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An Overview Of Dynamic Heterogeneous Oxidations In The Troposphere, Elizabeth A. Pillar-Little, Marcelo I. Guzman 2018 University of Kentucky

An Overview Of Dynamic Heterogeneous Oxidations In The Troposphere, Elizabeth A. Pillar-Little, Marcelo I. Guzman

Chemistry Faculty Publications

Due to the adverse effect of atmospheric aerosols on public health and their ability to affect climate, extensive research has been undertaken in recent decades to understand their sources and sinks, as well as to study their physical and chemical properties. Atmospheric aerosols are important players in the Earth’s radiative budget, affecting incoming and outgoing solar radiation through absorption and scattering by direct and indirect means. While the cooling properties of pure inorganic aerosols are relatively well understood, the impact of organic aerosols on the radiative budget is unclear. Additionally, organic aerosols are transformed through chemical reactions during atmospheric ...


High-Dimensional Isotope Relationships, Yuyang He 2018 Louisiana State University

High-Dimensional Isotope Relationships, Yuyang He

LSU Doctoral Dissertations

High-dimensional isotope relationships describes the relationships of two or more element or position-specific (PS) elements in the same molecule or ion. It provides us more powerful tools to study reaction mechanisms and dynamics. Chapter 1 is about dual or multiple stable isotope relationship on δ-δ (or δ'-δ') space. While temporal data sampled from a closed-system can be treated by a Rayleigh Distillation Model (RDM), spatial data should be treated by a Reaction-Transport Model (RTM). Here we compare the results of a closed-system RDM to a RTM for systems with diffusional mass transfer by simulating the trajectories on nitrate's ...


Enhanced Acidity Of Acetic And Pyruvic Acids On The Surface Of Water, Alexis J. Eugene, Elizabeth A. Pillar, Agustín J. Colussi, Marcelo I. Guzman 2018 University of Kentucky

Enhanced Acidity Of Acetic And Pyruvic Acids On The Surface Of Water, Alexis J. Eugene, Elizabeth A. Pillar, Agustín J. Colussi, Marcelo I. Guzman

Chemistry Faculty Publications

Understanding the acid–base behavior of carboxylic acids on aqueous interfaces is a fundamental issue in nature. Surface processes involving carboxylic acids such as acetic and pyruvic acids play roles in (1) the transport of nutrients through cell membranes, (2) the cycling of metabolites relevant to the origin of life, and (3) the photooxidative processing of biogenic and anthropogenic emissions in aerosols and atmospheric waters. Here, we report that 50% of gaseous acetic acid and pyruvic acid molecules transfer a proton to the surface of water at pH 2.8 and 1.8 units lower than their respective acidity constants ...


Novel Relative Spontaneous Ignition Temperature Determination Using Carbon Dioxide Onset With Sta/Ir, Antonio David Trevino 2018 Stephen F. Austin State University

Novel Relative Spontaneous Ignition Temperature Determination Using Carbon Dioxide Onset With Sta/Ir, Antonio David Trevino

Electronic Theses and Dissertations

Simultaneous thermal analysis, coupled with infrared spectroscopy (STA/IR), was utilized to monitor the evolution of gaseous products during the thermal degradation of samples from Triadica sebifera (Chinese tallow), Ligustrum sinense (Chinese privet), and Ilex vomitoria (yaupon) plants. Identification of carbon dioxide was successful with a spectral match of 90.2 percent and further used in the determination of relative spontaneous ignition temperature, or RSIT. The RSIT value during the growing season for Chinese tallow, Chinese tallow stem, Chinese privet, and Yaupon were 208.4°C, 250.3°C, 210.1°C, and 232.3°C respectively. During the dormant ...


The Fate Of Arsenic In Noah’S Flood, Aaron R. Hutchison, Campbell F. Bortel 2018 Cedarville University

The Fate Of Arsenic In Noah’S Flood, Aaron R. Hutchison, Campbell F. Bortel

The Proceedings of the International Conference on Creationism

One potential consequence of Noah’s Flood would be the mobilization of toxic elements such as arsenic (As), a group 15 metalloid with a significant solubility and redox chemistry in water and a high toxicity to human beings. This paper discusses the likely chemistry of arsenic during the Flood. The Flood would have released arsenic through hydrothermal activity, volcanic eruptions, and weathering of crustal rock. Arsenic in hydrothermal fluid would likely be rapidly precipitated by sulfides. Likewise, much of the arsenic in volcanoes would actually be deposited sub-surface as sulfides. In the presence of oxygen-rich waters, these sulfide minerals can ...


