy Metals In Particulate Matter In Spokane County, 2020 Eastern Washington University
Heavy Metals In Particulate Matter In Spokane County, Delaney M. White
2020 Symposium Posters
Heavy metals in particulate matter (e.g., dust) have multiple negative health ramifications for humans including cancer, infertility, and reduced lung function. The Spokane Regional Clean Air Agency (SRCAA) has seven air quality monitoring stations around Spokane County to measure total levels of PM2.5 (particles with a diameter less than 2.5 micrometers) and PM10 (particles with a diameter less than 10 micrometers). For comparison, the width of a human hair is between 50 and 70 micrometers. The objective of this research is to examine the heavy metal composition of the particulate matter including elements such as lead, copper ...
Massive Peatland Carbon Banks Vulnerable To Rising Temperatures, 2020 University of Oregon
Massive Peatland Carbon Banks Vulnerable To Rising Temperatures, A. M. Hopple, R. M. Wilson, M. Kolton, Cassandra A. Zalman, J. P. Chanton, J. Kostka, P. J. Hanson, Jason K. Keller, S. D. Bridgham
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Peatlands contain one-third of the world’s soil carbon (C). If destabilized, decomposition of this vast C bank could accelerate climate warming; however, the likelihood of this outcome remains unknown. Here, we examine peatland C stability through five years of whole-ecosystem warming and two years of elevated atmospheric carbon dioxide concentrations (eCO2). Warming exponentially increased methane (CH4) emissions and enhanced CH4 production rates throughout the entire soil profile; although surface CH4 production rates remain much greater than those at depth. Additionally, older deeper C sources played a larger role in decomposition following prolonged warming. Most troubling ...
Chemical Transformation Of Biomass Burning Organic Aerosols Due To Photolytic Aging, 2020 William & Mary
Chemical Transformation Of Biomass Burning Organic Aerosols Due To Photolytic Aging, Hongmin Yu
Undergraduate Honors Theses
Biomass burning organic aerosol (BBOA), organic aerosol that derived from burning of biomass fuels, has been a major research focus because of its special role in the global budget of atmospheric chemistry and radiative forcing. Due to its chemical complexity, there are gaps in our knowledge about the chemical aging processes of BBOA in the atmosphere. Since many photochemical aging experiments on BBOA are usually conducted for only a few hours, less is known about the photo-aging pathways of the system over an extended timescale. This study presents the analyses of three BBOA filter samples derived from three types of ...
Mesoporous Adsorbents For Perfluorinated Compounds, 2020 East Tennessee State University
Mesoporous Adsorbents For Perfluorinated Compounds, Bertha Lotsi
Electronic Theses and Dissertations
Effective adsorbents for polyfluorinated compounds (PFCs) were successfully prepared. And they were tested in the adsorption of perfluorooctanoic and perfluorooctanesulfonic acids. Bridged silsesquioxanes containing secondary and tertiary amino groups were synthesized by sol-gel condensation of bis[3-(trimethoxysilyl)propyl]amine and bis[3-(methylamino)propyl]-trimethoxysilane in acidic media with surfactants. Obtained materials are mesoporous with a high BET surface area. They combine high structural stability with a high concentration of surface amino groups serving as adsorption sites. Batch adsorption tests demonstrated their extremely high adsorption capacity on PFCs: in some experiments, it reached up to 88% of the adsorbent ...
Immobilization Of Phosphotungstic Acid On Silica Surface For Catalytic Alkylation Of Aromatic Compounds, 2020 East Tennessee State University
Immobilization Of Phosphotungstic Acid On Silica Surface For Catalytic Alkylation Of Aromatic Compounds, Anastasia Kuvayskaya
Electronic Theses and Dissertations
Superacidic mesoporous materials containing covalently embedded PTA were synthesized by sol-gel method. Tetraethyl orthosilicate (TEOS) and phosphotungstic acid (PTA) were used as precursors in the synthesis, ionic and nonionic surfactants were used as pore-forming agents, the reaction proceeded in acidic media. TEM images revealed mesoporous structure with embedded PTA clusters. FT-IR spectra of obtained materials contained characteristic bands of PTA at 957 cm-1. Synthesized catalysts had high BET surface area and high concentration of acidic sites. Alkylation of 1,3,5-trimethylbenzene by 1-decene demonstrated high catalytic activity. The catalyst obtained with Pluronic P123 as a template was the most effective ...
