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Full-Text Articles in Chemistry

Isolation And Determination Of The Composition And Structural Components That Comprise Dissolved Organic Matter Using Normal Phase Liquid Chromatography, Jonathan A. Long Jr May 2021

Isolation And Determination Of The Composition And Structural Components That Comprise Dissolved Organic Matter Using Normal Phase Liquid Chromatography, Jonathan A. Long Jr

LSU New Orleans Theses and Dissertations

A comprehensive understanding of the reactivity associated with organic carbon is critical for recognizing the behavior of newly formed compounds in aquatic environments. In an effort to study the reactivity of complex mixtures, understanding the different processes affiliated with them are key. Understanding the reactivity associated with organic carbon can help to improve chromatographic separation. Using a combination of light and heavy crude oil, a separation procedure was developed to obtain a complete representation of the aromatic subfraction of the crude oil sample. The crude oils were separated into four distinct fractions based on the number of condensed aromatic rings …


Biodiesel Production By Esterification Of Ricinoleic Acid Over A Series Of Synthesized Sulfated Zirconia Catalysts, Elianaso Elimbinzi, Stephen S Nyandoro May 2021

Biodiesel Production By Esterification Of Ricinoleic Acid Over A Series Of Synthesized Sulfated Zirconia Catalysts, Elianaso Elimbinzi, Stephen S Nyandoro

Tanzania Journal of Science

A series of sulfated zirconia (SZ) were synthesized and evaluated for catalytic esterification of ricinoleic acid obtained from the castor oil with butanol at 110 °C. The effect of alcohols’ chain length was studied using butanol (C4), propanol (C3), ethanol (C2) and methanol (C1) at 65 °C, and reflux of corresponding alcohol boiling points. The synthesized catalysts were characterized using nitrogen porosimetry, X-ray powder diffraction, thermogravimetric analysis and Diffuse Reflectance Infrared Fourier Transform Spectroscopy. Analysis of ricinoleic conversion was performed using gas chromatography. Sulfuric acid loading improved the surface area of zirconia at a lower dose. The surface areas of …


Addressing Uncertainties Of Polychlorinated Biphenyls In Schools, Alice Fan May 2021

Addressing Uncertainties Of Polychlorinated Biphenyls In Schools, Alice Fan

Master's Projects and Capstones

Despite the potential neurological health deficits resulting from polychlorinated biphenyls, there is a lack of inhalation studies and regulations to protect students and teachers who are widely exposed to PCBs in older (1950 to 1979) schools. To estimate the extent of PCB detections in Los Angeles County schools, I applied a mathematical model to estimate the range of PCB detections in schools built between 1950 and 1984. I estimate the range of 17-34% PCB detections of open schools within Los Angeles County. Next, I reviewed exposure tools provided by the US EPA to bridge the uncertainty gaps between ingestion and …


Scan Of The Advantage Of Using Biofuels, Ethanol, Ana Carla Bueno May 2021

Scan Of The Advantage Of Using Biofuels, Ethanol, Ana Carla Bueno

Symposium of Student Scholars

The environment is the big sink where all the human waste produced is deposited, mainly the pollutant gases from cars. It is inevitable not to contaminate drinking water, air, and all other ecosystems on the planet, and it was from these concerns that scientists began to develop alternative ways to mitigate the side effects of pollution. Currently, there are many strategies to soften the emission of pollutant gases into the atmosphere, and the biggest competitor of traditional fossil fuel is biofuels. The big challenge in the production of this type of fuel is the competition with the conventional fossil fuel, …


Developing An Inquiry-Based Laboratory Project For Chem 142l Course At Bsu, Manuel Pina May 2021

Developing An Inquiry-Based Laboratory Project For Chem 142l Course At Bsu, Manuel Pina

Honors Program Theses and Projects

In addition to content knowledge, critical and independent thinking, scientific reasoning, and problem-solving skills are essential in preparing next generation of successful workforce. Since one of the biggest advantages of STEM disciplines is a “must-have” hands-on laboratory experience, it is intuitive to exploit this learning space to reinforce afore-mentioned skills. In this context, project-based (PBL) or inquiry-based (IBL) laboratory experiences are rapidly becoming mainstream pedagogical choice for many STEM instructors across United States.[1-4] PBL, and IBL are learning experiences that offer students an opportunity to experience realistic scientific process of discovery through carefully designed inquiry-driven and/or open-ended investigative laboratory …


Effects Of Environmental Change On Ancestral Pueblo Fishing In The Middle Rio Grande, Jonathan William Dombrosky May 2021

Effects Of Environmental Change On Ancestral Pueblo Fishing In The Middle Rio Grande, Jonathan William Dombrosky