Removal Of Acid Yellow 25 From Aqueous Solution By Chitin Prepared From Waste Snow Crab Legs, Chin-Chuan Wei, Inoka K. Pathiraja, Emily Fabry, Kyle Schafer, Nick Schimp, Tuo-Ping Hu, Lawrence P. Norcio 2018 Southern Illinois University Edwardsville

Removal Of Acid Yellow 25 From Aqueous Solution By Chitin Prepared From Waste Snow Crab Legs, Chin-Chuan Wei, Inoka K. Pathiraja, Emily Fabry, Kyle Schafer, Nick Schimp, Tuo-Ping Hu, Lawrence P. Norcio

SIUE Faculty Research, Scholarship, and Creative Activity

Acid Yellow 25 (AY25) is used in the textile industry for dyeing of natural and synthetic fibers, and is also used as a coloring agent in paints, inks, plastics, and leathers. Effluents from such industries are major sources of water pollution. Hence, it is important to find simple, efficient, and inexpensive ways to remove these dyes from wastewater. Here, we determined the suitability of chitin extracted from waste crab legs as an adsorbent for removing AY25 dye. The adsorption kinetics was modeled using pseudo-first order, pseudo-second order, and intraparticle diffusion equations to determine the rate controlling step. Results showed that ...


A System For Conducting Laser-Induced Fluorescence Measurements On Gas Mixtures Exposed To Alpha Radiation, Patrick Ables 2018 The University of Southern Mississippi

A System For Conducting Laser-Induced Fluorescence Measurements On Gas Mixtures Exposed To Alpha Radiation, Patrick Ables

Master's Theses

This paper documents modifications to an existing vacuum system to allow laser-induced fluorescence spectroscopy measurements within simulated atmospheres under a variety of conditions. This added capability will expand the laboratory’s ability to experimentally validate a computational model that calculates the effects of radiation within the atmosphere. The computational model could reveal radiation-induced chemical products that can be used to develop an alternative detection method that can be implemented from a safe distance. The selection of molecules for experimental validation has been limited to those which can be detected utilizing cavity ringdown spectroscopy. The current model indicates nitric oxide and ...


Utilization Of Papaya’S Sap (Carica Papaya L.) And Water Lettuce (Pistia Stratiotes) To Reduce Protein Amount On Liquid Tofu Waste, Muhammad Dzulfikar Farkhan, Naila Aliyahandra Anzani, Nabila Fikria Santoso 2018 International High School

Utilization Of Papaya’S Sap (Carica Papaya L.) And Water Lettuce (Pistia Stratiotes) To Reduce Protein Amount On Liquid Tofu Waste, Muhammad Dzulfikar Farkhan, Naila Aliyahandra Anzani, Nabila Fikria Santoso

The International Student Science Fair 2018

Liquid waste from tofu production is one of the causes of environmental pollution. This condition happens because liquid tofu waste contain protein. Protein is metabolized by bacteria formed ammonia which emits foul odor. On this research, the protein amount in liquid tofu waste is reduced by the application of papaya’s sap and water lettuce. This research is divided into several steps. First, collecting the liquid tofu waste. second, tapping the papaya’s sap. Third, poured the papaya’s sap into the tofu waste. the next step is keep the mixture between tofu waste and papaya’s sap rest for ...


Steric Effects Of Alkyl Ammonium Salts On The Combustion Of Exchanged Smectite Clays, Celeste A. Keith 2018 Stephen F. Austin State University

Steric Effects Of Alkyl Ammonium Salts On The Combustion Of Exchanged Smectite Clays, Celeste A. Keith

Electronic Theses and Dissertations

Bomb calorimetry was explored as a new method for determining the cation exchange capacity (CEC) of clays. Smectite clays were modified with several alkyl ammonium salts varying in number of carbons and the spatial orientation of the carbons about the central nitrogen atom. The clays used, standards purchased from the Source Clay Repository, have CECs of 44, 80, 88, and 120 meq/100 g. Theoretically, the combustion energy of the organo-clays should be approximately the same for each salt. Any differences in energy would be due to the different structures of the salts and how they are oriented in the ...


Heavy Metal Accumulation In Seagrasses In Southeastern Florida, Erin Smith 2018 Halmos College of Natural Sciences and Oceanography

Heavy Metal Accumulation In Seagrasses In Southeastern Florida, Erin Smith

HCNSO Student Theses and Dissertations

Seagrass beds are among the most ecologically important systems in the marine environment. They provide the primary production to nearby coral reef and mangrove communities, and seagrasses comprise a large component of the diets of many marine organisms including fishes, small invertebrate species, and many protected species such as manatees and sea turtles. This consumption provides a pathway for many contaminants to enter the marine food web via the seagrasses. The coastal location of seagrass beds causes them to be especially susceptible to anthropogenic pollution, including accumulation of heavy metals, which has been shown to have many adverse health effects ...