Spectroscopic And Computational Studies Of The Agricultural Active Ingredient Dicamba, 2020 University of Mississippi
Spectroscopic And Computational Studies Of The Agricultural Active Ingredient Dicamba, James Johnson
3,6-dichloro-2-methoxy benzoic acid, more commonly known as Dicamba, is the active ingredient in an array of pesticides used on farmlands across the globe. Dicamba’s mode of action works by mimicking the plant hormone auxin, which is synonymous to growth hormones in mammals. The mimicking of auxin results in excessive elongation and growing, which is eventually fatal for plants when the rate of growth can no longer be sustained. Dicamba has risen in prominence in recent years due to drift damage as a result of Dicamba’s high volatility. Having the ability to identify Dicamba is crucial for the ...
Chemical Composition And Source Regions Of Dry Deposition, 2020 Susquehanna University
Chemical Composition And Source Regions Of Dry Deposition, Rudi Randall
Senior Scholars Day
Air pollutants, such as nitrate, sulfate, and ammonia, can negatively affect the environment and human health. Pollutants can be removed from the atmosphere through dry deposition, in which dry particles and gases contact the ground directly, or wet deposition, in which particles and gases interact with precipitation before reaching the ground. Despite there being two ways particles and gases can be removed from the atmosphere, wet deposition has been studied more routinely and comprehensively than dry deposition. In this research, dry deposition to surfaces covered by dew or frost was examined for its chemical makeup (including cations, anions, and organic ...
An Innovative "Green" Suzuki Coupling Reaction For The Crl-232 Lab, 2020 West Chester University of Pennsylvania
An Innovative "Green" Suzuki Coupling Reaction For The Crl-232 Lab, James W. Wheeler, David Dehm
Chemistry Student Work
A major objective of “Green Chemistry” is to provide a more modern chemical experience in the laboratory along with reducing the amount of waste generated and make the lab safer for our students. The latest effort is the continuance to update the chemical reactions in the DHE 232 Organic Chemistry Lab by employing a “water-based” Suzuki Coupling Reaction. The 2010 Nobel prize was awarded to Heck, Negishi, and Suzuki for the palladium-catalyzed cross coupling reaction. This reaction has gained wide acceptance in industry where it is used in large scale reactions to make drugs (naproxen, 5-HT1a Agonist), agricultural chemicals (Boscalid ...
385— Optimizing Nitrogen Concentrations To Maximize Lipid Yields For Biodiesel Production, Wady Jacoby, Daria Zhogina, Pavel Ananev, Lauren Saggese, Max Muller, Barnabas Gikonyo
Select subspecies of microalgae are considered to be the most promising candidates for third generation renewable resources of biodiesel. Algae not only ingest excess carbon emissions from the atmosphere, they also convert it into energy-dense lipids which can be harvested, and then transformed into biodiesel. However, before the fuel industry can adopt algae farming as a realistic alternative to fossil fuels, the process of harvesting algal lipids must be optimized further. Our research aims to make algal lipid extraction more realistic by determining the ideal growing conditions of the algae species Chlorella Vulgaris. Our research this semester focused on two ...
154— Alfalfa Hay As Non-Human Feedstock For Second Generation Biofuels: Hope Or Hoax? Part Ii, Arianna Soriano, Sofia Kostrinsky, Barnabas Gikonyo
The excessive use of fossil fuels has negatively impacted the environment because of greenhouse gas emissions. Researchers are now searching for ways to counterbalance the damage which has been done to the Earth after centuries of greenhouse gas emissions. Potential alternatives to fossil fuels include biofuels, an overlooked and cost-effective source of energy. Many efforts have been focused on the production of first-generation biofuels, fuels attained from human food sources, such as corn. First-generation biofuels have been linked to the increase in food prices, which is a problem because it negatively impacts many developing countries. Our research is geared towards ...