Anthropology ETDs

It has long been assumed that fishes were unimportant in the diet of past Pueblo people in the U.S. Southwest. Yet, small numbers of fish remains are consistently recovered from Late pre-Hispanic/Early Historic archaeological sites in the Middle Rio Grande of New Mexico. The end of drought conditions may have impacted food choice and fishing decisions during this time. I use behavioral ecology to understand how fishing could have been an optimal food-getting strategy for Ancestral Pueblo farmers. Stable isotope analysis offers a way to account for environmental change. I provide a refined 13C Suess correction model to support …


Comparative Analysis Of Azo Dye Restriction In The International Textile Industry, Kayla Demark May 2021

Comparative Analysis Of Azo Dye Restriction In The International Textile Industry, Kayla Demark

Apparel Merchandising and Product Development Undergraduate Honors Theses

Azo dyes are the most used type of dye in the textile industry. Some of these dyes have the potential to be extremely toxic to both human health and the environment. While regulations of these dyes vary across the world, it is suggested that not enough is being done to protect consumers and the environment from potentially harmful azo dyes (Rawat et al., 2016). It is the responsibility of apparel companies to ensure that their products that contain azo dyes are safe for consumers.

The purpose of this study was to understand how azo dyes and their by-products are restricted …


Isolated Point Discharges Into Coastal Swashes As Nutrient Sources To Coastal Waters, Mary E. Olsen May 2021

Isolated Point Discharges Into Coastal Swashes As Nutrient Sources To Coastal Waters, Mary E. Olsen

Honors Theses

Coastal water quality in the Grand Strand of South Carolina is directly influenced by human activities. Nutrient-rich runoff, stemming from numerous anthropogenic sources, finds its way into coastal waters through freshwater inputs often through tidal creeks, termed swashes. In order to better describe the amount of nutrient inputs into Singleton Swash and White Point Swash, we examine anthropogenic runoff from isolated identifiable point discharges and their nutrient concentrations. We report concentrations of dissolved inorganic nitrogen (DIN, as the sum of nitrate, nitrite and ammonium) and phosphate in discharge and creek water. We hypothesize that nutrient concentrations of isolated, minor point …


A Conductivity Analysis Of A Newly Synthesized Poly(Ethylene Glycol) Methyl Ether Hydroxide Electrolyte, Sarah Marie Peterson May 2021

A Conductivity Analysis Of A Newly Synthesized Poly(Ethylene Glycol) Methyl Ether Hydroxide Electrolyte, Sarah Marie Peterson

Honors Theses

This thesis investigates the synthesis and conductive properties of a Poly (ethylene glycol) methyl ether-based polymer electrolyte. The goal of the synthesis is to enhance the hydroxide ion conduction properties of the polymer with its cationic groups attached. The MePEG backbone contained seven ethylene glycol groups and was modified to substitute the hydroxide group in the MePEG with trimethylamine. In addition, the bromide added in the synthesis was exchanged for hydroxide ions to allow for the transportation of hydroxide ions in polymeric electrolytes that can be used in Anion Exchange Membrane Fuel Cells. The newly synthesized polymer was compared to …


006— Pretreatment And Fiber Content Analysis Of Cannabis Sativa, Dina Bu, Jessica Roggie, Sarah Schmidlin, Barnabas Gikonyo Apr 2021

006— Pretreatment And Fiber Content Analysis Of Cannabis Sativa, Dina Bu, Jessica Roggie, Sarah Schmidlin, Barnabas Gikonyo

GREAT Day Posters

Cannabis sativa commonly known as hemp is one of the fastest-growing plants whose refined products have immense commercial value. Various products include refined hemp such as: biofuels, biodegradable plastics, textiles, dietary supplements, paper, clothing, and much more. Hemp fibers are also used in construction and manufacturing applications by strengthening their composite products. Hemp is a high yielding, sustainable, and environmentally friendly crop due to its various qualities, and has the potential to yield valuable raw materials for a great number of applications. Our research evaluates the pretreatment of hemp as well as the comparative analysis of the fiber content thereof. …


041— Fiber Decomposition And Pretreatment Analysis Of Cannabis Sativa L.: Hemp, Dina Bu, Jessica Roggie, Sarah Schmidlin, Barnabas Gikonyo Apr 2021

041— Fiber Decomposition And Pretreatment Analysis Of Cannabis Sativa L.: Hemp, Dina Bu, Jessica Roggie, Sarah Schmidlin, Barnabas Gikonyo