Desalination Concentrate Disposal: Ecological Effects And Sustainable Solutions, Ryan Hanley 2018 University of Washington – Tacoma

Desalination Concentrate Disposal: Ecological Effects And Sustainable Solutions, Ryan Hanley

Global Honors Theses

Freshwater availability is a growing global concern, and desalination is often presented as the solution, but from this important technology comes issues of toxic waste. Ecosystems are delicate areas that contain species adapted to that specific location, and any chemical or physical changes can disrupt the fitness of species. The concentrate byproduct waste from desalination plants is toxic to species if the concentrate is not compatible with the receiving water body. A critical review of scientific articles, industry-leading books, conversations with industry experts, and information from the American Membrane Technology Association conference was used to analyze the current knowledge. Species ...


Synthesis And Characterization Of Organically Modified Hectorites For Sequestration Of Pfaas From Contaminated Drinking Water, Alexandra Pagano 2018 Union College

Synthesis And Characterization Of Organically Modified Hectorites For Sequestration Of Pfaas From Contaminated Drinking Water, Alexandra Pagano

Honors Theses

Perfluoroalkyl Acids (PFAAs), a family of industrial chemicals, are found in household products such as pizza boxes, microwave popcorn bags, and non-stick pans. PFAAs of different carbon chain lengths and ionic head groups exist, such as PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid). Used without regulation in industry for decades, PFAAs only recently became recognized as contaminants of emerging concern, since they are bioaccumulative in organisms, persistent in the environment, and toxic. PFAAs are known to accumulate in the blood, liver and kidneys, and drinking water contaminated with PFAAs has been linked to certain types of cancer. Therefore, it ...


Investigation On The Dissociative Photoionization Mechanism Of Furfural, Investigation Of The Absolute Photoionization Cross Sections Of Three Potential Propargylic Fuels, And Ab Initio Analysis On Potential Superbases Of Several Hyperlithiated Species: Li3f2o And Li3f2(Oh)N (N = 1, 2, 3), Matthew Winfough 2018 University of San Francisco

Investigation On The Dissociative Photoionization Mechanism Of Furfural, Investigation Of The Absolute Photoionization Cross Sections Of Three Potential Propargylic Fuels, And Ab Initio Analysis On Potential Superbases Of Several Hyperlithiated Species: Li3f2o And Li3f2(Oh)N (N = 1, 2, 3), Matthew Winfough

Master's Theses

This thesis presents the study photoionization cross sections of three different propargylic biofuels; dipropargyl ether, propargyl alcohol, and propargylamine, in chlorine radical-initiated combustion experiments at the Chemical Dynamics Beamline (9.0.2) at the Advanced Light Source of the Ernest Orlando Berkeley National Laboratory in Berkeley, California. Additionally, the unimolecular dissociative photoionization mechanism of furfural was studied using photoelectron photoionization coincidence (PEPICO) spectroscopy at the vacuum ultraviolet beamline at the Swiss Light Source of the Paul Scherrer Institut in Villigen, Switzerland. Dissociation products and mechanisms for furfural were identified over a photon energy range of 10.9 to 14.5 ...


Assessment Of The Viability Of Microwell Plates As Sample Holders For Analytical Excitation-Emission Spectroscopy Of Polyaromatic Hydrocarbons In 75% Ethanol, Lauren M. Ridley-Hoffman 2018 Seton Hall University

Assessment Of The Viability Of Microwell Plates As Sample Holders For Analytical Excitation-Emission Spectroscopy Of Polyaromatic Hydrocarbons In 75% Ethanol, Lauren M. Ridley-Hoffman

Seton Hall University Dissertations and Theses (ETDs)

Polyaromatic hydrocarbons (PAHs) in the environment are a significant concern as many compounds in this class are potential carcinogens. PAHs resulting from petroleum spills can contaminate natural waters and the products obtain from them (fish and fish products in particular). Previous studies by Pena, et. al. on ethanolic extracts of organs from menhaden captured in the vicinity of the Deepwater Horizon (Macondo oil well) spill have shown that fluorescence excitation spectroscopy is a useful technique for detecting the presence of PAH metabolites and fluorescent vitamins. The study has also concluded that previous methods for analyzing PAHs using fluorescence spectroscopy used ...