183— Cannabis Sativa: Pretreatment And Fiber Content Analysis, 2020 SUNY Geneseo
183— Cannabis Sativa: Pretreatment And Fiber Content Analysis, Dina Bú, Arianna Soriano, Sofia Kostrinsky, Sarah Schmidlin, Barnabas Gikonyo
Cannabis Sativa commonly known as hemp, is one of the fastest growing plants whose refined products have immense commercial value. Refined hemp is included in various products: biofuels, biodegradable plastics, textiles, dietary supplements, paper, clothing and much more. Hemp fibers are also used in construction and manufacturing applications as a way to strengthen composite products. These qualities make hemp a high yielding, sustainable, and environmentally friendly crop with the potential to yield valuable raw materials for a large number of applications. Our research evaluates the pretreatment of hemp and the comparative analysis of the fiber content thereof. Our goal is ...
Analysis Of Petroleum Products For Forensic And Environmental Applications, 2020 Longwood University
Analysis Of Petroleum Products For Forensic And Environmental Applications, Sarah Ghali, Sarah Porter
Student Showcase for Research and Creative Inquiry
In both forensic and environmental applications, it is often important to identify ignitable liquid (IL) residues, to find a suspect or to clean up an oil spill. The ASTM method is commonly used; the extraction methods vary, but the data collection is the same. The instrument used in the ASTM method is gas chromatography mass spectroscopy (GC-MS), which allows a visual identification of the IL contaminating the sample. In this study, the use of Fourier transform infrared spectrometry (FTIR) was used in conjunction with chemometric analysis. Samples were prepared were to simulate an oil spill in natural waters. Two chemometric ...
Surveillance Of Microplastic Pollution In Central Virginia Freshwater Ecosystems, 2020 Liberty University
Surveillance Of Microplastic Pollution In Central Virginia Freshwater Ecosystems, Alexandra Reddy
Senior Honors Theses
Aquatic organisms often mistake microplastic particulates (MP) as food and inadvertently ingest the particulates, which can biomagnify through the food chain. While MP ingestion is well-researched in the marine environment, little is known about microplastics in freshwater ecosystems. This project explores MP occurrence in an ecologically significant freshwater invertebrate: crayfish. Crayfish from two Central Virginia streams are collected to identify MP in the digestive tracts and gill filaments, and characterize the MP using analytical chemistry techniques. It was determined that MP were present in the digestive tracts and gill filaments of crayfish collected from both streams, and that MP frequency ...
Using Electrocoagulation To Remove Perfluoroalkyl And Polyfluoroalkyl Substances (Pfas) From Contaminated Water, 2020 University of Nebraska-Lincoln
Using Electrocoagulation To Remove Perfluoroalkyl And Polyfluoroalkyl Substances (Pfas) From Contaminated Water, Amy Yanagida
UCARE Research Products
Perfluoroalkyl and Polyfluoroalkyl substances (PFAS) are a family of manmade chemicals that are used to improve the quality of several commercial products by making them resistant to heat, oil, stains, grease and water. Unfortunately, the chemical properties that make PFAS useful from an industrial perspective also make them mobile and recalcitrant once released into the environment. We used electrocoagulation to run a direct current through contaminated water to generate a zinc floc to precipiate PFAS out of water.
Geochemical Tracers Of Arctic Ocean Processes: A Study Of Gallium, Barium, And Vanadium, 2020 University of Southern Mississippi
Geochemical Tracers Of Arctic Ocean Processes: A Study Of Gallium, Barium, And Vanadium, Laura M. Whitmore
The Arctic Ocean is linked to the global oceans and climate through its connectivity with the North Atlantic Ocean and the regional thermohaline deep water formation sites. It’s also a region undergoing rapid environmental change. To inform the community of potential changes in geochemical and biogeochemical cycles, this dissertation addresses three dissolved geochemical tracers (gallium, barium, and vanadium) as indicators of Arctic Ocean processes. Gallium is tested as a replacement for nutrient-type tracers in an effort to deconvolve Pacific and Atlantic derived waters in the Arctic Ocean basins. These water masses carry different heat and salt content and can ...