GREAT Day Posters

Hemp is a subspecies of Cannabis sativa L. along with marijuana, yet the two differ in chemical constituent levels of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Hemp contains 0.3% THC, compared to marijuana 17.1%, allowing it to be a safe and compelling biomass for investigation. The refined products of hemp are vast due to its fast-growing properties; therefore various commercial industries have included refined hemp in biofuels, biodegradable plastics, textiles, dietary supplements, paper, clothing, and much more. Construction and manufacturing applications have also been seen to include hemp to strengthen their composite products. The high-yielding, sustainable, and environmentally friendly qualities …


Characterization Of Uranium, Lead, And Rare Earth Element Pollution In Natural Soils And Sediments, Hope Rasmussen Apr 2021

Characterization Of Uranium, Lead, And Rare Earth Element Pollution In Natural Soils And Sediments, Hope Rasmussen

Civil and Environmental Engineering Theses and Dissertations

Heavy metals in the environment add to the global burden of pollution, negatively impacting public health and ecosystem resilience. This study included projects regarding uranium (U), lead (Pb), and rare earth elements (REE) in natural samples, due to their known toxicity, ubiquity, and relevance in context to recent pollution trends. The first project focused on testing the potential of using a hydroxyapatite product as a remediation solution for U-contaminated groundwater and soil at an EPA Superfund site. The results showed that the U was sequestered in a highly crystalline mineral form within the solids, guiding the EPA to specify the …


Soil Quality Indices As Affected By Long-Term Burning, Irrigation, Tillage, And Fertility Management, Helen C.S. Amorim, Amanda Ashworth, Kristofor R. Brye, Brian J. Wienhold, Mary C. Savin, Phillip R. Owens, Sergio Silva Mar 2021

Soil Quality Indices As Affected By Long-Term Burning, Irrigation, Tillage, And Fertility Management, Helen C.S. Amorim, Amanda Ashworth, Kristofor R. Brye, Brian J. Wienhold, Mary C. Savin, Phillip R. Owens, Sergio Silva

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Understanding the impacts of long-term agricultural practices on soil quality (SQ) is key for sustaining agroecosystem productivity. This study investigated conventional and no-tillage (NT), residue burning and no burning, residue level (high and low), and irrigation (irrigated and dryland) effects on soil properties, SQ, and crop yields following 16 yr of a wheat (Triticum aestivum L.)–soybean [Glycine max (L.) Merr.] double-crop system via the Soil Management Assessment Framework (SMAF). A field experiment was conducted in the Lower Mississippi River Delta region on a silt-loam soil. Bulk density, soil organic C (SOC), total N (TN), pH, electrical conductivity (EC), …


Coastal Watershed Monitoring And Management: Geomorphology, Geochemistry, And Hydrologic Modeling Of Los Peñasquitos Creek, Ca, Ravleen Khalsa-Basra Jan 2021

Coastal Watershed Monitoring And Management: Geomorphology, Geochemistry, And Hydrologic Modeling Of Los Peñasquitos Creek, Ca, Ravleen Khalsa-Basra

Theses

Rivers in semi-arid climates are directly influenced by local geographic and hydrologic conditions and impacted by modifications to hydrology via urbanization. Changes can influence erosion, morphology, habitat sustainability, and watershed health. In highly urbanized southern California coastal regions, these rare open spaces provide vital ecosystem services. Los Peñasquitos Creek in San Diego County is one such watershed. Using stream surveying and laboratory methods we quantified channel characteristics, grain size distribution, total metal concentration [M], organic carbon (%OC), and phosphate to longitudinally characterize the creek for improved management. Results identified three distinct reaches in the watershed (upper, middle, lower). Downstream, depth …


Carbon Dioxide And Particulate Matter Concentration On Hampton Roads Air Quality, Gregory Hubbard Jan 2021

Carbon Dioxide And Particulate Matter Concentration On Hampton Roads Air Quality, Gregory Hubbard

OUR Journal: ODU Undergraduate Research Journal

Hampton Roads has been a maritime crossroads for the last 400 years. Industrialization has impacted the coastal region for the last 250 years. The expansion of the Port of Virginia in 2019 has created dense traffic in the region resulting in impacts to air quality. Two waste products that affect humans are particulate matter and carbon dioxide. Both respective emissions can cause adverse effects on humans, such as asthma, some lung cancers, and other respiratory distress. Scientists and health practitioners are studying the effects of particulate matter on human health. Hampton Roads, in particular, because of its unique location on …


Characterization Of Microbial Populations In Landfill Leachate, Umut M. Bicim, Hanna Fulford, Lori A. Hoagland, Alejandro R. Sanchez, Amisha D. Shah, Inez Hua Jan 2021