Developing A Risk Assessment Protocol To Quantify Distribution And Uptake Of Persistent Organic Pollutants In Glacial Outflows, Kimberley Rain Miner 2018 University of Maine

Developing A Risk Assessment Protocol To Quantify Distribution And Uptake Of Persistent Organic Pollutants In Glacial Outflows, Kimberley Rain Miner

Electronic Theses and Dissertations

Pollutants released by industrialized nations between 1960 and 2004 have been transported northward through atmospheric processes and deposited into glaciated alpine ecosystems. Many of these chemicals retain their original structure and are absorbed into the biota thousands of miles away from where they were originally utilized. With a warming climate increasing the melt of alpine glaciers, these glaciers may be introducing growing amounts of toxins into the watershed. While studies have demonstrated the existence of resident pollutants within glaciated ecosystems, no one has developed a risk assessment to identify sources and quantity of risk posed by these compounds when released ...


Synthesis And Characterization Of Biodiesel Fuels From Furfuryl Alcohol And Spent Coffee Grounds, Amanda Raley 2018 Stephen F. Austin State University

Synthesis And Characterization Of Biodiesel Fuels From Furfuryl Alcohol And Spent Coffee Grounds, Amanda Raley

Electronic Theses and Dissertations

ABSTRACT

Biodiesel can be synthesized using several different triacylglycerides, alcohols, and catalysts. In this study, fatty acid methyl esters (FAMEs) and fatty acid ethyl esters (FAEEs) were produced from their respective alcohols and coffee oil, using either a basic (K2CO3) catalyst or an acidic catalyst (H2SO4). Fatty acid furfuryl esters (FAFurEs) were produced using commercially-purchased cooking oils (canola, olive, corn, sunflower, and peanut) with furfuryl alcohol, a basic (K2CO3) catalyst, a co-solvent (THF), and an ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate). All samples were produced using either conventional heating methods (CH) or microwave-assisted ...


Detrital Protein Contributes To Oyster Nutrition And Growth In The Damariscotta Estuary, Maine, Usa, Cheyenne M. Adams 2018 University of Maine School of Marine Science, Darling Marine Center

Detrital Protein Contributes To Oyster Nutrition And Growth In The Damariscotta Estuary, Maine, Usa, Cheyenne M. Adams

Electronic Theses and Dissertations

Oyster aquaculture is an expanding industry that relies on identifying and utilizing natural estuarine conditions for the economically viable production of a filter-feeding crop. The eastern oyster, Crassostrea virginica, is the principal species currently cultured in Maine. In addition to preferentially consumed phytoplankton, various detrital complexes (non-algal and/or non-living organic matter) may provide some nutrition to C. virginica between times of phytoplankton abundance. Here I investigated the importance of detrital proteins in supporting the growth of oysters cultured in the upper Damariscotta Estuary. Oyster aquaculture in this area is highly successful and previous reports indicate that labile detrital protein ...


Temporal Changes In Dissolved Calcium In Stream And River Waters In Western Kentucky Watershed, Adam Martin 2018 Murray State University

Temporal Changes In Dissolved Calcium In Stream And River Waters In Western Kentucky Watershed, Adam Martin

Scholars Week

Temporal Changes in Dissolved Calcium in Stream and River Waters in Western Kentucky Watershed


Using Spectral Methods To Obtain Particle Size Information From Optical Data: Applications To Measurements From Cares 2010, Dean B. Atkinson 2018 Portland State University

Using Spectral Methods To Obtain Particle Size Information From Optical Data: Applications To Measurements From Cares 2010, Dean B. Atkinson

Chemistry Faculty Publications and Presentations

Multi-wavelength in situ aerosol extinction, absorption and scattering measurements made at two ground sites during the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES) are analyzed using a spectral deconvolution method that allows extraction of particle-sizerelated information, including the fraction of extinction produced by the fine-mode particles and the effective radius of the fine mode. The spectral deconvolution method is typically applied to analysis of remote sensing measurements. Here, its application to in situ measurements allows for comparison with more direct measurement methods and validation of the retrieval approach. Overall, the retrieved finemode fraction and effective radius compare well with ...


Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher 2018 Old Dominion University

Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Though pyrogenic carbon (pyC) has been assumed to be predominantly stable, degradation and transfers of pyC between various pools have been found to influence its cycling and longevity in the environment. Dissolution via leaching may be the main control on loss processes such as microbial or abiotic oxidation, mineral sorption, or export to aquatic systems. Yet, little is known about the controls on pyrogenic dissolved organic matter (pyDOM) generation or composition. Here, the yield and composition of pyDOM generated through batch leaching of a thermal series of oak and grass biochars, as well as several non-pyrogenic reference materials, was compared ...


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