Mercury And Other Trace Metal Analysis In Bat Guano, 2020 Western Kentucky University
Mercury And Other Trace Metal Analysis In Bat Guano, Amanda Lee Houchens
Masters Theses & Specialist Projects
Heavy metal pollution in the environment pose risks to ecosystems and the populations that reside in them. Mercury, lead, and cadmium negatively impact humans by way of neurological disorders, various cancers, and damage the reproductive organs, kidneys, and lungs. Bats have been studied as a bioindicator species to identify possibly elevated levels of these metals in the environment. Previous studies have identified correlation between metal concentrations within bat tissues and fur. Many bat species are endangered or at risk due to white-nose syndrome so collection of tissues and fur for analysis can impose stress on bat colonies. This study investigates ...
Brown Carbon Production By Aqueous-Phase Interactions Of Glyoxal And So2, 2020 University of San Diego
Brown Carbon Production By Aqueous-Phase Interactions Of Glyoxal And So2, David O. De Haan, Kevin Jansen, Alec D. Rynaski, W. Ryan P. Sueme, Ashley K. Torkelson, Eric T. Czer, Alexander K. Kim, Michael A. Rafla, Audrey C. De Haan, Margaret A. Tolbert
Chemistry and Biochemistry: Faculty Scholarship
Oxalic acid and sulfate salts are major components of aerosol particles. Here, we explore the potential for their respective precursor species, glyoxal and SO2, to form atmospheric brown carbon via aqueous-phase reactions in a series of bulk aqueous and flow chamber aerosol experiments. In bulk aqueous solutions, UV- and visible-light-absorbing products are observed at pH 3–4 and 5–6, respectively, with small but detectable yields of hydroxyquinone and polyketone products formed, especially at pH 6. Hydroxymethanesulfonate (HMS), C2, and C3 sulfonates are major products detected by electrospray ionization mass spectrometry (ESI-MS) at pH 5. Past studies ...
Ac And Dc Differential Bridge Structure Suitable For Electrochemical Interfacial Capacitance Biosensing Applications, Sara Neshani, Charles K. A. Nyamekye, Scott Melvin, Emily A. Smith, Degang J. Chen, Nathan Neihart
Electrical and Computer Engineering Publications
This paper presents a capacitive differential bridge structure with both AC and DC excitation and balancing capability for low cost electrode-solution interfacial capacitance biosensing applications. The proposed series RC balancing structure offers higher sensitivity, lower susceptibility to common-mode interferences, and drift control. To evaluate the bridge performance in practice, possible effects of initial bridge imbalance due to component mismatches are investigated considering the required resolution of the balancing networks, sensitivity, and linearity. This evaluation is also a guideline to designing the balancing networks, balancing algorithm and the proceeding readout interface circuitry. The proposed series RC bridge structure is implemented along ...
Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean, 2020 ommonwealth Scientific and Industrial Research Organisation (CSIRO), Australia
Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean, Sarah J. Lawson, Cliff S. Law, Mike J. Harvey, Thomas G. Bell, Carolyn F. Walker, Warren J. De Bruyn, Eric S. Saltzman
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Atmospheric methanethiol (MeSHa), dimethyl sulfide (DMSa) and acetone (acetonea) were measured over biologically productive frontal waters in the remote southwest Pacific Ocean in summertime 2012 during the Surface Ocean Aerosol Production (SOAP) voyage. MeSHa mixing ratios varied from below the detection limit (< 10 ppt) up to 65 ppt and were 3 %–36 % of parallel DMSa mixing ratios. MeSHa and DMSa were correlated over the voyage (R2=0.3, slope = 0.07) with a stronger correlation over a coccolithophore-dominated phytoplankton bloom (R2=0.5, slope 0.13). The diurnal cycle for MeSHa shows similar behaviour to DMSa with mixing ratios varying by a ... 10 ppt)>