Characterization Of Microbial Populations In Landfill Leachate, Umut M. Bicim, Hanna Fulford, Lori A. Hoagland, Alejandro R. Sanchez, Amisha D. Shah, Inez Hua

Discovery Undergraduate Interdisciplinary Research Internship

In the United States, municipal solid waste (MSW) landfills remain a potential mining source of recoverable materials, including but not limited to critical, precious, and rare earth metals found in electronic waste. This is possible due to collectible leachate that filters through MSW landfills, carrying metals, nutrients of value, and microbes—some of which may hold key metal bioleaching properties—within. The purpose of this study is to begin analyzing leachate from MSW landfills in the American Midwest to understand the composition of microbial communities within these landfills. Landfill leachate samples sourced in northern Indiana, representing the landfill process during unique times …


The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes Jan 2021

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO4 complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …


Artificial Reefs: A History, A Science, A Technology, Mairead D. Farrell Jan 2021

Artificial Reefs: A History, A Science, A Technology, Mairead D. Farrell

Honors Theses

Over the past 60 years, artificial reefs have expanded beyond the definition of a technology, and in turn have developed into a unique branch of marine science. To better emphasize this growth and separation, a brief history of artificial reef development and usage in chapter two shows some of the key shifts over time in this technology’s purpose and the materials used to achieve that goal. Likewise, to indicate the scientific development of artificial reefs as a branch of marine science, their usage for discovery and research is recorded in chapter three, along with the exponential increase in published scientific …


Legacy And Emerging Per- And Polyfluoroalkyl Substances : Analysis, Environmental Distribution, And Bioconcentration, Richard Anthony Brase Jan 2021

Legacy And Emerging Per- And Polyfluoroalkyl Substances : Analysis, Environmental Distribution, And Bioconcentration, Richard Anthony Brase

Legacy Theses & Dissertations (2009 - 2024)

Per- and polyfluoroalkyl substances (PFAS) constitute a broad class of anthropogenic chemicals that have been used in numerous industrial and consumer-product applications since the late 1940s. The environmental persistence of these compounds in combination with their widespread commercial use have led PFAS to be recognized as contaminants of concern on the global scale. Despite regulatory efforts calling for the decreased use of certain perfluorocarboxylic and -sulfonic acids referred to as “legacy” PFAS, these compounds continue to be detected in both environmental and biological matrices. Moreover, manufacturers have begun to replace the legacy PFAS with emerging alternatives for which the regulations …


Bow Lake (Station 3 - Bennett) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Bow Lake (Station 3 - Bennett) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Bow Lake, Station 3 Bennett (Barrington and Northwood, NH) for 2021.


Lovell Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Lovell Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Lovell Lake (Sanbornville, NH) for sampling efforts in 2021.


Baboosic Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Baboosic Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Baboosic Lake (Amherst and Merrimack, NH) for 2021.


Province Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Province Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Province Lake (Wakefield, NH and Parsonsfield, ME) for 2021.


Belleau Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Belleau Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Belleau Lake in Wakefield, NH for 2021.


Balch Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Balch Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Balch Pond (Wakefield, NH; Acton and Newfield, ME) for sampling efforts up to 2021.


Artisanal Mining Impacts In Urbanized Semi-Arid Environments: Lessons From Historic Arsenic Mining Near San Diego, California, James A. Wright Jan 2021

Artisanal Mining Impacts In Urbanized Semi-Arid Environments: Lessons From Historic Arsenic Mining Near San Diego, California, James A. Wright

Theses

Anomalously elevated arsenic concentrations occur at an abandoned artisanal mine site in an open space recreational park in urban San Diego County, California. Although mining at the site ceased 100 years ago little to no remediation efforts took place leaving shafts, adits, waste piles and derelict infrastructure accessible by inquisitive hikers and adventurers frequenting Black Mountain Open Space Park. This study evaluates the geochemical mechanisms of As transport downgradient from the mine and examines the contribution of both climate and urbanization on the restriction of As mobility. Sediment As concentrations reach 2,320 mg/kg (483 times background crustal concentrations; n=73) along …


Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah Jan 2021

Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah

Graduate Theses, Dissertations, and Problem Reports (ETD)

Valorization of Xylan in Agroforestry Waste Streams.

Harrison Appiah

Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …


Bow Lake (Station 1 - Ledges) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Bow Lake (Station 1 - Ledges) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Bow Lake, Station 1 Ledges (Barrington and Northwood, NH) for 2021.


Lake Ivanhoe 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Lake Ivanhoe 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Lake Ivanhoe (Wakefield, NH) for sampling efforts in 2021.


Pine River Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft Jan 2021

Pine River Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

No abstract provided.